Spitfire underwing vents

[Test Graham]

This question was raised a month or so back, my apologies if this is the wrong forum but I can't find the original postings, and most people look in here. There were two small outlets, one underneath each wing towards the tip. They are seen up to Mk.VB but not on later types.

Source The Secret Years, Tim Mason, Hikoki. Problems with inadequate heating of the guns led to the closure of these vents from mid-1942, as tested on Mk.Vb AA875. By the end of 1942 Mk.Vc BR351 was tested with redesigned hot air arrangements.

[TonyT]

This question was raised a month or so back, my apologies if this is the wrong forum but I can't find the original postings, and most people look in here. There were two small outlets, one underneath each wing towards the tip. They are seen up to Mk.VB but not on later types.

Source The Secret Years, Tim Mason, Hikoki. Problems with inadequate heating of the guns led to the closure of these vents from mid-1942, as tested on Mk.Vb AA875. By the end of 1942 Mk.Vc BR351 was tested with redesigned hot air arrangements.

Yep they blanked them off near the guns, have the drawings for it.

[TonyT]

Should be listed as mod 710, starting around 26-1-43.

Edgar

And i haven't forgot Edgar

[Test Graham]

But Mk.Vc were being delivered to Malta - I think without these vents - from mid-42, which makes me wonder a little about the date of that Mod. Perhaps someone can come up with pictures of early Mk.Vc with these vents.

We still haven't come up with a good explanation why they are different sizes port and starboard, although several sources state that one side's guns ran colder than the other. Perhaps one side's vent was smaller in an attempt to allow for this?

[Dave Fleming]

But Mk.Vc were being delivered to Malta - I think without these vents - from mid-42, which makes me wonder a little about the date of that Mod. Perhaps someone can come up with pictures of early Mk.Vc with these vents.

We still haven't come up with a good explanation why they are different sizes port and starboard, although several sources state that one side's guns ran colder than the other. Perhaps one side's vent was smaller in an attempt to allow for this?

Could it be related to one side having the oil cooler on it and the other the larger radiator?

[Test Graham]

I don't doubt the date as written, but the link to the design of the universal wing appears odd. A&AEE were testing these blanks in mid'42, which is long after the universal wing has been designed, built and delivered. Either Supermarine were at least 12 months ahead of the A&AEE on trials, which is a bit surprising, or early examples of the universal wing were built with these vents. I doubt the latter, but they were building these wings in late 1941. Waiting until January 1943 before introducing a mod to "catch up" with the earlier wing seems a long time.

Switching to Spitfire The History, we have Boscombe's recommendation for removal of these vents as being made in August 1942, which ties fairly well with the trials and the Jan 43 Mod 710. This is linked to the Mk.Vb only, so the universal wing did not have these vents. Supermarine had produced a solution to the gun heating problem in 1941, but everyone concerned was still faffing on with the earlier wing problem as if the other wing did not exist. Priorities, I guess: it just wasn't seen as too important. Nice to have but not significant.

A&AEE weren't over-impressed with the gun heating on the universal wing either, but that's another story.

So for modellers concerned about these vents, they are only on aircraft with the earlier wing up to early 1943. They are not on the universal wing, as noticed. Make sure they aren't on any of the later war LF Mk.VBs, either. Assuming the aircraft had Mod 710 embodied, of course. I wonder just how many models actually have these vents represented?

[Pascal]

Hi Graham,

It was me who posted this question (Aircraft Related Subjects => Real Aviation => Spitfire upper wing reinforcement strakes). Thanks a lot for your answers.

I wonder just how many models actually have these vents represented?

The Mk Vb from Hasegawa, scale 1/32, and the Mk Vb from Tamiya, scale 1/48 have these vents represented. The Hasegawa kit has decals for 3 versions : EP 689 Sicily 1943, AB 183, Spring 1942 and AB 326, May 1942. The Tamiya kit also has decals for 3 versions : EN 821, BL 479 and AGM (Wing Commander A.G. Malan), without any dates.

Greetings

Pascal

Edited February 3, 2009 by Pascal

[Troffa]

Ok, this is at least the second thread I have seen in which Edgar's posts seem to have disapeared- is this a deliberate action by Edgar or by one of the Mods?

Can anyone delete their own posts once posted?

Its just that these threads can be hard to follow if half the posts are missing.

Edit: Ok, I have just found the delete button on my posts- mystery solved.

Edited February 4, 2009 by Troffa