B-24J Dive speed? Tab area?

[daveT]

I researching the cause and recommendations of a B-24J crash. During a bomb bay door operation test conducted while diving, the elevator tabs failed causing the structural failure of the elevator which made it impossible for the pilot to recover from the dive.
Recommendations from the accident investigation board were
Further investigation and study should be made of the strength of the elevator around the tab area for all allowable flight conditions
Dive speed should be restricted to 260 miles per hour for bomb bay door operation.
According to the pilot manual that I have for the B-24D, the diving speed limits are 56,000 lbs are 275 MPH.
Questions that I have are 1. What is the dive speed restricted to in a B-24J? 2. Was the area around the tab area in the elevator strengthened in latter model B-24Js?

[ozhawk40]

Attached is the relevant page from the J pilot manual. Looking to see if I have anything that answers Q2.

regards

[daveT]

Thanks for the reply!
The airspeed limitations look like the same ones I had for the B-24D. I would of thought that they would have updated them for the J model. The date of the accident I'm researching is 19 August 1944, what is the date of the manual that you referenced? Also interesting to note the CAUTION "No dives, short turns or flight in turbulant air should be attempted" How were they suppose to fly a mission? Did they use B-24s for skip bombing missions? That would have required heavy loaded dives to low altitudes in turbulant air. Got anything else about diving a B-24?
Thanks
DaveT

[syscom3]

Dave, B24's were used in the skip bombing role in the SW Pacific. I do remember reading in the book "Morotai", written by a 307th BG pilot on how they skip bombed small Japanese ships near Borneo and Celebes.

Also, remember the B24's were also used as sub hunters and as such, dropped their depth charges from low altitude.

[ozhawk40]

Page is from the J Pilot Manual dated 25th March 1945, so no change up to there at least.

[ozhawk40]

Page is from the J Pilot Manual dated 25th March 1945, so no change up to there at least.

Attached is additional info that I have found that may assist.

[daveT]

Thats it! Thanks you very much. I now know that a change was made shortly after the accident to the tabs. They did take the recommendations from the report. The four crewmembers did not die in vein! Something was learned from the tragic event. Thanks again
DaveT