Evaluating stall characteristics - best procedure?
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Evaluating stall characteristics - best procedure?
I recently had the interesting experience of sitting in on a preliminary evaluation of a light aircraft (DA42) by a French military test pilot at CEV Istres. One of the checks was on the stall characteristics.
I was interested to observe that the TP seemed to pay no attention to holding the altitude steady in the approach to the stall, and the stall characteristics (both clean and in landing configuration) were recorded when we were in a descent of around 700fpm. He appeared to keep the stick deflection constant as the stall approached.
This seemed odd to me (as just a CPL) as in all the training I have ever been subjected to, I have been told to maintain altitude until stall, requiring a rapidly increasing stick deflection as we go down the wrong side of the lift/drag curve.
As a frustrated wannabee test pilot I'd be grateful for any comments!
I was interested to observe that the TP seemed to pay no attention to holding the altitude steady in the approach to the stall, and the stall characteristics (both clean and in landing configuration) were recorded when we were in a descent of around 700fpm. He appeared to keep the stick deflection constant as the stall approached.
This seemed odd to me (as just a CPL) as in all the training I have ever been subjected to, I have been told to maintain altitude until stall, requiring a rapidly increasing stick deflection as we go down the wrong side of the lift/drag curve.
As a frustrated wannabee test pilot I'd be grateful for any comments!
CirrusF, the difference is that the emphasis on maintaining height /minimising height loss at/beyond the stall is a training requirement,not an `absolute numbers` requirement as in stall testing.
For stall-testing it is necessary to stall the aircraft in a configuration(clean/gear flaps etc) as close to 1g as is possible,with in most,but not all configurations,zero thrust/torque(props)/idle thrust(jet) as is possible,and this will mean in a shallow descent.
The approach to the stall is usually started at about 1.3-5 Vs depending on type/configuration,and then the a/c is slowed down at a rate of speed reduction of between 1-2 kts/sec. whilst noting all the effects,ie buffet onset,aileron `*******`/snatch,yaw,nose slicing,pitch-up,buffet,control activity/position/forces,etc,etc,same with ASI/Vibrations ,etc. Then one looks at the stall `break`,clean,nose dropping,wing-drop,yaw,or is it a `pussy-cat`? Then you go and do it all again to be repetitive/consistent,then at all CofG positions,fuel loads ,etc.
That`s a rough-guide;it also should be noted that the instrumentation in the aircraft should have been calibrated if /wherever possible,otherwise one can be wasting a lot of effort.
Hope that helps..Syc..
For stall-testing it is necessary to stall the aircraft in a configuration(clean/gear flaps etc) as close to 1g as is possible,with in most,but not all configurations,zero thrust/torque(props)/idle thrust(jet) as is possible,and this will mean in a shallow descent.
The approach to the stall is usually started at about 1.3-5 Vs depending on type/configuration,and then the a/c is slowed down at a rate of speed reduction of between 1-2 kts/sec. whilst noting all the effects,ie buffet onset,aileron `*******`/snatch,yaw,nose slicing,pitch-up,buffet,control activity/position/forces,etc,etc,same with ASI/Vibrations ,etc. Then one looks at the stall `break`,clean,nose dropping,wing-drop,yaw,or is it a `pussy-cat`? Then you go and do it all again to be repetitive/consistent,then at all CofG positions,fuel loads ,etc.
That`s a rough-guide;it also should be noted that the instrumentation in the aircraft should have been calibrated if /wherever possible,otherwise one can be wasting a lot of effort.
Hope that helps..Syc..
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Speaking as a retired instructor and CPL, remembering my own experiences...
Are cross-controlled stalls normally investigated during flight test? When I had 50 hrs or so I was checking out with an instructor in an old Ryan PT-22 WWII trainer. He had plenty of experience in the type, and asked me to try a power-off stall with a bit of slip. The result - a very rapid snaproll (flick if you like) 1 or 2 knots above Vs. No warning at all. At low altitude it could be deadly.
Other than that, the PT-22 was a very likable ship.
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(Post edited by moderator because of over-large photograph - you can still look at it by clicking the link above.)
Are cross-controlled stalls normally investigated during flight test? When I had 50 hrs or so I was checking out with an instructor in an old Ryan PT-22 WWII trainer. He had plenty of experience in the type, and asked me to try a power-off stall with a bit of slip. The result - a very rapid snaproll (flick if you like) 1 or 2 knots above Vs. No warning at all. At low altitude it could be deadly.
Other than that, the PT-22 was a very likable ship.
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(Post edited by moderator because of over-large photograph - you can still look at it by clicking the link above.)
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You would think if the bloke in the front cockpit couldn't afford a crash helmet he could at least wear one of those elongated perforated head gear used by cyclists. Might even get a couple of more knots because of reduced drag
Back to Cirrus' original post.
There seems to me to be a definite mismatch between...
TP: "1kn/s decel, as close to 1g as possible, identify the stall and stall warning characteristics and document them"
Instructor: "minimise height loss, whatever decel rate goes with that, stall warning is audible or very clear buffet - nothing else counts, stall is marked by a pitch break, if you don't get one, pull back harder on the stick".
In the military flight testing world, there's a concept called "role relation" - where test methods and evaluation are modified to match the way the aeroplane will be operated in service. UK CAA has always insisted that it's light aircraft Test Pilots are also FIs of some description, giving them the ability to role-relate, in the same way that a military TP who was recently a fighter pilot can reasonably assess a new fighter aircraft.
However, in my experience, a large proportion of TPs assessing light aeroplanes likely to be used for civil instruction are not FIs. This is arguably a deficiency, and perhaps is at the root of Cirrus' observations? Whilst the 1kn/s certification stall is certainly still needed for various reasons - such as the determination of Va, you could make a strong case that stalls similar to those in the PPL and CPL skills tests should also be flown as an exercise in role-relation.
Of course, most (all?) civil licenced TPs have at-least taken these tests, if not taught for them, which should give that understanding. But perhaps the military TP who Cirrus was flying with had not?
Ref: Barit's post - perhaps this is a role-relation issue also? In most aeroplanes, a snap role would not be a normal manoeuvre, and probably not even a reasonably expected bit of mishandling. In an aerobatic aircraft however, it would be, and I'd certainly hope to see it assessed. That test plan determination surely comes down to the knowledge of the test team, and in particular the test pilot(s) to get right?
G
There seems to me to be a definite mismatch between...
TP: "1kn/s decel, as close to 1g as possible, identify the stall and stall warning characteristics and document them"
Instructor: "minimise height loss, whatever decel rate goes with that, stall warning is audible or very clear buffet - nothing else counts, stall is marked by a pitch break, if you don't get one, pull back harder on the stick".
In the military flight testing world, there's a concept called "role relation" - where test methods and evaluation are modified to match the way the aeroplane will be operated in service. UK CAA has always insisted that it's light aircraft Test Pilots are also FIs of some description, giving them the ability to role-relate, in the same way that a military TP who was recently a fighter pilot can reasonably assess a new fighter aircraft.
However, in my experience, a large proportion of TPs assessing light aeroplanes likely to be used for civil instruction are not FIs. This is arguably a deficiency, and perhaps is at the root of Cirrus' observations? Whilst the 1kn/s certification stall is certainly still needed for various reasons - such as the determination of Va, you could make a strong case that stalls similar to those in the PPL and CPL skills tests should also be flown as an exercise in role-relation.
Of course, most (all?) civil licenced TPs have at-least taken these tests, if not taught for them, which should give that understanding. But perhaps the military TP who Cirrus was flying with had not?
Ref: Barit's post - perhaps this is a role-relation issue also? In most aeroplanes, a snap role would not be a normal manoeuvre, and probably not even a reasonably expected bit of mishandling. In an aerobatic aircraft however, it would be, and I'd certainly hope to see it assessed. That test plan determination surely comes down to the knowledge of the test team, and in particular the test pilot(s) to get right?
G
Do a Hover - it avoids G
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Whoa chaps.
I think some of us are confusing two very different topics here.
A. Getting useful and repeatable data regarding the stalling characteristics of an aircraft that is under test. This data will be needed for certification (whether the aircraft is mil or civ). Indeed many aspects of the service operation of the aircraft will be determined from this data such as the certificated approach speed which will be 1.3 times one (just one) of the very many different types of stall that will be tested.
B. Teaching students (mil or civ) to recognise a stall and how to deal with it confidently and safely then during later stalling exercises doing everything as efficiently as possible (this last word requires minimisation of height loss).
Good accurate and repeatable flight test data (on any topic not just stalling) requires that all parameters are as nearly constant (steady) as possible. In the case of basic stall data we want the angle of attack that is reported against some other parameter like g, bank angle, buffet onset, wing drop, nose drop etc to be as constant (steady) as possible.
Big point: the only things that affect the way the air flows round any aircraft that is well subsonic (in whatever configuration it happens to be in) are the angle of attack and angle of sideslip.
So to get data for case A above we need both AoA and sideslip angle to be as steady as possible. Eg With zero sideslip the AoA was 12 at buffet onset, 13.5 at first lateral stick snatch, 15 when the nose dropped or 16 when the stick reached fully back (or whatever all the numbers/events are as the ones I have quoted above are of no significance whatsoever)
If you allow me to bang on a bit longer about flight test techniques I hope it will become clear why I later say what I do about topic B.
A comprehensive stalling flight test programme requires a huge number of different stalls to be flown. There will be one set for each configuration typically TE flap angle LE device setting (if fitted as they say in the car handbooks) undercarriage position and most importantly they will all have to be looked at under different power settings to say nothing of CG, weight and altitude. If your aircraft can exceed about Mach 0.5 then throw in a whole lot more at different mach numbers.
But that is FAR from the end of the flight test stall programme. Once that is done there will be many more stall entries to be done with a rapid onset of angle of attack (now we are starting to get to the case B above)
Here the tp wants to establish what will happen in the unsteady case and is covering the flying club type of training stall or if you like the way a pilot might accidently blunder into an inadvertent stall. Necessarily if you close the throttle in level flight and then hold your height your airspeed will reduce quite quickly and very importantly your angle of attack will increase ever more quickly. Indeed this approach will likely produce quite a big AoA overshoot once the stall happens and before the student starts the recovery. The IAS will likely get to a silly low value and whatever reading it gets down to is likely to be pretty meaningless due to unknown pressure errors in these transient conditions.
So if you speak to a tp and he mutters about œ to 1 kt/sec and also says he ignores the flight path (which does not affect the airflow round the wing) he is talking about how he gets this nearly steady data and is not describing the stalling programme just one aspect of it.
Finally any flight test programme fully takes into account the role for which the aircraft will be used. So Cirrus there is no mismatch between what you were taught and what goes on in flight test. Happier?
I could also go on about how you keep stalling flight tests safe (they are by definition being done for the first time) but this post is too long already and there are books on all this.
I think some of us are confusing two very different topics here.
A. Getting useful and repeatable data regarding the stalling characteristics of an aircraft that is under test. This data will be needed for certification (whether the aircraft is mil or civ). Indeed many aspects of the service operation of the aircraft will be determined from this data such as the certificated approach speed which will be 1.3 times one (just one) of the very many different types of stall that will be tested.
B. Teaching students (mil or civ) to recognise a stall and how to deal with it confidently and safely then during later stalling exercises doing everything as efficiently as possible (this last word requires minimisation of height loss).
Good accurate and repeatable flight test data (on any topic not just stalling) requires that all parameters are as nearly constant (steady) as possible. In the case of basic stall data we want the angle of attack that is reported against some other parameter like g, bank angle, buffet onset, wing drop, nose drop etc to be as constant (steady) as possible.
Big point: the only things that affect the way the air flows round any aircraft that is well subsonic (in whatever configuration it happens to be in) are the angle of attack and angle of sideslip.
So to get data for case A above we need both AoA and sideslip angle to be as steady as possible. Eg With zero sideslip the AoA was 12 at buffet onset, 13.5 at first lateral stick snatch, 15 when the nose dropped or 16 when the stick reached fully back (or whatever all the numbers/events are as the ones I have quoted above are of no significance whatsoever)
If you allow me to bang on a bit longer about flight test techniques I hope it will become clear why I later say what I do about topic B.
A comprehensive stalling flight test programme requires a huge number of different stalls to be flown. There will be one set for each configuration typically TE flap angle LE device setting (if fitted as they say in the car handbooks) undercarriage position and most importantly they will all have to be looked at under different power settings to say nothing of CG, weight and altitude. If your aircraft can exceed about Mach 0.5 then throw in a whole lot more at different mach numbers.
But that is FAR from the end of the flight test stall programme. Once that is done there will be many more stall entries to be done with a rapid onset of angle of attack (now we are starting to get to the case B above)
Here the tp wants to establish what will happen in the unsteady case and is covering the flying club type of training stall or if you like the way a pilot might accidently blunder into an inadvertent stall. Necessarily if you close the throttle in level flight and then hold your height your airspeed will reduce quite quickly and very importantly your angle of attack will increase ever more quickly. Indeed this approach will likely produce quite a big AoA overshoot once the stall happens and before the student starts the recovery. The IAS will likely get to a silly low value and whatever reading it gets down to is likely to be pretty meaningless due to unknown pressure errors in these transient conditions.
So if you speak to a tp and he mutters about œ to 1 kt/sec and also says he ignores the flight path (which does not affect the airflow round the wing) he is talking about how he gets this nearly steady data and is not describing the stalling programme just one aspect of it.
Finally any flight test programme fully takes into account the role for which the aircraft will be used. So Cirrus there is no mismatch between what you were taught and what goes on in flight test. Happier?
I could also go on about how you keep stalling flight tests safe (they are by definition being done for the first time) but this post is too long already and there are books on all this.
John.F, everything you say is great, except...
... I'm afraid that in my experience the developers and certifiers of light civil aircraft commonly do not fly the sort of extensive test programmes that you are describing.
Here's an example, absolutely true, I'll simply keep the aircraft type to myself.
A few years ago I was asked to go and evaluate a highish performance light aeroplane being manufactured by *****, a small but well regarded company based "somewhere in Eastern Europe". The company held national and German approvals (at the time EASA was still a figment of somebody's deranged imagination - perhaps it still is) and was exporting aeroplanes to a large number of countries.
As part of my assessment I obviously wanted to look at the stall, and as part of the preparation I'd been through all of the company FT reports they'd give me. The company summary was very clear: stall at 64kph, no wing drop, no tendency to spin.
So, there I am - lots of height, spin recovery briefed (I'm not completely daft!), and agreed with my safety pilot (who happened to also be the chief designer) that I'd fly a power-off wings level stall. So, standard stuff - trim to about 1.3Vs, power to idle, keeping the ball in the middle decelerate slowly at about 2kph/s, small control inputs to check effectiveness every 10kph or so... And so, 66, 65, 64, 63, 62, INCIPIENT SPIN. So, I recovered that, and said to my safety pilot "hmmm, that was interesting" (or words to that effect), who agreed and asked me not to do it again.
Debrief points: the company TPs had to meet a local certification requirement that Vs0<=65kph, with no more than 20° of wing drop, and no tendency to spin. So, they'd slowed to 64kph - at which point the aeroplane was clearly still flying unstalled, but chosen to declare that as the stall speed. AND THIS HAD THEN BEEN CERTIFIED IN THREE COUNTRIES LIKE THAT - all of whom I'd regard(ed!) as above averagely competent in aeronautics. And, unwittingly, I was probably the first pilot to take this aeroplane to the aerodynamic stall. (Good news, when it was finally certified in the UK, it had been properly tested and now has, I understand, quite benign stalling characteristics!)
I can think of other instances on part 23 or smaller aeroplanes, but I'm afraid that in my experience the pattern is fairly consistent - certifying authorities do not insist on the sort of thorough assessment that you are describing - and whilst not all, there are companies who will do the minimum to tick the boxes of the certification standard - and in several countries I've worked in (including, sadly, the UK), the national authority will defend and support their decision to work that way.
Having said that, I absolutely agree that a competent military flight test organisation such as CEV or AČEČ will certainly make sure that any stalling assessment carried out is thorough and role-related (so far as they use test pilots with the right role knowledge, which is probably easier for them in a combat than a training aeroplane), and also that this "big grid" isn't going to be there for a quick qualeval which is what CirrusF seems to be describing flying in the DA42, where an idle 1kn/s, high RoD stall is likely the major test point in a short but busy sortie.
G
... I'm afraid that in my experience the developers and certifiers of light civil aircraft commonly do not fly the sort of extensive test programmes that you are describing.
Here's an example, absolutely true, I'll simply keep the aircraft type to myself.
A few years ago I was asked to go and evaluate a highish performance light aeroplane being manufactured by *****, a small but well regarded company based "somewhere in Eastern Europe". The company held national and German approvals (at the time EASA was still a figment of somebody's deranged imagination - perhaps it still is) and was exporting aeroplanes to a large number of countries.
As part of my assessment I obviously wanted to look at the stall, and as part of the preparation I'd been through all of the company FT reports they'd give me. The company summary was very clear: stall at 64kph, no wing drop, no tendency to spin.
So, there I am - lots of height, spin recovery briefed (I'm not completely daft!), and agreed with my safety pilot (who happened to also be the chief designer) that I'd fly a power-off wings level stall. So, standard stuff - trim to about 1.3Vs, power to idle, keeping the ball in the middle decelerate slowly at about 2kph/s, small control inputs to check effectiveness every 10kph or so... And so, 66, 65, 64, 63, 62, INCIPIENT SPIN. So, I recovered that, and said to my safety pilot "hmmm, that was interesting" (or words to that effect), who agreed and asked me not to do it again.
Debrief points: the company TPs had to meet a local certification requirement that Vs0<=65kph, with no more than 20° of wing drop, and no tendency to spin. So, they'd slowed to 64kph - at which point the aeroplane was clearly still flying unstalled, but chosen to declare that as the stall speed. AND THIS HAD THEN BEEN CERTIFIED IN THREE COUNTRIES LIKE THAT - all of whom I'd regard(ed!) as above averagely competent in aeronautics. And, unwittingly, I was probably the first pilot to take this aeroplane to the aerodynamic stall. (Good news, when it was finally certified in the UK, it had been properly tested and now has, I understand, quite benign stalling characteristics!)
I can think of other instances on part 23 or smaller aeroplanes, but I'm afraid that in my experience the pattern is fairly consistent - certifying authorities do not insist on the sort of thorough assessment that you are describing - and whilst not all, there are companies who will do the minimum to tick the boxes of the certification standard - and in several countries I've worked in (including, sadly, the UK), the national authority will defend and support their decision to work that way.
Having said that, I absolutely agree that a competent military flight test organisation such as CEV or AČEČ will certainly make sure that any stalling assessment carried out is thorough and role-related (so far as they use test pilots with the right role knowledge, which is probably easier for them in a combat than a training aeroplane), and also that this "big grid" isn't going to be there for a quick qualeval which is what CirrusF seems to be describing flying in the DA42, where an idle 1kn/s, high RoD stall is likely the major test point in a short but busy sortie.
G
Do a Hover - it avoids G
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I guess the world is not perfect Genghis - no matter what area of professional behaviour one looks at.
Returning to the specifics of stalling in the GA community I really do wish that QFIs did demo the gentle and very easy flight test approach before putting students through the 'close the throttle fly level and recover when it stalls' manoeuvre. In my view the latter can result in quite an off-putting experience for a low hour student.
Returning to the specifics of stalling in the GA community I really do wish that QFIs did demo the gentle and very easy flight test approach before putting students through the 'close the throttle fly level and recover when it stalls' manoeuvre. In my view the latter can result in quite an off-putting experience for a low hour student.
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Clearly a case where the real world and the flight test world don't speak quite the same language.
There's a whole lot of issues that could be raised about the stall techniques used for testing and those used in the real world. Some of the recent turbo-prop accidents in the US have shown how different the two worlds are.
(and this problem is not just in the FW world - the helicopter world has a number of differences between certification and real world as well)
There's a whole lot of issues that could be raised about the stall techniques used for testing and those used in the real world. Some of the recent turbo-prop accidents in the US have shown how different the two worlds are.
(and this problem is not just in the FW world - the helicopter world has a number of differences between certification and real world as well)
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So what's the point of your story, Genghis, with respect to the original question?
You flew the aircraft in the traditional manner (just like the French pilot in the question) to determine a certification stall speed and found that the company had apparently not done this correctly. This is obviously not good but I do not see what relevance it has to the original question, as to why the French test pilot may have flown the stall in that manner.
John has of course described the two approaches to stall testing and the reasons for them very well.
Test pilots are taught how to conduct stall testing and determine stall speeds for civil certification or military airworthiness. They are also taught the importance of conducting suitable 'role relatable' testing on any type of aircraft they might fly.
Your insistence on turning any point like this back to your favourite subject of how military test pilots are unsuitable to test light aircraft because they dont know enough about it (or they're not an FI!)is a little boring, and probably quite irrelevant to the original question in this case.
You flew the aircraft in the traditional manner (just like the French pilot in the question) to determine a certification stall speed and found that the company had apparently not done this correctly. This is obviously not good but I do not see what relevance it has to the original question, as to why the French test pilot may have flown the stall in that manner.
John has of course described the two approaches to stall testing and the reasons for them very well.
Test pilots are taught how to conduct stall testing and determine stall speeds for civil certification or military airworthiness. They are also taught the importance of conducting suitable 'role relatable' testing on any type of aircraft they might fly.
Your insistence on turning any point like this back to your favourite subject of how military test pilots are unsuitable to test light aircraft because they dont know enough about it (or they're not an FI!)is a little boring, and probably quite irrelevant to the original question in this case.
I'm sorry if that's what you thought I was doing Tester 07, I thought I'd got that out of my system a long time ago and certainly didn't intend to make the points you think I am.
My points:
(1) What John says about a complete stalling test grid is a valid description of good practice; but, in my experience a lot of the light aircraft industry doesn't do it that way - often the minimum needed to show standard compliance is all that's done, and that with a certain amount of gamesmanship.
(2) Role relation is very important and flight testers used to one type of flying may need to "buy in" a bit of role relation knowledge when testing for a different role.
(3) The test described by the OP was a standard certification stall, not a role-related test. Both are needed.
(4) There is a mismatch between civil certification standards and the way training aeroplanes are actually flown in deliberate stalling. This is compounded by flight testers in the civil industry who don't construct the sort of thorough test grid that would be normal in the military world.
To be honest, I don't think that you can really accuse my...
Of being a criticism of military (trained) TPs. My main criticism was of civil certification practice which DOES NOT necessarily apply the rigour, and particularly role-relation, that would be normal to a military-trained flight tester.
And yes, I digressed from the original question - but I'm not alone in that!
Also, for the record, most - quite possibly all - of the key decision makers in the organisations that I'm criticising are not military trained TPs or FTEs.
G
My points:
(1) What John says about a complete stalling test grid is a valid description of good practice; but, in my experience a lot of the light aircraft industry doesn't do it that way - often the minimum needed to show standard compliance is all that's done, and that with a certain amount of gamesmanship.
(2) Role relation is very important and flight testers used to one type of flying may need to "buy in" a bit of role relation knowledge when testing for a different role.
(3) The test described by the OP was a standard certification stall, not a role-related test. Both are needed.
(4) There is a mismatch between civil certification standards and the way training aeroplanes are actually flown in deliberate stalling. This is compounded by flight testers in the civil industry who don't construct the sort of thorough test grid that would be normal in the military world.
To be honest, I don't think that you can really accuse my...
I absolutely agree that a competent military flight test organisation such as CEV or AČEČ will certainly make sure that any stalling assessment carried out is thorough and role-related
And yes, I digressed from the original question - but I'm not alone in that!
Also, for the record, most - quite possibly all - of the key decision makers in the organisations that I'm criticising are not military trained TPs or FTEs.
G
I think it is important to point out to the original poster that there really are two distinct phases to stall testing:
a. Establish the stall handling qualities, which was the original query, for the many configurations and flight conditions required for certification (ie straight, turning, low/high approach rate, sideslip, high power, etc).
b. Establish the stall speeds which are required as the basis for other performance speeds.
This may be far from a straightforward exercise with an aircraft which appears to be stalling at around the maximum speed permitted by the certification standard yet may need handling fixes which could result in an even higher stall speed.
a. Establish the stall handling qualities, which was the original query, for the many configurations and flight conditions required for certification (ie straight, turning, low/high approach rate, sideslip, high power, etc).
b. Establish the stall speeds which are required as the basis for other performance speeds.
This may be far from a straightforward exercise with an aircraft which appears to be stalling at around the maximum speed permitted by the certification standard yet may need handling fixes which could result in an even higher stall speed.
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Just goes to show that a little knowledge can be a 'dangerous' thing. Perhaps, not dangerous in the accepted sense of the word, but it does show that there are them that really know and them that nearly know. I am sure you know what I mean.
Simple really. But...........I'll have Dunne to Farley et al any day of the week.
Simple really. But...........I'll have Dunne to Farley et al any day of the week.
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Surrey Towers
OK, I will be the brave one then and rise to the bait since no-one else is going to stick their head above the parapet and admit it. I don't understand!
"I'll have Dunne to Farley et al any day of the week"?
OK, I will be the brave one then and rise to the bait since no-one else is going to stick their head above the parapet and admit it. I don't understand!
"I'll have Dunne to Farley et al any day of the week"?
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I thought everyone knew that.....J W Dunne, worked out the design for a swept back wing biplane, and built it - in circa 1907. A very clever and brilliant engineer.
In between times the seemingly endless list of the brilliant best of test pilots came and went (indeed, often killed). In my view I think I am right when I say that unless John Farley had not been so skilled as an engineer, as well as a pilot, the Harrier would never have been born.
From Dunne to Farley encapsulates the whole of the major flight testing years - for me at least.
In between times the seemingly endless list of the brilliant best of test pilots came and went (indeed, often killed). In my view I think I am right when I say that unless John Farley had not been so skilled as an engineer, as well as a pilot, the Harrier would never have been born.
From Dunne to Farley encapsulates the whole of the major flight testing years - for me at least.
A bit simplistic I'd have thought.
So far as I know, John Farley, whilst a thoroughly talented chap who has done much for British aviation - and continues to, is neither (a) dead, nor (b) designer of the Harrier.
G
So far as I know, John Farley, whilst a thoroughly talented chap who has done much for British aviation - and continues to, is neither (a) dead, nor (b) designer of the Harrier.
G
Join Date: Jun 2008
Location: London
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Genghis, where did I say that JF was dead? Where did I say he designed the Harrier? That was done by Dr John Fozard and his team.
However, John Farley's own engineering background, and his flying skills, was a significant factor in its devlopment.
Credit where credit is due.
However, John Farley's own engineering background, and his flying skills, was a significant factor in its devlopment.
Credit where credit is due.