F4U using gear as divebrakes
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Last update - 16 July 1998
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An interesting point was raised on AGW in the third week of July, 1998, about using the gear on the Corsairs as dive brakes. By coincidence I had just been looking at the picture below which comes from a PDF file stored on Naval Historical Center site. They have released a few PDF files concerning Naval Aviation in the Korean War. The most pertinent articles in the thread are reprinted below in case you missed them.

After mailing some of the people below I made contact with DJ Miller (Magic)who shed further light on the photograph. It appears that the photo is not of a Corsair using it's gear as dive brakes in a dive bombing attack... Suvs also came up with some more information which relates to the real world aspects of the thread, and Kergan provided some more advice on divebombing in Warbirds.

Many thanks to everyone for providing us with more information.

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Posted by: -lynx- (13 SQN RAF)

Message: I can't remember where I've read about it but I was pretty sure that F4Us used gear as dive brakes. Until Sunday. There I was, in a heavy hog at 8K over F29, deployed gear, cut the throttle and pushed the stick forward... As soon as the airspeed reached 300 kts I heard that 'gear-is-not-particularly-happy' sound and ended up with it stuck in 'down' position...

Can anyone clarify whether landing gear can/could/should/shouldn't be used as dive brakes? If not - how do you slow down diving F4U? Thanks

Posted by: Magic- [VMF-214]

Message: : I can't remember where I've read about it but I was pretty sure that F4Us used gear as dive brakes.

Correct. The Corsair had the ability to partially extend the main landing gear for use as an air brake during dive bombing attacks. For reference I site "The Great Book of World War II Airplanes", published by Wing and Anchor Press 1984, ISBN: 0-517-459930. The Marines use of the Corsair for ground attack is well documented in other sources. So, those who say it is best used as an air supriority fighter are simply uninformed. All Marine pilots must successfully complete training to perform both roles (then and now) or they don't get their wings.

Magic- [the Green one]

Formerly: DJ Miller, Capt. USMCR / Naval Aviator

Magic sheds some light on the above photgraph:

There is an interesting side note to that particular photo. The F4u's in that photo were not using the gear as dive brakes. They were level bombing from the landing pattern and didn't even bother to retract the landing gear at all.

The target was about 1/4 mile from the end of the runway on Pelileu. It was called "Bloody Ridge" by the men of the First Marine Division conducting the attack. I site as my reference: Personal interview of PFC. Curby E. Miller, USMCR, based on his eye witness account of the events that day.

BTW, PFC Miller is my Dad.

Posted by: Kergan (VMF-214)

Message: As soon as the airspeed reached 300 kts I heard that 'gear-is-not-particularly-happy' sound and ended up with it stuck in 'down' position...

: Can anyone clarify whether landing gear can/could/should/shouldn't be used as dive brakes? If not - how do you slow down diving F4U? Thanks.

REALLY? I've never had problems with the gear getting stuck when I use it for dive brakes. And I spent most of yesterday practicing dive-bombing on the reds. Here's what I do for a dive-bomb: between 7 and 10 K directly over a base, chop throttle, drop gear and deploy flaps to fullest extent ( a bit of a cheat when you have WB auto-retract flaps ). Dive. Aim. [If extreme precision is required (**#^%^& hut), once lined up hit Ctrl-X to set trim to give you no-drift drop on target.] Release. Pull out ( generally at 1-3 K). Extend for home [or] Extend for hammerhead to begin strafing if part of a group attacking at once. I dont think I've ever had my gear stick down.

And don't listen to these guys who say "use the Corsair for fighter only, its what its best at." Marine pilots are marines first, pilots second, and ground pounding is what the mud-huggers appreciate - not your AtA kill streak. If IMOL would just give us some troops to give close air-support to, we'll be happy.

Perplexed at your gear problem,

Kergan

Kergan added the extra note (in red above) as advice for divebombing in the F4U variants in Warbirds.

Posted by: Suvs OC 13 Sqdn RAF

Message: : Well, i dunno about historically, but in wb you shouldnt use the gear as dive brakes. The hog is not a bomber, it's a fighter, it will reward you the most when you fly it as such. There is no way to slow down your dive except cutting the throttle.

According to the Air Ministry's Pilot's notes for the Corsair III (F4U-1d) the limiting speed for Gear deployed is 350 KIAS (388 MPH IAS). It is quite easy to exceed this speed during a dive bombing attack though.

Suvs

Suvs adds the following information to this page too:

Got some more about F4U gear for you. All of the following is taken from the Air Ministry Pilot's notes for the Corsair I-IV for RAF and Royal Navy pilots.

Para 7

(i) On early aircraft the undercarriage control is a spring-loaded knob situated below the left-hand side of the instrument panel. To raise the undercarriage, pull out the knob, release the safety catch, and move to UP. To lower the u/c, pull out the knob, and move to DOWN when the safety catch will be automatically engaged. After setting the control to UP or DOWN ensure that the pin on the knob engages with the hole in the quadrant. The main wheels are used as dive brakes and may be lowered or raise independantly of the tailwheel by the control on the left of the u/c indicator.

NB. on later aircraft the dive brake control is combined with the u/c control.

Para 44 Flying Limitations

(iii) Dive Bombing

Maximum speed (u/c up)... ... ... ... 375 Knots IAS

Maximum speed for lowering u/c (dive brakes)... 250 KIAS

Maximum speed u/c down ... ... ... ... ... 350 KIAS

Posted by: yoss

Message: : Well, i dunno about historically, but in wb you shouldnt use the gear as dive brakes.The hog is not a bomber, it's a fighter, it will reward you the most when you fly it assuch. There is no way to slow down your dive except cutting the throttle.

VF-17 first used the Hog as a bomber. They rigged up the gear so that only the main gear (not the tailwheel) could be dropped, which worked well as a jerry-rigged dive brake. This works well in WB, and you can drop gear at relatively high speeds (compared to most other planes, this makes landing the F4U a breeze). However, like ik says, you also have to throttle back. The gear can't take ENORMOUS speeds.

Yoss 8X

The picture on this page comes from the article Fire Bomb (napalm bombs in Korea) published in May 1951 issue of Naval Aviation News Magazine. The full article can be downloaded as a PDF file by clicking on the link.