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Idea for portable AOA device


jaylw314

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41 minutes ago, 201er said:

How is keeping two balls centered in the pattern math???

Did you look at what I said earlier and the wiki link to observability-controllability?

You are observing a measurement and trying to control a dynamic process based on indirect measurements of I nferred measurements of state  That is the duality problem of observability and controllability.  At the heart of control theory.  You are doing math wether you know it or not as surely as you are doing math when you toss a ball in the air and catch it after a parabolic arc whether you understand that or not.

Edited by aviatoreb
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Note... not a CFI writing this post...  Just a PP learning as I go...

 

Math and memory are all that's required... Lose one, and the other works overtime!

 

Pilot's bird brain... near or in the traffic pattern... may calculate... (birds seem to do this all the time without discussing the math behind it)

1) power setting to decelerate (negative acceleration) to traffic pattern speed.

2) Amount Of time to Required to be on speed, abeam the numbers...

3) power setting to begin the descent...

4) adjustment of power setting to acquire the desired rate of descent.

5) bank angle and adjustment to acquire the desired rate of turn.

6) rate of adjusting the bank angle to not generate any snap rolls...

7) rate of adding and removing any control inputs.... important when crossed controlled inputs are being used...

That's just the ordinary math going on...

8) how much more rudder is needed to keep the ball centered, right now?

9) How much pedal pressure is going to be needed to keep the ball centered?

10) Will I have enough strength left... to keep this control force in, til landing? (One of our MS pro writers had this stuck trim Math challenge... She did extremely well with the math, and the strength. :))

 

The same bird brain on final approach, has all the variables set for the landing condition... all he needs are...

  • final approach speed for the weight the plane is carrying.
  • a buffer for gusts.
  • a buffer for human error.
  • a source of information regarding weight and approach speeds. (Memorized or looked up)
  • a final bit of nice to have info... stall speed in ground effect for the plane with the finished loading data....

 

To get to final approach without being too high and too fast, a lot of energy needs to be dissipated.  The rate of dissipation changes immensely with changes of configuration...

  • Gear down
  • prop in
  • flaps 1/2, flaps down
  • Steep or shallow turns
  • Slips
  • speed brakes deployed

 

Spins need a stall to occur first. Avoiding a stall is pretty good at avoiding a spin...

To avoid a stall... the old fashioned way...

  • Keep speed above the charted stall speed for the bank angle and flap setting being used.
  • Using too large of a speed buffer becomes a challenge to getting slowed later.
  • Using shallow banks keeps the speed/bank angle in control.
  • Ball centered is required when using charted stall speeds.
  • Keep the nose at or below the horizon. Above the horizon can put you behind the power curve, slowing quickly... and is a poor AOA for nearing a stall condition...
  • lowering the nose, unweights the wings (changes the AOA), acts like a speed buffer...
  • If using a slip, the nose is kept down significantly for a reason.

 

Memory test... do you have a set of targe speeds memorized for... similar to these? (Plane specific and pilot specific)

  • Down wind. 90?
  • Base. 80?
  • Final. 75 - 65? Weight of flight dependent, and a buffer for wind conditions...

 

Memory test two... do you have sets of stall speeds memorized for 

  • Max and minimum weight...
  • Bank angles of 30° at max and minimum weight...
  • turn to base with flaps 1/2.
  • turn to final with flaps full.

 

Avoiding a stall is critical in the traffic pattern. There is precious little space for recovery... nevermind having a spin develop.

 

In lieu of having all the stall speeds memorized and used in the proper order... It is possible to use an AOAi.

You wouldn't even need to do the math of calculating the final landing weight.

 

Fortunately for us... the human brain is no bird brain...

 

Lots of math and memory involved... often without recognizing the effort used... :)

Briefly, in one line...  an AOAi can supplement a whole bunch of memory and math skills in the traffic pattern....

PP thoughts only, not a CFI...

 

Best regards,

-a-

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On 2/2/2018 at 12:19 PM, DXB said:

It's striking to me that Aspen offers a perfectly good AoA indicator based on integration of AHRS and airspeed data, with no additional external sensor.  What has kept me from adopting so far is the itty bitty display for it on my pfd.  An external display for the glare shield using the same data (via the Aspen or otherwise) would make me buy in an instant.  I am not fond of the idea of another install out on my wing when the needed data is already in the cockpit.  

I have the Aspen AOA... it was on sale at 50% off a couple of months ago. I find the display plenty large and easy to see right in my field of vision when landing.

I only use it when I'm trying to come in as slow as I safely can. Otherwise, I'm usually plenty fast. I don't subscribe to the theory that landing fast is catastrophic for a Mooney. So I usually land fast... but I also usually have plenty of runway. On the days I need to practice for short landings or in the unlikely event I have to dead stick it into a field somewhere, I use my AOA and try to make the first taxiway at 700'. It used to be easy in the C, in the K it's a bit more sporty.

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9 hours ago, 201er said:

What are you rambling about? All you need to do is keep the ball centered on the slip indicator with the rudder and the indication centered “on the ball” on the aoa indicator with pitch. There’s no math. There’s no pitot tubes on both sides. Just keep the two indications centered or as close to centered as possible on approach and you will not stall (including very steep turns in the pattern).

I only sometimes look at the gauges while landing so don't get grumpy with me.  My day job is keeping small towns across the US from getting blown off the map.  @Aviatoreb knows what I am talking about.   In Control Room Management you will change screen colors to direct the attention of the Controller to where he should be looking.

Since you have nothing useful to add to the conversation, you are now invited to leave.

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6 hours ago, carusoam said:

Memory test... do you have a set of targe speeds memorized for... similar to these? (Plane specific and pilot specific)

  • Down wind. 90?
  • Base. 80?
  • Final. 75 - 65? Weight of flight dependent, and a buffer for wind conditions...

Memory test two... do you have sets of stall speeds memorized for 

  • Max and minimum weight...
  • Bank angles of 30° at max and minimum weight...
  • turn to base with flaps 1/2.
  • turn to final with flaps full.

 

 

See I knew this would go the way of a landing discussion

 

 

 

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On 2/4/2018 at 1:38 PM, Yetti said:

OK so how does the AoAi take into account the current weight of the airplane, or is it just a estimated safe envelope?

 

Yetti,

You asked a great tough question..

I outlined how long the answer can be. From a PP point of view.

included the challenges some people have.  

  • Some people have great memories and have the charts easily in their heads.
  • Some people can scan and multi-task at a higher level.
  • if a pilot has these skills, he can better skip the AOAi.
  • I have reached a point where memory isn't a very strong point.

I think you may taken my points as an attack on your memory.  My oppologies for any offense.

 

I was more looking for feedback on my understanding of the systems and situation.  I Probably should have focused a little harder on how I was saying it than what I was saying.

I have come a long way from the two or three line lists.  Just not there yet.   :)

Best regards,

-a-

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So three pages in and we still don't have a good problem definition.   Or we have a solution AoAi in search of a problem.   I am failing as a Business Analyst.

My suggestion for problem definition is that we are trying to solve LOC fatalities in the pattern area during approach and landing.   Lots of people suggest that an AoAi can do this.   Some people say that the current instrumentation can do the same people just don't know what to do with what the instruments are telling them.  Some people say that you need to calculate a landing speed for each landing.  One university says a U turn to land will help prevent fatalities.

Oh look here are some statistics to help us understand what we are trying to solve for.

https://www.ntsb.gov/investigations/data/Pages/AviationDataStats.aspx#

I believe Cirrus have an AoAi and it was not helpful the pilot landing at Hobby

 

 

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Jay the OP was discussing the possibilities of a portable AOAi...

Kind of an open ended statement leading to questions...

A bunch of quick design challenges were brought forth...

Discussion included different types of sensors that could help the project...

while waiting for next steps... a discussion of the values of the AOAi ensued...

A couple of younger MSers, with great memory skills, have given examples of how they use their AOAis...

The long discussion continues...

  • Most agree that an AOAi can benefit the entire pilot population
  • Cost can be a challenge.
  • Building a portable at the right price would be appreciated by some.
  • building a usable portable, at the right price is going to take a lot of effort.
  • Piloto indicated a simple system that may actually work. Unfortunately it is hard to look out the side window while landing that day...

We probably all agree, if a pilot doesn't use the data, no matter how pleasantly it is displayed, it won't help...

The Cirrus at Hobby was a pretty task saturated event. An AOAi, the phrase unable, And/or a red pull handle couldn't make a difference.

 

Ask @jaylw314 If there is an update?

 

I believe he was only sharing an idea he had earlier in the day....  Spawning a conversation of MSers... nothing more.

As he said....

“Anyway, just my brain droppings for today...”

 

Is there any interest in a portable AOAi?  Seems like there could be...

 

Best regards,

-a-

 

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"The Cirrus at Hobby was a pretty task saturated event. An AOAi, the phrase unable, And/or a red pull handle couldn't make a difference. "

I still believe to the pilot the ATC person took on the role of CFI and she started following the voices in her headset like you do when learning to fly.   The ATC person said "tighten up the turn"  so she complied just like with a CFI.

What I am suggesting with a better than flashing light AoA is have that voice in your head tell you either what you are doing wrong or what you need to do to not crash.

The AoAi is just a LED way to simplify the ASI and some rules about airspeed low to the ground.

Yes we could recreate an Low cost LED portable way of flying the plane, but will it keep people from crashing their plane?  The university study said that if the engine is out then yes AoAi adds value to the cockpit.    Otherwise they are just a way to slow down a bit on landing.

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8 hours ago, Yetti said:

So three pages in and we still don't have a good problem definition.  

Oh, it's been much, much longer than that.

Dont forget, we had this exact same conversation about 2 years ago, even to include Stinkypants commenting how the rest of us were "old"!

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