Page 22 - CAMPAIGN Summer 2021

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CAMPAIGN Summer 2021
Both G1 and G2 became the responsibility of the Royal Navy. Planning took place from February 1955 under codename Operation Giraffe before the Admiralty adopted the name Operation Mosaic in June 1955. The scientific director, Charles Adams from AWRE, had deputised for William Penney at Operation Totem, with Ieuan Maddock as scientific superintendent (known as the Count of Montebello as he provided all the countdowns to detonation).
surveying and marking operations of marker buoys for moorings in October and November 1955. Site preparations, including construction of the two 300ft towers, were performed by the Royal Engineers.
The Royal Engineers and Royal Navy built a shore camp, control building and camera tower on Hermite Island, and weapons towers on Trimouille and Alpha Islands. A naval meteorological
comprised HMAS ships Junee, Fremantle, Karangi, MRL 252 and MWL 251, which were anchored 12 miles southeast of Ground Zero and were named Task Group (TG) 308.2. The HMS Newfoundland, along with destroyers HMS Cossack, Consort, Concord and Comus formed Task Force 308.3; the HMS Diana was detailed to perform scientific tests for G1 and G2 in Task Force 308.4.
Leslie Martin (Australian physicist and member of the Australian Atomic Energy Commission), Ernest Titterton (British nuclear physicist who researched under Mark Oliphant), Cecil Eddy, WAS Butement (of the recently formed Atomic Weapons Tests Safety Committee, AWTSC) and LJ Dwyer were flown from Onslow to the HMS Narvik on 14 May 1956. Martell set the date of the test for the 16 May on 15 May. This was a tentative time as the AWTSC didn’t initially approve the test. Penney sent a message to Adams on 10 May, and the test was back on. Four RAF Canberra bombers flew from Pearce – two conducted cloud sampling (one flown by Menaul) around 20 minutes after firing, whilst two provided support.
The RFA Eddyrock (an Eddy Class Fleet Attendant Oiler, A198) arrived at Fremantle on 5 April 1956 to load cargo and stores for the ships at the Montebello Islands for G1, which she also took part in.
Rehearsals were held on 27 April and 2 May, followed by a full rehearsal on 5 May. The fissile material was delivered by an RAF Hastings to Onslow, and collected by the HMS Alert on 11 May, delivered the next day to the Montebello Islands. The G1 test was detonated from a tower on the northwest of Trimouille Island.
Group Captain SWB (Paddy) Menaul commanded the Air Task Group. Menaul was already a British nuclear test veteran, as he had been an observer on board Vickers Valiant XZ366, when it had made its first operational drop of a British atomic bomb at Operation Totem, Emu Field.
The Australian government formed a Montebello Working Party as a sub-committee of the Maralinga Committee set up for the future tests from September 1956 in South Australia. The HMAS Warrego (sloop) and Karangi (boom defence) conducted mooring, hydrographic
station was set up at Christmas Island, along with operational bases at Onslow, Pearce and Darwin, Northern Australia.
The corvettes HMAS Fremantle and Junee provided logistical support, ferried personnel between islands and housed the designated 14 British and Australian media representatives during G1.
HMS Alert, HMS Narvik and RFA Eddyrock formed Task Force 308.1. Captain Hugh Martell took charge as commander of Task Force 308 from the HMS Narvik. The Royal Australian Navy component