Unicom: 06/04


Lancair vs. Cirrus
In your article on Cirrus safety record, you say there has yet to be an accident involving a U.S. registered Lancair Columbia. We can think of one, the 1999 crash of N141LC.

-Rae Willis
Morristown, N.J.

Well, it was and it wasnt. That crash involved a non-conforming prototype and, although it did occur after Lancair had received certification for the design, we aim to include only real airplanes flown in a real world manner. For that reason, we also did not include the crash of another Lancair during spin test training when the spin chute would not release.

The accident you cite is a unique case because it involved a factory test pilot with limited instrument experience flying it on an instrument approach. The lack of conformity may have played a role in the operation of the airplane during the approach, but theres no way to know because of the limited recovery of the wreckage. We could just as easily have included it.


Yeagers Fender-bender
I have just read the letter in which the writer stated he was outraged that you would mention Yeagers name in your recounting of this accident report [Unicom, March]. I think I understand why he feels that revealing Yeagers name might be embarrassing, but I disagree with his conclusion.

The fact that an experienced guy like Yeager can have difficulties landing a T-6 with a quartering tailwind on a narrow strip in a borrowed airplane only highlights the fact that it could have happened to anyone.

I am not sure, but I would bet Gen. Yeager has not had very much flight time in T-6s recently and when folks are not really familiar with an aircraft they typically fly an approach faster than necessary. My guess is that Gen. Yeager flew a 100-knot final with a slightly gusty quartering tailwind and the rest is history.

It would be great if he would tell us what he feels the cause of his departure from the runway was. I also understand the terrain sloped downhill from the runway to a culvert at this private airport. Perhaps if he had had the normal flat safety areas, he would just have run uneventfully in the grass and returned to the runway.

In my view, it was helpful to know that it was Yeager who had the difficulty, because his lesson teaches the rest of us not to be complacent. This type of landing incident is the single most prevalent accident in T-6 aircraft and is usually accompanied by an 8- to 14-knot crosswind.

By the way, I have 2200 hours in the T-6, which I fly nearly every day for a living, and I have the utmost respect for Gen. Yeager and the T-6.

-Mark Hutchins
Via e-mail


ALARMing Developments
My engine-out emergency procedures mnemonic is ALARMS, as in Oh no, my engine conked out, so sound the alarms!

Airspeed (best glide), Landing (where?), Attempt restart (use checklist), Reduce RPM (for complex airplanes), Mayday (tune 121.7 and squawk 7700), Secure (engine, fuel, occupants, cabin).

In my opinion, its a lot better than the ABC example described in No Engine Approach [Instrument Check, January]. Besides, the ABC mnemonic is already reserved for medical emergencies: Airway, Breathing, Circulation.

-David Breznick
Iron Mountain, Mich.

You left out a fundamental first, middle and last step: Fly the airplane.


Any information as to what GPS not reliable really means? I frequently fly from Northern California to Santa Fe, N.Mex., by way of PMD and northern Arizona. An all too frequent Notam is that GPS is unreliable for very large areas of operation around the Naval Weapons base at China Lake in California.

I am a VFR-only pilot; however, my airplane is equipped with two in-panel GPS receivers and I have a portable (196) backup. I do always keep the VOR/DME equipment tuned in to the appropriate stations for the airways I am using and there is the sectional on my knee with appropriate course lines duly plotted.

Are the displacements being generated to disrupt the GPS signals such that they are unreliable for instrument approaches only or am I going to see that my GPS shows me over Denver when I can clearly see Palmdale?

Its interesting to note that usually these Notams are for periods during the week and not on the weekend (out of consideration for general aviation pilots?). However, since I am somewhat retired (it turns out I have to work to feed the plane) I really do like to fly during the week and avoid practicing collision avoidance at popular destinations on the weekends.

Any input on this?

-Jerry Warman
Via e-mail

Sounds like youre a careful pilot, with good redundancy. The FAAs Aeronautical InformationManual (AIM) has this to say about a Notam stating GPS UNRELIABLE:

The term UNRELIABLE is used in conjunction with GPS NOTAMs. The term UNRELIABLE is an advisory to pilots indicating the expected level of service may not be available. GPS operation may be NOTAMed UNRELIABLE due to testing or anomalies. Air Traffic Control will advise pilots requesting a GPS or RNAV (GPS) approach of GPS UNRELIABLE for: a) NOTAMs not contained in the ATIS broadcast. (b) Pilot reports of GPS anomalies received within the preceding 15 minutes.

In addition to Notams, the FAA maintains a Web page dedicated to tracking GPS outages. Its at

What the DoD is doing at China Lake and at other locations around the country anyones guess. Conventional wisdom is that they are conducting jamming tests, but GPS has been around long enough that youd think theyd have exhausted the possibilities by now.

Note that these Notams arent directly related to the RAIM (Receiver Autonomous Integrity Monitoring) alerts your GPS receiver may display from time to time. However, if experimental jamming is aimed at a particular satellites code-we dont if DoD can do that or not-you might see a RAIM alert.


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