Spitfire Mk V wing strakes

[Brian J]

I have kits of both the Airfix Mk Vb (with wing strakes) and the recently released Eduard Mk Vb/Vc 'Eagle's Call' kit which provides wings for both versions neither of which has the wing strakes.  I realize that the Mk Vc had a strengthened wing.  On page 32 of the Wingleader Supermarine Spitfire Mk V in Europe and North Africa it states, "To temporarily solve the problem, bracing strips were applied internally from February 1941 before more robust external strips were introduced in July 1942.  These strips were retro-fitted to as many Mk I, Mk II and Mk Va and Vbs as possible.  There are not many photos of Spitfire Mk Vbs that show the upper wing surface. 

 

The photos I have seen usually do not have this external bracing/strakes.  Is there any rule of thumb or a way of making an educated guess as to which unit, time period or theatre would indicate when a Spitfire Mk V would have this wing bracing?  I have the complete let of Watermark decals which provides several markings for Canadian Mk V squadrons.  I would think that W/C John A. Kent's J*AK in June of 1941 would not have had the strakes while S/L Geoffrey Northcott's Mk V in November 1943 would have them (this aircraft has been restored and flying in Duxford, England, several photos of which can be found in Spitfires and Polished Metal:  Restoring the Classic Fighter.    

[Troy Smith]

1 hour ago, Brian J said:

Is there any rule of thumb or a way of making an educated guess as to which unit, time period or theatre would indicate when a Spitfire Mk V would have this wing bracing? 

 

"

  

On 10/10/2015 at 10:39, Edgar said:

The stiffeners were fitted, to the Va & Vb, from 16-7-42. Any Mk.I & 2 aircraft, in training units, which needed a damaged wing to be replaced, usually had the Mk.V versions fitted.

The Vc also had strengthening fitted, but it was normally internal to the wells, and was fitted from 14-8-42

 

The late Edgar Brooks, noted Spitfire researcher.

 

HTH

 

[Brian J]

I apologize if I appear to be beating the subject into the ground but I'd like to make a further comment.  I went to the Troy Smith post (above) and read the eight earlier posts that somewhat clarified my question.  The one by Graham Boak struck a chord..."Strictly, there (sic) were added during the war and can be seen on (usually) LF MkVB aircraft still in service in 1944."  

 

His observation may explain why AE*A EP120  which has clipped wings and is still flying has the strakes and most likely the other Canadian Mk Vbs on the Watermark decal sheets with clipped wings would have strakes.  While thumbing through my copy of the Wingleader Number 6, Supermarine Spitfire Mk V I noticed the following:  

-page 49, "A clipped wing Mk Vb, EP644, RY-S photographed at Church Stanton in May 1943" no strakes.

-page 50.  "Port and starboard views of a No 349 Sqn Spitfir Mk Vb, GE-U...which was the second Belgian squadron in the RAF, received Mk Vbs in September 1943..."  Again, no strakes.

-page 51.  "From March 1st to 12th, 1943, the largest operational exercise ever carried out in Britain...421 (Canadian) Squadron's Spitfire Mk Vbs were part of the Eastland force..."  Again, no strakes.

-page 58.  "...and Mk Vb, ER220, QJ-R...porbabaly photographed at Ben Gardane, Tunisia, in March 1943."  Again, no strakes.       

 

My point is at what point in time were strakes retro-fitted to Mk Vbs at the unit level or where ever.  Much like Battle of Britain Mk Is didn't all receive Sky camouflage at the same time I think it may have taken several months, or more for operational Mk Vbs to be retro-fitted with strakes. 

With so few photos that show upper wing surfaces it is difficult to know if the subject we are modelling has strakes.  Phew...thanks for reading!  Any clarifications?    

[Hornet133]

It was a standard fitting to the LF Mk.Vb (the ones described as 'Clipped, Clapped, Cropped' in certain literature) which spent their time on low level missions getting a lot of buffeting in the thicker air at low level, to strengthen the wing.  Standard Mk.Vbs did not usually have them unless the wing had a weak point caused by an accident.

 

The strakes were fitted at M.U level, not on the operational Sqns. Other parts of the conversion to LF Mk.Vb standard included clipped wings and six stack exhausts (same as the Mk.IX). There were six Sqns (in two Wings) flying these LF Mk.Vbs at the time of the D-Day invasion in which they were heavily involved.

 

If you ask why bother, well the LF Mk.Vb was 30 MPH faster than the Mk.IX at Sea Level...

[gingerbob]

The other missing (?) factor is that at some point an internal strengthening mod was incorporated (on the production line?), making the strakes unnecessary on these aircraft.  Castle Bromwich was building Vbs far longer than Supermarine, so it is likely that relatively late production examples would not have been given the strake mod.

 

I can't tell you any serial number range, because frankly I don't have a clear picture of this one.  But that's the concept, as far as I've deduced so far.

[JRS-AU]

Tamiya have documented "form" for basing their designs on modern restorations (USAF Museum FW 190D-9 with the wing restoration is another example).  Perhaps their straked wing versions are based on modern restorations rather than period research?

[gingerbob]

No, there's plenty of evidence that it isn't just a "patched up airplane fluke".