Spitfire Underwing Gun Heating Vents

[fishplanebeer]

As most if not all 72nd scale kits of the Spitfire 1, such as the Airfix, Tamiya and KP, do not have them can anyone confirm when they were introduced (I'd always assumed before the BoB) and when and why they were eventually removed and/or became surplus to requirements? 

 

Apologies if this has been covered before but I couldn't find a related post.

 

Regards

Colin.

[gingerbob]

Yes, before BofB.  Somewhere I've got record of when removal happened, but I don't think (offhand) that it pertains to 'a' winged aircraft.

[Dave Swindell]

10 hours ago, fishplanebeer said:

when and why they were eventually removed

As far as I'm aware, once an aircraft had them fitted, they weren't removed.

The "a" wing didn't have them originally, they were added in early 1940 to improve flow of heating air to the outer guns. especially on the port wing where the hot air from the radiator under the stbd wing had much further to travel. This is why the venturi vent blister is larger on the port side than on the stbd side.

The vents were carried over to the "b" wing, with the same arrangement for the outboard machine guns and changes made inboard to heat the cannons instead of the removed machine guns.

With the introduction of the "c" wing with potentially 4 cannon to heat the supply from the radiator was insufficient to heat all guns, so the radiator ducting was used to heat the cannon and exhaust intensifier heating was introduced for the outboard machine guns, for which the venturi vents were not required and thus never fitted.

With the change to the two stage merlin with it's split radiator under each wing there was sufficient hot air from each radiator to service the cannon and machine guns in that wing, so the exhaust intensifier heating was no longer needed, nor were the venturi vents needed, again never fitted.

This later heating system was carried over to the "e" wing, so again no venturi vents required.

So unless you have evidence otherwise, the venturi vents should be on "b" wings, and "a" wings from early 1940 onwards.

[fishplanebeer]

I'd always assumed they should be there on the early marques so it's very good to know that for once my assumptions haven't been completely off the mark. However it's rather odd that all the Spitfire 1's in 72nd scale don't have them as I'd have thought at least one manufacturer would have got this detail right.

 

Regards

Colin.

[Dave Swindell]

8 minutes ago, fishplanebeer said:

I'd have thought at least one manufacturer would have got this detail right.

That rather depends on your point of view, it could be said that the plastic is right and the decals are wrong....

The plastic represents the wing before the introduction of the vents, so would be correct for any spitfire up to early 1940,

Granted it would be easier to file off moulded venturi vents to model an early version than adding them to represent a later version, but they're not that hard to do if you want to add them, and most people wouldn't notice their absence if you didn't bother. Your model, your choice 🙂

[fishplanebeer]

Unless these three manufacturers all used the same 'early' plans their omission is purely down to lack of attention to detail and/or poor research on their part.

 

Adding them is not a major issue, albeit a little tricky with my hands and eyesight, but some more recent kits have been criticised for far less, for example the new Arma P51's where there was great debate about some riveting on the inside of the u/c doors. There again at almost £20 a go perhaps expectations were somewhat higher which I can appreciate.

 

Regards

Colin.

[Dave Swindell]

13 hours ago, fishplanebeer said:

their omission is purely down to lack of attention to detail and/or poor research on their part.

That's rather harsh, Colin.

There were at least 300 Spitfires built with wings as kitted, and the Spitfire was in Squadron service for the best part of 18 months before the vents were introduced.

The kits aren't inaccurate, they just represent an earlier variant to that which you wish to model. 

[fishplanebeer]

My point is I don't think the manufacturers deliberately or knowingly made an early version, especially Airfix where all their decals are for BoB machines, it was them not paying attention to detail. The KP Vb doesn't have them either, at least not the version I have, so I still think it is down to a lack of understanding of the aircraft that they are modelling and a lack of attention to detail.

 

Regards

Colin.