PPL- Spin Training
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From: Suffolk
Pace asked:
The answer depends on the glider model, but in general airbrakes are problematic near VNE. They change the lift distribution, killing lift at the root (the strong part) and transferring the load to the tips (weaker). This is more marked the longer the wings.
A few years ago a 25m (or so) glider broke up (flying in the US or the French Apls, or maybe there were two similar cases) when the pilot oversped ona recovery and deployed the brakes.
If deployed earlier they can be speed limiting, or at least help slow the acceleration.
One question I have is concerning air brakes!
Are those speed limited or are they good to VNE and beyond. In the Citation I fly the speed brakes are good throughout the speed range.
Is that the same in a glider and would use of speedbrakes be more comfortable for the pilot rather than using high G pulls to slow down.
That of course also depends on how effective the speed brakes are?
Are those speed limited or are they good to VNE and beyond. In the Citation I fly the speed brakes are good throughout the speed range.
Is that the same in a glider and would use of speedbrakes be more comfortable for the pilot rather than using high G pulls to slow down.
That of course also depends on how effective the speed brakes are?
A few years ago a 25m (or so) glider broke up (flying in the US or the French Apls, or maybe there were two similar cases) when the pilot oversped ona recovery and deployed the brakes.
If deployed earlier they can be speed limiting, or at least help slow the acceleration.
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From: In the boot of my car!
ProfChrisReed
We discussed a while back the use of mode C on Gliders and possible power sources.
One was a fusealage mounted fan generator which although tiny was discounted for the huge drag it would create on a glider.
Due to the Gliders long wings and the problems you mention are there any with fusealage mounted brakes?
Pace
We discussed a while back the use of mode C on Gliders and possible power sources.
One was a fusealage mounted fan generator which although tiny was discounted for the huge drag it would create on a glider.
Due to the Gliders long wings and the problems you mention are there any with fusealage mounted brakes?
Pace
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From: 75N 16E
I think Vne is very badly understood by most pilots, and is based on numerous things, including engine power as it is based upon True airspeed (i.e. the speed of the air molecules over the surfaces, not the volume) - So if you decide to replace your Vans O320 engine with a TO540 engine, you could well achieve above Vne at altitude despite being below Vne on the ASI - because when the aeroplane was first certified the numbers on the dial were calculated so that Vne could never be reached in normal operations. In other words engine power self limited Vne..
Vne scares me more because it was determined in a nice new aeroplane. A bit of slop in the hinges and if the flutter starts your aeroplane could destroy itself in seconds. One can manage G to some extent.
Personally I'd never spin a C152 which is 40 years old. I'd rather be in a CAP10 with a aero's FI sat beside me.
Vne scares me more because it was determined in a nice new aeroplane. A bit of slop in the hinges and if the flutter starts your aeroplane could destroy itself in seconds. One can manage G to some extent.
Personally I'd never spin a C152 which is 40 years old. I'd rather be in a CAP10 with a aero's FI sat beside me.
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From: Ontario, Canada
Vne scares me more because it was determined in a nice new aeroplane. A bit of slop in the hinges and if the flutter starts your aeroplane could destroy itself in seconds. One can manage G to some extent.
Personally I'd never spin a C152 which is 40 years old. I'd rather be in a CAP10 with a aero's FI sat beside me.
Personally I'd never spin a C152 which is 40 years old. I'd rather be in a CAP10 with a aero's FI sat beside me.
For general aiviation airframes, with few execptions, airworthiness is based upon condition, evaluated against a standard established by the original manufacturer, relative to a "new" aircraft.
It's sorta like: "dimension x for intstallation of a new part, must be between a and b, in service, that dimension may be as much as c, and the aircraft is still airworthy" If it is tighter than "a", it is not airworthy (though some installation rework might be possible), if it is more loose than "b", don't install it. If, during inspection, you find it between "b" and "c", it's okay to leave it in service - IT IS AIRWORTHY, if it is beyond "c", replacement is required.
If, at the time of development of the original instructions for continued airworthiness, something important was missed, and problems in service began to pop up, there are many tools (Serivce Bulletins through to AD's) to catch this. That is a reason I like 40 year old planes (mines only 36), they have the in service experience to figure out where the problems are!
If it is your preference to not spin a 40 year old plane, I suggest that you not fly it at all, because to think that a spin (presuming it is spin approved) causes stress on the structure, or risk of flutter, which otherwise would not be encountered, is head in the sand thinking.
If you are willing to pay the price, and/or make other operational compromises, to assure that you are always flying "new" planes, that's perfectly fine. Other pilots choose either by preference, economy, or operational need, to fly older airplanes. As long as those aircraft are maintained airworthy, there is no reason to consider them any less safe or capable than "new" ones, when operated safely within their limitations.
As for powerplant, Vne is not power dependent. None of the times I have flown to speeds exceeding Vne (Vd) have required full power. I always use some, just to be kind to the engine cooling. Vne is based upon and limited by indicated airspeed in light aircraft. I have flown aircraft which are capable of exceeding Vne in level flight with high power settings. You just don't do that! (oher than for testing purposes).
As Vne is limited by indicated airspeed for light GA types, as long as the airspeed indicator is not past the red line, you are not going too fast in that plane, regarless of altitude or the engine installed. When Mach begins to be a factor, the airspeed indicators are equipped with moving "barberpole" redlines (with which I have limited experience).
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From: 75N 16E
As for powerplant, Vne is not power dependent. None of the times I have flown to speeds exceeding Vne (Vd) have required full power. I always use some, just to be kind to the engine cooling. Vne is based upon and limited by indicated airspeed in light aircraft. I have flown aircraft which are capable of exceeding Vne in level flight with high power settings. You just don't do that! (oher than for testing purposes).
Many pilots assume that operating at high altitude
(greater than 12,500 ft, say), even with the increased
power supplied by a turbocharger, will not be a problem
if the mechanical problems are solved. Sure, they
can go faster, but not so much faster that they exceed
the limitations marked in living color on the airspeed
indicator. How, they ask with apparently perfect logic,
can the airplane be exceeding Vne if the needle is in......
the green arc?
Because the airspeed indicator is The Gauge That
Lies. Despite its name, an airspeed indicator does not
measure speed. It measures “q” – dynamic pressure
caused by packing air molecules into a tube. Now,
several limiting speeds like stall speed (bottom of the
green and white arcs), gust loads (top of the green
arc), and maneuvering speed (blue line) are also functions
of q, so they may be read directly off the dial. In
these cases, the logic is true.
This logic is NOT true for the very important red
line at the top of the yellow arc. Here’s why:
Consider an aircraft flying in smooth air at cruise
speed. The aircraft structure is then slightly disturbed
(such as by turbulence). In response, the aircraft structure
will oscillate with amplitude decreasing until the
oscillation stops altogether. This dynamically stable
response is due to damping acting on the system, either
from the aircraft structure and/or air. If the cruise
speed is incrementally increased there will be a particular
speed at which the amplitude of structural oscillation
will remain constant. The speed at which constant
amplitude oscillation can be first maintained is
defined as the “critical flutter speed”, or more generi-
cally “flutter speed”. Flutter is almost a pretty word.
You’d associate it with butterflies and silk handkerchiefs.
But in the engineering sense, it can be highly
destructive. Once flutter has started, the amplitude
may quickly become so large that a structure will disintegrate,
literally shaken to pieces.
Remember, as the airplane climbs, there are
fewer air molecules and less air pressure, so the needle
on The Gauge That Lies reads a lower speed,
even though the airplane is actually going just as
fast. That’s why True airspeed is faster than Indicated.
But flutter does not depend on Indicated Air
Speed/dynamic pressure. It is directly related to True
Air Speed — the velocity of the air passing by the airframe.
The velocity of the excitation force is the prime
concern, not the magnitude. It is very possible to exceed
this critical “flutter speed” without encountering
flutter if there is no initial disturbance. But if the critical
flutter speed is exceeded and then a disturbance
is encountered, the aircraft structure will begin to oscillate
in response to the velocity of the passing air.
This is not a typical resonance, where either increasing
or decreasing the speed will move the aircraft
away from the critical frequency and the vibration will
stop on its own. Going faster merely pumps more energy
into the system, increasing the amplitude of the
flutter. Go faster, flutter harder. Only going slower
and lowering the velocity of the air over the airframe
will solve the problem.
....
(greater than 12,500 ft, say), even with the increased
power supplied by a turbocharger, will not be a problem
if the mechanical problems are solved. Sure, they
can go faster, but not so much faster that they exceed
the limitations marked in living color on the airspeed
indicator. How, they ask with apparently perfect logic,
can the airplane be exceeding Vne if the needle is in......
the green arc?
Because the airspeed indicator is The Gauge That
Lies. Despite its name, an airspeed indicator does not
measure speed. It measures “q” – dynamic pressure
caused by packing air molecules into a tube. Now,
several limiting speeds like stall speed (bottom of the
green and white arcs), gust loads (top of the green
arc), and maneuvering speed (blue line) are also functions
of q, so they may be read directly off the dial. In
these cases, the logic is true.
This logic is NOT true for the very important red
line at the top of the yellow arc. Here’s why:
Consider an aircraft flying in smooth air at cruise
speed. The aircraft structure is then slightly disturbed
(such as by turbulence). In response, the aircraft structure
will oscillate with amplitude decreasing until the
oscillation stops altogether. This dynamically stable
response is due to damping acting on the system, either
from the aircraft structure and/or air. If the cruise
speed is incrementally increased there will be a particular
speed at which the amplitude of structural oscillation
will remain constant. The speed at which constant
amplitude oscillation can be first maintained is
defined as the “critical flutter speed”, or more generi-
cally “flutter speed”. Flutter is almost a pretty word.
You’d associate it with butterflies and silk handkerchiefs.
But in the engineering sense, it can be highly
destructive. Once flutter has started, the amplitude
may quickly become so large that a structure will disintegrate,
literally shaken to pieces.
Remember, as the airplane climbs, there are
fewer air molecules and less air pressure, so the needle
on The Gauge That Lies reads a lower speed,
even though the airplane is actually going just as
fast. That’s why True airspeed is faster than Indicated.
But flutter does not depend on Indicated Air
Speed/dynamic pressure. It is directly related to True
Air Speed — the velocity of the air passing by the airframe.
The velocity of the excitation force is the prime
concern, not the magnitude. It is very possible to exceed
this critical “flutter speed” without encountering
flutter if there is no initial disturbance. But if the critical
flutter speed is exceeded and then a disturbance
is encountered, the aircraft structure will begin to oscillate
in response to the velocity of the passing air.
This is not a typical resonance, where either increasing
or decreasing the speed will move the aircraft
away from the critical frequency and the vibration will
stop on its own. Going faster merely pumps more energy
into the system, increasing the amplitude of the
flutter. Go faster, flutter harder. Only going slower
and lowering the velocity of the air over the airframe
will solve the problem.
....
Regarding old aeroplanes, we have just finished rebuilding a Commander that was going to be scrapped after a landing accident. I am glad we had the thing completely to pieces as we found corrosion in one of the rudder hinges and due to the location it would NEVER have been found had the rudder not been removed, which typically they are not unless there is a problem. We probably would have noticed when the hinge had broken.
As you are so trusting, you should also read:
AOPA Online: Never Again Online: Denali's rough ride
which describes a flutter incident in the Beaver
The FAA engineering team concluded that one aileron was 17 ounces out of balance and there was possibly a 0.003 discrepancy in a wing bushing that, when amplified to the length of the wing, was a contributing factor. General maintenance would not have detected this — everything was current and legal.
An FAA inspector who did the investigation stated — with no supporting data — that I had exceeded the aircraft's VNE speed and caused this to happen, a statement that caused me considerable hardship. I have since been totally exonerated from any wrongdoing, and I actually have been credited with a save of the three lives and my own, with my correct and swift response to the emergency.
Flutter is a very dangerous event, and any indication should be dealt with seriously. I'm glad that I was able to act quickly and nurse the aircraft back to a safe landing. I've also learned several important lessons.
An FAA inspector who did the investigation stated — with no supporting data — that I had exceeded the aircraft's VNE speed and caused this to happen, a statement that caused me considerable hardship. I have since been totally exonerated from any wrongdoing, and I actually have been credited with a save of the three lives and my own, with my correct and swift response to the emergency.
Flutter is a very dangerous event, and any indication should be dealt with seriously. I'm glad that I was able to act quickly and nurse the aircraft back to a safe landing. I've also learned several important lessons.
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From: Suffolk
Pace asked:
Not currently in production. The first production glass glider (the Phoenix, back in the late 50s) had a sort of belly flap which apparently worked OK. Trailing edge airbrakes have been used, which are pure drag devices.
However, as glider performance improved, the difficulties of getting back on the ground also increased. Thus most need to have lift-killing brakes, as Mark1234 noted, to reduce the gide angle from 50:1 to a more manageable 8:1 or so. They've also been found to be most easily manageable for the pilot in practice.
As always in aviation, a trade-off (in this case between performance/handling and potential structural compromise). I think a reasonable one - many more gliders are broken through overshooting than through structural failure from all causes.
Going beyond VNE in a glider is potentially more dangerous than in a short wing a/c because of the risk of flutter - long and flexible wings are ideal for this purpose. Thus Mary's earlier point about pulling G rather than exceeding VNE, as flutter is more likely to break bits off than over-stressing. In extremis only, of course, and you may be unable to re-use the aircraft.
Due to the Gliders long wings and the problems you mention are there any with fusealage mounted brakes?
However, as glider performance improved, the difficulties of getting back on the ground also increased. Thus most need to have lift-killing brakes, as Mark1234 noted, to reduce the gide angle from 50:1 to a more manageable 8:1 or so. They've also been found to be most easily manageable for the pilot in practice.
As always in aviation, a trade-off (in this case between performance/handling and potential structural compromise). I think a reasonable one - many more gliders are broken through overshooting than through structural failure from all causes.
Going beyond VNE in a glider is potentially more dangerous than in a short wing a/c because of the risk of flutter - long and flexible wings are ideal for this purpose. Thus Mary's earlier point about pulling G rather than exceeding VNE, as flutter is more likely to break bits off than over-stressing. In extremis only, of course, and you may be unable to re-use the aircraft.
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From: Ontario, Canada
Englishal,
It seems to me that your examples cite aircraft, which I would agree, sound to not be "airworthy" (conforming to their type design, and in safe condition). My argument does not extend to unairworthy aircraft.
When I rebilt a Thorpe T-18 years ago, the fine fit of the stabiliator pivot was of critical importance. I used an adjustable reamer to assure a bushing fit of better than 0.0005" tolerance, so as to prevent a loose fit there being a source of flutter.
Yes, if a flight control is out of balance, or a bushing is loose, flutter can happen very quickly, and with horrendous results. For anyone who has not seen it, allow me to link the following....
As for airspeeds, I cannot speak to limitations for Vans aircraft, other than to say that I am not aware of Van's aircraft having demonstrated compliance for certification - but I could be wrong.
For certified "slow" GA aircraft, operating at their normal altitudes, the following Wikipedia passage would describe why Vne in IAS is Vne. A pilot does not have to worry about exceeding safe maximum speeds, while still flying at an IAS of less than Vne.
"The IAS is an important value for the pilot because it directly indicates stall speed and various airframe structurally limited speeds, regardless of density altitude."
It seems to me that your examples cite aircraft, which I would agree, sound to not be "airworthy" (conforming to their type design, and in safe condition). My argument does not extend to unairworthy aircraft.
When I rebilt a Thorpe T-18 years ago, the fine fit of the stabiliator pivot was of critical importance. I used an adjustable reamer to assure a bushing fit of better than 0.0005" tolerance, so as to prevent a loose fit there being a source of flutter.
Yes, if a flight control is out of balance, or a bushing is loose, flutter can happen very quickly, and with horrendous results. For anyone who has not seen it, allow me to link the following....
As for airspeeds, I cannot speak to limitations for Vans aircraft, other than to say that I am not aware of Van's aircraft having demonstrated compliance for certification - but I could be wrong.
For certified "slow" GA aircraft, operating at their normal altitudes, the following Wikipedia passage would describe why Vne in IAS is Vne. A pilot does not have to worry about exceeding safe maximum speeds, while still flying at an IAS of less than Vne.
"The IAS is an important value for the pilot because it directly indicates stall speed and various airframe structurally limited speeds, regardless of density altitude."
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From: Suffolk
Pilor DAR wrote:
Not so!
Vne is a TAS value, not an IAS value. For practical purposes at lower altitudes they can be treated as roughly the same. However, at high altitudes this becomes critical. Gliders regularly fly in in wave above 30,000 ft, and there the IAS value for Vne is substantially lower and needs to be known and respected.
[Edited to add: Wikipedia says "various" airspeeds for structural limitations. Those for gust factors etc remain unchanged, because they are related to the stall speed, but the flutter limitations are TAS based.
A pilot does not have to worry about exceeding safe maximum speeds, while still flying at an IAS of less than Vne.
Vne is a TAS value, not an IAS value. For practical purposes at lower altitudes they can be treated as roughly the same. However, at high altitudes this becomes critical. Gliders regularly fly in in wave above 30,000 ft, and there the IAS value for Vne is substantially lower and needs to be known and respected.
[Edited to add: Wikipedia says "various" airspeeds for structural limitations. Those for gust factors etc remain unchanged, because they are related to the stall speed, but the flutter limitations are TAS based.
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From: Ontario, Canada
Aw, c'mon, if you're going to quote me, at least quote me in context.....
I did say "For certified "slow" GA aircraft, operating at their normal altitudes....."
I would not include a glider operating at 30,000 feet in this category! Yes, I do realize the TAS/IAS relationship. For your average single engined, light aircraft flying below 10,000 feet, the TAS/IAS relationship is not going to affect Vne in any meaningful way. Were it to be so, it would be a design requirment that TAS be displayed to the pilot, for the purpose of defining Vne. It was on the Piper PA-31T used to fly at 25,000 feet all those years ago! Not on a PA 28-161....
As this is a thread about spin training PA-28-161, I suggest that dramatic remarks about flutter, TAS/IAS and high performance sailplanes is rather out of place here! Would somome like to start a new thread for this extreme performance discussion?
I did say "For certified "slow" GA aircraft, operating at their normal altitudes....."
I would not include a glider operating at 30,000 feet in this category! Yes, I do realize the TAS/IAS relationship. For your average single engined, light aircraft flying below 10,000 feet, the TAS/IAS relationship is not going to affect Vne in any meaningful way. Were it to be so, it would be a design requirment that TAS be displayed to the pilot, for the purpose of defining Vne. It was on the Piper PA-31T used to fly at 25,000 feet all those years ago! Not on a PA 28-161....
As this is a thread about spin training PA-28-161, I suggest that dramatic remarks about flutter, TAS/IAS and high performance sailplanes is rather out of place here! Would somome like to start a new thread for this extreme performance discussion?
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From: Amsterdam
Here we go. Vne, flutter and their effect on transonic gliders at 30.000'. I can't wait.
(We're on page 5 of this thread. That's roughly the place where a thread drift is mandatory. Unless the thread is about Oban...
)
(We're on page 5 of this thread. That's roughly the place where a thread drift is mandatory. Unless the thread is about Oban...
)
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From: Suffolk
We;re not talking transonic gliders here, and 30,000 ft is not abnormal operations.
If you want a more realistic example, take a glider with a Vne of 120kt operating at 15,000 ft (commonplace in the Western US, Australia, New Zealand, the Alps, South Africa, and in Scotland and Wales in the UK).
An online calculator tells me that an IAS of 120kt translates into a TAS of 156kt. That;s way beyond what an airframe (brand new) has been tested to (135kt) and is probably into flutter and structural damage territory.
If you want a more realistic example, take a glider with a Vne of 120kt operating at 15,000 ft (commonplace in the Western US, Australia, New Zealand, the Alps, South Africa, and in Scotland and Wales in the UK).
An online calculator tells me that an IAS of 120kt translates into a TAS of 156kt. That;s way beyond what an airframe (brand new) has been tested to (135kt) and is probably into flutter and structural damage territory.
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From: In the boot of my car!
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From: Ontario, Canada
In reviewing the FAA approved flight manual for a 1978 Cessna 210 (and aircraft certainly capable of getting into the part of the sky where IAS/TAS split noticably), the limitations clearly say that Vne is a speed in "KIAS". Cessna had the opportunity to define KTAS as the limiting speed measure, but met the design requirement with IAS. Therefore, I would agree that you could have well exceeded the speed number in TAS before you reached Vne in IAS - an that is obviously permitted!
By the way, as a further thread drift, and purely for my education, what is an "LAA" aircraft? I prsume it has an approved flight manual, with a limitations section?
By the way, as a further thread drift, and purely for my education, what is an "LAA" aircraft? I prsume it has an approved flight manual, with a limitations section?
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From: UK
LAA = Light Aircraft Association, formerly known as the Popular Flying Association. An LAA aircraft is a sub-ICAO aeroplane, certified for operation in the UK by the LAA. The organisation has a similar, but not identical, role to EAA in the USA. Pretty much anything that in other countries would be "Experimental" or "Homebuilt" along with a lot of simpler vintage aeroplanes - although not the majority of microlights (2 seaters up to 450kg MTOW and single seaters up to 300kg in the UK) come under LAA.
The rules require that they have approved operators manuals, in many cases however they don't because LAA don't think this is necessary. I believe that, in this regard, LAA is wrong. To be fair, their policy on this does seem to have changed in the last couple of years; I tested a vintage aeroplane for them last year, and the approach taken to operating data was very thorough.
LAA do, to be fair, publish a set of operating limits which must be placarded. These might, on the other hand, have more credibility, if they ever determined the PECs for their aircraft which, in the vast majority of cases, they don't. In this regard, I also think that LAA is wrong; their policy on this doesn't seem to have changed that I'm aware of.
ProfChrisReed is incorrect in stating that Vne is declared in TAS; it is, like most other V speeds, normally declared in IAS. However, if it is determined by flutter onset, then this is a function of TAS, for which reason it may be necessary in some aeroplanes to vary Vne with altitude. This isn't however often done, in which regard, I think that many of the engineers certifying gliders are probably also wrong.
G
The rules require that they have approved operators manuals, in many cases however they don't because LAA don't think this is necessary. I believe that, in this regard, LAA is wrong. To be fair, their policy on this does seem to have changed in the last couple of years; I tested a vintage aeroplane for them last year, and the approach taken to operating data was very thorough.
LAA do, to be fair, publish a set of operating limits which must be placarded. These might, on the other hand, have more credibility, if they ever determined the PECs for their aircraft which, in the vast majority of cases, they don't. In this regard, I also think that LAA is wrong; their policy on this doesn't seem to have changed that I'm aware of.
ProfChrisReed is incorrect in stating that Vne is declared in TAS; it is, like most other V speeds, normally declared in IAS. However, if it is determined by flutter onset, then this is a function of TAS, for which reason it may be necessary in some aeroplanes to vary Vne with altitude. This isn't however often done, in which regard, I think that many of the engineers certifying gliders are probably also wrong.
G
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From: Suffolk
Ghengis wrote:
Interesting - I wasn't aware of that, so thanks.
The UK glider training tells us to treat Vne as a TAS value because of the flutter risks, which must be why I thought that was how it was as standard expressed. This is contrasted in the training with Vs, which we are told remains the same as an IAS irrespective of altitude.
ProfChrisReed is incorrect in stating that Vne is declared in TAS; it is, like most other V speeds, normally declared in IAS. However, if it is determined by flutter onset, then this is a function of TAS, for which reason it may be necessary in some aeroplanes to vary Vne with altitude. This isn't however often done, in which regard, I think that many of the engineers certifying gliders are probably also wrong.
The UK glider training tells us to treat Vne as a TAS value because of the flutter risks, which must be why I thought that was how it was as standard expressed. This is contrasted in the training with Vs, which we are told remains the same as an IAS irrespective of altitude.
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From: 75N 16E
The reason Vne can be shown on the ASI as an IAS is because in that design configuration, the aeroplane will never get anywhere near Vne in level flight due to the power self limiting properties of the engine in relation to altitude (where TAS departs IAS considerably). So in a TB20, with say a Vne of 180 kts IAS (just made that up by the way), likely at FL200 you will show 100 kts IAS. This 100 Kts IAS will be less than the Vne at 140 kts TAS.
However what Vans were warning about, is those who insist on taking an RV6 (for example) and changing out the IO360 with say a TIO360.
Now the aeroplane has a turbo charger and can hence develop much more power at high altitude, which = > IAS. Even though s(he) may be travelling at 150Kts IAS which is well below the indicated Vne of 180 kts (made that up too) the TAS is 210 Kts which is > Vne by 30kts !
Gliders are different animals obviously as they don't have an engine to deliver less power at alt, which is why the obviously have Vne tables.
However what Vans were warning about, is those who insist on taking an RV6 (for example) and changing out the IO360 with say a TIO360.
Now the aeroplane has a turbo charger and can hence develop much more power at high altitude, which = > IAS. Even though s(he) may be travelling at 150Kts IAS which is well below the indicated Vne of 180 kts (made that up too) the TAS is 210 Kts which is > Vne by 30kts !
Gliders are different animals obviously as they don't have an engine to deliver less power at alt, which is why the obviously have Vne tables.