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Collin
June 22nd, 2009, 16:01
Thought this diatribe would be better here then in a thread on the CFS2 forum.

This thread describes the first flexible deck and jet trials landings on board HMS Warrior, May 1948, and is quoted from the Colossus class Bible by Neil McCart.


By 5 May a small RN complement, including the RM detachment, were on board manning Warrior and the dockyard was busy fitting what was to be known as a 'flexible deck'. With jet aircraft operating from the Navy's carriers, there was no longer a ground clearance required for propellers and it was proposed that jets (both Navy and RAF) without undercarriages could land onto a flexible deck, or yielding surface, and Warrior was chosen as the carrier on which this new and unusual idea would be tested. The flexible deck, which was in effect a huge 3 1/2" thick rubber carpet, was superimposed on the existing flight deck, extending from the after end of the island to an athwartship's line 150ft from the round down. In addition a false steel deck was installed at the same level as the carpet, between the aft end of the flexible deck and the round down. This area was 'funnel shaped', and its forward end was the same width as the rubber carpet, but it tapered off aft until it ended in a short section at the round down. The false deck was marked with a 12" wide white line throughout its length, which also indicated the centre of the rubber mat, whilst the false round down was painted white. Towards the end of the subsequent trials the false deck was overlaid with a second flexi deck consisting of a single layer of 7" diameter pnuematic hoses with 2 layers of dinghy fabric. This was intended to provide a cushion in the event of a pilot touching down in this area after failing to level off, or because of the ships movement. In retrospect, viewed from 55 years after the trials, it is difficult to take them seriously, but at the time it was thought the weight-saving aspects would justify them.

During the forenoon of Tuesday 9 November a trials party from RAE Farnborough embarked, among them Lewis Boddington, who was head of the Naval Aircraft Dept and the man behind the idea of 'undercarriageless' deck landings, and that afternoon Warrior steamed into the Channel to begin the experiments. In the event, however, bad weather put paid to any landings that day and it was the forenoon of 12 November before the first aircraft left Farnborough and headed for Warrior. Flown by Lt-Cdr Brown, the first specially adapted Vampire jet had the underside of its fuselage strengthened and fitted with skids and, since it was expected to penetrate well into the flexible deck, a device had been incorporated in the arrestor hook to retract the flaps on landing and so keep them clear of the rubber mat. Although Brown had first made landings on a flexible runway at Farnborough in 1947, it was the first such attempt on a carrier and at 10.35 after 2 dummy runs, he approached the flight deck and as he later reported:

"On the approach at about 100-102 knots, I aimed at the white painted narrow funnel round down as the spot at which I would start levelling out to give myself 100ft of run-up. Although my height above the round down was higher than I had anticipated, I found myself forced up to it by the moderate pitch at the stern, and the turbulence low over the round down."

Fortunately the landing went without a hitch, and once at a standstill the aircraft was lifted onto a trolley by a special crane, as the second stage of the trial consisted of striking down the aircraft as quickly as possible. Brown made 3 more landings that day and recalled:

"When attempting the fourth landing, the deck was pitching and heaving slightly and I just failed to pick up the arrestor wire and, continuing on my flight path, struck the forward end of the flexible deck with sufficient force to record 0.4g and 2.0W on the accelerometers which were switched on, but the aircraft bounced off into the air at a fairly steep angle and remained airbourne with a little forward pressure on the stick. A successful landing was made on the next attempt."

Following the landings, take-offs were carried out by means of a detachable 'tricycle' undercarriage, which were the first such launchings from a carrier. The flexible deck trails continued throughout November and into the first week of December, but during one landing Brown reported that:

"The port wing of the aircraft struck the arrestor wire which was rising on that side under roll. A successful landing was accomplished with minor damage to the leading edge of the port wing. The next 2 attempts at landing were unsuccessful, for although the arrestor hook picked up the wire on both occasions, there appeared to be whip characteristics associated with the tension in the span."

The first phase of the trials ended on 6 December when Warrior returned to Portsmouth Harbour for the trials party to disembark.

19 January 1949, Warrior once again embarked the trials party, which also included an observer from the US Navy, and on 25 January she put to sea to resume the landings on her flexible deck. By this time more pilots had been trained in this unusual landing technique, and Lt-Cdr Brown laid out three 'golden rules' for the landings:

"1. Regard every attempt at landing as a potential miss, and be prepared to act accordingly.
2. Tend to err on the high side rather than try to ensure a contact by dipping low on onto the arrestor wire.
3. Keep on the fast side of optimum landing speed rather than low."

The trails continued for several months and by the time they were completed on 3 June over 200 landings had been made on Warrior's flexible deck.They were meant to demonstrate that the technique could be used by all pilots and not just test pilots, but although the flexible deck trials were hailed as a great success, nothing came of them and the subsequent report was left to gather dust at RAE Farnborough.

Hmmmmm......not to sure what would happen if you had a hung-up bit of ordnance on a wing if this idea had been put into practise.

Any further comments?

regards Collin:ernae:

Togo
June 24th, 2009, 12:34
I believe the idea came up because of the poor range of jet fighters. Take the undercarriage out, replace it with a similar weight of fuel and you have a longer range fighter.

Good to see another version of the trials, the only one I've seen before is "Winkle" Browns'.