View Full Version : Making sure bomb bay doors are open....

5th Jun 2014, 07:23
From the Lancaster bomber pilot's notes - implications are 'interesting'.


5th Jun 2014, 07:35
I eat plenty of roughage, although strenuous pumping is still occasionally demanded. 15 minutes seems a bit much, though.

We don't get any red engines around here (plenty of brown ones a few miles away, though), but I'd imagine any occurences might induce instant release, doors open or not.

Hope this helps.

5th Jun 2014, 08:05
Me again. Something just surfaced in my memory (rare, these days)...

Anyone ever fly the Mosquito?

Story I heard was that an engine failure after take off with a big bomb on board meant you'd be going in one direction only: down. Not enough performance on one engine to lift the weight of the Mossie plus one big bomb. Forced landings with a bomb in the bay was a tad risky.

Trouble was, if you released the bomb at low level, so as to lose weight and thereby keep climbing, you ran the risk of the blast from below taking you out.

5th Jun 2014, 09:43
acbus, I might be talking out of my fundamental orifice here but weren't the bombs inert until fused during the flight?

Perhaps that was USAAF aircraft or perhaps something that came along afterwards. :confused:

blue up
5th Jun 2014, 10:27
The big 'Cookie' blast bomb minimum release height for the Lanc was, IIRC, about 4000 feet.

5th Jun 2014, 10:44
"weren't the bombs inert until fused during the flight?"

You are quite right.
However, hitting the ground just might set it off anyway.

The Shackleton, a descendant of the Lancaster, had two hydraulic pumps, one on No. 3 engine and one on No. 4. (Starboard Inner and Outer in Lancaster parlance) It was standard practice to close the bomb doors after starting No. 3, which established that that pump was working, and after a flight to shut down 1, 2 and 3, and then open the doors proving that the pump on No.4 was working.

5th Jun 2014, 11:06
If you didn't open them the ground crew could get quite shirty as yes a lot of pumping was required!!Shackeltons I mean!

Shaggy Sheep Driver
5th Jun 2014, 11:22
Story I heard was that an engine failure after take off with a big bomb on board meant you'd be going in one direction only: down. Not enough performance on one engine to lift the weight of the Mossie plus one big bomb. Forced landings with a bomb in the bay was a tad risky.

Given the very high single engine control speed of the Mossie, I'd think EFATO with a big bomb on board would lead to instant flick roll into the ground.

Richard Woods
5th Jun 2014, 12:42
If you didn't open them the ground crew could get quite shirty as yes a lot of pumping was required!!Shackeltons I mean!

Dont remind me... last weeks job was replacing the hydraulic hand pump on our Shack at Coventry, and the bleeding of the system afterwards!

I suspect whoever drew up the placement of it years ago at Avro didn't realise that given the upwards swing of the handle what a sod it would be to operate while perched on the undercarriage below it.

5th Jun 2014, 15:04
I was told it was standard practice on most IC powered aircraft to leave bomb bay doors open to ventilate the aircraft (fuel fumes) when parked.

This may be of interest.


5th Jun 2014, 18:27
I remember my father telling me that on the B-29, when loaded to the 'war load' maximum takeoff weight, if he lost an engine just after takeoff, they were going into the drink.

And the engines on the B-29 were known for quitting way too often. So after takeoff, there was about a three minute period before the crew would breath again. He told me the speed and altitude, speed being more important, that they needed to fly on three engines, but in my old age I have forgotten.

5th Jun 2014, 19:52
I'm sure I remember at least one instance in the military history books I've read of a Lancaster with bombs rattling around on the bomb bay doors when they didn't open before the bombs were 'dropped'.

5th Jun 2014, 19:53

Likewise, I remember reading about it.

Also, a "hung up" bomb in a few instances including one that detonated
on crash landing.

6th Jun 2014, 08:27
Hmnn ... we had a hung up sonar active torpedo on one of my Shackleton sorties over the N Atlantic. Can't remember which mark of torpedo it was .. but we had to activate the thing before dropping it. Activation meant mixing two chemicals which reacted violently to produce gas to run the torpedo's motor. The torpedo had to be dropped and in the sea within a short time or it would overheat/over pressure and explode. Took a lot of swearing and banging with the crash axe on the offending bomb hook (access through the floor) before that torpedo departed. :eek:

6th Jun 2014, 10:18
I thought we had to call it Mumbai these days. :confused:

6th Jun 2014, 10:26
Dr Norman Piercy (http://www.heraldscotland.com/comment/obituaries/norman-piercy-general-practioner-and-disabled-sportsman-1.1077952)

The father of a friend.

On September 9, 1944, the Lancaster in which Dr Piercy was flying was caught in a hail of flak during an aborted raid on Le Havre and only his swift actions in feathering the propeller and extinguishing the blaze when one of the engines was hit prevented the plane from being destroyed. The Lancaster made it back to its base at RAF Upwood where it landed safely and the rest of the crew disembarked. Dr Piercy remained behind to assess the damage and was caught in an explosion moments later when one of the bombs, possibly damaged by the enemy fire, went off. Five members of the ground crew were killed and the young flight engineer lost his right leg. I would often see him careering down the slopes at Glenshee on one ski, with his outrigger poles threatening anyone who got in his way. :ok:

6th Jun 2014, 20:11
Not just an old aircraft problem, either. I well remember a trials flight in a Canberra (the BI6, which will identify it to one of two, to those familiar with the type) where I tried to release a weapon three times on the range, with a hang up on each occasion. Back then we didn't have bomb bay video, just 16mm cine cameras in the bomb bay, so we returned to base and landed, following the standard hang-up procedure.

We landed, taxied to the arming area and I opened the bomb bay doors as we shut down, to let the bombheads crawl in and find out what had gone awry. As the doors opened I distinctly heard the loud thud as the 600lb weapon fell to the ground. Apparently it had come off the rack and fallen on to the bomb bay doors at some point during the return flight or landing. The door latches had held the load until I opened the doors.

It took around three or four test flights to understand why the weapon hadn't released. It turned out that there was enough lift from the airflow under the bomb bay to hold the weapon up when we were over around 350kts, even after the release unit had opened. The fix was to add a perforated baffle plate across the bomb bay, to act as a spoiler. This then allowed gravity to overcome lift and let the 600lb weapon fall clear of the bay in future.

Sadly both these aircraft have now been scrapped, but I did manage to wangle a trip on the last flight of one of them, and it's cockpit is preserved in a museum somewhere, I think.

Lou Scannon
6th Jun 2014, 20:31
One of the "Bomber Boys" who flew with 617after the Dams...and appeared in the recent John Nicholl TV episode, told me one fascinating story that I hadn't heard before.

It seems that when they were issued with the Grand Slam bombs weighing in at 22,000 lbs, a senior chap pointed out that they were terribly expensive and that the RAF didn't have many available.

If they were unable to release them on target, rather than jettison them over the North Sea, would they please bring them back?

...and apparently...they did.

Landing, I would imagine, with the crew holding their fingers in their ears!