Zaon XRX LongEz Collision Avoidance

I bought the Zaon XRX for my LongEz as I read it could remote interface with the Garmin 496 which I have mounted in the front of my canopy so it's like a head-up display.

The Zaon XRX comes with leads which allow remote mounting so that it paints onto the screen of the 496 (and I beleive, the 396) with direction and relative altitude.

However, it has to be calibrated to align with the aircraft, and is designed to live on the cockpit coaming of a "normal" aircraft; the setup screen/ranges etc is visible in that mode. Initially I thought I'd mount it in the rear, on the floor. But that's not really practical as you need to get to it for various reasons, not least of which is to be able to turn it on. So I ended up mounting it on the flat part of the pilots seat back, alongside the headrest. It gives a slight background noise. On a trip from FL to CA it warned me twice before I saw the traffic (which was no conflict) so I guess it works.

When flying in formation with Richard Richmond, I had to endure an hour of warnings and a flashing red dot on the screen as if I had turned it off, I wouldn't have been able to reach to turn it back on again until getting on the ground.

So it works, although the ergonomics diminish its utility. I think that in a Cozy there would be more room to mount it on the "coaming" as intended, where it would be great.

Spektrum DX5E

I was wondering what kind of servos can be used with the Spektrum DX5E. The Spektrum servos on their website all seem to be micro foamy plane type servos, no standard size for say .40 size planes are shown. So if one is to buy this 2.4 Ghz radio / receiver, is it compatible with standard Futaba servos? A switch harness and battery pack would also be needed to complete the radio package, correct?

I think I paid about $350 for me DX7 fully loaded back in March. The TX that came with my Blade CX2 is a 5 Channel DSM probably close in features as the DX5E, no programming features though. Both have been flawless in their operation so far. Are you able to field program the DX5E?

LOAD FACTORS AND STALLING SPEEDS

Any airplane, within the limits of its structure, may be stalled at any airspeed. When a sufficiently high angle of attack is imposed, the smooth flow of air over an airfoil breaks up and separates, producing an abrupt change of flight characteristics and a sudden loss of lift, which results in a stall.

A study of this effect has revealed that the airplane’s stalling speed increases in proportion to the square root of the load factor. This means that an airplane with a normal unaccelerated stalling speed of 50 knots can be stalled at 100 knots by inducing a load factor of 4 G’s. If it were possible for this airplane to withstand a load factor of 9, it could be stalled at a speed of 150 knots. Therefore, a competent pilot should be aware of the following:


The danger of inadvertently stalling the airplane by increasing the load factor, as in a steep turn or spiral; and
That in intentionally stalling an airplane above its design maneuvering speed, a tremendous load factor is imposed.

Reference to the charts in figures 3-36 and 3-37 will show that by banking the airplane to just beyond 72° in a steep turn produces a load factor of 3, and the stalling speed is increased significantly. If this turn is made in an airplane with a normal unaccelerated stalling speed of 45 knots, the airspeed must be kept above 75 knots to prevent inducing a stall. A similar effect is experienced in a quick pullup, or any maneuver producing load factors above 1 G. This has been the cause of accidents resulting from a sudden, unexpected loss of control, particularly in a steep turn or abrupt application of the back elevator control near the ground.

Since the load factor squares as the stalling speed doubles, it may be realized that tremendous loads may be imposed on structures by stalling an airplane at relatively high airspeeds.

The maximum speed at which an airplane may be stalled safely is now determined for all new designs. This speed is called the “design maneuvering speed” (VA) and is required to be entered in the FAA-approved Airplane Flight Manual or Pilot’s Operating Handbook (AFM/POH) of all recently designed airplanes. For older general aviation airplanes, this speed will be approximately 1.7 times the normal stalling speed. Thus, an older airplane which normally stalls at 60 knots must never be stalled at above 102 knots (60 knots x 1.7 = 102 knots). An airplane with a normal stalling speed of 60 knots will undergo, when stalled at 102 knots, a load factor equal to the square of the increase in speed or 2.89 G’s (1.7 x 1.7 = 2.89 G’s). (The above figures are an approximation to be considered as a guide and are not the exact answers to any set of problems. The design maneuvering speed should be determined from the particular airplane’s operating limitations when provided by the manufacturer.)

Since the leverage in the control system varies with different airplanes and some types employ “balanced” control surfaces while others do not, the pressure exerted by the pilot on the controls cannot be accepted as an index of the load factors produced in different airplanes. In most cases, load factors can be judged by the experienced pilot from the feel of seat pressure. They can also be measured by an instrument called an “accelerometer,” but since this instrument is not common in general aviation training airplanes, the development of the ability to judge load factors from the feel of their effect on the body is important. A knowledge of the principles outlined above is essential to the development of this ability to estimate load factors.

A thorough knowledge of load factors induced by varying degrees of bank, and the significance of design maneuvering speed (VA) will aid in the prevention of two of the most serious types of accidents:


Stalls from steep turns or excessive maneuvering near the ground; and
Structural failures during acrobatics or other violent maneuvers resulting from loss of control.