AoA Indicators.

[IBob]

Thank you from me too, Garfly.

 

And I'm really liking that red wool.

 

As an automation engineer working in high maintenance industries requiring maximum robustness, we do everything we can to simplify and to take unnecessary bits out.

 

So both the simplicity of this, and his reasoning, appeal to me very much.

 

(I also set up operator interfaces (screen, touchscreens) and we follow the same principals there: strip out all the unnecessary stuff, and do as much as you can to make what it's left simple & intuitive. To some degree, this is going against popular trends...but it works.)

 

 

[Kyle Communications]

I had a good look at that link Oscar sent and the kit to make it is pretty cheap. The kit is on the bakeraircraft website and the build instructions too. About 100 bucks for everything and its a neat idea what he has done with the hall effect and magnet. I think I might order one and have a play. What I like about it is it is basically mechanical not "software" inspired

 

 

[IBob]

"And I would also suggest that a bit of bent wire attached to the leading edge of the wing with a length of red knitting wool tied to it, is the paradigm against which all other angle-of-attack indicators should be judged."

 

 

I think he's got it there too. And furthermore, the way it displays...as a red line within an angle...has to be the most intuitive way to see what it is saying.

 

I am a big fan of analog readouts (even where they are digitally generated). And while led bargraphs have their place (for coarse readings), I don't much like them: by the very nature of them, they operate in a series of steps, so unless there are lots of steps, the resolution (accuracy) is poor.

 

 

[Keenaviator]

I haven't seen anyone mention 'stall stick position' yet. Stick position seems to me to be the obvious angle of attack indicator.

 

 

[IBob]

I haven't seen anyone mention 'stall stick position' yet. Stick position seems to me to be the obvious angle of attack indicator.

Unfortunately, stall occurs at different stick positions, depending on what else is going on: flaps, engine, attitude, loading etc

 

 

[facthunter]

Mentioned and qualified as to it's applicability, in my post #7 on this thread. One person ticked informative and no comments made at all. Perhaps few read my stuff. Nev

 

 

[Garfly]

And the chap in the Red-Thread video discusses stall stick position.

 

Actually this frame that's used as the YouTube icon is from the part where he's illustrating that.

 

(It's at 08:45):

 

 

He returns to the point in his concluding par: " ... the routine use of a leading edge angle-of-attack indicator will go some way towards inculcating an intuitive grasp of the relationship between the elevator position and the angle-of-attack in the approach to the stall."

 

 

[dsam]

Mentioned and qualified as to it's applicability, in my post #7 on this thread. One person ticked informative and no comments made at all. Perhaps few read my stuff. Nev

Nev, I certainly "read your stuff"... Despite my own "longish" experience, I find I can never stop learning about aviation - made much easier when hearing from experienced people such as yourself. Keep on posting Nev!

 

 

[facthunter]

Thanks for the encouragement. It's hard to work out how this comes across. I have to be careful not to confuse, so it can be a bit "laboured". You literally "never stop learning" in this game, no matter what you have done. It's a real shame when something bad happens that could have been avoided with better training. Nev

 

 

[BlurE]

I am very interested having some sort of AOA feedback, but I think it would be best if it was audible.

 

Say a slow rate of beep.......... beep........... beep starting as say 60% of critical and increasing to a solid tone just before stall. Think of a vario or reversing sensor type thing.

 

Maybe?

 

 

[Garfly]

For me, there's something else interesting in Robert Jago's 'Red-Thread' video, above (in #32) which he doesn't draw attention to. You can see right at the start, as he approaches that farm strip in his Foxbat that he flies a continuous turn from downwind to final - not the conventional rectangle.

 

That's another debate (re)doing the rounds lately and not altogether off-topic, here. After all, it's mentioned (warily) in this John Zimmerman article, along with AoA technology, as among innovations being trialled in the US in a concerted campaign against loss-of-control (LOC) accidents. (40% of all GA fatals, they say.) A broad alliance of safety orgs., Zimmerman writes, is reaching out desperately for any ideas that might reduce the carnage.

 

Searching for a miracle cure to loss of control accidents - Air Facts Journal

 

Dick Collins, in a related article, comes out clearly in favour of the circular approach among other (good) ideas such as why do we bother broadcasting our entire tail number when talking to each other at uncontrolled airports when it's likely meaningless to most. He, and others, are proposing 'Blue Bonanza One' or suchlike.

 

[Maybe that issue's good for another thread, here, no? I've noticed that the full name and number of some of our RAAus craft can run to twelve (slurred) syllables or more! (And that's before we move on to our a-ummin' and a-ahrrrin'. ;-) What RPT captain - or Cessna driver, for that matter - is gonna know what the hell a Skyranger or CH750 - plus phone number - might look like?]

 

Arriving at the VFR sweet spot - without colliding or spinning in - Air Facts Journal

 

And then, for them what believe that too many gadgets ain't never enough ;-) another new idea mentioned is The Airball. It won a big EAA Innovation prize for it's inventor in 2016.

 

Actually, I think this instrument might take care of Sam's (SDQDI) and Yenn's objections to AOA only, i.e, what about coordination?.

 

"Airball synthesizes air data from a number of sensors and graphically presents it so that a pilot can quickly understand the current flight state of the airplane. A blue ball on the display grows, shrinks, and moves around the display as airspeed, angle of attack, and yaw change. Keeping the ball the right size, and in the right place, ensures that the airplane is well outside any regime that may result in a LOCI accident."

 

 

Airball Wins

 

There ya go! Let's all play Airball!! (I trawl the net so you don't have to! ;-)

 

 

 

[Garfly]

BlurE, I think most of the recent crop of mid-range instruments do have some kind audio warning available, if you want, including beeps, horns and/or voice prompts like "Angle! Angle!" and "Too Slow!".

 

But if you had a heads-up display, do you think you'd want that as well?

 

 

[IBob]

Mentioned and qualified as to it's applicability, in my post #7 on this thread. One person ticked informative and no comments made at all. Perhaps few read my stuff. Nev

I don't think it's that, Nev. I think sometimes when we come to a thread after it is well under way, we don't necessarily go back to the start of it and read the whole thing. Or if we do, we sort of speed-read it and miss parts. I know I'm guilty at times of both those things.

 

 

[crashley]

vans have just released an AOA kit for there RV 12

 

I have already installed one

 

 

[Garfly]

Interesting. I see the new sensor kit exploits the capabilities of Dynon Skyview et al.

 

https://www.vansaircraft.com/pdf/whats_new/AOA-RV-12_Press_release.pdf

 

 

[rgmwa]

vans have just released an AOA kit for there RV 12I have already installed one

Me too. One of the smart early RV-12 builders came up with this modification a few years ago using either a rivet with the stem removed or a ball inflation valve installed as a pressure tap just below the leading edge of the wing, plus a length of flexible tubing run back to the AOA port on the Dynon ADAHRS. Very simple and only cost a few dollars for parts. Dick van Grunsven has been keen to find ways to increase the safety of experimental aircraft in recent years, and an AOA display has been seen as an important aid for pilots. It's obviously only part of the solution, but it's interesting that Vans have now released this kit, which is essentially a copy of the home-made system.

 

rgmwa

 

 

[Garfly]

Here are some Dan Johnson videos of recent Belite (Radiant) instrument offerings.

 

I guess their AoA solution is the "proper-bought-one" version of the Red-Thread Mk1.

 

 

 

[Garfly]

At the risk of coming across as a Collins family fanboy, here are some more articles I've found on the subject of AoA and its indicators. I find it interesting to read (first link) the father of Dick Collins (erstwhile editor of Flying Magazine) discussing those 'new fangled' devices back in 1965 - with a rearward glance to flying back in the '20's.

 

From the archives: Leighton Collins on angle of attack, 1965 | Air Facts Journal

 

The three keys to flying safely | Air Facts Journal

 

Airspeed vs. angle of attack - what pilots don't understand | Air Facts Journal

 

The discussion threads after these articles are often as enlightening as the original argument (just like here ;-)

 

 

[Kyle Communications]

That last article was probably the best explanation I have read on stall and speed and G...thanks for that

 

 

[Garfly]

Yeah Mark, I agree, and that guy (one Chuck Moore) has had quite an aeronautical career - as told by the blurb at the end.

 

There was some spirited debate among the aero-physicist mob (in the comments) about the accuracy of his:

 

"And if you are anything but straight and level in the air, you are not at 1G."

 

Maybe he could have saved them the bother with a 'for all intents and purposes' and still have made his main point.

 

I did notice a slip-of-the-pen, though, when he defined Va as 'minimum maneuvering speed'.

 

By the way, have you been able to install and check-out the AoA thingy you were looking at?

 

 

[Kyle Communications]

Have you installed your belite one yet?

 

 

[Garfly]

Yes, but I've been away OS most of this year and haven't had a chance to try it out.

 

The display has gone into a spare hole, mid-panel, for now, but it could go to a heads-up arrangement if needs be.

 

 

 

 

 

[Kyle Communications]

I think the display needs to be heads up or on the top of the dash. It really needs to be within your field of vision when landing I think