Probus – Hears How A Piece of String connects to H-Bomb Test

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How A Piece of String connects to H-Bomb Test

There will be many readers from the older generation who remember the nuclear bomb tests in 1957/8 that took place in the remote South Pacific on Montebello Islands, Malden Island and perhaps more famously, Christmas Island. David Stiles, the speaker at the latest meeting of the Probus Club of Basingstoke, while he was not one of the military personnel who witnessed the Hydrogen Bomb tests, was in the RAF but he was based in the tropical paradise of Hawaii.
Many aircraft in those days did not have the range to fly non-stop from the west coast of USA to the H-Bomb test islands. The USAF Hickman base near Honolulu on Oahu in the Hawaii islands, 1,335 miles away, became a staging post for aircraft on their flights to and from the nuclear test sites. The speaker was posted to this paradise purely because he was a specialist instrument and avionics engineer.
Hastings TG582 Xmas Island Aug 1956The RAF used Handley Page Hastings aircraft, introduced after WW2, as both cargo transporters and troop carriers. One day a Hastings, en route to Christmas Island, arrived with a top-secret VIC. This turned out to be Vitally Important Cargo. A large bulbous object was lashed securely with a tarpaulin cover that had its fastenings wax sealed. The pilot claimed not to know what it was, but most people had thoughts that it was needed for an H-Bomb test due in a few days’ time.

Late Arrival

The plane had arrived later than expected. The reason, as explained with fruitful language by the pilot, was that there was something seriously amiss with the navigational equipment that had forced the plane off course several times resulting in extended flight time. The plane was fitted with a dual system of a magnetic compass and a giro compass. A magnetic compass would behave differently the closer the plane flew to the north pole and the giro compass was there to counteract this action. On this flight it had proved impossible to make manual adjustments and the plane had veered considerably off its flight plan.
The speaker was charged with rectifying the problem and went through a series of procedures including having the aircraft physically moved around to check the compass readings which proved accurate. At the upper end of the port wing was a small square hatch cover over an electronic device whose purpose was to use signals to synchronise the giro compass to maintain a true heading. This equipment was held in position with small nuts on its underside which made it difficult to remove for inspection. In order not to drop the tiny spanner used for undoing and tightening the nuts in this very difficult position, and working by feel only, a piece of string was tied to the little spanner and looped on to his little finger so that if dropped the spanner could be easily recovered.
Spanner with stringAfter several frustratingly unsuccessful attempts at undoing one of the small nuts the little spanner slipped from his grasp. Aghast, he realised the safety string had inadvertently come off his finger. Now both string and spanner were lost but had to be found.
Feeling blindly into the dark abyss, he miraculously discovered not only the tiny spanner and string, but another huge spanner not remotely used in that area, but in the engine bay 30 feet away. How come this large spanner was under the detector unit causing huge magnetic errors for the gyro compass? Each time the aircraft banked the large spanner moved, causing yet further errors.
Ironically, by accidentally losing his little spanner and string, he discovered something that could have seriously jeopardised the plane, that Vitally Important Cargo and the testing of an H-Bomb.


The questions then centred on how did the spanner get into the sealed cavity at the end of the wing? It was the size and type used on the plane’s engine maintenance, but it could not have slid along inside the wing as the fuel tanks completely blocked any access.
Nuclear MushroomWas it sabotage? Enquiries were no doubt carried out, but no findings were passed down to this RAF NCO. His reward was to receive a promotion and eventually be returned to UK duties working on Victors, part of the V bomber force in place during the cold war.
Perhaps enemy forces had hoped that by creating navigational problems the longer flight time would have caused the plane to run out of fuel and crash into the Pacific Ocean. Two days after finding the spanner the final H-Bomb test took place on Christmas Island. Would this have happened if a tiny spanner tied to the end of a piece of string had not solved the navigational problem?



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