16 hours ago, ual763 said:

You're assuming the updrafts/downdrafts are always at a 90° angle to the wing chord with no horizontal component.  If there is any horizontal movement to said updraft/downdraft, (which 99.9% of the time there is), there will be fluctuations in airspeed and also coincidentally AoA.

 

Nope... not assuming anything. The premise was that AoA indicator is an accurate indication of vertical speed. It's not. 99.9% of the time always a change in apha with an updraft is a random percentage you came up with. It's perfectly feasible that an updraft or dowdraft could occur without impacting velocity.

Same in reverse. Your angle of attack indicator might change due to a change in velocity, so what do you do, believe its caused by an up or down draft when it wasnt?

Do you see how the original premise regarding the AoA indicator as an "accurate" substitute for the VSI is erroneous?

16 hours ago, FDEdev said:

Suggest to do a bit of basic research before posting. It's e.g. essential knowledge that stall speed increases with bank angle (stall AoA remains the same)

 

 

Huh... what's bank angle got to do with it. Bank angle decreases stall speed it does't increase it. And that's because the direction of lift is offset from the vertical.

 

This conversation is nothing to do with bank angle. The premise was that an AoA gauge can serve as an "accurate" substitute for a VSI. Which is wrong. What happens if your aircraft decelerates thus reducing Alpha and you mistake that for a chage in vertical speed. Makes no sense.

Edited March 4, 20206 yr by martin-w

16 hours ago, w6kd said:

 

If only the airspeed changes, say for example in a decreasing headwind wind shear scenario. the AoA does not change as a result of the suddenly reduced headwind.   Until a correction is made, the AoA remains the same at the reduced velocity

 

 

Nope. If air speed drops the flight path vector drops. Thus angle of attack increases. As the flight path vector is down, airspeed would then  increase and AoA reduces again.

Edited March 4, 20206 yr by martin-w

<plonk>

4 hours ago, domkle said:

Is it a panel gauge or a small HUD on the glare shield ? The HUD allows peripheral vision without having to lower your eyes, don’t you think ? 

I don't have any capability to add things to the interior model file. 

The first gauge was a 2D panel made using the FSX tutorials.  I've added the AoA to existing panels in other aircraft, and I'm currently using the Shift-Z text to display it.  I didn't use that text originally because it did not display the correct number.

A HUD would be nice but I don't fly aircraft modern enough to have something like that. 😄  The Icon gauge is fine with me.

Hook

11 minutes ago, LHookins said:

I don't have any capability to add things to the interior model file. 

The first gauge was a 2D panel made using the FSX tutorials.  I've added the AoA to existing panels in other aircraft, and I'm currently using the Shift-Z text to display it.  I didn't use that text originally because it did not display the correct number.

A HUD would be nice but I don't fly aircraft modern enough to have something like that. 😄  The Icon gauge is fine with me.

Hook

 

My request for a HUD, isnt so much about accurate simulation. More to do with a quality replacement for the dodgy instrument only view. 

14 minutes ago, LHookins said:

.

A HUD would be nice but I don't fly aircraft modern enough to have something like that. 😄  The Icon gauge is fine with me.

Hook

Look at the vid I spoke of. The guy flies a 182 and, sometimes, a T6. That reminds you of your favorite aircraft dev, doesn't it ? The Valkyrie is priced at 500 USD which not small change but still reasonable if you can afford a Skylane. It is not a full fledged HUD which would be in thousands, just for the AoA.

 

2 hours ago, martin-w said:

Bank angle decreases stall speed it does't increase it. And that's because the direction of lift is offset from the vertical.

1. It's funny to watch how you are digging your own hole deeper with every post. You even have an 'explanation' to support your flawed theory. 

Maybe this will help you understand at least the basics:

https://www.boldmethod.com/learn-to-fly/aerodynamics/why-does-aircraft-stall-speed-increase-with-bank-angle/

 

Edited March 4, 20206 yr by FDEdev

I think if you guys reframe the picture of what is moving, it might clear things up for everyone. Instead of thinking of the plane flying through the air, think of the air moving past the plane.

 

If you're flying straight and level at 100kts on a completely calm day, it's the same thing as the plane being completely still while a 100 knot wind flows from nose to tail.

If the wind changes such that there is an updraft or downdraft in addition to the 100kt horizontal component, then it is no longer a 100 knot wind flowing directly from nose to tail. The vector of the air's velocity has changed - it's either going up or down at an angle rather than straight at the plane.

As it hits the wing, the angle of attack *is* different, even if the plane doesn't climb or descend.

Remember that AOA involves the *relative* wind as measured against the chord of the wing, not the absolute wind.

 

martin-w stop it, there are multiple RL pilots saying you're wrong (and they're right indeed).

It is true, as you say, that the AoA is not an indicator of vertical speed. But nobody ever stated that. What was stated instead, is that an AoA indicator is a good indicator of bumps and sinks caused by updrafts and downdrafts. Updrafts and downdrafts do cause spikes in AoA, even if they're directly vertical, and even if the airspeed stays the same. This is not debatable, just do some research on your own, watch videos, etc.

You are confusing short term AoA spikes with long term AoA changes due to airspeed, change in flight controls, etc.

 

1 hour ago, Murmur said:

martin-w stop it, there are multiple RL pilots saying you're wrong (and they're right indeed).

It is true, as you say, that the AoA is not an indicator of vertical speed. But nobody ever stated that. What was stated instead, is that an AoA indicator is a good indicator of bumps and sinks caused by updrafts and downdrafts. Updrafts and downdrafts do cause spikes in AoA, even if they're directly vertical, and even if the airspeed stays the same. This is not debatable, just do some research on your own, watch videos, etc.

You are confusing short term AoA spikes with long term AoA changes due to airspeed, change in flight controls, etc.

This ^^^

It's that pesky delta-t that's getting in the way here.  We're talking about rapid (functionally instantaneous) disturbances of the air mass vector.  The effects on AoA Martin describes above do not occur instantaneously, they occur over time as the acft seeks a new equilibrium.  When an up/downdraft hits the acft, the observed/indicated change in AoA is as nearly instantaneous as the onset of the draft itself...the acft will then change its flight path relatively slowly until equilibrium is achieved.  You can definitely see it in an acft...e.g. landing on rwy 24L/R at Anderson AFB in Guam, which brings you in over a 600' oceanside cliff.  The practically omnipresent updraft above that sheer face will give a noticeable bump to the AoA as you pass across it.

 

 

5 hours ago, FDEdev said:

 

1. It's funny to watch how you are digging your own hole deeper with every post. You even have an 'explanation' to support your flawed theory. 

Maybe this will help you understand at least the basics:

https://www.boldmethod.com/learn-to-fly/aerodynamics/why-does-aircraft-stall-speed-increase-with-bank-angle/

 

 

Firstly, please stop being rude. It's not necessary.

Now please explain how a change in stall speed while banking is relevent to the premise that an angle of attack indicator is an "accurate" substitute for a vertical speed indicator? It's not.

 

2 hours ago, Murmur said:

martin-w stop it, 

 

 

Why is it necessary for rudeness to creep in just because someone disagrees with others. It's not necessary. Let's be adult and friendly shall we. I will continue to disagree and provide counter points if I do actually disagree. Unless of course you convince me. But please do so politely.

Edited March 4, 20206 yr by martin-w

9 minutes ago, martin-w said:

I will continue to disagree and rovide counter points if I do actually disagree. Unless of course you convince me. But please do so politely.

It's very difficult to stay polite if you are so stubborn and continue your completely wrong claims over and over again. You are disregarding everything w6kd, Murmur and I explained to you. 
What do you expect? You are even disregarding the basic info in the link I provided. 

How should anyone be able to 'convince' you and why should anyone try to continue doing so? 

15 minutes ago, martin-w said:

Now please explain how a change in stall speed while banking is relevent to the premise that an angle of attack indicator is an "accurate" substitute for a vertical speed indicator? It's not.

Murmur already wrote:  It is true, as you say, that the AoA is not an indicator of vertical speed. But nobody ever stated that.

Btw, I'm out.

Edited March 4, 20206 yr by FDEdev

2 hours ago, Murmur said:

 

It is true, as you say, that the AoA is not an indicator of vertical speed. But nobody ever stated that. What was stated instead, is that an AoA indicator is a good indicator of bumps and sinks caused by updrafts and downdrafts. Updrafts and downdrafts do cause spikes in AoA, even if they're directly vertical, and even if the airspeed stays the same. This is not debatable, just do some research on your own, watch videos, etc.

 

 

 

Okay, so then please explain to me how a vertical updraft, with no change in aircrafts airspeed thus no change in angle of attack, can cause an instrument desighned to measure angle of attack to fluctuate? And if it does fluctuate, how would you know that was caused by an updraft or downdraft rather than a change in airspeed.

Given the above, I maintain that using the AoA indicator as, what was described previously, as "acurate" feedback for updrafts and down drafts is in error.