F4U belly window

[Dana Bell]

Hi mjfur,

Yes the brace (seen inside the artwork above) was eliminated at the same time as the window was replaced by the hatch (c/n 2531 = BuNo 50066); in the drawing in post 7 it's the "V" seen inside the window. Note that it could be removed from earlier aircraft that still had the window, even though there was no requirement to retrofit windows with hatches.

Cheers,



Dana

 

[Hoggardhigh]

View attachment 526825View attachment 526826

Where did you get those pictures?

 

[Hoggardhigh]

It would appear that later during F4U production, the ventral hatch introduced late in F4U-1A production was replaced with a simple metal panel. Anyone here know if that may be correct?

 

[mjfur]

From an original Corsair IV manual that I have. Kind of odd that the factory used "IV" on the cover but -4 on the inside.

 

[mjfur]

Hi Hoggardhigh,

Before I wrote my two small books on the early Corsairs I spent two years digging through the contract and BuAer correspondence files at the National Archives in College Park. CO was a major issue, and one of the reasons the flare pistol port was sealed beside the pilot's right hip and the reason the aft fuselage vents were added late in production. The Corsair had a number of issues that required minor fixes, most of which are visible in the photos once you know they're there. Unfortunately, I've never found the fix for fumes entering through the ventral cockpit hatch.

Cheers,


Dana

While there are various Group "A" MCR's that address fume proofing specific areas/frames (#129.5 #134, #218, etc.) there is also a Group "B" MCR-629 that indicates "General - Procedure for CO Fumeproofing of Cockpit" that may have included the hatch.

Regards,
Mike

 

[John10]

Hi all,

It is known that early F4U-1 Corsairs had a small window under the belly, which was deleted in the later F4U-1A and -1D models.

Does anyone have any specific details about this modification, i.e. the deletion of the window from F4U-1A/-1D production?

Thanks

The oval shaped belly windows were installed on the XF4U-1 Corsair Prototype with the intended purpose of aerial bombing of enemy bomber formations, in flight, not ground bombing. The XF4U-1 prototype also had 10 internal bomb compartments inside the outer wings, capable of holding 40, 5.2 pound anti aircraft bombs. The pilot would line up on the bomber formations from above, using the belly window and release the anti aircraft bomb payload. The bomb compartments were deleted on later prototypes, as it was deemed impractical, but for some reason, they kept the belly window through the F4U-1A's. At some point during the 1A Variants, that window was deleted. I'm sorry, I don't know exactly when that was.
Source: book, F4U Corsair. D&S VOL 55. By BERT KINZEY.

 

[Dana Bell]

There's been a lot of confusion over the use of a bombing window and "anti-aircraft bombs" in the XF4U-1 and subsequent. Navy doctrine had evolved to use fighters for suppression of anti-aircraft guns on enemy ships - after, of course, those same fighters had gunned down all the totally inadequate defending enemy fighters. Some time in the 1950s the drawings showing the XF4U-1s internal racks as anti-aircraft weapons were misinterpreted; they should have been called "anti-anti-aircraft" bombs instead. Once the story had been published it was almost impossible to correct the error.

The racks were changed to external wing mounts on production aircraft, then eliminated altogether before heavier bomb rack were mounted under the fuselage. The windows were replaced by access hatches on F4U-1A 50067 and FG-1A 13893. (I've not found a record of the change in Brewster production.)

The access hatch led to an increase in cockpit carbon monoxide, which took a little additional cleaning up. There are also stories that the bombing windows were overpainted on some aircraft, but I've seen no proof of this and it makes little sense.

Cheers,


Dana

 

[John10]

There's been a lot of confusion over the use of a bombing window and "anti-aircraft bombs" in the XF4U-1 and subsequent. Navy doctrine had evolved to use fighters for suppression of anti-aircraft guns on enemy ships - after, of course, those same fighters had gunned down all the totally inadequate defending enemy fighters. Some time in the 1950s the drawings showing the XF4U-1s internal racks as anti-aircraft weapons were misinterpreted; they should have been called "anti-anti-aircraft" bombs instead. Once the story had been published it was almost impossible to correct the error.

The racks were changed to external wing mounts on production aircraft, then eliminated altogether before heavier bomb rack were mounted under the fuselage. The windows were replaced by access hatches on F4U-1A 50067 and FG-1A 13893. (I've not found a record of the change in Brewster production.)

The access hatch led to an increase in cockpit carbon monoxide, which took a little additional cleaning up. There are also stories that the bombing windows were overpainted on some aircraft, but I've seen no proof of this and it makes little sense.

Cheers,


Dana

Dana,
Just so I'm clear, you are saying the small bombs were not used against bombers, but against anti aircraft guns on ships and that small window was used for that purpose?
Now I'm confused. I have been believing and retelling the bomber story for years, correcting people who were saying the belly window was for landing on carriers or reconnisence photography. Thank you Dana for clearing that up for me.
If I may, tap into your vast knowledge about Corsairs, I would like to ask you another question? Prior to the F4U-1P Corsairs, for reconnisence photography missions, about 60 converted F4U-1D's,
(which the 1D's were produced in April of 1944) what did they do for reconnisence? Did they remove one of the .50 cal guns and replace it with a camera inside the gun port? Thanks Dana and cheers!

 

[Dana Bell]

Hi John,

Yes, we all were confused - it's just a story that won't die. The belly window was a bombing window, but for setting up attacks on enemy ship AAA. (One version of the window story had the window used to check if the landing gear was down, even though the landing gear couldn't be seen through the window.)

The recon versions of the -1 Corsairs generally had a vertical camera mounted in the modified ventral access hatch, like this:

There were at least two versions of oblique camera mounts. The earlier version had the camera pointing to the left side like so:

while the modified F4U-1Ds ran the oblique camera to the right:

Note the sliding hatch for the camera on #171. I suspect most of the mounts used a similar form of lens protection.

Anyhow, I hope this helps...

Cheers,


Dana

 

[Wurger]

 

[John10]

Hi John,

Yes, we all were confused - it's just a story that won't die. The belly window was a bombing window, but for setting up attacks on enemy ship AAA. (One version of the window story had the window used to check if the landing gear was down, even though the landing gear couldn't be seen through the window.)

The recon versions of the -1 Corsairs generally had a vertical camera mounted in the modified ventral access hatch, like this:
View attachment 588214View attachment 588215

There were at least two versions of oblique camera mounts. The earlier version had the camera pointing to the left side like so:
View attachment 588216View attachment 588217View attachment 588217

while the modified F4U-1Ds ran the oblique camera to the right:
View attachment 588218View attachment 588219

Note the sliding hatch for the camera on #171. I suspect most of the mounts used a similar form of lens protection.

Anyhow, I hope this helps...

Cheers,


Dana

Wow, so they never replaced the .50 cal gun with a camera then? I know it was just a TV show, but an episode of BAA, BAA BLACK SHEEP, it was referenced on "Last One For Hutch" episode, where "Pappy" replace a gun for a camera in the gun port, for a reconnisence mission. The real Greg Boyington was a consultant for the show and I didn't think he would let that error of fact go.
I wish I knew you a long time ago. The F4U Corsair, the 1D, in particular, was my favorite plane of WWII and and I read everything I could about the plane, find any photographs, to learn about it and I thought I knew a lot, but you put me to shame! Thank you sir, for your expertise and knowledge! if I may, I would like to quote you when relaying Corsair information to other people, and I won't look foolish again.
Thank you Dana!
John

 

[Dana Bell]

Hi John,

Many thanks for the kind words - I'll try not to let it all go to my head...

The truth is that, until a few years ago, my knowledge of the F4U-1 came from the same secondary sources as everyone else. When I started working on the Aircraft Pictorial books a number of new files had recently opened or been processed at the National Archives - I was just lucky enough to be among the first to to get into some of those boxes. By comparison, I had to put the F4U-4 book on hold, so now I know hardly anything new on that aircraft. (Before stopping, I did find that the cannon-armed aircraft originally designated the F4U-4C was later redesignated the F4U-4B.)

Anyway, part of the fun is sharing the few things I'm able to find at the Archives. I'm glad you're able to enjoy the discoveries too!

Cheers,



Dana