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  #11  
Old 01-10-2018, 06:19 PM
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snopercod snopercod is offline
 
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I have an AFS "Sport" AoA. It's a stand-alone unit with a small .040" port on the top of the outboard wing and another on the underside. I mounted the LED bar graph display immediately to the left of my ASI so it's in my peripheral vision while landing. In a Lancair, it's a must-have safety device:

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  #12  
Old 01-11-2018, 04:20 AM
svyolo svyolo is offline
 
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Location: bellingham, wa
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Default

I am a former Naval Aviator as well (USMC side). We were talk to fly AOA as a performance instrument, not just safety. I always thought it was a better way to fly, but old school electromechanical AOA was expensive and not that reliable.
I have been flying part 121 for over 20 years. They come up will all kinds of god awful cards for different V speeds and approach speeds because of the huge weight range of jets. In reality, you are simply flying AOA, using airspeed as the primary reference.

If you have an EFIS, you already have a pretty good IRS based AOA. The vertical difference between the nose of the airplane, and the velocity vector (flight path marker) as measured on the PFD, is your AOA. I use it all the time in the simulator. When they give me failed or unreliable airspeed in the sim, I just fly AOA. They can't figure out how I do it because they were not trained to do it.

But I will install an AOA above the glare shield on the plane I am building.
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  #13  
Old 01-11-2018, 05:12 AM
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rv8ch rv8ch is online now
 
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Default Synthetic vs. measured AOA

It would be great of one of you test pilots would compare Synthetic vs. measured AOA under various circumstances to see if I can avoid the plumbing required for a measured AoA.
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  #14  
Old 01-11-2018, 06:09 AM
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f14av8r f14av8r is offline
 
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Location: Tampa (Wimauma actually)
Posts: 429
Default Use the tone

I installed the Dynon AOA in my -4. Had to pull the left tank and install the new probe, wiring, and pitot / static lines. I put the heater module on the inside of the access panel but mounted the probe in the skin against the rib.

AOA is a very important tool and the ability to install it relatively cheaply in our experimental airplanes makes it a slam dunk. Just do it, you won't regret it.

As others have mentioned, having a display in your line of sight is helpful but only if that means while you are looking outside. Don't worry about the display. I almost never look at mine on the Skyview. Just set up the tones properly and you listen to those for AOA while keeping your scan primarily out the window.

I find AOA most useful in the landing pattern but it provides some benefit during aerobatics as well.
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  #15  
Old 01-11-2018, 09:43 AM
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Ironflight Ironflight is offline
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Quote:
Originally Posted by rv8ch View Post
It would be great of one of you test pilots would compare Synthetic vs. measured AOA under various circumstances to see if I can avoid the plumbing required for a measured AoA.
Did that years ago....bottom line is that they compare well for things like approaches, where bank angle is low and things aren't;t changing rapidly. During heavy maneuvering, with all axes changing rapidly, synthetic can get lost.

Paul
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  #16  
Old 01-11-2018, 10:02 AM
bpattonsoa bpattonsoa is offline
 
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I have dual Dynon Skyviews in my -10. It has the AOA display, but is almost useless. It is a tiny wiget on the screen and you definitely do not want to look for it in the pattern. The audio is good, but not a great.

I have suggested the following to Dynon and have been ignored to date.

At a user selected airspeed, say 90 knots for my -10, have the program expand the AOA wiget to the size of the airspeed tape and put it just to the right of the tape.

Now it is easy to find and of a size that can be seen at a glance when you mostly need it. If you want it all the time, just set the airspeed selection to a high number.
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  #17  
Old 01-11-2018, 01:10 PM
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rv8ch rv8ch is online now
 
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Default Synthetic vs. measured AOA

Quote:
Originally Posted by Ironflight View Post
Did that years ago....bottom line is that they compare well for things like approaches, where bank angle is low and things aren't;t changing rapidly. During heavy maneuvering, with all axes changing rapidly, synthetic can get lost.
Thanks Paul - sounds like you recommend installing the measured AOA, which I will do.
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  #18  
Old 01-13-2018, 10:30 PM
jay bell jay bell is offline
 
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I ordered my Dynon with AOA after reading how carrier pilots use it, and getting to ride right seat with a fellow RV'er in his day-job machine; a Lear 45. After he explained Mach stall and the unfamiliar gauges and controls, I asked "where is your airspeed indicator?" He chuckled, and said "don't need one, the GPS tells how fast you are going, the Mach gauge tells you not to to go too fast, and the AOA tells you not to go too slow". "But the rules say you need one!" I protested. "Oh that" he said, and opened a little cubby with emergency gauges such as airspeed, compass, and gyro horizon. "Never had to use them for real, and pray I never do" he replied.

The Dynon AOA installed easily with two plastic lines coming from the wing mounted pitot; no more difficult than routing a single line behind the wing tank and back to the ADAHRS in the fuselage. It was also easy to calibrate, just sneak up on a stall at altitude, and press a button at the break.

I don't like the Dynon AOA display, it is too faint, and too low on the panel to look at on short final. However, after a year of flying fast approaches I hooked up the audio signal to my intercom and wow, what an amazing device! It uses variable frequency beeps to provide AOA feedback for approach, landing, aerobatics, and canyon turns. The steady warning tone always comes on just before stalling for fun, no matter what airspeed, flap setting, or orientation the plane has. It helps me come in slow when visiting my friend's farm strip lightly loaded, and reminds me that the safe IAS for approaching hot and heavy is about 25 knots faster. I can't imagine how I could accidentally stall while the device is working properly, and because of the feedback, I have a better sense of lift even without instruments. (I lost pitot and AOA pressure twice, once by hitting a big bug, and once in VMC snow without pitot heat - my bad)

This is the only AOA I have used, so I don't have an opinion as to which brand is best. Like a previous post said, the device needs to readily visible or audible, or it won't do any good when you need it most.

Jay
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  #19  
Old 01-14-2018, 07:22 AM
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Beagle Beagle is offline
 
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Default Convinced

Thanks Gents,
After reading these posts I am convinced to install an AOA. I love this site!
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  #20  
Old 01-14-2018, 07:57 AM
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f14av8r f14av8r is offline
 
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Quote:
Originally Posted by jay bell View Post
I ordered my Dynon with AOA after reading how carrier pilots use it, and getting to ride right seat with a fellow RV'er in his day-job machine; a Lear 45. After he explained Mach stall and the unfamiliar gauges and controls, I asked "where is your airspeed indicator?" He chuckled, and said "don't need one, the GPS tells how fast you are going, the Mach gauge tells you not to to go too fast, and the AOA tells you not to go too slow". "But the rules say you need one!" I protested. "Oh that" he said, and opened a little cubby with emergency gauges such as airspeed, compass, and gyro horizon. "Never had to use them for real, and pray I never do" he replied.

The Dynon AOA installed easily with two plastic lines coming from the wing mounted pitot; no more difficult than routing a single line behind the wing tank and back to the ADAHRS in the fuselage. It was also easy to calibrate, just sneak up on a stall at altitude, and press a button at the break.

I don't like the Dynon AOA display, it is too faint, and too low on the panel to look at on short final. However, after a year of flying fast approaches I hooked up the audio signal to my intercom and wow, what an amazing device! It uses variable frequency beeps to provide AOA feedback for approach, landing, aerobatics, and canyon turns. The steady warning tone always comes on just before stalling for fun, no matter what airspeed, flap setting, or orientation the plane has. It helps me come in slow when visiting my friend's farm strip lightly loaded, and reminds me that the safe IAS for approaching hot and heavy is about 25 knots faster. I can't imagine how I could accidentally stall while the device is working properly, and because of the feedback, I have a better sense of lift even without instruments. (I lost pitot and AOA pressure twice, once by hitting a big bug, and once in VMC snow without pitot heat - my bad)

This is the only AOA I have used, so I don't have an opinion as to which brand is best. Like a previous post said, the device needs to readily visible or audible, or it won't do any good when you need it most.

Jay
Nice writeup Jay. The AOA tones are definitely the best way to fly the airplane. And, as you note, the beauty of AOA is that you don't have to calculate a stall speed. The aircraft ALWAYS stalls at the same angle of attack. The airspeed may vary greatly depending on many factors but the AOA will always be the same. When that tone goes solid, the airplane is going to stall. It's a great tool!
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