Westland Wyvern canopy types and type conversions

[Max89]

I'm looking into the Wyvern S4 (previous designation was TF4), and it appears that some S4 aircraft have a solid rear canopy whereas others have a clear rear section.

Clear rear canopy: https://i.pinimg.com/736x/c7/1c/39/...7f4b054d--military-aircraft-military-jets.jpg
Solid rear canopy: http://www.airteamimages.com/pics/99/99187_big.jpg

Was the solid rear canopy the latest version? If so, was it a field modification or were those aircraft fitted with that style of canopy right in the factory?

Lastly, I've read that some S4 aircraft were actually converted from the S2 variant. Does anyone have the serial number ranges for the converted ones?

Edited October 9, 2017 by Max89

[71chally]

The canopy with the solid rear part was the later version, and was introduced due to structural issues with the all clear canopy, c1954/55.

 

Also worth noting that the windscreen changed as well, the flat armoured front screen originally had a curved outer screen fitted over it but this was later removed.  In the process this changed the windscreen assembly to canopy shape with the earlier type having a distinctive curved top when viewed from the front.

 

 

Edited October 9, 2017 by 71chally

[71chally]

According to the 4+ Wyvern book, TF.2s converted to TF.4/S.4 standard were VW868, 870, 871, 873 and VW880-886

[Max89]

I see. So all Wyverns manufactured after the new canopy's introduction were fitted with it from the factory, correct? Or were they all field modifications?

Edited October 9, 2017 by Max89

[71chally]

I believe that the canopy change was a service mod across the existing Wyvern fleet.

However some Wyverns were built and delivered as late as spring 1956, maybe they would have had the later canopy incorporated on the line.

[Max89]

So apart from the canopy and windshield, are you aware of any other modifications or externally visible differences between early S4s and later S4s?

[fatalbert]

The later versions deleted the tip fold on the wings.

[71chally]

As Fatalbert says the wingtip fold was deleted on production aircraft from a certain serial number on (will have to consult the book).

There were other very minor changes, such as an extra scoop for aircraft fitted with the 2nd generator, minor aerial changes, and the ability to carry a centreline tank.

[Seahawk]

2 hours ago, 71chally said:

As Fatalbert says the wingtip fold was deleted on production aircraft from a certain serial number on (will have to consult the book).

"Disabled on aircraft subsequent to VZ791" according to 4-Plus.

Edited October 10, 2017 by Seahawk

[Max89]

Did the wing look the same after the wingtip fold delete?

5 hours ago, 71chally said:

As Fatalbert says the wingtip fold was deleted on production aircraft from a certain serial number on (will have to consult the book).

There were other very minor changes, such as an extra scoop for aircraft fitted with the 2nd generator, minor aerial changes, and the ability to carry a centreline tank.

Do you know where the extra scoop was located? Any pictures would be helpful!

Edited October 10, 2017 by Max89

[Seahawk]

2 hours ago, Max89 said:

Did the wing look the same after the wingtip fold delete

Since the precise wording is "deactivated", Im assuming the answer is "yes".  No differences apparent in the drawings.

[huvut76g7gbbui7]

5 hours ago, Max89 said:

Do you know where the extra scoop was located? Any pictures would be helpful!

Best to choose an aircraft and build on that as scoops and vents positions differed even on aircraft in the same batch (sorry I can't remember which one of the books I read that in)

Note also that the engine cowling was cut back in later production batch.

Early canopy and no finlets on tailplane

Later canopy and cut back cowling

[huvut76g7gbbui7]

Forgot to add this one.

Cut back cowling but still with early canopy

You can clearly see the curved windscreen which 71chally points out in his post above.

[Max89]

Thanks guys. I would never have found all this info if I hadn't asked here.

 

I stumbled upon this photo (below) of a Wyvern that crash landed on the HMS Ark Royal in 1957. What is the thing circled in red? Also, am I looking in the wrong place or does this plane lack the four Hispano cannons?

 

Edited October 11, 2017 by Max89

[71chally]

13 hours ago, Scimitar said:

Best to choose an aircraft and build on that as scoops and vents positions differed even on aircraft in the same batch (sorry I can't remember which one of the books I read that in)

Note also that the engine cowling was cut back in later production batch.

The first picture (VW867) is a TF.2, all production, and the TF.2s converted to S.4s had the cut back cowling which was a feature of the later Python engine.

The second shot (VZ748) is a production S.4 with the the modified canopy, I think this may have been the test acft for that canopy.

The third shot is (VZ750 Farnborough 1952) which is a production S.4 with the early canopy and before the finlets were added.

8 hours ago, Max89 said:

I stumbled upon this photo (below) of a Wyvern that crash landed on the HMS Ark Royal in 1957. What is the thing circled in red? Also, am I looking in the wrong place or does this plane lack the four Hispano cannons?

Wyverns could be fitted with a cylindrical aerial (canon ranging?) in the port outer canon position, so it may be that.  I would say that the other three canon fairing covers are fitted.

The later addition double generator scoop also shows in that shot, it's the one that is a few feet ahead of the windscreen, port side.  The one adjacent to windscreen was the existing one.

 

 

[Seahawk]

11 hours ago, Max89 said:

What is the thing circled in red?

Aerial for AS-68/APG-5 radar rangefinder.

[71chally]

Just found this, a really good single source page on the Wyvern, has some of the 4+ book uploaded to it,

http://mikro-mir.at.ua/publ/5-1-0-20

[Max89]

5 hours ago, 71chally said:

The first picture (VW867) is a TF.2, all production, and the TF.2s converted to S.4s had the cut back cowling which was a feature of the later Python engine.

The second shot (VZ748) is a production S.4 with the the modified canopy, I think this may have been the test acft for that canopy.

The third shot is (VZ750 Farnborough 1952) which is a production S.4 with the early canopy and before the finlets were added.

Wyverns could be fitted with a cylindrical aerial (canon ranging?) in the port outer canon position, so it may be that.  I would say that the other three canon fairing covers are fitted.

The later addition double generator scoop also shows in that shot, it's the one that is a few feet ahead of the windscreen, port side.  The one adjacent to windscreen was the existing one.

 

 

I don't understand what you mean by cannon fairing covers. Are the cannons covered up, disabled or deleted? I hope that's not the case, because every Wyvern kit I've seen so far has cannons.

Edited October 11, 2017 by Max89

[71chally]

The cannon ports have pointed/conical fairings over them, you can see them clearly in the shot that you posted.

I think they just covered the cannon ports until they were fired.

Edited October 11, 2017 by 71chally

[Max89]

Ah, I see them now. I guess that photo of WP346 is what I'll model after.

Edited October 12, 2017 by Max89

[Max89]

BTW just out of curiosity, why is that blue stripe on top of WP346's fuselage not aligned with the stripe on its nose? This is different than what I see in the other photos.

[71chally]

It looks like WP346 was fitted with a replacement engine and cowling (as a complete ECU - engine change unit) from an aircraft with the higher camouflage demarkation.

Originally the EDSG  top surface only extended a little way down the fuselage side, later it was extended much further down the sides.

 

As for the cannons, I really don't know if they were readily removable or not, my guess is that they could be to save weight, maybe for when the airfcraft was configured for torpedo strike etc.  But I really don't know.

 

[huvut76g7gbbui7]

On 10/10/2017 at 7:32 PM, Scimitar said:

scoops and vents positions differed even on aircraft in the same batch (sorry I can't remember which one of the books I read that in)

It was in Wyvern from the cockpit which I have just scanned through.(tough job eh!)

There is no mention of the cannons being removed.

On 11/10/2017 at 11:53 AM, Seahawk said:

Aerial for AS-68/APG-5 radar rangefinder.

Surprisingly few pictures of this fitted but it appears to be where the port outer cannon would be.

If this is correct was the kit fitted in the cannon bay or was it small enough to fit inside the fairing?

[Max89]

I finally got the 4+ book.

 

I stumbled across a photo of a group of Wyverns, and I can't tell whether the first one in line (VZ763) has a dihedral tailplane. Did all S4 aircraft have the dihredral, or were there some that didn't?

 

[stevehnz]

Looking at that photo, I reckon its just a question of camera angle to the near aircraft, it is showing a lot more upper wing than the others which has the effect of making the tail plane dihedral look shallower, IMHO.

Steve.