As a direct result of the Falklands conflict, the RAF suddenly, had a huge requirement for air-to-air refuelling tanker aircraft, to support the seemingly endless supply flights to and from the Falklands, while still maintaining day-to-day activities back in the UK, supporting fighter and offensive support squadrons.
As a direct result of the Falklands conflict, the RAF suddenly, had a huge requirement for air-to-air refuelling tanker aircraft, to support the seemingly endless supply flights to and from the Falklands (and Ascension Island), while still maintaining day-to-day activities back in the UK, supporting fighter and offensive support squadrons.
As explained by Tim McLelland in his book The Avro Vulcan Revised Edition, the Victors were heavily committed to the AAR task, and although the conversion of VC-10s into tankers was under way, there was still a short-term requirement for even more tankers. While the USAF supported RAF operations in the UK with Boeing KC-135 tankers, it was decided to convert a number of Hercules and Vulcan aircraft into single-point refuelling tankers. The initial proposal, sent to British Aerospace at Woodford, was to install a Hose Drum Unit (HDU) in the aft section of the Vulcan’s bomb bay, the Vulcan then being designated B(K) 2. But this idea was dropped, mainly because of the resulting proximity of the receiver to the tanker aircraft. It was felt that, for safety, the HDU should be placed as far aft as possible, to provide adequate separation between the tanker and receiver. The ECM bay was identified as being a suitable location (the internal equipment being unnecessary for tanker operations), and this would also allow an additional fuel tank to be installed in the bomb bay. XM603, which had been delivered to Woodford after retirement for static display, was used as a mock-up platform and, as J. J. Sherratt, BAe’s Assistant Chief Designer for Victor tanker systems, explains, the task of fitting the HDU was far from simple:
`Sunday morning saw a group of us standing around a crated HDU, thinking that if it was anything like the size of the crate, we wouldn’t stand much of a chance of fitting it. Even with the crate removed it looked big, but by this time we had resolved to get it into the Vulcan even if it meant restyling the back of the aircraft. There was no way of straight-lifting the 51/2-foot-wide HDU through the existing ECM opening of 4 feet, but we noticed that the top part of the HDU could be separated from the bottom, and we might be able to get the top half through the opening, leaving the bottom half to be straight-lifted in. A piece of wood the same size as the top section was called for to investigate the possibility. The verdict was that there was plenty of room if we had a good shoehorn, and if necessary we could put the odd blister here and there to cover any awkward bits.
‘ After a design team meeting in the afternoon, we agreed to tell the MoD that we could do the job, and in the general euphoria a target of three weeks to first flight was set. On Monday two representatives from Flight Refuelling arrived to advise us on splitting the HDU, and at around midday we received authority from MoD to proceed with the conversion of six aircraft. The first aircraft, XH561, arrived on Tuesday, by which time a whole army of workers had been mobilised to work all the hours it needed to do the job. Seven weeks later to the day, on Friday 18 June, the first converted aircraft made its first flight at 12.32pm. An interim CA release was granted on 23 June, and the first aircraft was delivered to the RAF on the very same day.’
Sadly, the Vulcan K.2 did not enjoy a particularly long career with the RAF, as although the Vulcan proved to be an excellent tanker aircraft, the HDUs had been out of production for some time, and the Mk 17 HDUs fitted to the Vulcans had already been allocated to the VC-10s, which were being converted to tankers. As the VC-10s were completed, the HDUs were removed from the Vulcans, starting with XJ825 on May 4, 1983.
On Mar. 31, 1984 No 50 Squadron, the last operational Vulcan unit, disbanded at Waddington, leaving its fleet of six K.2s and three B.2s to be delivered to museums and fire dumps.

The Avro Vulcan Revised Edition is published by Crecy and is available to order here.
Photo credit: BAE