Saturday, February 28, 2009

Normal Takeoff - Takeoffs And Departure Climbs


A normal takeoff is one in which the airplane is headed
into the wind, or the wind is very light. Also, the takeoff surface is firm and of sufficient length to permit the
airplane to gradually accelerate to normal lift-off and
climb-out speed, and there are no obstructions along
the takeoff path.



There are two reasons for making a takeoff as nearly
into the wind as possible. First, the airplane's speed
while on the ground is much less than if the takeoff
were made downwind, thus reducing wear and stress
on the landing gear. Second, a shorter ground roll and
therefore much less runway length is required to
develop the minimum lift necessary for takeoff and
climb. Since the airplane depends on airspeed in order
to fly, a headwind provides some of that airspeed, even
with the airplane motionless, from the wind flowing
over the wings.

Friday, February 27, 2009

Prior To Takeoff - Takeoffs And Departure Climb


Before taxiing onto the runway or takeoff area, the
pilot should ensure that the engine is operating properly and that all controls, including flaps and trim tabs,
are set in accordance with the before takeoff checklist.
In addition, the pilot must make certain that the
approach and takeoff paths are clear of other aircraft.
At uncontrolled airports, pilots should announce their
intentions on the common traffic advisory frequency
(CTAF) assigned to that airport. When operating from
an airport with an operating control tower, pilots must
contact the tower operator and receive a takeoff clearance before taxiing onto the active runway.



It is not recommended to take off immediately behind
another aircraft, particularly large, heavily loaded
transport airplanes, because of the wake turbulence
that is generated.



While taxiing onto the runway, the pilot can select
ground reference points that are aligned with the
runway direction as aids to maintaining directional
control during the takeoff. These may be runway
centerline markings, runway lighting, distant trees,
towers, buildings, or mountain peaks.

Thursday, February 26, 2009

Terms And Definitions - Takeoffs And Departure Climbs


Although the takeoff and climb is one continuous
maneuver, it will be divided into three separate steps
for purposes of explanation: (1) the takeoff roll, (2) the
lift-off, and (3) the initial climb after becoming airborne. Takeoff and climb.



  • Takeoff Roll (ground roll)—the portion of the
    takeoff procedure during which the airplane is
    accelerated from a standstill to an airspeed that
    provides sufficient lift for it to become airborne.

  • Lift-off (rotation)—the act of becoming airborne as a result of the wings lifting the airplane
    off the ground or the pilot rotating the nose up,
    increasing the angle of attack to start a climb.

  • Initial Climb—begins when the airplane leaves
    the ground and a pitch attitude has been established to climb away from the takeoff area.
    Normally, it is considered complete when the
    plane has reached a safe maneuvering altitude,
    or an en route climb has been established.


Wednesday, February 25, 2009

S-Turns Across A Road


An S-turn across a road is a practice maneuver in
which the airplane's ground track describes semicircles
of equal radii on each side of a selected straight
line on the ground. S-Turns.
The straight line may
be a road, fence, railroad, or section line that lies perpendicular
to the wind, and should be of sufficient
length for making a series of turns. A constant altitude
should be maintained throughout the maneuver.



S-turns across a road present one of the most elementary
problems in the practical application of the turn
and in the correction for wind drift in turns. While the
application of this maneuver is considerably less
advanced in some respects than the rectangular course,
it is taught after the student has been introduced to that
maneuver in order that the student may have a knowledge
of the correction for wind drift in straight flight
along a reference line before the student attempt to
correct for drift by playing a turn.



The objectives of S-turns across a road are to develop
the ability to compensate for drift during turns, orient
the flightpath with ground references, follow an
assigned ground track, arrive at specified points on
assigned headings, and divide the pilot's attention. The



maneuver consists of crossing the road at a 90° angle
and immediately beginning a series of 180° turns of
uniform radius in opposite directions, re-crossing the
road at a 90° angle just as each 180° turn is completed.



To accomplish a constant radius ground track requires
a changing roll rate and angle of bank to establish the
wind correction angle. Both will increase or decrease
as groundspeed increases or decreases.



The bank must be steepest when beginning the turn on
the downwind side of the road and must be shallowed
gradually as the turn progresses from a downwind
heading to an upwind heading. On the upwind side, the
turn should be started with a relatively shallow bank
and then gradually steepened as the airplane turns from
an upwind heading to a downwind heading.



In this maneuver, the airplane should be rolled from
one bank directly into the opposite just as the reference
line on the ground is crossed.



Before starting the maneuver, a straight ground reference line or road that lies 90° to the direction of the
wind should be selected, then the area checked to
ensure that no obstructions or other aircraft are in the
immediate vicinity. The road should be approached
from the upwind side, at the selected altitude on a
downwind heading. When directly over the road, the
first turn should be started immediately. With the airplane headed downwind, the groundspeed is greatest
and the rate of departure from the road will be rapid;
so the roll into the steep bank must be fairly rapid to
attain the proper wind correction angle. This prevents
the airplane from flying too far from the road and
from establishing a ground track of excessive radius.



During the latter portion of the first 90° of turn when
the airplane's heading is changing from a downwind
heading to a crosswind heading, the groundspeed
becomes less and the rate of departure from the road
decreases. The wind correction angle will be at the
maximum when the airplane is headed directly crosswind.



After turning 90°, the airplane's heading becomes
more and more an upwind heading, the groundspeed
will decrease, and the rate of closure with the road
will become slower. If a constant steep bank were
maintained, the airplane would turn too quickly for
the slower rate of closure, and would be headed perpendicular to the road prematurely. Because of the
decreasing groundspeed and rate of closure while
approaching the upwind heading, it will be necessary
to gradually shallow the bank during the remaining
90° of the semicircle, so that the wind correction
angle is removed completely and the wings become
level as the 180° turn is completed at the moment the
road is reached.



At the instant the road is being crossed again, a turn in
the opposite direction should be started. Since the airplane is still flying into the headwind, the groundspeed
is relatively slow. Therefore, the turn will have to be
started with a shallow bank so as to avoid an excessive
rate of turn that would establish the maximum wind
correction angle too soon. The degree of bank should
be that which is necessary to attain the proper wind
correction angle so the ground track describes an arc
the same size as the one established on the downwind
side.



Since the airplane is turning from an upwind to a
downwind heading, the groundspeed will increase
and after turning 90°, the rate of closure with the road
will increase rapidly. Consequently, the angle of bank
and rate of turn must be progressively increased so
that the airplane will have turned 180° at the time it
reaches the road. Again, the rollout must be timed so
the airplane is in straight-and-level flight directly
over and perpendicular to the road.

Throu


ghout the maneuver a constant altitude should
be maintained, and the bank should be changing
constantly to effect a true semicircular ground track.



Often there is a tendency to increase the bank too
rapidly during the initial part of the turn on the
upwind side, which will prevent the completion of
the 180° turn before re-crossing the road. This is
apparent when the turn is not completed in time for
the airplane to cross the road at a perpendicular
angle. To avoid this error, the pilot must visualize the
desired half circle ground track, and increase the
bank during the early part of this turn. During the latter part of the turn, when approaching the road, the
pilot must judge the closure rate properly and
increase the bank accordingly, so as to cross the road
perpendicular to it just as the rollout is completed.



Common errors in the performance of S-turns across a
road are:



  • Failure to adequately clear the area.

  • Poor coordination.

  • Gaining or losing altitude.

  • Inability to visualize the half circle ground track.

  • Poor timing in beginning and recovering from
    turns.

  • Faulty correction for drift.

  • Inadequate visual lookout for other aircraft.


Takeoffs And Departure Climbs


This chapter discusses takeoffs and departure climbs in
tricycle landing gear (nosewheel-type) airplanes under
normal conditions, and under conditions which require
maximum performance. A thorough knowledge of
takeoff principles, both in theory and practice, will
often prove of extreme value throughout a pilot's
career. It will often prevent an attempted takeoff that
would result in an accident, or during an emergency,
make possible a takeoff under critical conditions when
a pilot with a less well rounded knowledge and technique would fail.



The takeoff, though relatively simple, often presents
the most hazards of any part of a flight. The importance
of thorough knowledge and faultless technique and
judgment cannot be overemphasized.



It must be remembered that the manufacturer's recommended procedures, including airplane configuration and
airspeeds, and other information relevant to takeoffs and
departure climbs in a specific make and model airplane are
contained in the FAA-approved Airplane Flight Manual
and/or Pilot'
airplane. If any of the information in this chapter dif

from the airplane manufacturer's recommendations as
contained in the AFM/POH, the airplane manufacturer's
recommendations take precedence.

Tuesday, February 24, 2009

Rectangular Course


Normally, the first ground reference maneuver the pilot
is introduced to is the rectangular course. Rectangular course.



The rectangular course is a training maneuver in which
the ground track of the airplane is equidistant from all
sides of a selected rectangular area on the ground. The
maneuver simulates the conditions encountered in an
airport traffic pattern. While performing the maneuver, the altitude and airspeed should be held constant.
The maneuver assists the student pilot in perfecting:



  • Practical application of the turn.

  • The division of attention between the flightpath,
    ground objects, and the handling of the airplane.

  • The timing of the start of a turn so that the turn
    will be fully established at a definite point over
    the ground.

  • The timing of the recovery from a turn so that a
    definite ground track will be maintained.

  • The establishing of a ground track and the determination of the appropriate "crab" angle.




Like those of other ground track maneuvers, one of the
objectives is to develop division of attention between
the flightpath and ground references, while controlling
the airplane and watching for other aircraft in the


vicinity. Another objective is to develop recognition of
drift toward or away from a line parallel to the intended
ground track. This will be helpful in recognizing drift
toward or from an airport runway during the various
legs of the airport traffic pattern.



For this maneuver, a square or rectangular field, or an
area bounded on four sides by section lines or roads
(the sides of which are approximately a mile in length),
should be selected well away from other air traffic. The
airplane should be flown parallel to and at a uniform
distance about one-fourth to one-half mile away from
the field boundaries, not above the boundaries. For
best results, the flightpath should be positioned outside
the field boundaries just far enough that they may be
easily observed from either pilot seat by looking out
the side of the airplane. If an attempt is made to fly
directly above the edges of the field, the pilot will have
no usable reference points to start and complete the
turns. The closer the track of the airplane is to the field
boundaries, the steeper the bank necessary at the turning points. Also, the pilot should be able to see the
edges of the selected field while seated in a normal
position and looking out the side of the airplane during
either a left-hand or right-hand course. The distance of
the ground track from the edges of the field should be
the same regardless of whether the course is flown to
the left or right. All turns should be started when the
airplane is abeam the corner of the field boundaries,
and the bank normally should not exceed 45°. These
should be the determining factors in establishing the
distance from the boundaries for performing the
maneuver.



Although the rectangular course may be entered from
any direction, this discussion assumes entry on a
downwind.



On the downwind leg, the wind is a tailwind and results
in an increased groundspeed. Consequently, the turn
onto the next leg is entered with a fairly fast rate of
roll-in with relatively steep bank. As the turn progresses, the bank angle is reduced gradually because
the tailwind component is diminishing, resulting in a
decreasing groundspeed.



During and after the turn onto this leg (the equivalent
of the base leg in a traffic pattern), the wind will tend
to drift the airplane away from the field boundary. To
compensate for the drift, the amount of turn will be
more than 90°.



The rollout from this turn must be such that as the
wings become level, the airplane is turned slightly
toward the field and into the wind to correct for drift.
The airplane should again be the same distance from
the field boundary and at the same altitude, as on other
legs. The base leg should be continued until the upwind

leg boundary is being approached. Once more the pilot
should anticipate drift and turning radius. Since drift
correction was held on the base leg, it is necessary to
turn less than 90° to align the airplane parallel to the
upwind leg boundary. This turn should be started with
a medium bank angle with a gradual reduction to a
shallow bank as the turn progresses. The rollout should
be timed to assure paralleling the boundary of the field
as the wings become level.



While the airplane is on the upwind leg, the next field
boundary should be observed as it is being approached,
to plan the turn onto the crosswind leg. Since the wind
is a headwind on this leg, it is reducing the airplane's
groundspeed and during the turn onto the crosswind
leg will try to drift the airplane toward the field. For
this reason, the roll-in to the turn must be slow and the
bank relatively shallow to counteract this effect. As the
turn progresses, the headwind component decreases,
allowing the groundspeed to increase. Consequently,
the bank angle and rate of turn are increased gradually
to assure that upon completion of the turn the crosswind ground track will continue the same distance
from the edge of the field. Completion of the turn with
the wings level should be accomplished at a point
aligned with the upwind corner of the field.



Simultaneously, as the wings are rolled level, the
proper drift correction is established with the airplane
turned into the wind. This requires that the turn be less
than a 90° change in heading. If the turn has been made
properly, the field boundary will again appear to be
one-fourth to one-half mile away. While on the crosswind leg, the wind correction angle should be adjusted
as necessary to maintain a uniform distance from the
field boundary.



As the next field boundary is being approached, the
pilot should plan the turn onto the downwind leg. Since
a wind correction angle is being held into the wind and
away from the field while on the crosswind leg, this
next turn will require a turn of more than 90°. Since
the crosswind will become a tailwind, causing the
groundspeed to increase during this turn, the bank initially should be medium and progressively increased
as the turn proceeds. To complete the turn, the rollout
must be timed so that the wings become level at a point
aligned with the crosswind corner of the field just as
the longitudinal axis of the airplane again becomes
parallel to the field boundary. The distance from the
field boundary should be the same as from the other
sides of the field.



Usually, drift should not be encountered on the upwind
or the downwind leg, but it may be difficult to find a
situation where the wind is blowing exactly parallel to
the field boundaries. This would make it necessary to
use a slight wind correction angle on all the legs. It is

important to anticipate the turns to correct for groundspeed,
drift, and turning radius. When the wind is
behind the airplane, the turn must be faster and steeper;
when it is ahead of the airplane, the turn must be
slower and shallower. These same techniques apply
while flying in airport traffic patterns.



Common errors in the performance of rectangular
courses are:


  • Failure to adequately clear the area.
  • Failure to establish proper altitude prior to
    entry. (Typically entering the maneuver while
    descending.)
  • Failure to establish appropriate wind correction
    angle resulting in drift.
  • Gaining or losing altitude.
  • Poor coordination. (Typically skidding in turns
    from a downwind heading and slipping in turns
    from an upwind heading.)
  • Abrupt control usage.
  • Inability to adequately divide attention between
    airplane control and maintaining ground track.
  • Improper timing in beginning and recovering
    from turns.
  • Inadequate visual lookout for other aircraft.


Weight And Balance Requirements


With each airplane that is approved for spinning, the
weight and balance requirements are important for
safe performance and recovery from the spin maneuver. Pilots must be aware that just minor weight or
balance changes can affect the airplane's spin
recovery characteristics. Such changes can either
alter or enhance the spin maneuver and/or recovery
characteristics. For example, the addition of weight
in the aft baggage compartment, or additional fuel,
may still permit the airplane to be operated within
CG, but could seriously affect the spin and recovery
characteristics.



An airplane that may be difficult to spin intentionally
in the Utility Category (restricted aft CG and reduced
weight) could have less resistance to spin entry in the
Normal Category (less restricted aft CG and increased
weight). This situation is due to the airplane being able
to generate a higher angle of attack and load factor.
Furthermore, an airplane that is approved for spins in
the Utility Category, but loaded in the Normal
Category, may not recover from a spin that is allowed
to progress beyond the incipient phase.



Common errors in the performance of intentional
spins are:



  • Failure to apply full rudder pressure in the desired
    spin direction during spin entry.

  • Failure to apply and maintain full up-elevator
    pressure during spin entry, resulting in a spiral.

  • Failure to achieve a fully stalled condition prior to
    spin entry.

  • Failure to apply full rudder against the spin during
    recovery.

  • Failure to apply sufficient forward-elevator
    pressure during recovery.

  • Failure to neutralize the rudder during recovery
    after rotation stops, resulting in a possible
    secondary spin.

  • Slow and overly cautious control movements
    during recovery.

  • Excessive back-elevator pressure after rotation
    stops, resulting in possible secondary stall.

  • Insufficient back-elevator pressure during
    recovery resulting in excessive airspeed.


Monday, February 23, 2009

Drift And Ground Track Control


Whenever any object is free from the ground, it is
affected by the medium with which it is surrounded.
This means that a free object will move in whatever
direction and speed that the medium moves.
















For example, if a powerboat is crossing a river and
the river is still, the boat could head directly to a point
on the opposite shore and travel on a straight course
to that point without drifting. However, if the river
were flowing swiftly, the water current would have to
be considered. That is, as the boat progresses forward
with its own power, it must also move upstream at the
same rate the river is moving it downstream. This is
accomplished by angling the boat upstream sufficiently to counteract the downstream flow. If this is
done, the boat will follow the desired track across
the river from the departure point directly to the
intended destination point. Should the boat not be
headed sufficiently upstream, it would drift with the
current and run aground at some point downstream
on the opposite bank. Wind drift.



As soon as an airplane becomes airborne, it is free of
ground friction. Its path is then affected by the air mass
in which it is flying; therefore, the airplane (like the
boat) will not always track along the ground in the
exact direction that it is headed. When flying with the
longitudinal axis of the airplane aligned with a road, it
may be noted that the airplane gets closer to or farther
from the road without any turn having been made. This

would indicate that the air mass is moving sideward in
relation to the airplane. Since the airplane is flying
within this moving body of air (wind), it moves or
drifts with the air in the same direction and speed, just
like the boat moved with the river current.



When flying straight and level and following a
selected ground track, the preferred method of correcting for wind drift is to head the airplane (wind
correction angle) sufficiently into the wind to cause
the airplane to move forward into the wind at the
same rate the wind is moving it sideways.
Depending on the wind velocity, this may require a
large wind correction angle or one of only a few
degrees. When the drift has been neutralized, the
airplane will follow the desired ground track.



To understand the need for drift correction during
flight, consider a flight with a wind velocity of 30
knots from the left and 90° to the direction the airplane
is headed. After 1 hour, the body of air in which the
airplane is flying will have moved 30 nautical miles
(NM) to the right. Since the airplane is moving with
this body of air, it too will have drifted 30 NM to the
right. In relation to the air, the airplane moved forward, but in relation to the ground, it moved forward
as well as 30 NM to the right.



There are times when the pilot needs to correct for drift
while in a turn. Effect of wind during a turn.
Throughout the turn the
wind will be acting on the airplane from constantly
changing angles. The relative wind angle and speed


govern the time it takes for the airplane to progress
through any part of a turn. This is due to the constantly
changing groundspeed. When the airplane is headed
into the wind, the groundspeed is decreased; when
headed downwind, the groundspeed is increased.
Through the crosswind portion of a turn, the airplane
must be turned sufficiently into the wind to counteract
drift.



To follow a desired circular ground track, the wind correction angle must be varied in a timely manner
because of the varying groundspeed as the turn progresses. The faster the groundspeed, the faster the wind
correction angle must be established; the slower the
groundspeed, the slower the wind correction angle may
be established. It can be seen then that the steepest
bank and fastest rate of turn should be made on the
downwind portion of the turn and the shallowest bank
and slowest rate of turn on the upwind portion.



The principles and techniques of varying the angle of
bank to change the rate of turn and wind correction
angle for controlling wind drift during a turn are the
same for all ground track maneuvers involving
changes in direction of flight.



When there is no wind, it should be simple to fly along
a ground track with an arc of exactly 180° and a constant radius because the flightpath and ground track
would be identical. This can be demonstrated by
approaching a road at a 90° angle and, when directly
over the road, rolling into a medium-banked turn, then
maintaining the same angle of bank throughout the
180° of turn. Effect of wind during turns.



To complete the turn, the rollout should be started at a
point where the wings will become level as the airplane
again reaches the road at a 90° angle and will be
directly over the road just as the turn is completed. This
would be possible only if there were absolutely no
wind and if the angle of bank and the rate of turn
remained constant throughout the entire maneuver.



If the turn were made with a constant angle of bank
and a wind blowing directly across the road, it would
result in a constant radius turn through the air.
However, the wind effects would cause the ground
track to be distorted from a constant radius turn or
semicircular path. The greater the wind velocity, the
greater would be the difference between the desired
ground track and the flightpath. To counteract this
drift, the flightpath can be controlled by the pilot in
such a manner as to neutralize the effect of the wind,
and cause the ground track to be a constant radius
semicircle.



The effects of wind during turns can be demonstrated
after selecting a road, railroad, or other ground reference that forms a straight line parallel to the wind. Fly
into the wind directly over and along the line and then
make a turn with a constant medium angle of bank for
360° of turn.
The airplane will return to a
point directly over the line but slightly downwind from
the starting point, the amount depending on the wind
velocity and the time required to complete the turn.
The path over the ground will be an elongated circle,
although in reference to the air it is a perfect circle.
Straight flight during the upwind segment after completion of the turn is necessary to bring the airplane
back to the starting position.




A similar 360° turn may be started at a specific point
over the reference line, with the airplane headed
directly downwind. In this demonstration, the effect of
wind during the constant banked turn will drift the airplane to a point where the line is reintercepted, but the
360° turn will be completed at a point downwind from
the starting point.



Another reference line which lies directly crosswind
may be selected and the same procedure repeated,
showing that if wind drift is not corrected the airplane
will, at the completion of the 360° turn, be headed in
the original direction but will have drifted away from
the line a distance dependent on the amount of wind.



From these demonstrations, it can be seen where and
why it is necessary to increase or decrease the angle of
bank and the rate of turn to achieve a desired track over
the ground. The principles and techniques involved can
be practiced and evaluated by the performance of the
ground track maneuvers discussed in this chapter.

Intentional Spins


The intentional spinning of an airplane, for which the
spin maneuver is not specifically approved, is NOT
authorized by this handbook or by the Code of Federal
Regulations. The official sources for determining if the
spin maneuver IS APPROVED or NOT APPROVED
for a specific airplane are:



  • Type Certificate Data Sheets or the Aircraft
    Specifications.

  • The limitation section of the FAA-approved
    AFM/POH. The limitation sections may provide
    additional specific requirements for spin
    authorization, such as limiting gross weight, CG
    range, and amount of fuel.

  • On a placard located in clear view of the pilot in
    the airplane, NO ACROBATIC MANEUVERS
    INCLUDING SPINS APPROVED. In airplanes
    placarded against spins, there is no assurance that
    recovery from a fully developed spin is possible.




There are occurrences involving airplanes wherein
spin restrictions are intentionally ignored by some
pilots. Despite the installation of placards prohibiting
intentional spins in these airplanes, a number of pilots,
and some flight instructors, attempt to justify the
maneuver, rationalizing that the spin restriction results
merely because of a "technicality" in the airworthiness
standards.



Some pilots reason that the airplane was spin tested
during its certification process and, therefore, no
problem should result from demonstrating or
practicing spins. However, those pilots overlook the
fact that a normal category airplane certification only
requires the airplane recover from a one-turn spin in
not more than one additional turn or 3 seconds,




whichever takes longer. This same test of controllability can also be used in certificating an airplane in the
Utility category (14 CFR section 23.221 (b)).



The point is that 360° of rotation (one-turn spin) does
not provide a stabilized spin. If the airplane's
controllability has not been explored by the
engineering test pilot beyond the certification
requirements, prolonged spins (inadvertent or
intentional) in that airplane place an operating pilot in
an unexplored flight situation. Recovery may be
difficult or impossible.



In 14 CFR part 23, "Airworthiness Standards: Normal,
Utility, Acrobatic, and Commuter Category
Airplanes," there are no requirements for investigation
of controllability in a true spinning condition for the
Normal category airplanes. The one-turn "margin of
safety" is essentially a check of the airplane's controllability in a delayed recovery from a stall. Therefore,
in airplanes placarded against spins there is absolutely
no assurance whatever that recovery from a fully
developed spin is possible under any circumstances
.
The pilot of an airplane placarded against intentional
spins should assume that the airplane may well become
uncontrollable in a spin.

Sunday, February 22, 2009

Maneuvering By Reference To Ground Objects


Ground track or ground reference maneuvers are performed at a relatively low altitude while applying wind
drift correction as needed to follow a predetermined
track or path over the ground. They are designed to
develop the ability to control the airplane, and to recognize and correct for the effect of wind while dividing
attention among other matters. This requires planning
ahead of the airplane, maintaining orientation in relation
to ground objects, flying appropriate headings to follow
a desired ground track, and being cognizant of other air
traffic in the immediate vicinity.



Ground reference maneuvers should be flown at an altitude of approximately 600 to 1,000 feet AGL. The
actual altitude will depend on the speed and type of airplane to a large extent, and the following factors should
be considered.



  • The speed with relation to the ground should not
    be so apparent that events happen too rapidly.

  • The radius of the turn and the path of the airplane
    over the ground should be easily noted and
    changes planned and effected as circumstances
    require.

  • Drift should be easily discernable, but not tax the
    student too much in making corrections.

  • Objects on the ground should appear in their proportion and size.

  • The altitude should be low enough to render any
    gain or loss apparent to the student, but in no case
    lower than 500 feet above the highest obstruction.




During these maneuvers, both the instructor and the
student should be alert for available forced-landing
fields. The area chosen should be away from communities, livestock, or groups of people to prevent possible
annoyance or hazards to others. Due to the altitudes at
which these maneuvers are performed, there is little
time available to search for a suitable field for landing
in the event the need arises.

Recovery Phase


The recovery phase occurs when the angle of attack of
the wings decreases below the critical angle of attack
and autorotation slows. Then the nose steepens and
rotation stops. This phase may last for a quarter turn to
several turns.



To recover, control inputs are initiated to disrupt the
spin equilibrium by stopping the rotation and stall. To
accomplish spin recovery, the manufacturer's

recommended procedures should be followed. In the
absence of the manufacturer's recommended spin
recovery procedures and techniques, the following
spin recovery procedures are recommended.




      Step 1—REDUCE THE POWER (THROTTLE)
      TO IDLE
      . Power aggravates the spin
      characteristics. It usually results in a flatter spin
      attitude and increased rotation rates.



      Step 2—POSITION THE AILERONS TO
      NEUTRAL
      . Ailerons may have an adverse effect
      on spin recovery. Aileron control in the direction
      of the spin may speed up the rate of rotation and
      delay the recovery. Aileron control opposite the
      direction of the spin may cause the down aileron
      to move the wing deeper into the stall and
      aggravate the situation. The best procedure is to
      ensure that the ailerons are neutral.



      Step 3—APPLY FULL OPPOSITE RUDDER
      AGAINST THE ROTATION
      . Make sure that full
      (against the stop) opposite rudder has been
      applied.



      Step 4—APPLY A POSITIVE AND BRISK,
      STRAIGHT FORWARD MOVEMENT OF THE
      ELEVATOR CONTROL FORWARD OF THE
      NEUTRAL TO BREAK THE STALL
      . This
      should be done immediately after full rudder
      application. The forceful movement of the
      elevator will decrease the excessive angle of attack
      and break the stall. The controls should be held
      firmly in this position. When the stall is "broken,"
      the spinning will stop.



      Step 5—AFTER SPIN ROTATION STOPS,
      NEUTRALIZE THE RUDDER
      . If the rudder is
      not neutralized at this time, the ensuing increased
      airspeed acting upon a deflected rudder will cause
      a yawing or skidding effect.



      Slow and overly cautious control movements
      during spin recovery must be avoided. In certain
      cases it has been found that such movements result
      in the airplane continuing to spin indefinitely, even
      with anti-spin inputs. A brisk and positive
      technique, on the other hand, results in a more
      positive spin recovery.



      Step 6—BEGIN APPLYING BACK-ELEVATOR
      PRESSURE TO RAISE THE NOSE TO LEVEL
      FLIGHT
      . Caution must be used not to apply
      excessive back-elevator pressure after the rotation
      stops. Excessive back-elevator pressure can cause
      a secondary stall and result in another spin. Care
      should be taken not to exceed the "G" load limits
      and airspeed limitations during recovery. If the

      flaps and/or retractable landing gear are extended
      prior to the spin, they should be retracted as soon
      as possible after spin entry.



It is important to remember that the above spin
recovery procedures and techniques are recommended
for use only in the absence of the manufacturer's
procedures. Before any pilot attempts to begin spin
training, that pilot must be familiar with the procedures
provided by the manufacturer for spin recovery.



The most common problems in spin recovery include
pilot confusion as to the direction of spin rotation and
whether the maneuver is a spin versus spiral. If the
airspeed is increasing, the airplane is no longer in a
spin but in a spiral. In a spin, the airplane is stalled.
The indicated airspeed, therefore, should reflect
stall speed.

Saturday, February 21, 2009

Purpose And Scope - Ground Reference Maneuvers


Ground reference maneuvers and their related factors
are used in developing a high degree of pilot skill.
Although most of these maneuvers are not performed
as such in normal everyday flying, the elements and
principles involved in each are applicable to performance of the customary pilot operations. They aid the
pilot in analyzing the effect of wind and other forces
acting on the airplane and in developing a fine control touch, coordination, and the division of attention
necessary for accurate and safe maneuvering of the
airplane.



All of the early part of the pilot's training has been conducted at relatively high altitudes, and for the purpose
of developing technique, knowledge of maneuvers,
coordination, feel, and the handling of the airplane in
general. This training will have required that most of
the pilot's attention be given to the actual handling of
the airplane, and the results of control pressures on the
action and attitude of the airplane.



If permitted to continue beyond the appropriate training
stage, however, the student pilot's concentration of
attention will become a fixed habit, one that will seriously detract from the student's ease and safety as a
pilot, and will be very difficult to eliminate. Therefore,
it is necessary, as soon as the pilot shows proficiency in
the fundamental maneuvers, that the pilot be introduced
to maneuvers requiring outside attention on a practical
application of these maneuvers and the knowledge
gained.



It should be stressed that, during ground reference
maneuvers, it is equally important that basic flying
technique previously learned be maintained. The
flight instructor should not allow any relaxation of the
student's previous standard of technique simply
because a new factor is added. This requirement
should be maintained throughout the student's
progress from maneuver to maneuver. Each new
maneuver should embody some advance and include
the principles of the preceding one in order that continuity be maintained. Each new factor introduced
should be merely a step-up of one already learned so
that orderly, consistent progress can be made.

Incipient Phase


The incipient phase is from the time the airplane stalls
and rotation starts until the spin has fully developed.
This change may take up to two turns for most airplanes.
Incipient spins that are not allowed to develop into a
steady-state spin are the most commonly used in the
introduction to spin training and recovery techniques. In


this phase, the aerodynamic and inertial forces have not
achieved a balance. As the incipient spin develops, the
indicated airspeed should be near or below stall airspeed,
and the turn-and-slip indicator should indicate
the direction of the spin.



The incipient spin recovery procedure should be
commenced prior to the completion of 360° of
rotation. The pilot should apply full rudder opposite
the direction of rotation. If the pilot is not sure of the
direction of the spin, check the turn-and-slip indicator;
it will show a deflection in the direction of rotation.

Friday, February 20, 2009

Noise Abatement


Aircraft noise problems have become a major concern at
many airports throughout the country. Many local communities have pressured airports into developing specific
operational procedures that will help limit aircraft noise
while operating over nearby areas. For years now, the
FAA, airport managers, aircraft operators, pilots, and special interest groups have been working together to minimize aircraft noise for nearby sensitive areas. As a result,
noise abatement procedures have been developed for
many of these airports that include standardized profiles
and procedures to achieve these lower noise goals.



Airports that have noise abatement procedures provide
information to pilots, operators, air carriers, air traffic
facilities, and other special groups that are applicable
to their airport. These procedures are available to the
aviation community by various means. Most of this
information comes from the Airport/Facility Directory,
local and regional publications, printed handouts, operator bulletin boards, safety briefings, and local air traffic facilities.



At airports that use noise abatement procedures,
reminder signs may be installed at the taxiway hold
positions for applicable runways. These are to remind
pilots to use and comply with noise abatement procedures on departure. Pilots who are not familiar with
these procedures should ask the tower or air traffic
facility for the recommended procedures. In any case,
pilots should be considerate of the surrounding community while operating their airplane to and from such
an airport. This includes operating as quietly, yet safely
as possible.

Developed Phase


The developed phase occurs when the airplane's
angular rotation rate, airspeed, and vertical speed are
stabilized while in a flightpath that is nearly vertical.
This is where airplane aerodynamic forces and inertial
forces are in balance, and the attitude, angles, and selfsustaining
motions about the vertical axis are constant
or repetitive. The spin is in equilibrium.

Thursday, February 19, 2009

Rejected Takeoff - Engine Failure


Emergency or abnormal situations can occur during a
takeoff that will require a pilot to reject the takeoff
while still on the runway. Circumstances such as a
malfunctioning powerplant, inadequate acceleration,
runway incursion, or air traffic conflict may be reasons for a rejected takeoff.



Prior to takeoff, the pilot should have in mind a
point along the runway at which the airplane
should be airborne. If that point is reached and the
airplane is not airborne, immediate action should
be taken to discontinue the takeoff. Properly
planned and executed, chances are excellent the
airplane can be stopped on the remaining runway
without using extraordinary measures, such as
excessive braking that may result in loss of directional control, airplane damage, and/or personal
injury.



In the event a takeoff is rejected, the power should be
reduced to idle and maximum braking applied while
maintaining directional control. If it is necessary to
shut down the engine due to a fire, the mixture control
should be brought to the idle cutoff position and the
magnetos turned off. In all cases, the manufacturer's
emergency procedure should be followed.



What characterizes all power loss or engine failure
occurrences after lift-off is urgency. In most instances,
the pilot has only a few seconds after an engine failure
to decide what course of action to take and to execute
it. Unless prepared in advance to make the proper decision, there is an excellent chance the pilot will make a
poor decision, or make no decision at all and allow
events to rule.



In the event of an engine failure on initial climb-out,
the pilot's first responsibility is to maintain aircraft
control. At a climb pitch attitude without power, the
airplane will be at or near a stalling angle of attack.
At the same time, the pilot may still be holding right
rudder. It is essential the pilot immediately lower the
pitch attitude to prevent a stall and possible spin.
The pilot should establish a controlled glide toward
a plausible landing area (preferably straight ahead
on the remaining runway).

Entry Phase


The entry phase is where the pilot provides the
necessary elements for the spin, either accidentally or
intentionally. The entry procedure for demonstrating a
spin is similar to a power-off stall. During the entry,
the power should be reduced slowly to idle, while
simultaneously raising the nose to a pitch attitude that
will ensure a stall. As the airplane approaches a stall,
smoothly apply full rudder in the direction of the
desired spin rotation while applying full back (up)
elevator to the limit of travel. Always maintain the
ailerons in the neutral position during the spin
procedure unless AFM/POH specifies otherwise.

Wednesday, February 18, 2009

Initial Climb - Soft-Rough-Field Takeoff And Climb


After a positive rate of climb is established, and the airplane has accelerated to VY, retract the landing gear and
flaps, if equipped. If departing from an airstrip with wet
snow or slush on the takeoff surface, the gear should not
be retracted immediately. This allows for any wet snow
or slush to be air-dried. In the event an obstacle must be
cleared after a soft-field takeoff, the climb-out is performed at VX until the obstacle has been cleared. After
reaching this point, the pitch attitude is adjusted to VY
and the gear and flaps are retracted. The power may
then be reduced to the normal climb setting.






Common errors in the performance of soft/rough field
takeoff and climbs are:



  • Failure to adequately clear the area.

  • Insufficient back-elevator pressure during initial
    takeoff roll resulting in inadequate angle of
    attack.

  • Failure to cross-check engine instruments for
    indications of proper operation after applying
    power.

  • Poor directional control.

  • Climbing too steeply after lift-off.

  • Abrupt and/or excessive elevator control while
    attempting to level off and accelerate after liftoff.

  • Allowing the airplane to "mush" or settle resulting in an inadvertent touchdown after lift-off.

  • Attempting to climb out of ground effect area
    before attaining sufficient climb speed.

  • Failure to anticipate an increase in pitch attitude
    as the airplane climbs out of ground effect.


Spin Procedures


The flight instructor should demonstrate spins in those
airplanes that are approved for spins. Special spin
procedures or techniques required for a particular
airplane are not presented here. Before beginning any
spin operations, the following items should be
reviewed.



  • The airplane's AFM/POH limitations section,
    placards, or type certification data, to determine if
    the airplane is approved for spins.

  • Weight and balance limitations.

  • Recommended entry and recovery procedures.

  • The requirements for parachutes. It would be
    appropriate to review a current Title 14 of the
    Code of Federal Regulations (14 CFR) part 91 for
    the latest parachute requirements.





A thorough airplane preflight should be accomplished
with special emphasis on excess or loose items that
may affect the weight, center of gravity, and controllability of the airplane. Slack or loose control cables
(particularly rudder and elevator) could prevent full
anti-spin control deflections and delay or preclude
recovery in some airplanes.



Prior to beginning spin training, the flight area, above
and below the airplane, must be clear of other air
traffic. This may be accomplished while slowing the
airplane for the spin entry. All spin training should be
initiated at an altitude high enough for a completed
recovery at or above 1,500 feet AGL.



It may be appropriate to introduce spin training by first
practicing both power-on and power-off stalls, in a
clean configuration. This practice would be used to
familiarize the student with the airplane's specific stall
and recovery characteristics. Care should be taken with
the handling of the power (throttle) in entries and
during spins. Carburetor heat should be applied
according to the manufacturer's recommendations.



There are four phases of a spin: entry, incipient,
developed, and recovery. Spin entry and recovery.

Tuesday, February 17, 2009

Lift-Off - Soft-Rough-Field Takeoff And Climb


After becoming airborne, the nose should be lowered
very gently with the wheels clear of the surface to
allow the airplane to accelerate to VY, or VX if obstacles must be cleared. Extreme care must be exercised
immediately after the airplane becomes airborne and
while it accelerates, to avoid settling back onto the surface. An attempt to climb prematurely or too steeply
may cause the airplane to settle back to the surface as
a result of losing the benefit of ground effect. An
attempt to climb out of ground effect before sufficient
climb airspeed is attained may result in the airplane
being unable to climb further as the ground effect area
is transited, even with full power. Therefore, it is
essential that the airplane remain in ground effect until
at least VX is reached. This requires feel for the airplane, and a very fine control touch, in order to avoid
over-controlling the elevator as required control pressures change with airplane acceleration.

Spins


A spin may be defined as an aggravated stall that
results in what is termed "autorotation" wherein the
airplane follows a downward corkscrew path. As the
airplane rotates around a vertical axis, the rising wing
is less stalled than the descending wing creating a
rolling, yawing, and pitching motion. The airplane is
basically being forced downward by gravity, rolling,
yawing, and pitching in a spiral path. Spin-an aggravated stall and autorotation.


The autorotation results from an unequal angle of
attack on the airplane's wings. The rising wing has a
decreasing angle of attack, where the relative lift
increases and the drag decreases. In effect, this wing is
less stalled. Meanwhile, the descending wing has an

increasing angle of attack, past the wing's critical angle
of attack (stall) where the relative lift decreases and
drag increases.



A spin is caused when the airplane's wing exceeds its
critical angle of attack (stall) with a sideslip or yaw
acting on the airplane at, or beyond, the actual stall.
During this uncoordinated maneuver, a pilot may not
be aware that a critical angle of attack has been
exceeded until the airplane yaws out of control toward
the lowering wing. If stall recovery is not initiated
immediately, the airplane may enter a spin.



If this stall occurs while the airplane is in a slipping or
skidding turn, this can result in a spin entry and
rotation in the direction that the rudder is being
applied, regardless of which wingtip is raised.



Many airplanes have to be forced to spin and require
considerable judgment and technique to get the spin
started. These same airplanes that have to be forced to
spin, may be accidentally put into a spin by
mishandling the controls in turns, stalls, and flight at
minimum controllable airspeeds. This fact is additional
evidence of the necessity for the practice of stalls until
the ability to recognize and recover from them
is developed.



Often a wing will drop at the beginning of a stall.
When this happens, the nose will attempt to move
(yaw) in the direction of the low wing. This is where
use of the rudder is important during a stall. The
correct amount of opposite rudder must be applied to
keep the nose from yawing toward the low wing. By
maintaining directional control and not allowing the
nose to yaw toward the low wing, before stall recovery
is initiated, a spin will be averted. If the nose is allowed
to yaw during the stall, the airplane will begin to slip in
the direction of the lowered wing, and will enter a spin.
An airplane must be stalled in order to enter a spin;
therefore, continued practice in stalls will help the pilot
develop a more instinctive and prompt reaction in
recognizing an approaching spin. It is essential to learn
to apply immediate corrective action any time it is
apparent that the airplane is nearing spin conditions. If
it is impossible to avoid a spin, the pilot should
immediately execute spin recovery procedures.

Monday, February 16, 2009

Takeoff Roll - Soft-Rough-Field Takeoff And Climb


As the airplane is aligned with the takeoff path, takeoff
power is applied smoothly and as rapidly as the power-
plant will accept it without faltering. As the airplane


accelerates, enough back-elevator pressure should be
applied to establish a positive angle of attack and to
reduce the weight supported by the nosewheel.



When the airplane is held at a nose-high attitude
throughout the takeoff run, the wings will, as speed
increases and lift develops, progressively relieve the
wheels of more and more of the airplane's weight,
thereby minimizing the drag caused by surface irregularities or adhesion. If this attitude is accurately maintained,
the airplane will virtually fly itself off the ground,
becoming airborne at airspeed slower than a safe climb
speed because of ground effect. Soft field takeoff.

Elevator Trim Stall


The elevator trim stall maneuver shows what can happen when full power is applied for a go-around and
positive control of the airplane is not maintained.
Elevator trim stall.
Such a situation may occur during a
go-around procedure from a normal landing approach

or a simulated forced landing approach, or
immediately after a takeoff. The objective of the
demonstration is to show the importance of making
smooth power applications, overcoming strong trim
forces and maintaining positive control of the airplane
to hold safe flight attitudes, and using proper and
timely trim techniques.



At a safe altitude and after ensuring that the area is
clear of other air traffic, the pilot should slowly retard
the throttle and extend the landing gear (if retractable
gear). One-half to full flaps should be lowered, the
throttle closed, and altitude maintained until the
airspeed approaches the normal glide speed. When the
normal glide is established, the airplane should be
trimmed for the glide just as would be done during a
landing approach (nose-up trim).



During this simulated final approach glide, the throttle
is then advanced smoothly to maximum allowable
power as would be done in a go-around procedure. The
combined forces of thrust, torque, and back-elevator
trim will tend to make the nose rise sharply and turn to
the left.



When the throttle is fully advanced and the pitch
attitude increases above the normal climbing attitude
and it is apparent that a stall is approaching, adequate
forward pressure must be applied to return the airplane
to the normal climbing attitude. While holding the
airplane in this attitude, the trim should then be
adjusted to relieve the heavy control pressures and the
normal go-around and level-off procedures completed.



The pilot should recognize when a stall is approaching,
and take prompt action to prevent a completely stalled
condition. It is imperative that a stall not occur during
an actual go-around from a landing approach.



Common errors in the performance of intentional stalls
are:



  • Failure to adequately clear the area.

  • Inability to recognize an approaching stall
    condition through feel for the airplane.

  • Premature recovery.

  • Over-reliance on the airspeed indicator while
    excluding other cues.

  • Inadequate scanning resulting in an unintentional
    wing-low condition during entry.

  • Excessive back-elevator pressure resulting in an
    exaggerated nose-up attitude during entry.

  • Inadequate rudder control.

  • Inadvertent secondary stall during recovery.

  • Failure to maintain a constant bank angle during
    turning stalls.

  • Excessive forward-elevator pressure during
    recovery resulting in negative load on the wings.

  • Excessive airspeed buildup during recovery.

  • Failure to take timely action to prevent a full stall
    during the conduct of imminent stalls.


Sunday, February 15, 2009

Soft-Rough-Field Takeoff And Climb


Takeoffs and climbs from soft fields require the use of
operational techniques for getting the airplane airborne
as quickly as possible to eliminate the drag caused by
tall grass, soft sand, mud, and snow, and may or may
not require climbing over an obstacle. The technique
makes judicious use of ground effect and requires a
feel for the airplane and fine control touch. These same
techniques are also useful on a rough field where it is
advisable to get the airplane off the ground as soon as
possible to avoid damaging the landing gear.



Soft surfaces or long, wet grass usually reduces the airplane's acceleration during the takeoff roll so much
that adequate takeoff speed might not be attained if
normal takeoff techniques were employed.



It should be emphasized that the correct takeoff
procedure for soft fields is quite different from
that appropriate for short fields with firm, smooth
surfaces. To minimize the hazards associated with
takeoffs from soft or rough fields, support of the
airplane's weight must be transferred as rapidly
as possible from the wheels to the wings as the
takeoff roll proceeds. Establishing and maintaining a relatively high angle of attack or nose-high
pitch attitude as early as possible does this. Wing
flaps may be lowered prior to starting the takeoff
(if recommended by the manufacturer) to provide
additional lift and to transfer the airplane's weight
from the wheels to the wings as early as possible.



Stopping on a soft surface, such as mud or snow, might
bog the airplane down; therefore, it should be kept in
continuous motion with sufficient power while lining
up for the takeoff roll.

Cross-Control Stall


The objective of a cross-control stall demonstration
maneuver is to show the effect of improper control
technique and to emphasize the importance of using
coordinated control pressures whenever making turns.
This type of stall occurs with the controls crossed—
aileron pressure applied in one direction and rudder
pressure in the opposite direction.



In addition, when excessive back-elevator pressure is
applied, a cross-control stall may result. This is a stall
that is most apt to occur during a poorly planned and
executed base-to-final approach turn, and often is the
result of overshooting the centerline of the runway
during that turn. Normally, the proper action to correct
for overshooting the runway is to increase the rate of
turn by using coordinated aileron and rudder. At the
relatively low altitude of a base-to-final approach turn,
improperly trained pilots may be apprehensive of
steepening the bank to increase the rate of turn, and
rather than steepening the bank, they hold the bank
constant and attempt to increase the rate of turn by
adding more rudder pressure in an effort to align it
with the runway.





The addition of inside rudder pressure will cause the
speed of the outer wing to increase, therefore, creating
greater lift on that wing. To keep that wing from rising
and to maintain a constant angle of bank, opposite
aileron pressure needs to be applied. The added inside
rudder pressure will also cause the nose to lower in
relation to the horizon. Consequently, additional
back-elevator pressure would be required to maintain a
constant-pitch attitude. The resulting condition is a
turn with rudder applied in one direction, aileron in the
opposite direction, and excessive back-elevator
pressure—a pronounced cross-control condition.



Since the airplane is in a skidding turn during the
cross-control condition, the wing on the outside of the
turn speeds up and produces more lift than the inside
wing; thus, the airplane starts to increase its bank. The
down aileron on the inside of the turn helps drag that
wing back, slowing it up and decreasing its lift, which
requires more aileron application. This further causes
the airplane to roll. The roll may be so fast that it is
possible the bank will be vertical or past vertical before
it can be stopped.

For the d


emonstration of the maneuver, it is important
that it be entered at a safe altitude because of the
possible extreme nosedown attitude and loss of
altitude that may result.



Before demonstrating this stall, the pilot should clear
the area for other air traffic while slowly retarding the
throttle. Then the landing gear (if retractable gear)
should be lowered, the throttle closed, and the altitude
maintained until the airspeed approaches the normal
glide speed. Because of the possibility of exceeding
the airplane's limitations, flaps should not be extended.
While the gliding attitude and airspeed are being
established, the airplane should be retrimmed. When
the glide is stabilized, the airplane should be rolled into
a medium-banked turn to simulate a final approach
turn that would overshoot the centerline of the runway.



During the turn, excessive rudder pressure should be
applied in the direction of the turn but the bank held
constant by applying opposite aileron pressure. At the
same time, increased back-elevator pressure is
required to keep the nose from lowering.



All of these control pressures should be increased until
the airplane stalls. When the stall occurs, recovery is
made by releasing the control pressures and increasing
power as necessary to recover.



In a cross-control stall, the airplane often stalls with
little warning. The nose may pitch down, the inside
wing may suddenly drop, and the airplane may
continue to roll to an inverted position. This is usually
the beginning of a spin. It is obvious that close to the
ground is no place to allow this to happen.



Recovery must be made before the airplane enters an
abnormal attitude (vertical spiral or spin); it is a simple
matter to return to straight-and-level flight by
coordinated use of the controls. The pilot must be able
to recognize when this stall is imminent and must take
immediate action to prevent a completely stalled
condition. It is imperative that this type of stall not
occur during an actual approach to a landing, since
recovery may be impossible prior to ground contact
due to the low altitude.



The flight instructor should be aware that during traffic
pattern operations, any conditions that result in
overshooting the turn from base leg to final approach,
dramatically increases the possibility of an
unintentional accelerated stall while the airplane is in a
cross-control condition.

Saturday, February 14, 2009

Initial Climb - Ground Effect On Takeoff


On short-field takeoffs, the landing gear and flaps
should remain in takeoff position until clear of obstacles (or as recommended by the manufacturer) and VY
has been established. It is generally unwise for the pilot
to be looking in the cockpit or reaching for landing
gear and flap controls until obstacle clearance is
assured. When the airplane is stabilized at VY, the gear
(if equipped) and then the flaps should be retracted. It
is usually advisable to raise the flaps in increments to
avoid sudden loss of lift and settling of the airplane.
Next, reduce the power to the normal climb setting or
as recommended by the airplane manufacturer.



Common errors in the performance of short-field takeoffs and maximum performance climbs are:





  • Failure to adequately clear the area.

  • Failure to utilize all available runway/takeoff
    area.

  • Failure to have the airplane properly trimmed
    prior to takeoff.

  • Premature lift-off resulting in high drag.

  • Holding the airplane on the ground unnecessarily
    with excessive forward-elevator pressure.

  • Inadequate rotation resulting in excessive speed
    after lift-off.

  • Inability to attain/maintain best angle-of-climb
    airspeed.




  • Fixation on the airspeed indicator during initial
    climb.

  • Premature retraction of landing gear and/or wing
    flaps.


Lift-Off - Ground Effect On Takeoff


Approaching best angle-of-climb speed (VX), the airplane
should be smoothly and firmly lifted off, or rotated, by
applying back-elevator pressure to an attitude that will
result in the best angle-of-climb airspeed (VX). Since the
airplane will accelerate more rapidly after lift-off, additional back-elevator pressure becomes necessary to hold a
constant airspeed. After becoming airborne, a wings level
climb should be maintained at VX until obstacles have
been cleared or, if no obstacles are involved, until an altitude of at least 50 feet above the takeoff surface is attained.
Thereafter, the pitch attitude may be lowered slightly, and
the climb continued at best rate-of-climb speed (VY) until
reaching a safe maneuvering altitude. Remember that an
attempt to pull the airplane off the ground prematurely, or
to climb too steeply, may cause the airplane to settle back
to the runway or into the obstacles. Even if the airplane
remains airborne, the initial climb will remain flat and
climb performance/obstacle clearance ability seriously
degraded until best angle-of-climb airspeed (VX) is
achieved. Effect of premature lift-off



The objective is to rotate to the appropriate pitch attitude at (or near) best angle-of-climb airspeed. It should
be remembered, however, that some airplanes will
have a natural tendency to lift off well before reaching
VX. In these airplanes, it may be necessary to allow the
airplane to lift off in ground effect and then reduce
pitch attitude to level until the airplane accelerates to
best angle-of-climb airspeed with the wheels just clear
of the runway surface. This method is preferable to
forcing the airplane to remain on the ground with forward-elevator pressure until best angle-of-climb speed
is attained. Holding the airplane on the ground unnecessarily puts excessive pressure on the nosewheel, may
result in "wheelbarrowing," and will hinder both
acceleration and overall airplane performance.

Accelerated Stalls


Though the stalls just discussed normally occur at a
specific airspeed, the pilot must thoroughly understand

that all stalls result solely from attempts to fly at
excessively high angles of attack. During flight, the
angle of attack of an airplane wing is determined by a
number of factors, the most important of which are the
airspeed, the gross weight of the airplane, and the load
factors imposed by maneuvering.



At the same gross weight, airplane configuration, and
power setting, a given airplane will consistently stall at
the same indicated airspeed if no acceleration is
involved. The airplane will, however, stall at a higher
indicated airspeed when excessive maneuvering loads
are imposed by steep turns, pull-ups, or other abrupt
changes in its flightpath. Stalls entered from such flight
situations are called "accelerated maneuver stalls," a
term, which has no reference to the airspeeds involved.



Stalls which result from abrupt maneuvers tend to be
more rapid, or severe, than the unaccelerated stalls, and
because they occur at higher-than-normal airspeeds,
and/or may occur at lower than anticipated pitch
attitudes, they may be unexpected by an inexperienced
pilot. Failure to take immediate steps toward recovery
when an accelerated stall occurs may result
in a complete loss of flight control, notably,
power-on spins.



This stall should never be practiced with wing flaps in
the extended position due to the lower "G" load
limitations in that configuration.



Accelerated maneuver stalls should not be performed
in any airplane, which is prohibited from such
maneuvers by its type certification restrictions or
Airplane Flight Manual (AFM) and/or Pilot's
Operating Handbook (POH). If they are permitted,
they should be performed with a bank of
approximately 45°, and in no case at a speed greater



than the airplane manufacturer's recommended
airspeeds or the design maneuvering speed specified
for the airplane. The design maneuvering speed is the
maximum speed at which the airplane can be stalled or
full available aerodynamic control will not exceed the
airplane's limit load factor. At or below this speed, the
airplane will usually stall before the limit load factor
can be exceeded. Those speeds must not be exceeded
because of the extremely high structural loads that are
imposed on the airplane, especially if there is
turbulence. In most cases, these stalls should be
performed at no more than 1.2 times the normal
stall speed.



The objective of demonstrating accelerated stalls is not
to develop competency in setting up the stall, but rather
to learn how they may occur and to develop the ability
to recognize such stalls immediately, and to take
prompt, effective recovery action. It is important that
recoveries are made at the first indication of a stall, or
immediately after the stall has fully developed; a
prolonged stall condition should never be allowed.



An airplane will stall during a coordinated steep turn
exactly as it does from straight flight, except that the
pitching and rolling actions tend to be more sudden. If
the airplane is slipping toward the inside of the turn at
the time the stall occurs, it tends to roll rapidly toward
the outside of the turn as the nose pitches down
because the outside wing stalls before the inside wing.
If the airplane is skidding toward the outside of the
turn, it will have a tendency to roll to the inside of the
turn because the inside wing stalls first. If the
coordination of the turn at the time of the stall is
accurate, the airplane's nose will pitch away from the
pilot just as it does in a straight flight stall, since both
wings stall simultaneously.



An accelerated stall demonstration is entered by
establishing the desired flight attitude, then smoothly,
firmly, and progressively increasing the angle of attack
until a stall occurs. Because of the rapidly changing
flight attitude, sudden stall entry, and possible loss of
altitude, it is extremely vital that the area be clear of
other aircraft and the entry altitude be adequate for safe
recovery.



This demonstration stall, as in all stalls, is
accomplished by exerting excessive back-elevator
pressure. Most frequently it would occur during
improperly executed steep turns, stall and spin
recoveries, and pullouts from steep dives. The
objectives are to determine the stall characteristics of
the airplane and develop the ability to instinctively
recover at the onset of a stall at other-than-normal stall
speed or flight attitudes. An accelerated stall, although
usually demonstrated in steep turns, may actually be
encountered any time excessive back-elevator pressure



is applied and/or the angle of attack is increased
too rapidly.



From straight-and-level flight at maneuvering speed
or less, the airplane should be rolled into a steep level
flight turn and back-elevator pressure gradually
applied. After the turn and bank are established,
back-elevator pressure should be smoothly and
steadily increased. The resulting apparent centrifugal
force will push the pilot's body down in the seat,
increase the wing loading, and decrease the airspeed.
After the airspeed reaches the design maneuvering
speed or within 20 knots above the unaccelerated stall
speed, back-elevator pressure should be firmly
increased until a definite stall occurs. These speed
restrictions must be observed to prevent exceeding the
load limit of the airplane.



When the airplane stalls, recovery should be made
promptly, by releasing sufficient back-elevator
pressure and increasing power to reduce the angle of
attack. If an uncoordinated turn is made, one wing may
tend to drop suddenly, causing the airplane to roll in
that direction. If this occurs, the excessive back-
elevator pressure must be released, power added, and
the airplane returned to straight-and-level flight with
coordinated control pressure.



The pilot should recognize when the stall is imminent
and take prompt action to prevent a completely stalled
condition. It is imperative that a prolonged stall,
excessive airspeed, excessive loss of altitude, or spin
be avoided.

Friday, February 13, 2009

Takeoff Roll - Ground Effect On Takeoff


Taking off from a short field requires the takeoff to be
started from the very beginning of the takeoff area. At
this point, the airplane is aligned with the intended
takeoff path. If the airplane manufacturer recommends
the use of flaps, they should be extended the proper
amount before starting the takeoff roll. This permits
the pilot to give full attention to the proper technique
and the airplane's performance throughout the takeoff.



Some authorities prefer to hold the brakes until the
maximum obtainable engine r.p.m. is achieved before
allowing the airplane to begin its takeoff run. However,
it has not been established that this procedure will
result in a shorter takeoff run in all light single-engine
airplanes. Takeoff power should be applied smoothly
and continuously—without hesitation—to accelerate
the airplane as rapidly as possible. The airplane should
be allowed to roll with its full weight on the main
wheels and accelerated to the lift-off speed. As the
takeoff roll progresses, the airplane's pitch attitude and
angle of attack should be adjusted to that which results
in the minimum amount of drag and the quickest acceleration. In nosewheel-type airplanes, this will involve
little use of the elevator control, since the airplane is
already in a low drag attitude.

Secondary Stall


This stall is called a secondary stall since it may occur
after a recovery from a preceding stall. It is caused by
attempting to hasten the completion of a stall recovery
before the airplane has regained sufficient flying
speed. Secondary stall.
When this stall occurs, the
back-elevator pressure should again be released just as
in a normal stall recovery. When sufficient airspeed
has been regained, the airplane can then be returned to
straight-and-level flight.



This stall usually occurs when the pilot uses abrupt
control input to return to straight-and-level flight after
a stall or spin recovery. It also occurs when the pilot
fails to reduce the angle of attack sufficiently during
stall recovery by not lowering pitch attitude
sufficiently, or by attempting to break the stall by using
power only.

Thursday, February 12, 2009

Short-Field Takeoff And Maximum Performance Climb


Takeoffs and climbs from fields where the takeoff area
is short or the available takeoff area is restricted by
obstructions require that the pilot operate the airplane
at the limit of its takeoff performance capabilities. To
depart from such an area safely, the pilot must exercise
positive and precise control of airplane attitude and
airspeed so that takeoff and climb performance results
in the shortest ground roll and the steepest angle of
climb. Short-field takeoff



The achieved result should be consistent with the
performance section of the FAA-approved Airplane
Flight Manual and/or Pilot's Operating Handbook
(AFM/POH). In all cases, the power setting, flap
setting, airspeed, and procedures prescribed by the
airplane's manufacturer should be followed.



In order to accomplish a maximum performance takeoff safely, the pilot must have adequate knowledge in
the use and effectiveness of the best angle-of-climb
speed (VX) and the best rate-of-climb speed (VY) for
the specific make and model of airplane being flown.



The speed for VX is that which will result in the
greatest gain in altitude for a given distance over the
ground. It is usually slightly less than VY which provides the greatest gain in altitude per unit of time.
The specific speeds to be used for a given airplane
are stated in the FAA-approved AFM/POH. It should
be emphasized that in some airplanes, a deviation of
5 knots from the recommended speed will result in a
significant reduction in climb performance.
Therefore, precise control of airspeed has an important bearing on the successful execution as well as
the safety of the maneuver.

Full Stalls Power-On


Power-on stall recoveries are practiced from straight
climbs, and climbing turns with 15 to 20° banks, to
simulate an accidental stall occurring during takeoffs
and climbs. Airplanes equipped with flaps and/or
retractable landing gear should normally be in the
takeoff configuration; however, power-on stalls should
also be practiced with the airplane in a clean
configuration (flaps and/or gear retracted) as in
departure and normal climbs.



After establishing the takeoff or climb configuration,
the airplane should be slowed to the normal lift-off
speed while clearing the area for other air traffic.
When the desired speed is attained, the power should
be set at takeoff power for the takeoff stall or the
recommended climb power for the departure stall
while establishing a climb attitude. The purpose of
reducing the airspeed to lift-off airspeed before the
throttle is advanced to the recommended setting is to
avoid an excessively steep nose-up attitude for a long
period before the airplane stalls.



After the climb attitude is established, the nose is then
brought smoothly upward to an attitude obviously
impossible for the airplane to maintain and is held at
that attitude until the full stall occurs. In most
airplanes, after attaining the stalling attitude, the
elevator control must be moved progressively further
back as the airspeed decreases until, at the full stall, it
will have reached its limit and cannot be moved back
any farther.



Recovery from the stall should be accomplished by
immediately reducing the angle of attack by positively



releasing back-elevator pressure and, in the case of a
departure stall, smoothly advancing the throttle to
maximum allowable power. In this case, since the
throttle is already at the climb power setting, the addition of power will be relatively slight. Power-on stall.



The nose should be lowered as necessary to regain
flying speed with the minimum loss of altitude and
then raised to climb attitude. Then, the airplane should
be returned to the normal straight-and-level flight attitude, and when in normal level flight, the throttle
should be returned to cruise power setting. The pilot
must recognize instantly when the stall has occurred
and take prompt action to prevent a prolonged stalled
condition.

Wednesday, February 11, 2009

Ground Effect On Takeoff


Ground effect is a condition of improved performance encountered when the airplane is operating
very close to the ground. Ground effect can be
detected and measured up to an altitude equal to one
wingspan above the surface. Takeoff in ground effect area
However,
ground effect is most significant when the airplane
(especially a low-wing airplane) is maintaining a
constant attitude at low airspeed at low altitude (for
example, during takeoff when the airplane lifts off
and accelerates to climb speed, and during the landing flare before touchdown).



When the wing is under the influence of ground effect,
there is a reduction in upwash, downwash, and wingtip
vortices. As a result of the reduced wingtip vortices,
induced drag is reduced. When the wing is at a height
equal to one-fourth the span, the reduction in induced
drag is about 25 percent, and when the wing is at a
height equal to one-tenth the span, the reduction in
induced drag is about 50 percent. At high speeds where
parasite drag dominates, induced drag is a small part of
the total drag. Consequently, the effects of ground effect
are of greater concern during takeoff and landing.



On takeoff, the takeoff roll, lift-off, and the beginning
of the initial climb are accomplished in the ground
effect area. The ground effect causes local increases in
static pressure, which cause the airspeed indicator and
altimeter to indicate slightly less than they should, and
usually results in the vertical speed indicator indicating a descent. As the airplane lifts off and climbs out of
the ground effect area, however, the following will
occur.



  • The airplane will require an increase in angle of
    attack to maintain the same lift coefficient.

  • The airplane will experience an increase in
    induced drag and thrust required.

  • The airplane will experience a pitch-up tendency
    and will require less elevator travel because of an
    increase in downwash at the horizontal tail.


  • The airplane will experience a reduction in static
    source pressure as it leaves the ground effect area
    and a corresponding increase in indicated airspeed.




Due to the reduced drag in ground effect, the airplane
may seem to be able to take off below the recommended airspeed. However, as the airplane rises out of
ground effect with an insufficient airspeed, initial
climb performance may prove to be marginal because
of the increased drag. Under conditions of high-density altitude, high temperature, and/or maximum gross
weight, the airplane may be able to become airborne at
an insufficient airspeed, but unable to climb out of
ground effect. Consequently, the airplane may not be
able to clear obstructions, or may settle back on the
runway. The point to remember is that additional
power is required to compensate for increases in drag
that occur as an airplane leaves ground effect. But during an initial climb, the engine is already developing
maximum power. The only alternative is to lower pitch
attitude to gain additional airspeed, which will result in
inevitable altitude loss. Therefore, under marginal conditions, it is important that the airplane takes off at the
recommended speed that will provide adequate initial
climb performance.



Ground effect is important to normal flight operations.
If the runway is long enough, or if no obstacles exist,
ground effect can be used to an advantage by using the
reduced drag to improve initial acceleration.
Additionally, the procedure for takeoff from unsatisfactory surfaces is to take as much weight on the wings
as possible during the ground run, and to lift off with
the aid of ground effect before true flying speed is
attained. It is then necessary to reduce the angle of
attack to attain normal airspeed before attempting to
fly away from the ground effect area.

Full Stalls Power-Off


The practice of power-off stalls is usually performed
with normal landing approach conditions in simulation

of an accidental stall occurring during landing
approaches. Airplanes equipped with flaps and/or
retractable landing gear should be in the landing
configuration. Airspeed in excess of the normal
approach speed should not be carried into a stall entry
since it could result in an abnormally nose-high
attitude. Before executing these practice stalls, the
pilot must be sure the area is clear of other air traffic.



After extending the landing gear, applying carburetor
heat (if applicable), and retarding the throttle to idle
(or normal approach power), the airplane should be
held at a constant altitude in level flight until the
airspeed decelerates to that of a normal approach. The
airplane should then be smoothly nosed down into the
normal approach attitude to maintain that airspeed.
Wing flaps should be extended and pitch attitude
adjusted to maintain the airspeed.



When the approach attitude and airspeed have
stabilized, the airplane's nose should be smoothly
raised to an attitude that will induce a stall. Directional
control should be maintained with the rudder, the
wings held level by use of the ailerons, and a constant-
pitch attitude maintained with the elevator until the
stall occurs. The stall will be recognized by clues, such
as full up-elevator, high descent rate, uncontrollable
nosedown pitching, and possible buffeting.



Recovering from the stall should be accomplished by
reducing the angle of attack, releasing back-elevator
pressure, and advancing the throttle to maximum
allowable power. Right rudder pressure is necessary to
overcome the engine torque effects as power is
advanced and the nose is being lowered. Power-off stall and recovery.



The nose should be lowered as necessary to regain
flying speed and returned to straight-and-level flight


attitude. After establishing a positive rate of climb, the
flaps and landing gear are retracted, as necessary, and
when in level flight, the throttle should be returned to
cruise power setting. After recovery is complete, a climb
or go-around procedure should be initiated, as the situation dictates, to assure a minimum loss of altitude.



Recovery from power-off stalls should also be
practiced from shallow banked turns to simulate an
inadvertent stall during a turn from base leg to final
approach. During the practice of these stalls, care
should be taken that the turn continues at a uniform
rate until the complete stall occurs. If the power-off
turn is not properly coordinated while approaching the
stall, wallowing may result when the stall occurs. If the
airplane is in a slip, the outer wing may stall first and
whip downward abruptly. This does not affect the
recovery procedure in any way; the angle of attack
must be reduced, the heading maintained, and the
wings leveled by coordinated use of the controls. In
the practice of turning stalls, no attempt should be
made to stall the airplane on a predetermined heading.
However, to simulate a turn from base to final
approach, the stall normally should be made to occur
within a heading change of approximately 90°.



After the stall occurs, the recovery should be made
straight ahead with minimum loss of altitude, and
accomplished in accordance with the recovery
procedure discussed earlier.



Recoveries from power-off stalls should be
accomplished both with, and without, the addition of
power, and may be initiated either just after the stall
occurs, or after the nose has pitched down through the
level flight attitude.