Flying the Nimrod

Air Classics, Sep 2003 by Brown, Charlie

NO PILOT'S NOTES SURVIVE FOR THE HAWKER NIMROD SHIPBORNE FIGHTER, SO THE AUTHOR FACED A TRICKY TASK WHEN FLIGHT-TESTING THE SOLE AIRWORTHY EXAMPLE

Shortly after becoming chief pilot for the Historic Aircraft Collection (HAC), I was asked if I would flight-test the collection's Hawker Nimrod Mk. I S1581/G-BWWK when it was completed. Having seen and heard snippets of information regarding the exceptional quality of the restoration, I accepted the offer gratefully. Over the next three years I maintained a listening watch as the work progressed through the many and various technical problems that inevitably accompany such a unique project. As the aircraft neared completion I became more and more closely involved with Aero Vintage, the company responsible for restoration of the airframe and overall project management.

When the time came for the first engine runs I became acquainted with Vintech, the company that had restored the Rolls-Royce Kestrel engine. As well as getting involved with the practical aspects, I tried to accumulate as much theoretical knowledge regarding the airframe and engine as I could muster, so that I would be as well prepared as possible for the flight test.

Theoretical knowledge of flying the Hawker Nimrod was extremely thin on the ground, as was information regarding the many technical aspects of the aircraft's restoration. All of my information was obtained through Guy Black, director of HAC and managing director of Aero Vintage, who extracted and pieced together the information from obscure references in original flight-test reports and suchlike. There were no Pilot's Notes or any equivalent document. I decided that the best plan for preparing myself to fly the aircraft was to gain as much knowledge about the engine and aircraft systems as possible and then fly the aircraft, allowing the aircraft to teach me how to fly it.

In the meantime, RAF Henlow in Bedfordshire was selected as the location for the final erection and initial flight testing. By kind permission of the RAF, Aero Vintage and Vintech personnel were allowed access to the station, hangarage was arranged and the aircraft was allowed to fly from the aerodrome. As soon as it was ready to be taxied I completed taxiing tests. For me, these tests are a vital part of preparing for a first flight, as so much useful information is gained: Assessing the harness system, operation of the wireless, view from the cockpit, the ride of the aircraft, efficiency of the brakes, etc. In the Nimrod, the seat height is adjustable by means of a handbrake-type lever on the right-hand side of the seat, and with the seat in the highest position I found that the view from the cockpit was actually much better than I expected. The original Palmer toe brakes were adequate for maneuvering on the ground. Directional control was easy, and the aircraft felt well-bal-anced and sure-footed even in the 15-kt wind that was blowing at the time.

Further engine runs and fine-tuning followed under the guidance and direct supervision of Vintech. When all interested parties agreed that there was no more to be done, the aircraft was signed off as ready for its first flight in 62 years.

AIRBORNE

There was a good turn-out for the first flight, on 11 July 2000. It was attended by most of the staff from Aero Vintage, a fair number of personnel from RAF Henlow, members of HAC and Guy Black, who originally obtained the remains of the air-craft and had led the restoration from the outset. The weather was just about perfect. The wind was steady at 10-kt, just about straight down Henlow's runway 02, and the odd puffy cumulus cloud was sculling around in the clear blue sky.

Start-up and taxi were uneventful. With the testing of the engine and pre-takeoff checks complete, I lined up on the runway, taking care to ensure that the aircraft was absolutely straight, and took a mental picture of the aircraft's attitude and the appearance and proportions of the runway. This was the picture that I would have to reproduce to make a perfect three-point landing. As I opened the throttle my attention was focused outside the aircraft. When I felt the elevators come alive, I smoothly and cautiously raised the tail, maintaining a tail-down attitude, noted the airspeed increasing, the boost at 3-lb/sq-in (takeoff limit 6-lb), rpm well within limits and the aircraft accelerating strongly. It flew itself off the ground at 50-mph estimated (the first graduation on the airspeed indicator is 60-mph).

Once airborne, I held the takeoff attitude as the aircraft accelerated, and checked engine temperatures and pressures, which were all well within limits. Setting the boost at the climb setting of 15-lb/sq-in, I established the climbing attitude for the climbing speed of 115-mph. The Nimrod was climbing like a lift in a remarkably nose-low attitude. In short order I was at 3400-ft (as high as I could climb below Luton controlled airspace) in the Henlow overhead. I set -0.25-lb/sq-in boost, the maximum cruise setting, noting that the airspeed stabilized at 150-mph and that it was getting a bit breezy around my head. Lowering the seat two notches, I found I was much more comfortable but still had a very good view out of the cockpit. After watching the engine temperatures and pressures for 5-min, and having established that the engine was behaving itself, I set about investigating the Nimrod's stalling characteristics.