The BIGGEST Non-Nuclear bomb in World War 2 used by the RAF

in march of 1945 15 specially modified avro lancaster bombers of 617 squadron were on their way to a strategic target in western germany the allies have been attempting to demolish the blfl viaduct using thousands of bombs since the beginning of the war but with no success this time however the 15 lancasters were carrying just a single bomb each each one capable of destroying the very foundations of the target one of which was a bomb that the world had never seen used before the grand slam during world war ii the main weapon used by raf bomber command was the general purpose bomb now as the name suggests this weapon attempted to satisfy a range of requirements and came in a variety of weights and explosive yields but it did have significant limitations the general purpose bomb used a thick walled metal casing with an explosive filler and the earlier british versions had a charge-to-weight ratio of around 27 percent that is to say only 27 percent of the whole weight of the bomb is actually explosive now as a comparison the germans were using general purpose bombs that had a charge to weight ratio of around 50 percent the british response to this was to upgrade their bombs to medium capacity bombs this improved the charge-to-weight ratio up to at least 40 percent and coupled with a new filler with more explosive power it was a marked improvement another limitation and perhaps more significant was that general purpose bombs are designed to explode either at or near the surface and destroy their target directly by explosive force the most assured way to achieve destruction of the target is a direct hit unfortunately bomb aim and technology at the time was poor and therefore so was accuracy and so to improve a bomb and raid's chance of success bomber command used area bombardment dropping large numbers of bombs over a wide area in the hope that the target would be hit this obviously had the disadvantage of requiring large numbers of aircrafts carrying large numbers of ordnance and the inevitable collateral damage including terrible civilian death numbers it was also a limitation that due to the shortcomings of the general-purpose bomb it was quite easy to fortify critical installations using thick concrete walls a possible solution to this problem had been undergoing investigation since the start of the war by the english engineer and inventor barnes wallace he had a theory that an exceptionally large very heavy bomb highly aerodynamic to achieve high speed and with delayed detonation would be able to cause the destruction of a target through shock waves being transmitted through the ground this theoretical bomb gained the nickname the earthquake bomb his idea was to build a bomb 10 tons in weight with a hard armored tip and to drop it from a height of 40 000 feet the speed it would achieve in freefall he hoped would be almost supersonic and would have the effect of a 10 ton artillery shell being fired straight down into the ground a delayed action fuse would allow sufficient time for the bomb to penetrate deep underground and the explosion would cause a shockwave equivalent to that of a 3.6 magnitude earthquake the explosion would not need to breach the surface as the shock waves would create a cavern underground which would then collapse removing the foundations of structures or buildings on the surface the need for a direct hit on a target is therefore no longer required as just being close by to target such as dams railways viaducts and even reinforced buildings will cause considerable damage or even complete destruction as there was no aircraft available to carry such a bomb to such a height wallace even designed a heavy lift high altitude bomber specifically for the job the six-engined victory bomber sadly for wallace these ideas didn't gain a lot of traction from the military decision makers at the time and so wallace switched his attention to another radical concept the bouncing bomb the success of operation chastise on the 16th and 17th of may 1943 had shown that not only had wallace been successful with his innovative designs but also that the raf now had a very capable heavy bomber in the avro lancaster they now actively encourage wallace to revisit his earthquake bomb although no contracts were signed until they had been proven to work the first design for his earthquake bombs was called tallboy it had a mass of approximately 12 000 pounds a length of 21 feet and a diameter of 38 inches to prevent the bomb breaking apart on impact it was cast in one piece of high tensile steel and it was shaped to be as aerodynamically clean as possible to allow it to reach a much higher terminal velocity than that of traditional bombs the fins attached to the case enabled it to spin as it fell giving it much greater stability and prevent tumbling and therefore enhance its accuracy it was designed to be released from eighteen thousand feet and a forward speed of 170 miles per hour these release figures would mean it would impact the ground at 750 miles per hour with enough energy to make a crater 80 foot deep and 100 feet across and also penetrate concrete up to 16 feet thick the bomb was packed with an explosive called torpex that was 50 percent more powerful than tnt by mass and had only been in use since 1942 it had to be melted and then poured by hand into the bomb casing and after filling a one inch layer of pure tnt was poured over the top of the torpex before sealing with a composite wax the precision manufacturing process meant that these bombs were incredibly expensive and so were only to be used against high value targets where no other option was viable and aircrews were also instructed that all unused bombs be returned to base rather than jettisoned at sea due to the heavy weight of the tall boy as well as the high release altitude the avro lancasters needed alterations to save weight they had armor plating removed as well as some defensive armaments the bombay doors also had to be modified to accommodate such an enormous payload the first use of the tallboy took place on the night of the 8th of june 1944. two days earlier allied forces had stormed the beaches of normandy as part of the d-day landings intelligence revealed that a german panda division was heading west to engage the allied invaders they were traveling by rail and were expected to use a railway crossing over the loire river as well as a railway tunnel shortly before 11 pm on the 8th of june 1944 25 lancasters of 617 squadron successfully got airborne from raf woodhole spa and headed for sawmill western france such was the hasty nature of this raid three lancasters could not get loaded in time and so didn't take part of the 25 lancasters six were carrying eight one thousand pound general purpose bombs and nineteen were carrying tall boys to help with accuracy three de havilland mosquito aircraft of the 83 squadron pathfinder force were at the head of the flight at approximately 2 am they were over the target and launched flares to assist the arrive in lancaster bombimas and all the bombers released their tall boys successfully several direct hits were reported causing the rear wheel lane and the bridge to be destroyed one tall boy actually bored his way through the hillside and exploded in the railway tunnel which was 60 feet below the surface causing a complete blockage all of the aircraft returned safely to base the tallboy was a complete success and would continue to be used for the remainder of the war against notable targets such as v2 rocket assembly bunkers and the bismarck class battleship terpids now whilst all of this was a vindication of wallace's designs he was still thinking of his original concept of a 10-ton earthquake bomb and work was well underway to build this larger version of the tall boy it was essentially identical to the tall boy just on a bigger scale and called grand slam it had a mass of 22 000 pounds a length of 26 feet 6 inches and with an added tail length of 13 feet 6 inches and a diameter is 3 foot 10 inches with a charge to weight ratio of 50 percent it had a blast yield equivalent to 6.5 tons of tnt making it by far the most powerful non-nuclear weapon used in world war ii and just like its smaller sibling it was filled with molten torpex and such was the quantity required it would take a whole month before it was set the long complex manufacturing process as well as this cost meant that just like the tall boy an undelivered bomb would have to be returned to base rather than jettisoned at sea as a result crews were instructed to divert to raf carnaby in east yorkshire to make use of the longer runway it was still intended to be dropped from forty thousand feet but mighty as the avro lancaster was proving itself to be this was still unachievable and would have to be dropped from altitudes typically around 15 000 feet and even then the lancaster would have to be modified substantially 32 lancaster b1 specials were built and supplied to 617 squadron they were fitted with upgraded merlin 24 engines with paddle bladed propellers which gave more power the removal of the fronts and mid upper gun turrets removed weights and also improved the aerodynamics and whereas for the tall boy the bombay doors were adapted for grand slam they were removed completely also the undercarriage had to be strengthened to allow for the added weight should the bomber have to land with an undelivered weapon the first b-1 special aircraft arrived on the 5th of march and 617 squadrons canadian commander group captain johnny falcier had a grandson loaded on board and he took her for a test flight to check the lancaster's handling he recalled that he was becoming concerned during the takeoff role as he would normally be airborne at 110 miles per hour but he was still stuck to the ground at 145 miles per hour finally though and with the wings bending up at a startling angle the aircraft left the ground and following a 20-minute flight he landed safely and declared the lancaster safe to carry the grand slam on the morning of the 13th of march the grand slam was dropped for the first time over the raf bombing range at ashley walk in hampshire it left a crater 30 feet deep with a diameter of 124 feet the test drop was a success later that same day two grand slams were prepared with 11 second fuses one was loaded under group captain falcao's aircraft and the other to that of squadron leader charles calder the raf had a target in mind since the beginning of the war the bielefeld viaduct in western germany which carried the strategically important harm minden railway lane had been subjected to several attacks and over three and a half thousand tons of bombs had been dropped although regularly being damaged it had stubbornly refused to fall now two grand slams were on the way along with 18 other lancasters carrying tall boys however frustratingly the raid had to be aborted due to cloud obscuring the target so the next day the 14th of march 1945 16 lancasters would try again two lancaster group captain falcao and scotland calder were armed with grand slams and the remaining 14 with tall boys during startup focus lancaster developed an engine fault and had to be withdrawn leaving the squadron either calder to deliver the single grand slam like previous tall boy missions the target was to be marked by four de havilland mosquitoes of the pathfinder force and there was also a mosquito of 627 squadron to film the attack shortly after 1 30 pm 15 lancasters roared into the sky from raf woodhull spa in lincolnshire and headed east accompanied by an escort of p-51 mustangs and by 4 30 pm the squadron was over the target squadron leader calder's aircraft came in from the south and released the grand slam from a height of 12 000 feet as the bomb departed the bombay the lancaster lurched upwards when free of the enormous weight the grand slam now accelerating towards its terminal velocity was right on target for the viaduct spotters another aircraft and the film in mosquito reported that the grand slam impacted the ground approximately 100 feet to the side of the viaduct 11 seconds later with tall boys detonating all around it the grand slam exploded it was hard to distinguish which damage was called by tallboys and which by the grand slam but it is true to say that alongside where the grand slam hit a 260 feet span of the viaduct was demolished later reconnaissance photos also showed that at the north end of the viaduct another 200-foot span was destroyed the mission was a complete success and all aircraft returned to base safely during the remainder of march 1945 a further 156 day sorties were flown comprising of 40 tall boys and 31 grand slams by the end of the war 41 grand slam bombs had been dropped bomber command chief arthur harris was suitably impressed by barns wallace's invention and he had been drawn up several plans to use it to attack heavily fortified targets before victory in europe was declared on tuesday the 8th of may 1945. thanks for watching please help to grow this channel by hitting the like button and consider subscribing for more content [Music] you

Channel: The Northern Historian

Views: 1,214,665

Keywords: RAF Grand Slam, Earthquake bomb, 617 squadron grand slam, barnes wallis earthquake bomb, Grand Slam, what was an earthquake bomb, Grand Slam Bomb, What was the grand slam bomb, who dropped the earthquake bomb, Raf Grand slam bomb, bielefeld viaduct bombing, bielefeld viaduct grand slam, bielefeld viaduct raid, Tallboy, Tallboy Bomb, barnes wallis, barnes wallis bombs, RAF Raid on saumur, Avro Lancaster B1 Special, 617 Squadron, 617 squadron tallboy, johnny fauquier

Id: -F7PbHSkFYI

Length: 14min 30sec (870 seconds)

Published: Mon May 31 2021