Angle of Attack
? Sorry I don't get your rolling of the eyes..
The text I quote from you was your response to a comment upon stick position.
So you are saying in a Yak 52 you have full backstick during an orbit??
The text I quote from you was your response to a comment upon stick position.
So you are saying in a Yak 52 you have full backstick during an orbit??
One thing which everyone seems to be missing is that practically all small aircraft (excluding types designed primarily for aerobatics) do have an AoA indicator. It's pretty binary in nature - "too much Pitch" vs "you're OK". It's called the stall warning horn. There's no reason I can think of, other than the last second of a landing, why you should be flying in the "not OK" region, i.e. with the stall horn sounding. (There are flight training reasons but you're deliberately flying close to the edge of a stall).
So for non-aerobatic purposes, you have a perfectly fine AoA indicator. If the stall horns sounds, push. If you're making normal flight regime gentle inputs, there's plenty of margin between the warning (about 10-20% above the current stall speed generally) to relax the pull before anything bad happens.
Aerobatics are a different case. I agree with whoever said that if your head is inside the cockpit looking at gauges while you're doing something tricky, you're already in deep do-do. You just have to have the feel of the aircraft. At altitude, if it snaps, well you'll know where it happened for next time. At low altitude... you'd better know the aircraft well enough that it doesn't happen.
So for non-aerobatic purposes, you have a perfectly fine AoA indicator. If the stall horns sounds, push. If you're making normal flight regime gentle inputs, there's plenty of margin between the warning (about 10-20% above the current stall speed generally) to relax the pull before anything bad happens.
Aerobatics are a different case. I agree with whoever said that if your head is inside the cockpit looking at gauges while you're doing something tricky, you're already in deep do-do. You just have to have the feel of the aircraft. At altitude, if it snaps, well you'll know where it happened for next time. At low altitude... you'd better know the aircraft well enough that it doesn't happen.
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I agree with whoever said that if your head is inside the cockpit looking at gauges while you're doing something tricky, you're already in deep do-do. You just have to have the feel of the aircraft. At altitude, if it snaps, well you'll know where it happened for next time. At low altitude... you'd better know the aircraft well enough that it doesn't happen.
The Mil fly AoA. So does the aeroplane. EVERY aeroplane.
Me? I'm with the Mil. And with the aeroplane.
Last edited by Shaggy Sheep Driver; 8th Jan 2016 at 22:54.
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There seems to be a few who are confusing an AoA indicator with a stall warner. They are not the same thing!
The stall warner warns at a point very close to the actual stall, no information is given prior to that. The AoA READS the AoA all the way from zero to beyond the stall. A stall warner is like having a buzzer that only sounds two knots below VNE instead of an ASI.
In Cessnas I have frequently landed with the horn sounding, my a/c doesn't have one and I've made 40deg banked turns on final for 9 years in it with no problems (nose down of course). I would love to know exactly how close I am to sudden death!
As for flying the "bum" how does one calibrate the bum between a gentle squeeze and something you may get in an Essex bus shelter?
The stall warner warns at a point very close to the actual stall, no information is given prior to that. The AoA READS the AoA all the way from zero to beyond the stall. A stall warner is like having a buzzer that only sounds two knots below VNE instead of an ASI.
In Cessnas I have frequently landed with the horn sounding, my a/c doesn't have one and I've made 40deg banked turns on final for 9 years in it with no problems (nose down of course). I would love to know exactly how close I am to sudden death!
As for flying the "bum" how does one calibrate the bum between a gentle squeeze and something you may get in an Essex bus shelter?
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? Sorry I don't get your rolling of the eyes..
The text I quote from you was your response to a comment upon stick position.
So you are saying in a Yak 52 you have full backstick during an orbit??
The text I quote from you was your response to a comment upon stick position.
So you are saying in a Yak 52 you have full backstick during an orbit??
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SSD attempted a defence of a poor argument with;
It still needs work. You are still lacking a coherent argument, even after allowing for poor grammar. You can (must) do better. Stop digging and stop being rude.
SSD also stated:
So, why do your favorite 'chippy' (De Havilland Chipmunk, I presume, colloquial name) or the Bulldog T.Mk1, the mainstays for decades of primary/elementary training (can't vouch for the successors) not have an AoA indicator?
Could it be that' the Mil' ( again, I'll presume you mean The Military) teach AoA via ALL the other indicators including 'seat of your pants', did 'the Mil' teach you AoA? Are the Mil with YOU?
AOA is of course the engineers' term translated to the user ie pilot as... various different speeds (wait for it..) in different configurations/attitudes/power settings and other variables which may or may not be taught/required knowledge at different licence/rating levels.
And yes, the aircraft (or any other object not tied to the ground or in contact with it) knows it intimately without ANY training.
AOA indicators could be a fantastic 'thing' if only we knew how to make them cheap/understandable by all/necessary/mandatory, not necessarily in that order.
There are much better qualified people than me who have used them (see posts above) and the impression I get is that it is another instrument to be glanced at and ready to fail when relied upon, in isolation.
But we use lots of instruments that can and do fail so is AOA a concept not readily graspable by the many (and thus more relevant to the 'pushing the envelope for a living/hobby brigade') requiring advanced training?
Could we save considerably more lives merely by putting them in or spend much more money unnecessarily. The fact that we are without them suggests the latter.
Coat, Hat etc.
JJOE
Do I take it English is not your first language? If so, I apologise. One pulls to the limit... of AoA on the gauge, or 'G' if that is the limit you reach before the AoA limit. It will always be a lot less than full back stick!
SSD also stated:
The Mil fly AoA. So does the aeroplane. EVERY aeroplane.
Me? I'm with the Mil. And with the aeroplane.
Me? I'm with the Mil. And with the aeroplane.
Could it be that' the Mil' ( again, I'll presume you mean The Military) teach AoA via ALL the other indicators including 'seat of your pants', did 'the Mil' teach you AoA? Are the Mil with YOU?
AOA is of course the engineers' term translated to the user ie pilot as... various different speeds (wait for it..) in different configurations/attitudes/power settings and other variables which may or may not be taught/required knowledge at different licence/rating levels.
And yes, the aircraft (or any other object not tied to the ground or in contact with it) knows it intimately without ANY training.
AOA indicators could be a fantastic 'thing' if only we knew how to make them cheap/understandable by all/necessary/mandatory, not necessarily in that order.
There are much better qualified people than me who have used them (see posts above) and the impression I get is that it is another instrument to be glanced at and ready to fail when relied upon, in isolation.
But we use lots of instruments that can and do fail so is AOA a concept not readily graspable by the many (and thus more relevant to the 'pushing the envelope for a living/hobby brigade') requiring advanced training?
Could we save considerably more lives merely by putting them in or spend much more money unnecessarily. The fact that we are without them suggests the latter.
Coat, Hat etc.
JJOE
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Just to speak to a critical point: on an aircraft without leading edge devices, there is no point to configuration changes being fed to the AOA indicator. This is exactly where the whole business of knowing AOA vs. IAS comes into play. The wing will stall at pretty much the same AOA regardless of configuration (I say about because there MIGHT be some small changes in airflow due to configuration - mostly related to prop wash, minor in singles, significant in twins and of course MASSIVE in some multis - ask a L188 driver what I mean. The AOA indicator is trying to tell you where you are relative to the actual AOA from which all wing performance is derived. Stall is only one, and it is the point at which flow separates rapidly over the top surface - not at all dependent upon things such as flap position or aircraft weight - all of which means a mess of calculations to try to get the same information from IAS.
Going back to the other sub-plot of the topic: If the AF447 guys had been taught to fly by an AOA - and taught WHY and HOW it related to lift, there is a very good chance they could have been aware of just what information of all that was on their panel was most critical - or in this case, what was NOT on their display - AOA. While most instrumentation and avionics put distance between pilotage and pilot, there is a likelihood that use of AOA could bring them together.
Many, many years ago, I was spoiled by spending some time with some jet jocks. There was no HUD in those days, and to be a fighter pilot, you had to keep your eyeballs and cranium on a constant swivel - to stay alive. NO WAY you were going to be looking at an ASI or even an AOA indicator to fly the airplane to its maximum performance. They taught me to fly in an airplane with very little excess of thrust but 100% head out of cockpit. I don't recommend trying to manage a light twin with one fan in the process of being caged that way, mostly because I kind of do that by the book due to lack of familiarity (my only multi I flew only on maintenance and training trips). But on singles - including some with pretty rude stall and spin behaviour - I can pretty much take a wing to its limit and have it at any one of three stages before a full stall with complete confidence. I could do the same thing AND find the best rate, angle, etc. sweet spots with an AOA WITHOUT all of that pretty disciplined training and do so in a completely unfamiliar airplane.
Win, Win on the safety front (and performance as well).
Going back to the other sub-plot of the topic: If the AF447 guys had been taught to fly by an AOA - and taught WHY and HOW it related to lift, there is a very good chance they could have been aware of just what information of all that was on their panel was most critical - or in this case, what was NOT on their display - AOA. While most instrumentation and avionics put distance between pilotage and pilot, there is a likelihood that use of AOA could bring them together.
Many, many years ago, I was spoiled by spending some time with some jet jocks. There was no HUD in those days, and to be a fighter pilot, you had to keep your eyeballs and cranium on a constant swivel - to stay alive. NO WAY you were going to be looking at an ASI or even an AOA indicator to fly the airplane to its maximum performance. They taught me to fly in an airplane with very little excess of thrust but 100% head out of cockpit. I don't recommend trying to manage a light twin with one fan in the process of being caged that way, mostly because I kind of do that by the book due to lack of familiarity (my only multi I flew only on maintenance and training trips). But on singles - including some with pretty rude stall and spin behaviour - I can pretty much take a wing to its limit and have it at any one of three stages before a full stall with complete confidence. I could do the same thing AND find the best rate, angle, etc. sweet spots with an AOA WITHOUT all of that pretty disciplined training and do so in a completely unfamiliar airplane.
Win, Win on the safety front (and performance as well).
my a/c doesn't have one and I've made 40deg banked turns on final for 9 years in it with no problems (nose down of course). I would love to know exactly how close I am to sudden death!
1. Take the published stall speed (in the same condition wrt flaps, gear etc) and multiply by 1.09 = 1/(sqrt(tan(40 degrees))).
2. Take the above figure as a guide, add 5 knots, and fly the maneouvre at altitude. Reduce speed by 1 knot at a time and repeat until you stall.
Though stalls don't happen all at once. Unless you're flying an aerobatic hotshot (like the Yak-52/54) the inner wing stalls before the outer wing. So the notion of a single stall speed is kind of a convenient fiction. But it's close enough.
Of course a stall isn't sudden death. Unless you're REALLY low (below 200 feet), just break the stall and recover. Unless you're flying a type that tends to snap (e.g. the Marchetti 260), in which case replace REALLY low with just low (below 1000 feet).
The Chipmunk and Bulldog in military service were both equipped with wing root leading edge 'toblerones' (triangular strips) which induced buffet over the tailplane and elevators as AoA increased - pulling to the 'buffet nibble' would mean that you were at the max turning performance. The toblerones gave excellent natural AoA perception.
The last Bulldog I flew had unfortunately been fitted with a stall warning horn, presumably as part of its civilianisation conversion. It was as useless as most others of the type (e.g. as fitted to the PA28) and would sound well before the stalling AoA was reached - it ruined the aircraft for any spirited flying.
The last Bulldog I flew had unfortunately been fitted with a stall warning horn, presumably as part of its civilianisation conversion. It was as useless as most others of the type (e.g. as fitted to the PA28) and would sound well before the stalling AoA was reached - it ruined the aircraft for any spirited flying.
It was as useless as most others of the type (e.g. as fitted to the PA28) and would sound well before the stalling AoA was reached
Beags
I might be mistaken but think I can vaguely recall that our Bulldogs had the stall warning horn fitted when our UAS converted to them in 77/78.
The last Bulldog I flew had unfortunately been fitted with a stall warning horn, presumably as part of its civilianisation conversion.
When I flew the Bulldog on the UAS in the late 80s, then ran some flight testing on them at BDN in the mid 90s, the stall warning vane was fitted, but disabled as the RAF concluded it was of negative training value.
G
G
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JJOE I read your post 3 times, but I couldn't understand it. Could you try again, please? In grammatical, well constructed, English? In particular was it me or Pittsextra you were attempting to poke in the eye?
Sheep driver. I'm not sure why me asking you to clarify a point suddenly makes me less able to understand English. Language barrier to one side - I just wasn't really clear on the point you made when you wrote:-
which you later clarify as:-
Thank you for that insight. I would like to ask another question, if you might be so kind as to educate me, as to the process when performing other manoeuvres? To further clarify, because I struggle with this damn English, does your latter comment only apply to these "max performance 360" ??
I've spent a lot of time running this through spell and grammar checker and wot I rote shud b gud.
Shaggy Sheep Driver said:-
In a sustained pull (max performance 360 for instance) one can pull to the limit!
In a sustained pull (max performance 360 for instance) one can pull to the limit!
One pulls to the limit... of AoA on the gauge, or 'G' if that is the limit you reach before the AoA limit. It will always be a lot less than full back stick!
I've spent a lot of time running this through spell and grammar checker and wot I rote shud b gud.
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The last Bulldog I flew had unfortunately been fitted with a stall warning horn, presumably as part of its civilianisation conversion. It was as useless as most others of the type (e.g. as fitted to the PA28) and would sound well before the stalling AoA was reached - it ruined the aircraft for any spirited flying.
I have enjoyed spirited flying in aircraft with functioning stall warning systems (and without). The operation of a stall warning system does not prevent the spirited flying, it just presents additional information in some phases.
The few military types I have flown which did not have stall warning systems at all were also perfectly fine to fly, though I can imagine a low time, quasi trained pilot being at higher risk of departing controlled flight. Like AoA systems now coming to the forefront, decades ago when stall warning systems (as opposed to aerodynamic warnings), I think the piloting skills began to dumb down in respect of stall awareness - "I don't care, the stall warning will let me know". On the other hand, I believe that military pilots are much better trained from the beginning, so stall awareness is ingrained early, and becomes muscle memory. Civil pilots can certainly get there too, with devotion. The problem is that the civil industry seems to do whatever it can to suppress or devalue devotion to learning hands and feet skills - and the AoA system, and stall/spin resistance of the Icon A5 don't help that situation....
