Thorp Air Command - T18.net

How many people have an angle of attack (AOA) indicator installed on their plane?

It never ceases to amaze me that we as an aviation world still kill ourselves on a consisten basis with the classic stall/spin scenerio. All of which or most of which can now be eliminated with an AOA indicator and warning. I have been in wonderment that we know that the stall ALWAYS occurs at the same critical angle of attack. Yet the stall can occur at any speed or attitude given the weight, load factor etc. And yet the FAA to this day does not require an AOA to be installed on the hugely expensive new airplanes like the Pipers and Cessna's etc. Like a couple hundred dollar life saving equipment will deterr a buyer of a new Half Million Dollar aircraft!

Anyhow with low and slow being something that it seems most think is not a good place for a T-18 to be (or any airplane for that matter), it would seem with all the available AOA indicators out there today that it would make sense to install one on a T-18 as an added measure of safety in addition to stall strips etc.

So I was just wondering if anybody other than the one I read here with the Dynon system and a elbow installed on the bottom of the fuselage.

If people have, which unit did they install and how does it work? Would you recommend an AOA?

Just curious.

Not too many, apparently. I intend to install one on the racer.
Cubes

I've got one.

Jim

Here is a thread on the topic...

viewtopic.php?f=8&t=7584&p=11493&hilit=AOA#p11493

There seems to be too many advantages of an AOA to not install one. Not just safety but accuracy in approach glide path and minimizing float and ground roll ect for those folks who are operating on shorter rwys.

I find them to be distracting, especially the ones with the voice (bitch) option.

_________________
Bob Highley
N711SH
SN 835
KLAL

No voice on mine. It is a simple home made system based on a diferential pressure gauge.

Jim

C'mon Bob, we lived on them in the AF.
Cubes

I like mine, but I find it's not very useful during landings because of the small size and location of the AOA display on the Dynon D100 unit. I do get the voice, which does distract me during landing. I will get used to the voice I hope.

When practicing stalls I do look at the AOA indicator to check its accuracy, and it is spot on.

I wish I had one to put on my glareshield.

I'm with Bob.

_________________
John Evens
Arvada, Colorado
T-18 N71JE (sold)
Kitfox 7 SS N27JE

Most of the ones I've seen have a series of arrows or LED lights or an analog guage. I guess the planes with the EFIS dispaly computers etc may have a voice options. But I would think that those could be tailored to say what you want or to shut off the voice alarm.

I would think the AOA's that are series of lights would be non intrusive and WAY, WAY more accurate and every bit as quick of a reference than an airspeed indicator which really tells you exactly NOTHING as to who close you may or may not be to a stall.


All of the military, airlines and the corporate aircraft all use extensively AOA's. Why does it seem so taboo in small GA? Especially since the stall/pin accidents are I think the #2 killer in small General aviation. I for one am tired of these repeat accidents happening over and over and killing people each time giving small aviation a bad reputation as being dangerous. Now that we have what appears to be pretty affordable AOA's which has the potential to dramatically cut down on these deaths.

I guess each person has to make their own decision. And even the FAA recently made AOA indicator installations a logbook entery as they are now seeing the logic that getting AOA's into more aircraft as a safety aspect and make it easier to install in certified aircraft without having to get a STC or even a 337.

I guess I am surprised that not as many T18 owners have not installed or were even thining about installing AOA indicators. I would have guess that the high performance pilots for T18's etc would be all over having AOA's as time and again I've read that you do not want to be low and slow in a T18 (or any high performance airplane with higher wing loading). So it would seem that AOA's would be pretty common. I guess this is just too new of technology or something.

All I can say is that if I ever build or even buy a T18/S18 I fully intend to install some sort of AOA. That is the nice thing about having your own airplane and experimental airplane to boot. It makes it pretty easy to have what we each want.

I hesitate to engage in this conversation, but I want to make it clear that I don't have anything against AOA indicators. I just think that for me they would be another distraction that I don't need. In my personal opinion we already have the capability to add so many distractions to our instrument panels, that we are frequently hearing about the potential safety issues with pilots being drawn to the panel instead of concentrating on looking outside and really "feeling" the airplane & what it's doing. I like stall strips on the Thorp, and one big advantage to them is that you don't have to look at an instrument to be warned of an approaching unsafe condition. I certainly wouldn't question anyone's choice to have an AOA indicator, and I applaud safety advances in general. I don't see it being "taboo" in general aviation aircraft at all. The basic technology is not new. What pilots want in their personal aircraft changes all the time. My point is that I don't see the need for one in my T-18. It's strictly personal. The T-18 is perfectly capable of safe "low & slow" flight - it's all relative. In an F-16, I'm sure it's a "must-have".

_________________
John Evens
Arvada, Colorado
T-18 N71JE (sold)
Kitfox 7 SS N27JE

John,
The F-16's AOA indicator is really only useful for establishing final approach airspeed, which varies greatly depending on weight and configuration. Although there is some fairly simple math to compute final approach airspeed, I always try to avoid math in public; so, it's just easier to fly 11 deg AOA on final and forget the math. It was the same in the light gray Eagle (the single-seater) and F-5. Although the MiG-29 has an AOA indicator, final approach airspeed is always 175 KIAS - simple. Max range AOA is 4 deg and max endurance is 6 deg in the Fulcrum. A whole ton of difference there. AOA indicator in the T-18? Whatever flies up your skirt I guess.

I like the idea of a glare shield mounted one. I'd like to see a display similar to the F4. Not a show stopper either way, but it does provide more info on what the wing is "thinking" vs the airspeed indicator.
Cubes

We had the glare shield mounted AOA on the A-4 and T-2 . Very simple and was easy to see in direct sunlight . As you turned into the groove coming aboard the USS Lex the only two things you were looking at were the centered "Donut" on the AOA indexer and the centered "meatball" on the lens . The problem I see with the EFIS units is being able to read the AOA in direct sunlight and having your head down looking at the EFIS when on final . There are panel mounted units , but I see the same sort of problems with them . Cubes is right , a glare shield mounted unit that can be read in direct sunlight that allows you to keep your head up and out would be my way to go . The only time I see you using an AOA indicator is on final , but this and other airplanes fly just fine w/o an AOA indicator . Surely we can keep our approach speeds +/- 5 MPH (KTS) of our targeted final approach speed...AND don't call me Surely !

If it gives you a warm and fuzzy feeling and you have the extra change to spare , then put the sucker in !

RB

115 THORP BALL 1.5