The Shackleton Story by Bill Billings (continued)
Meanwhile, development on ancillary equipment had progressed, albeit on a somewhat piecemeal basis. Saunders Roe, still very much in ‘boats’ mode, between 1952 and 1957, built about 50 airborne lifeboats for carriage by Shackletons. They were attached through a single point hole in the bomb bay, and a cluster of 4 parachutes was intended to provide a soft, bows up, landing on the water. There are two points of particular personal interest to myself here that I cannot resist recounting. I was working at the RAE Farnborough throughout 1952, on parachute and ejection seat R & D. It befell my lot to go flying in this strange aircraft – (when I first met the late Bob Becker, who was the Flight Engineer. We mostly operated with Lancs, Halifaxes and Hastings, and he was the Eng for all of them). I observed, and operated recording equipment when we dropped the lifeboat off Felixstowe. It appeared to go OK, but after that the trials were transferred to Manby; Felixstowe was obviously much to up-market for us.
The other point was the Vincent 500cc motorcycle engine that was fitted to the lifeboat; In 1955, I bought, at enormous expense, a Vincent HRD 500cc motorbike, fitted with that model engine, and I would never have let it even get wet with sea water, let alone be party to dropping it in the oggin. I also went to the 1953 Farnborough show (ticket from my old department, as I was now a prospective demi-god in blue aircrew trainee), and I saw a white Mk 2 Shack do a fly past, with airborne lifeboat underneath and engine numbers 1, 3 and 4 stopped with feathered props. I think that they dived in during the feathering cycle and restarted on the climb-out, but it looked very impressive. Many years later I learned about which engines had the hydraulic pumps, which explained why it was number 2 still under power. That was less impressive than having only an outboard running, but a certain nastiness at a flying display in Gib, many years later, in 1957, took the ‘more impressive’ theme a bit far. I am reliably informed that ‘the noise and the people’ was worse than D-Day. However, I digress; the airborne lifeboat idea lost favour and Lindholme Gear was introduced, initially with three containers and later marks with two.
There had never really been euphoria about Shackletons while they were in service, but even their Airships, some of whom had risen from Shack men, accepted that it was not really an ideal aircraft from the crew point of view for 15 hour + flogs. Noisy, gloomy, ergonomic nightmares, sods to land gracefully and, the source of ‘informed criticism’, physiological tests showed that crews were comfortable on less than 1% of their entire trips! It was thus decided in November 1953 that the balance of Shackleton orders would be filled by a redesigned aircraft, and this became the design of the Shackleton Mk 3. Design changes were sufficiently radical enough to merit a new type number. Goodbye Avro Type 696, and hello to Type 716. To fully justify the changes, investigations by the Institute of Aviation Medicine were made with (eager?) co-operation of 240 Squadron. Surprise, surprise, it was found that intensive flying in the Mark 2s caused great loss of efficiency, buzzing in the ears and sleeplessness (when not flying, one presumes). Urgency was therefore accorded to the Design and Development, especially as the last Sunderlands were due to be pensioned off at the end of their fatigue lives.
Avro really got their fingers out, and after normal ground testing, the Mk 3 prototype, WR970, made its maiden flight from Woodford on 2 September 1955, taking part in the SBAC show at Farnborough three days later. By now, Avro was becoming part of the Hawker Siddeley Group, although it would always be referred to as the Avro Shackleton.. Following the emergence of poor stalling characteristics, especially with the bomb doors open, further tests were carried out from Woodford. Some three months after the first flight of the prototype, in a tragic accident, killing the four Avro test crew on board, the prototype was lost during stall tests,. It was surmised that in a full stall, the aircraft dropped a wing, became inverted and the engines stopped. Subsequently, stall warning equipment in the form of a stick shaker was installed, and stringent measures were developed for C of G limitations. It had been found that with a C of G of more than about 4‘6“ aft of the datum, the aircraft could become unstable, wallow and become liable to easily stall (OK, Engineers, the distance may not be exact, but that was the principle). When nose guns were not fitted, concrete ballast was sometimes placed in the nose.