GRAND SLAM at 60 !

Happy 60th Birthday to GRAND SLAM.

On 14th March, 1945 the first 22,000lb Grand Slam bomb was dropped on the Bielefeld Viaduct by the Lancaster B1 Special of Sqn Ldr C C Calder, 617 Squadron.

 

Was about to start singing 'For he's a jolly good fellow...' but then the morbidity of it struck me.

 

Barnes Wallis was a god of war...

 

And yet, 'Grand Slam' and 'Tallboy' were designed with true 'strategic bombing' in mind - they were not designed to kill large numbers of civilians.

 

Looks like there were quite a few near misses! How many GS were dropped?

 

At Bielefeld that day - one !

Total Grand Slams dropped on targets in 1945 : 40.

 

It did not really matter whether the bomb hit or not! The explosion also caused a huge vibration that destroyed the U-boat pens and bridges etc. Totally awesome! Hitler could order as many meters of concrete as he wished on the U-boat pens and Wallis just laughed because it did not really matter....

 

From "A hell of a bomb" by S Flower

"According to an unnamed Vickers chief mechanic, it took two skilled men one day to fit and adjust two tails..."

So it was not just putting the pieces together to make the bomb fall and reach the top speed!

 

It had to spin correctly as it exceeded the Speed of Sound.

The cave-in effect was called camouflet.

It was said one of the amazing sights was the curve in the wings of the Lanc while carrying the bomb.

(

 

I also read that once the bomb was released the plane jumped up " hundreds of ft " and many crew members hit themselves against the fuselage...

 

From Stephen Flower " Hell of a bomb"

The Lancaster with Grand Slam:

The Lancaster crossed the British coast at about 1,000 feet. From memory, we crossed the enemy coast at about 6,000 feet.....

 

i quite like these pics from wiki



"The Farge U-boat pen after being hit by a Grand Slam - note the figure standing on the pile of rubble."




"A British 22,000 lb (10,000 kg) Grand Slam bomb"

 

Damn, thats incredible.

 

Too bad cannot see the plane jump but better than nothing...

http://www.youtube.com/watch?v=O2Q2mrw9pRg

 

hmmmm, the video has been 'removed due to terms of use violation'. I was looking forward to watch it aswell!

 

Martin- Good story on grand slam- The upsurge felt on release of such a bomb would indeed be tremendous. We were well aware of the impact felt with the release of our bombload. They ranged from 250, 500, 1000, 2000 and up to the 4000 "cookie").
I"m not sure how they achieved the required lift. Our all-up take off wt. was 65,000 lbs. Now a Lancaster's tare wt. was 43,000 lbs. Add ammo, fuel and crew
and we're well over. However those boffins could do wondrous deeds those days
Cheers Alex Campbell Skipper of C Charlie 514 Sqdn

 

Hello Mr Campbell -

You're right - for the Lancaster to handle such a payload was quite an achievement. Apparently, a lot of modification work was carried out : the nose and dorsal turrets with all their associated weapons, ammunition and equipment were 'ditched' and ammunition for the remaining tail turret was reduced by 20%. In addition, the outboard bomb-loading stations and related load-carrying beams in the wings ( which were hardly, if ever, used anyway ) were removed as were, of course, the bomb-bay doors and related equipment. The fuel system was also modified as fuel for the 'Grand Slam' raids was not normally carried in the outer wing tanks.

Even with that lot, I'd imagine take-off was 'interesting' - mind you, the return flight must have been fun !

 

A great book about the Grand slam Lancasters is Beyond the dams to the Tirpitz by Alan Cooper
In the video RAF Victory by DD videos it show alot video of Lancasters dropping grand slam on u-boat pens , bridges & the Tirpitz

 

Hello, my friends!
A link about of the Grand Slam: Australian Armourers Association

 

Don't forget 9 Sqdn. They participated in many of 617's precision bombing missions, and likewise suffered appauling losses.
Tallboy related crashes see: Lost Bombers - World War II Lost Bombers
- due to fuel starvation, bombed from above, slow & reduced maneouverability due to excessive load, reduced armament... and thus easy targets for fighters and flak attack, etc. etc.

And yes, once Tallboys & Grandslams etc were released, the planes would leap upwards, often resulting in mid-air collisions since the groups flew in extremely tight formations.

Note re fuel load, stripping down weight:
"The six-man crew on this operation, (Tirpitz) is explained by the fact that, since the aircraft was operating at extreme range with additional fuel tanks. The load comprised one 12,000lb Tallboy and a fuel load of 2,406 gallons - the normal Lancaster tankage being 2,154 gallons. The mid-upper turret was removed and fared over to lighten the aircraft."

Signed by Fred Wilson:
Named after Fred Sutherland, of the Dam Busters.
- still alive, well and, with his wife, hiking Alberta's Rocky Mountains. Pic near the bottom of the page at NLS - A Dambuster's Daughter
- his escape after crashing, after successfully breaching the Dortmund-Ems Kanal at: Lost Bombers - World War II Lost Bombers

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