P40 Australian War Memorial

[planecrazy]

Australian War Memorials’s A29-133.








Bit of close up detail.








I knew they covered the guns to stop dirt getting in but didn’t realise they
covered the spent case chutes on the underside of the wings as well!

[suthg]

I believe they covered the gun ports to stop icing up and subsequent jamming of the equipment. I can't understand the need for cartridge ejection ports to be covered unless there was a risk of bird invasion!

[planecrazy]

Would it be to stop mud and dirt filling the chutes and eliminate blocking the spent cases getting out?

[harvard1041]

Believe the tape was made by Minnesota Mining & Manufacturing ( yip - 3M ) ... bit of aerodynamic benefit to covering up all openings.

Interesting aircraft for sure - came from Nelson Wilson in Melbourne I think ( our Aussie friends will know the history ) ... and built up for the Museum....put a set of early exhausts on her, and would look great

Cheers
Hvd1041

[davidd]

I can understand why it might be beneficial to "streamline" a P-40 for a long ferry flight, but for operational flying ...?? Would it be a good thing to have spent (and very hot!) cartridge cases choking up inside the wing? Would that not threaten to jam the guns? Something would have to give, or were they relying on the hot casings igniting the fabric blocking their exit? Did the ejected cases slide down chutes or did they just spew out inside the wing and jump about? I would have thought the former, but a I am not totally familiar about the hardware. Can anybody help us out with pictures from the official TO book.
And I agree with John S - a set of early round-section exhaust stubs would be a worthy improvement, although originals are probably fairly hard to get these days, as most later P-40s (including majority of survivors) seem to have the "fish tails" fitted.
David D

[planecrazy]

Here's a good video of one of the local ones, blanks but as you can see they come out at a rate.

[harvard1041]

Hi David

Yes - blast tubes taped up for operational flying wouldn't present any problem - don't believe the link & case chutes were taped up however - or simply cut prior to taxi out if previously taped up. Couple of photos here of the setup.

Hvd1041

[davidd]

John S,
Many thanks for the technical illustrations, it is pretty much as I imagined, and of course the open slots in the lower wing surface do indeed line up perfectly with the ejection chutes (why wouldn't they?) However the real eye opener is the velocity of the ejected shell cases, as can be seen in the previous video clip, and the amount of empty cases and clips after even a very short burst from (all six?) guns is astonishing to the uninitiated - just a cascade of hot metal bits bouncing off the concrete floor.
David D

[Dave Homewood]

Did you know Jim Sheddan was "shot down" by the ejecting shells of his CO's aircraft? He was in a Tempest and the shells were a little bigger I guess but they took out his radiator, his engine died and he crashed, badly. So those hot bits of brass can be as deadly as the slugs that came out of them.

I asked Bryan Cox what he could add to this conversation about the tape over the ejector ports. He wrote this:
"My only explanation is to either keep out insects such as bees and wasps - or birds ! The guns on the P-40’s extended out from the wingtips, whereas on the Corsairs they weren’t but remained internal, so when they weren’t ‘operational’ the orifices were normally taped over for the same reasons."

When he says Wingtips he means the leading edge.

[nuuumannn]

Here's a good video of one of the local ones, blanks but as you can see they come out at a rate.

Watched them doing this on the ground at Wanaka during the airshow. Very impressive to see close up as we were on the flight line at the time - Gold Pass Flight Line Walk. Rather laughingly, the airshow staff were hurriedly ushering us toward the nearest gate in front of the P-40, but the P-40 crew were telling everyone to stop and remain clear, so, sensibly we did, but the airshow staff were getting impatient - that is until the P-40's guns started firing.

[curtiss]

I have never seen any photographs of the link chutes taped up on operational aircraft - does anyone have anything? I am a bit suspicious that the chutes may have just been covered when aircraft were stored or guns removed. Stand to be corrected though.

[Dave Homewood]

Is this maybe tape over the ejector chutes? Hard to tell

[Dave Homewood]

And these ones

[curtiss]

Certainly looks like there is something there. Must be a technical instruction somewhere regarding the covering of gun muzzles, maybe the same instruction would refer to the chutes? I have looked through all my Curtiss P40 manuals and cant find anything, so perhaps the various Air Forces issued their own instructions.