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Why does this Jet Provost strikemaster have a textured leading edge?

What is a vortex generator?Why should isobars be aligned with the leading edge of the main wing for a transonic cruiser?What does the zig-zag pattern on Hawker Hunter's leading edge represent?What is the difference between a leading edge flap and a slat?Are STOL kits that use leading edge slats available for 'typical' GA aircraft?How does leading edge flap increase camber?Is c.g rear or fore of wing leading edge?Why does a sharp leading edge result in a larger pressure peak?Why does the F-15 have a swept-back trailing edge at its wing tips?Do leading edge flaps increase the critical angle of attack?

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11

$begingroup$

I was at Duxford recently, and spotted a Jet Provost Strikemaster that had a rough texture applied to a portion of the leading edge of the wing.

Does anyone know why this was applied?

aircraft-design aerodynamics military wing

share|improve this question

edited 2 days ago

Sam

asked 2 days ago

SamSam

15855 bronze badges

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$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Looks like part of the leading edge is missing and someone put in a rough patch awaiting the proper part, this is definitely not normal for any Strikemasters, and not for the Mk.80/80A in particular that were used by the Saudi air force.
  $endgroup$
  – jwenting
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  My guess: cheap attempt at a vortex generator. See answers to this question for the purpose.
  $endgroup$
  – DeltaLima
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @DeltaLima: Almost - it's artificial roughness to trip a laminar boundary layer.
  $endgroup$
  – Peter Kämpf
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Have you considered emailing Duxford to ask them? They'll likely know a lot about their planes.
  $endgroup$
  – David Richerby
  yesterday
  

  
  
  
  

add a comment | 

11

$begingroup$

I was at Duxford recently, and spotted a Jet Provost Strikemaster that had a rough texture applied to a portion of the leading edge of the wing.

Does anyone know why this was applied?

aircraft-design aerodynamics military wing

share|improve this question

edited 2 days ago

Sam

asked 2 days ago

SamSam

15855 bronze badges

New contributor

Sam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Looks like part of the leading edge is missing and someone put in a rough patch awaiting the proper part, this is definitely not normal for any Strikemasters, and not for the Mk.80/80A in particular that were used by the Saudi air force.
  $endgroup$
  – jwenting
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  My guess: cheap attempt at a vortex generator. See answers to this question for the purpose.
  $endgroup$
  – DeltaLima
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @DeltaLima: Almost - it's artificial roughness to trip a laminar boundary layer.
  $endgroup$
  – Peter Kämpf
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Have you considered emailing Duxford to ask them? They'll likely know a lot about their planes.
  $endgroup$
  – David Richerby
  yesterday
  

  
  
  
  

add a comment | 

$begingroup$

I was at Duxford recently, and spotted a Jet Provost Strikemaster that had a rough texture applied to a portion of the leading edge of the wing.

Does anyone know why this was applied?

aircraft-design aerodynamics military wing

share|improve this question

edited 2 days ago

Sam

asked 2 days ago

SamSam

15855 bronze badges

New contributor

Sam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

$endgroup$

share|improve this question

edited 2 days ago

Sam

asked 2 days ago

SamSam

15855 bronze badges

New contributor

Sam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

share|improve this question

edited 2 days ago

Sam

asked 2 days ago

SamSam

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New contributor

Sam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

asked 2 days ago

SamSam

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New contributor

Sam is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

asked 2 days ago

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2 Answers
2

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9

$begingroup$

The leading edges are roughened to improve the stall characteristics. Typically vortex generators are used for this purpose nowadays.

The 5 and the 5a were used by the RAF for pilot training and the nose strakes were fitted to improve the spinning characteristics - the leading edges of the wings had a roughened paint finish to improve the stall characteristics. The 5s with the tip tanks (I'm not sure if 5b is an official or 'unofficial' designation) were used by the RAF for nav training and didn't have the nose strakes (not sure about the roughened wing leading edges) I don't know if it was because the tip tanks themselves improved spin handling or if it was because they weren't flown by studes for spin training.

(source: User "Fritag" at www.britmodeller.com)

The rough grey coating on the wing of the aircraft was applied in order to break up the smooth airflow and give an early indication of the onset of a stall as the T5's original clean wing design gave the pilot little prior warning.

source: all-aero.com / RAF Museum

share|improve this answer

edited 2 days ago

answered 2 days ago

DeltaLimaDeltaLima

57.4k66 gold badges176176 silver badges258258 bronze badges

$endgroup$

• 
  
  
  

  
  3
  

  
  
  
  
  
  

  
  $begingroup$
  Not sure you should use dudes posting on an aeromodeler forum as source data. Just sayin'...
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @JohnK If you prefer PPrune, you can find similar quotes over there.
  $endgroup$
  – DeltaLima
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Still just anonymous people (like here) who may or may not know what they are talking about. You don't know they really are or what they know, or who wrote the All Aero bit. I've searched numerous pics of Mark 5a's and can't find any with that crazy leading edge treatment and can't find any OFFICIAL accounts that describe it, so I will default to skepticism, and my own knowledge of how dangerous that kind of LE contamination is. If that kind of surface treatment, equivalent to a heavy coating or rime ice, improves aileron effectiveness, well, there's a whole new paradigm.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @JohnK I don't think it is increasing the aileron effectiveness, instead it increases the turbulence over the aileron close to stall. This gives an early indication of impeding stall, which is more friendly than the laminar flow suddenly stalling, especially in a training aircraft.
  $endgroup$
  – DeltaLima
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  No that kind of roughness will simply cause a full separation and complete loss of aileron control at an angle prior to the normal stall AOA. I could be wrong in all this, but I want to see an authoritative source because this is pretty bizarre, and like I said, all the pics of Provosts I can find all show normal clean LEs.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  

 | 
show 1 more comment

5

$begingroup$

It's a "simulated ice shape" to simulate a heavy coating of rime ice. This aircraft was likely used in testing to explore the stall behaviour of the outboard wing forward of the aileron in icing conditions.

That surface texture would, believe me, NOT improve the stall behaviour. It will not generate vortices or favourable turbulence. It will drop the stalling AOA of the wing by a third, with a nasty leading edge first separation.

Lots of jets have taken off with way less surface roughness than that, and crashed. Morning frost is sufficient in many cases. It would be quite dangerous to fly. If it was flown like that, it was flown by a very experienced experimental test pilot. Or, it was tested in a full size wind tunnel. You sure wouldn't get me up in it.

That museum probably received the airplane from a test establishment when they were done with it, and just painted it and dressed it up without bothering to remove the LE treatment.

If anyone can find a picture of a regular, flying, in-service Provost with that surface treatment, I'll remove my post.

share|improve this answer

edited 2 days ago

answered 2 days ago

John KJohn K

38k11 gold badge6767 silver badges125125 bronze badges

$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  I agree with this not improving stall speed, but it only trips the boundary layer early. This by itself would not reduce stall AoA by a third. Icing will build up, leading to a spike protruding from the leading edge. This is more like the bugs on glider wings.
  $endgroup$
  – Peter Kämpf
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  On the CRJ program extensive testing was done with surface roughness models on the CRJ200 leading edge, and surface textures rougher than about 80 grit sandpaper would generate LE stall at about 9 degrees AOA vs normal at about 14. Several CRJs and Challengers (and numerous other hard LE airplanes) have crashed with just frost roughness. People have crashed 172s from taking off with frost on the wings because of the reduction in stall AOA and elimination of any warning.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Anyway, why on god's green earth would you want to trip the boundary layer prematurely in front of the aileron, vs at the root. This whole thing is very weird.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Agreed. But sometimes boundary layer effects are weird. This was certainly not designed from the outset but added later as a fix which seems to have worked. Premature stall hints to a sensitive airfoil – here the airfoil was more forgiving. I cannot imagine that a fix which reduces stall AoA on the outer wing by a third would be acceptable to anyone.
  $endgroup$
  – Peter Kämpf
  yesterday
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Not a dream :-) : re " ... Lots of jets ... and crashed. ... Morning frost is sufficient in many cases. ..." -> I've had many tens of internal Chinese passenger flights. Elsewhere too but mainly China. I stand at the end of the airbridge by the windows and look along the aircraft. I note the snow/slush cover on the ground, and vehicle and aircraft taxiing tracks. I wonder if I'd ever see the ice buildup that they missed or didn't care enough about. I never do. All always looks OK enough. I enter the aircraft. Nothing bad ever happens. I wonder what I'd do if I saw enough to worry me.
  $endgroup$
  – Russell McMahon
  yesterday
  

  
  
  
  

 | 
show 3 more comments

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9

$begingroup$

The leading edges are roughened to improve the stall characteristics. Typically vortex generators are used for this purpose nowadays.

The 5 and the 5a were used by the RAF for pilot training and the nose strakes were fitted to improve the spinning characteristics - the leading edges of the wings had a roughened paint finish to improve the stall characteristics. The 5s with the tip tanks (I'm not sure if 5b is an official or 'unofficial' designation) were used by the RAF for nav training and didn't have the nose strakes (not sure about the roughened wing leading edges) I don't know if it was because the tip tanks themselves improved spin handling or if it was because they weren't flown by studes for spin training.

(source: User "Fritag" at www.britmodeller.com)

The rough grey coating on the wing of the aircraft was applied in order to break up the smooth airflow and give an early indication of the onset of a stall as the T5's original clean wing design gave the pilot little prior warning.

source: all-aero.com / RAF Museum

share|improve this answer

edited 2 days ago

answered 2 days ago

DeltaLimaDeltaLima

57.4k66 gold badges176176 silver badges258258 bronze badges

$endgroup$

• 
  
  
  

  
  3
  

  
  
  
  
  
  

  
  $begingroup$
  Not sure you should use dudes posting on an aeromodeler forum as source data. Just sayin'...
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @JohnK If you prefer PPrune, you can find similar quotes over there.
  $endgroup$
  – DeltaLima
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Still just anonymous people (like here) who may or may not know what they are talking about. You don't know they really are or what they know, or who wrote the All Aero bit. I've searched numerous pics of Mark 5a's and can't find any with that crazy leading edge treatment and can't find any OFFICIAL accounts that describe it, so I will default to skepticism, and my own knowledge of how dangerous that kind of LE contamination is. If that kind of surface treatment, equivalent to a heavy coating or rime ice, improves aileron effectiveness, well, there's a whole new paradigm.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @JohnK I don't think it is increasing the aileron effectiveness, instead it increases the turbulence over the aileron close to stall. This gives an early indication of impeding stall, which is more friendly than the laminar flow suddenly stalling, especially in a training aircraft.
  $endgroup$
  – DeltaLima
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  No that kind of roughness will simply cause a full separation and complete loss of aileron control at an angle prior to the normal stall AOA. I could be wrong in all this, but I want to see an authoritative source because this is pretty bizarre, and like I said, all the pics of Provosts I can find all show normal clean LEs.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  

 | 
show 1 more comment

9

$begingroup$

The leading edges are roughened to improve the stall characteristics. Typically vortex generators are used for this purpose nowadays.

The 5 and the 5a were used by the RAF for pilot training and the nose strakes were fitted to improve the spinning characteristics - the leading edges of the wings had a roughened paint finish to improve the stall characteristics. The 5s with the tip tanks (I'm not sure if 5b is an official or 'unofficial' designation) were used by the RAF for nav training and didn't have the nose strakes (not sure about the roughened wing leading edges) I don't know if it was because the tip tanks themselves improved spin handling or if it was because they weren't flown by studes for spin training.

(source: User "Fritag" at www.britmodeller.com)

The rough grey coating on the wing of the aircraft was applied in order to break up the smooth airflow and give an early indication of the onset of a stall as the T5's original clean wing design gave the pilot little prior warning.

source: all-aero.com / RAF Museum

share|improve this answer

edited 2 days ago

answered 2 days ago

DeltaLimaDeltaLima

57.4k66 gold badges176176 silver badges258258 bronze badges

$endgroup$

• 
  
  
  

  
  3
  

  
  
  
  
  
  

  
  $begingroup$
  Not sure you should use dudes posting on an aeromodeler forum as source data. Just sayin'...
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @JohnK If you prefer PPrune, you can find similar quotes over there.
  $endgroup$
  – DeltaLima
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Still just anonymous people (like here) who may or may not know what they are talking about. You don't know they really are or what they know, or who wrote the All Aero bit. I've searched numerous pics of Mark 5a's and can't find any with that crazy leading edge treatment and can't find any OFFICIAL accounts that describe it, so I will default to skepticism, and my own knowledge of how dangerous that kind of LE contamination is. If that kind of surface treatment, equivalent to a heavy coating or rime ice, improves aileron effectiveness, well, there's a whole new paradigm.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @JohnK I don't think it is increasing the aileron effectiveness, instead it increases the turbulence over the aileron close to stall. This gives an early indication of impeding stall, which is more friendly than the laminar flow suddenly stalling, especially in a training aircraft.
  $endgroup$
  – DeltaLima
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  No that kind of roughness will simply cause a full separation and complete loss of aileron control at an angle prior to the normal stall AOA. I could be wrong in all this, but I want to see an authoritative source because this is pretty bizarre, and like I said, all the pics of Provosts I can find all show normal clean LEs.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  

 | 
show 1 more comment

$begingroup$

The leading edges are roughened to improve the stall characteristics. Typically vortex generators are used for this purpose nowadays.

The 5 and the 5a were used by the RAF for pilot training and the nose strakes were fitted to improve the spinning characteristics - the leading edges of the wings had a roughened paint finish to improve the stall characteristics. The 5s with the tip tanks (I'm not sure if 5b is an official or 'unofficial' designation) were used by the RAF for nav training and didn't have the nose strakes (not sure about the roughened wing leading edges) I don't know if it was because the tip tanks themselves improved spin handling or if it was because they weren't flown by studes for spin training.

(source: User "Fritag" at www.britmodeller.com)

The rough grey coating on the wing of the aircraft was applied in order to break up the smooth airflow and give an early indication of the onset of a stall as the T5's original clean wing design gave the pilot little prior warning.

source: all-aero.com / RAF Museum

share|improve this answer

edited 2 days ago

answered 2 days ago

DeltaLimaDeltaLima

57.4k66 gold badges176176 silver badges258258 bronze badges

$endgroup$

share|improve this answer

edited 2 days ago

answered 2 days ago

DeltaLimaDeltaLima

57.4k66 gold badges176176 silver badges258258 bronze badges

answered 2 days ago

DeltaLimaDeltaLima

57.4k66 gold badges176176 silver badges258258 bronze badges

answered 2 days ago

DeltaLimaDeltaLima

57.4k66 gold badges176176 silver badges258258 bronze badges

5

$begingroup$

It's a "simulated ice shape" to simulate a heavy coating of rime ice. This aircraft was likely used in testing to explore the stall behaviour of the outboard wing forward of the aileron in icing conditions.

That surface texture would, believe me, NOT improve the stall behaviour. It will not generate vortices or favourable turbulence. It will drop the stalling AOA of the wing by a third, with a nasty leading edge first separation.

Lots of jets have taken off with way less surface roughness than that, and crashed. Morning frost is sufficient in many cases. It would be quite dangerous to fly. If it was flown like that, it was flown by a very experienced experimental test pilot. Or, it was tested in a full size wind tunnel. You sure wouldn't get me up in it.

That museum probably received the airplane from a test establishment when they were done with it, and just painted it and dressed it up without bothering to remove the LE treatment.

If anyone can find a picture of a regular, flying, in-service Provost with that surface treatment, I'll remove my post.

share|improve this answer

edited 2 days ago

answered 2 days ago

John KJohn K

38k11 gold badge6767 silver badges125125 bronze badges

$endgroup$

• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  I agree with this not improving stall speed, but it only trips the boundary layer early. This by itself would not reduce stall AoA by a third. Icing will build up, leading to a spike protruding from the leading edge. This is more like the bugs on glider wings.
  $endgroup$
  – Peter Kämpf
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  On the CRJ program extensive testing was done with surface roughness models on the CRJ200 leading edge, and surface textures rougher than about 80 grit sandpaper would generate LE stall at about 9 degrees AOA vs normal at about 14. Several CRJs and Challengers (and numerous other hard LE airplanes) have crashed with just frost roughness. People have crashed 172s from taking off with frost on the wings because of the reduction in stall AOA and elimination of any warning.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Anyway, why on god's green earth would you want to trip the boundary layer prematurely in front of the aileron, vs at the root. This whole thing is very weird.
  $endgroup$
  – John K
  2 days ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Agreed. But sometimes boundary layer effects are weird. This was certainly not designed from the outset but added later as a fix which seems to have worked. Premature stall hints to a sensitive airfoil – here the airfoil was more forgiving. I cannot imagine that a fix which reduces stall AoA on the outer wing by a third would be acceptable to anyone.
  $endgroup$
  – Peter Kämpf
  yesterday
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Not a dream :-) : re " ... Lots of jets ... and crashed. ... Morning frost is sufficient in many cases. ..." -> I've had many tens of internal Chinese passenger flights. Elsewhere too but mainly China. I stand at the end of the airbridge by the windows and look along the aircraft. I note the snow/slush cover on the ground, and vehicle and aircraft taxiing tracks. I wonder if I'd ever see the ice buildup that they missed or didn't care enough about. I never do. All always looks OK enough. I enter the aircraft. Nothing bad ever happens. I wonder what I'd do if I saw enough to worry me.
  $endgroup$
  – Russell McMahon
  yesterday
  

  
  
  
  

 | 
show 3 more comments

5

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It's a "simulated ice shape" to simulate a heavy coating of rime ice. This aircraft was likely used in testing to explore the stall behaviour of the outboard wing forward of the aileron in icing conditions.

That surface texture would, believe me, NOT improve the stall behaviour. It will not generate vortices or favourable turbulence. It will drop the stalling AOA of the wing by a third, with a nasty leading edge first separation.

Lots of jets have taken off with way less surface roughness than that, and crashed. Morning frost is sufficient in many cases. It would be quite dangerous to fly. If it was flown like that, it was flown by a very experienced experimental test pilot. Or, it was tested in a full size wind tunnel. You sure wouldn't get me up in it.

That museum probably received the airplane from a test establishment when they were done with it, and just painted it and dressed it up without bothering to remove the LE treatment.

If anyone can find a picture of a regular, flying, in-service Provost with that surface treatment, I'll remove my post.

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edited 2 days ago

answered 2 days ago

John KJohn K

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  I agree with this not improving stall speed, but it only trips the boundary layer early. This by itself would not reduce stall AoA by a third. Icing will build up, leading to a spike protruding from the leading edge. This is more like the bugs on glider wings.
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  – Peter Kämpf
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  On the CRJ program extensive testing was done with surface roughness models on the CRJ200 leading edge, and surface textures rougher than about 80 grit sandpaper would generate LE stall at about 9 degrees AOA vs normal at about 14. Several CRJs and Challengers (and numerous other hard LE airplanes) have crashed with just frost roughness. People have crashed 172s from taking off with frost on the wings because of the reduction in stall AOA and elimination of any warning.
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  – John K
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  Anyway, why on god's green earth would you want to trip the boundary layer prematurely in front of the aileron, vs at the root. This whole thing is very weird.
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  – John K
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  Agreed. But sometimes boundary layer effects are weird. This was certainly not designed from the outset but added later as a fix which seems to have worked. Premature stall hints to a sensitive airfoil – here the airfoil was more forgiving. I cannot imagine that a fix which reduces stall AoA on the outer wing by a third would be acceptable to anyone.
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  – Peter Kämpf
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  Not a dream :-) : re " ... Lots of jets ... and crashed. ... Morning frost is sufficient in many cases. ..." -> I've had many tens of internal Chinese passenger flights. Elsewhere too but mainly China. I stand at the end of the airbridge by the windows and look along the aircraft. I note the snow/slush cover on the ground, and vehicle and aircraft taxiing tracks. I wonder if I'd ever see the ice buildup that they missed or didn't care enough about. I never do. All always looks OK enough. I enter the aircraft. Nothing bad ever happens. I wonder what I'd do if I saw enough to worry me.
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  – Russell McMahon
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It's a "simulated ice shape" to simulate a heavy coating of rime ice. This aircraft was likely used in testing to explore the stall behaviour of the outboard wing forward of the aileron in icing conditions.

That surface texture would, believe me, NOT improve the stall behaviour. It will not generate vortices or favourable turbulence. It will drop the stalling AOA of the wing by a third, with a nasty leading edge first separation.

Lots of jets have taken off with way less surface roughness than that, and crashed. Morning frost is sufficient in many cases. It would be quite dangerous to fly. If it was flown like that, it was flown by a very experienced experimental test pilot. Or, it was tested in a full size wind tunnel. You sure wouldn't get me up in it.

That museum probably received the airplane from a test establishment when they were done with it, and just painted it and dressed it up without bothering to remove the LE treatment.

If anyone can find a picture of a regular, flying, in-service Provost with that surface treatment, I'll remove my post.

share|improve this answer

edited 2 days ago

answered 2 days ago

John KJohn K

38k11 gold badge6767 silver badges125125 bronze badges

$endgroup$

share|improve this answer

edited 2 days ago

answered 2 days ago

John KJohn K

38k11 gold badge6767 silver badges125125 bronze badges

answered 2 days ago

John KJohn K

38k11 gold badge6767 silver badges125125 bronze badges

answered 2 days ago

John KJohn K

38k11 gold badge6767 silver badges125125 bronze badges