Flew the Gnat Once
There were some handling problems with the early Gnats which I hope were sorted by the my fellow TPs. Some of those early problems may not be relevant to the current unfortunate circumstance.
Following is an extract from memoirs:
During November 1957, I took the opportunity to fly some more of A Squadron's aircraft. First the Folland Gnat XK767. The Gnat was well named. It was a tiny 'go-kart' aircraft which was very nimble for its day. It had one bad feature which caused the demise of some early pilots. The main wheels were too far to the rear, requiring significant elevator power to raise the nose during take-off. It was vital that the elevator trim be fully nose-up and then extended to an override position to have any possibility of rotation for take-off.
The Gnat I flew had a redesigned elevator system. Instead of a trimable tail plane and separate elevator, this one was the first to have a fully flying elevator. This had given the tail greater effect but had introduced another problem. It suffered severe short-period longitudinal oscillations throughout its speed range. These had been recorded between +5 and -3 g at about 2 oscillation per second. Balance weights and other fixes had greatly reduced the problem. But not before one of Folland's test pilots lost the complete tail assembly at high speed and at low level. He was most fortunate as the tail pitching moment was zero at the time, thus giving him time to eject.
If anything I was over-briefed on the take-off problem to the exclusion of other aspects. On the ground, I found I could stand beside the cockpit and lean my head inside to be able to see all controls and switches. There was still the need for the trim over-ride. The control was a separate switch low on the right side of the instrument panel. This was badly placed, requiring a change of hands to operate.
I took care to set the trim over-ride and to release the brakes with the stick hard back against the stops. The extent of acceleration surprised me and in very little time the nose was pitching up and it was time to raise the undercarriage. The nose wheel door served as the speed brakes and there was a transient trim change as it retracted. I instinctively tried to dampen out the trim changes and found to my dismay that I was out of phase. As this was happening the words of the briefing pilot came back to me. "Don't try to follow the trim changes as the gear retracts."
The nose pitched up and down with each pitch more than doubling. Within two seconds I was alternating from a diving attitude towards the runway to a steep climb. Self preservation prompted me to pull the stick hard back holding back pressure. The aircraft damped the oscillations quite rapidly as I zoomed up into the start of a loop. It was easier to relax as I put more space between me and the runway and soon had it all sorted out.
Full fuel load was about 1500 pnds. With the V Bombers, I was used to getting back near the airfield with 10 to 15 thousand pnds minimum. I mentally added a zero to the fuel contents to prevent any preoccupation with the small fuel quantity. I had decided to be back in the circuit with no less than 300 pnds remaining.
I climbed to 45,000 ft over the sea and flew a few dives to go supersonic. The transient trim changes could be readily managed by the new flying tail and I found that any tendency to 'JC' would cease if the grip on the stick was released. This meant that trim had to be maintained with care.
In next to no time, the fuel gauge was insisting that I go back to base. I joined on a long down wind leg and slowed down to drop the gear. There was a large trim change as speed reduced which was readily accommodated by the normal trim. I noted that the nose-up trim remaining was negligible, as I selected gear down. Whoops - now I have the stick against the rear stops and the nose is still going down. Oh yes - I was told to expect this - use the over-ride - that switch down there on the vertical part of the instrument panel. I change hands and grab the switch, instinctively pushing it down. Whoops again - that was the wrong way. Now I am about 20 degrees nose down with the ground coming up too fast for comfort. A quick reversal of the switch and it reverts to being a controllable aircraft again. To me, that switch was operating in the wrong sense.
About this time, the tower called up to say that there was an English Electric Lightning joining the circuit with a company pilot on his first flight into Boscombe and would I give him priority for landing. I did a double take and called the Lightning pilot and asked him for his fuel state. He had over 1000 pnds. I was down to 250 pnds and now somewhat twitchy. The Lightning pilot defused the situation by declining any need for priority as I guided that little Gnat down on to the runway with some feelings of relief, considering the fuel remaining.