LOUD . . . . !!!

Switching Pedant mode on, Tallboy was designed by Barnes Wallis, not some random Scotsman.....

Well done GeeRam. What a wonderful find great research . This is why I love pprune.
Its a miracle that during all the reworking of the waterway post war, this UXB wasnt disturbed earlier.
That would have taken the edge off someone's day.

I suspect that was why the bomb was found nose up, I reckon there's a very lucky dredger crew around there . . .

They found as a result of dredging operations

https://www.sciencealert.com/five-to...ing-defusal-op

Amazing film footage from the raid

Totally agree, even the missus found it interesting! Best of Pprune award certainly.

Assuming the part about it being nose-up isn't a reporting error - that's very curious. Although dredging may have disturbed it, it would be unlikely to rotate it 180 degrees while leaving the bomb almost entirely covered.
I wonder if the tail fins detached/failed, and the bomb tumbled instead of heading in nose-first. That could also explain why it didn't detonate - landing tail first.

Yep, that's my view as well. Wallis designed the Tallboy fins to spin the bomb on decent, so it would go down vertically, for the penetrative earthquake effect, so a problem with the fins and landing tail fist would indeed account for this.

The saw tooth dock structure appears to have been created by subsequent bombs hitting the dock a few seconds later.

Agree this really is a great find.

I met Barnes-Wallis when I were a young-un many moons ago at Vickers in Weybridge, he seemed a very calm, well-mannered gentleman, maybe a little eccentric, but even then his fame for his achievements was enough to shut up the brash youngster I was then. There used to be a Tallboy and Grand Slam parked against the Brooklands circuit clubhouse, probably still there and if so I'd recommend anyone who has the chance to go and look at them, impressive does not do them justice and it brings home the enormity of what they, BW and the RAF achieved.

https://cimg5.ibsrv.net/gimg/pprune....8cb8327346.jpg
Lost something? Scrap yard near Tetney, Lincolnshire

It’s along the lines of “Alle strzelilo“ :-)

A Tallboy in a scrapyard!! Well, after the war I guess there was not much need for them for a while, but it does seem an unfitting place for such a thing! Though perhaps better than in a 617 squadron bomb bay!

How were these things detonated? Presumably you didn't want them going off on impact but wait until they buried themselves a bit.

They moved them inside in the 90s, Brooklands Museum has an example of all the bombs Wallis designed.

There was a story about a Grand Slam or Tallboy on display somewhere that, after years on display, was found to be still filled with explosive. Does anyone remember where?

RAF Scampton IIRC.

I took this photo at RAF Lossiemouth in 2009 - Tallboy, Upkeep and Grand Slam....I met Barnes Wallis in 1963 when I attended a lecture he gave. Fascinating guy, quite unassuming.

https://cimg6.ibsrv.net/gimg/pprune....30c143a403.jpg

Hush Hush
 

When I went on ATC camp to RAF Catterick several decades ago there was a very large bomb behind a curtain in one of the hangars.
Upon asking to see it I was informed it was secret and then we were escorted out.
In the evening going to 'dinner' I noticed the side door to this hangar slightly ajar, and popped in to have a peek. It looked remarkably like a tall boy, but of course had no name on it.
RAF Catterick at the time was an RAF Regiment station which makes sense. In fact it was a great camp (with very good food) and a fire/rescue dump that would make you weep today, with 'Many' complete airframes of seemingly new (old) machines which included wonderful Piston Provosts and several early Hunters.

TNT and RDX are very stable explosives.

Didn't meet Wallis but in about 1965, we did a school visit to Brooklands and were ushered into the great man's office in the old race control tower where we were told he still came in to work a few days per week; his Swallow VG models (used in the early experiments at Predannack(?) were there.
Years later in 1973 when I was training at Northern Radar, RAF Lindholme, the RAF bombing school had a Tallboy outside along with a Blue Steel.
More years later at Farnborough, I had the privilege of 'controlling' the Vulcan which did a flypast salute at his home in Surrey after he died.

Would you have heard it though? It was supposed to detonate underground; sure there would have been a helluva shock wave but would you have actually heard much?
We felt the shock wave from the explosion at the Hemel Hempstead oil terminal years ago (whole house shook) and we're 30 odd miles from there in Surrey.

Apparently it had three tail pistols no. 58 mk1. The description is as follows: https://bulletpicker.com/pistol_-tail_-no-58-mk-1.html

Regarding the Tallboy description, is as follows per "British Explosive Ordnance NAVORD 1665 10th June 1946", page 49
Detonators—Sensitive type, delays up to 60 min. as required operationally.
Exploders
- Primary: 2 ring and 2 solid C.E. pellets; 4 solid RDX/Beeswax pellets
- Secondary: 2 ring and 2 solid large RDX/ Beeswax pellets (placed in a special exploder tube into which the standard exploder container fits).

https://bulletpicker.com/bomb_-12000...-1-tallbo.html

https://cimg7.ibsrv.net/gimg/pprune....e068f126c2.png

Thanks for that Beamr.
Are there any recorded instances of the Germans trying to defuse one?

Take a look at this, apparently they succeeded: https://www.britishpathe.com/video/V.../query/GERMANY

Seems like the tail section and detonators are already removed. I wouldn't want to do that for a living.

https://cimg6.ibsrv.net/gimg/pprune....261bf24cf3.jpg

Interestingly, apparently in total three Tallboys were found unexploded at Sorpe dam in ´58/´59. The first one found in 1958 was defused 6th of Jan 1959, and this is mentioned in many sources throughout the internet.
BUT: the Reuters news video linked above has the headline "More Tallboys Discovered In Germany" with comment "Two more RAF 5 1/2-ton 'tallboy' bombs were found, Jan 19, in the drained Sorpe dam reservoir, North Rhine-Westphalia."

So its four tallboys with the polish one counted for, I reckon there must have been more. Or be more yet to be found.

Sorpe dam raid took place on 15th October 1944 by eighteen Lancasters of 9 Sqn. Sixteen bombed with two hits on the crest and another three on the air side. However there was no breach possibly due to the Germans lowering the water level so reducing the pressure on the water side of the dam. No losses.

All of the bombs were supposed to be fitted with delay fuses - twelve with a 11 second delay and the other six on a 30 minute one. However it later emerged that at least two bombs were fitted with direct impact pistols. Again there was a mosquito camera aircraft present filming the attack.

Perhaps a little something lost in the translation?

Post attack recce picture of Sorpe Dam post Tallboy raid. No wonder UPKEEP couldn't do the business!

Makes me wonder, since three of those were later found unharmed in the reservoir and one in a riverbed, if the design of the bomb (tailfuse for use against hardened structures) caused it to fail when hitting water with sufficient depth.

Actually, the "saw tooth dock structure" is a ferry loading/unloading dock. I doubt it was created soley because of the bomb. See here:
https://goo.gl/maps/Af61GwnvF58ByLU8A

And here is a post-bombing recce photo, taken 25 April 1945 (attack occurred 16 April) showing the damage to the canal vicinity, and the Lützow settled in the shallow water. The visible craters all match up nicely with the strikes seen in the video linked earlier in this thread. It is clear from this photo just how devastating that bomb between the dock edge and the battleship hull must have been!
https://commons.wikimedia.org/wiki/F...April_1945.jpg

Spot on, I'd say, as this 'quick and dirty' overlay of the recce photo on a modern Google Earth shot shows! ;)


https://cimg7.ibsrv.net/gimg/pprune....e4a11902b0.jpg

I love the details of the fuze and bomb body, I would love to see one in action live just not too close

While working on a project in Munich in the mid 80,s a 4000lb RAF Blast bomb was found on site. It looked like a water tank or immersion heater but was identified as a bomb by German Project Manager who called out local German bomb disposal unit, who turned out to be very matter of fact about the thing, as it was not unusual back then, and indeed is still not that unusual today. Talking to them later, they explained the failure rate on allied bombs was quite high, I think it was 15% from memory, but it was a while ago so it could be more, or indeed less. The reason they said was that allied bombs when being developed were typically dropped onto harder ground than that which covers most of Germany, and many bombs just literally sank into the loam. I am not sure if that is correct, but it would seem logical, or it was just poor manufacturing. They said Berlin was the worst place for unexploded ordnance of all types due to the extensive street fighting as well as the heavy bombing, the next worst unsurprisingly was the Ruhr valley cities.
Cheers
Mr Mac

"TNT and RDX are very stable explosives."

A wise man who wishes to live long will treat that as a relative statement

it's best to treat all explosives as if they are loaded guns - they're really designed to go off

The full story in this book, which I recommend.
https://cimg1.ibsrv.net/gimg/pprune....489824e58c.jpg

Big brother of Tallboy here at Bielefeld Viaduct

Speaking of fuses, I read about a device - limpet mine I think - that used a boiled lolly as a delay.
Water got in, dissolved lolly, and BANG. Talk about effective low tech!

The assembly of the detonation powder train of a bomb is called a "fuze".

Cool mechanism as a timing device, the lolipop



​​​​​Sorry for pedantry

I recently drove to the Bomber Command Museum in Nanton, south of Calgary, to see the reproduction Grand Slam and Tallboy that the museum had recently acquired. Very impressive to see in "in the flesh".


https://cimg2.ibsrv.net/gimg/pprune....1331d604b3.jpg

https://cimg7.ibsrv.net/gimg/pprune....fe438a3066.jpg

On the starboard side of the Lancaster is an Upkeep mine. I didn't take a picture of it, because I thought I had one!

https://www.bombercommandmuseum.ca


PS Pugilistic Animus, do pedants have short fuses? ;)

Berlin is in an area of low-lying marshy woodlands with a mainly flat topography, part of the vast Northern European Plain which stretches all the way from northern France to western Russia. The load bearing ability is such that Hitler had a 12,000 ton test building erected to see if the soil would be able to support the planned buildings of Germania. The test piece still exists.


https://cimg6.ibsrv.net/gimg/pprune....ee60426f90.jpg

[QUOTE=PS Pugilistic Animus, do pedants have short fuses? ;)[/QUOTE]
I think that I have a pretty long fuse because I am a firework :}