.
June 2015 from Don Kaye, a Master CFI:
Not trying to brag here, but based on the number of students I've trained over the past 21 years I would estimate that I have done somewhere in the vicinity of 20,000 landings based on about 30-50 per student checkout. Bottom line: I'm pretty good at landings.
Still, I like the AoA. For example, in the past, depending on weight my airplane has an approach speed than can vary as much as 15 knots. Approaching 5 knots too fast is too fast with the Mooney wing. If I could stall the airplane each time before an approach then the AoA wouldn't be that important. For 20 years, on any long trip I would weigh everything and knowing the empty weight of the airplane would always know what the zero fuel weight was. I would do a quick calculation based on fuel remaining what the landing weight was. The rule of thumb was to reduce the nominal approach speed by 5 knots for every 300 pounds under gross I was. That worked pretty well, but there was always a cushion left.
I bought the AlphaSystemsAoA as a test to see if it would be useful. I really didn't expect much from it. I calibrated it very accurately flaps down at 1.3 Vso on the low end and flaps up at the top of the white airspeed arc at the high end.
After a couple of months of use I found that based on the donut, I was using approach speeds that were nearly 5 knots slower than I had been using, didn't waste the time on pre-landing computations, and obviously the landing distances were shorter. With the laminar flow wing of the Mooney the backside of the power curve is steeper than that of the wing of a non laminar flow airplane, so you really want to be careful how far up that backside you are operating. The AoA allows operation farther up that curve than I would have been comfortable pre-AoA.
Thus landing with no headwind component at about a 6° slope with 2,200 feet of useful runway at Sonoma Skypark this week proved to be no sweat with the use of the AoA.
I recommend the AoA display as being a very useful tool for landing, takeoff, climb, glide at any variation of CG or weight without wasting any energy on mental calculations. Don Kaye, MCFI
Late 2011... Rick Ott (BE36TN, Columbia SC) on BeechTalk:
If you are a disciplined pilot flying consistent weights and conditions, then [an AoA sensor/display] may not be necessary. I survived for thousands of hours without one. I installed the Alpha System AoA in my '79 A36 for a couple of reasons. First is that my bride and daughter are learning to fly and eventually they will be in the A36. Second reason is that this airplane is flown at and near Max Gross Weight. I baby this aircraft and want landing speeds at close to stall as possible. Also maneuvering at higher weights is different than at lower weights. Stall speed is affected by weight. I am still learning to use this device but I would spend the money again. It gives a visual indication of where this aircraft is relative to stall regardless of weight....if you are a infrequent flyer (less than 200 hours per year) or flying into shorter strips, then I'd recommend installing an AoA.
John Fulton S35 Bonanza, Tucson, AZ Aircraft: S35 Another vote for Alpha AoA. I agree with Rick's thoughts above. My limited experience [with the 4 inch LED version] so far is this, it enables ... no, let me change that ... it makes precision easier, it removes grey areas of doubt you might be having about that base to final turn and anything else. and IMHO adds a lot of safety margin in all phases of flight for about the cost (installed) of a portable gps. No 337 required, minor alteration, at least mine was.
Scott Newpower is an ATC Tower controller  in Billings MT and flies his S35 Bonanza into : "To me the type of AoA display to get depends on what you are going to use it for. There seem to be two uses. If you want a device that helps you keep a healthy margin above stall at all times, ie: you are not interested in getting all that close to a stall, then the electronic models are for you.
I don't want that. I want to be able to get right up next to the stall when I choose to for short and soft field work. To me the models with the analog needle work best for that, if you calibrate it so you can easily read where the stall is....As one who flys at the low speed end  of the envelope a lot, I hace set my AoA differently than the manual calls for. The manual calls for you to slow down in a clean configuration, keep the plane level and the needle should get to its optimum angle of attack at minimum controllable airspeed in this clean configuration. I see little use to this information. I am adjusting mine so the stall is indicated at the "Greek Alpha" symbol, which is the line between the yellow and red region, seen here:
Keith Hale, G36 Dublin VA: I have the Alpha Legacy AoA system and give it a big thumbup!
Adam Priest, A36 Knoxville TN KDXX: "I have the Alpha Legacy also. If you have a Legacy AoA, calibrating is pretty simple. If I can figure it out, anyone can. I love the AoA indicator. It is very intuitive and easy to use. I would recommend it. I see Scott's point about people who regularly fly on the edge of the envelope wanting exact precision in their AoA indicator. The Legacy works for me as I rarely fly like Scott does. We programmed our Legacy AoA right between where Scott Newpower has his and Fred has the King Air set. Our green donut is set a bit below approach speed where Fred seems to have his donut set closer to normal approach speed. What this gives us is no green donut on approach until we get closer to landing. We get a half donut or yellow bars on approach.
Fred (your host here, King Air 90) inserts: "Adam, I fly an instrument approach procedure at 120KIAS, and will slow to ~100KIAS as we get to the last mile, finally slowing to the donut at minimums. My donut is set for 90~95 and that is ~1.3Vso. That seems very close to what you seem to have configured yours to do."
Brian Cantrell, a former Naval Aviator, N35 Bonanza Memphis TN: "I have the Alpha system as well. I have the older style 4" horizontal LED light bar. I was considering the analog gauge initially, mainly for simplicity and price. I just happened to have a neighbor that bought this unit for his Glasair, but later decided not to install it due to issues with plumbing the lines through his wings. I basically ended up getting the LED unit for the analog price. My unit does not have the audio capability, but I really didn't want it. I find that it's plenty precise for me. Once properly calibrated, it takes the guesswork out of spot/short landings and airspeed control on final. I don't have the tight mountain strip experience that Scott does, but I do have a couple hundred carrier landings. I felt kinda naked trying to land on a short cropduster strip near my parents house before I had the AoA. Now I know exactly how much energy I have throughout the approach. It's much more comfortable for me - and safer.
Lee Wenninger A36TN, Charlotte NC: Another vote for Alpha Systems AoA. I have one of their new 'Enhanced Ultra' electronic versions and highly suggest the enhanced option if you go the electronic route. It adds aural warnings and much improved display logic for the 16 LED models. My understanding is that whether its a Major Alteration requiring a Form 337, or is a Minor Alteration, depends on the aircraft and how it is installed. [EDITOR: Exactly so; see this link]. Mine was done as a minor alteration, and there is quite a lot of precedent and FSDO support for this being done as a minor alteration.
Joe Sasser, Pecan Plantation TX, We finally got my Apha Systems Legacy AoA installed in my Bonanza and I have about a month and 20 hours flying with it. After having AoA in most all of the aircraft I flew in my day job for 40 years [corporate jets, worldwide] and not having AoA in the personal aircraft I flew all those years and having felt so many times like I was missing a valuable tool in my own aircaft... it sure feels good to have my AoA back...!
Newpower again: "I can see either unit being a good teaching tool. What I'd like to see is folks invest similar time in flying slow for practice that they do shooting approaches. ... For folks who just want to know at a glance by a green light/doughnut/chevron that they are OK the electronic units are hard to beat.
Pat Groves and Jack Doyle own an E55 Baron with Colemill winglets and VGs in San Carlos CA: "We set the OAA to be 81KIAS. We picked that because we wanted to have a Vref of 1.3Vso. The documentation with the VG kit said that the Vso would be 62KIAS. We have confirmed that number in flight. Since 1.3 x 62 = 80.6, we set the OAA [the donut] to be 81KIAS. Subsequent flight test have shown that to be a comfortable number with complete aileron and elevator control at that speed.
HUGELY IMPORTANT!
June 2015--in the , the FAA is making a big push to get AoA indicators installed in General Aviation aircraft.
Read the full FAA inFO document here.
Earlier, in its extraordinarily helpful December 2011 FAA clarification letter, the FAA Small Aircraft Directorate explains that installation is a "minor alteration" on the vast majority of light general aviation aircraft.
Recently-published magazine articles, Spring & Summer 2011
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