Screwjack Letter No 26

The ‘Air Rider’ Hover Craft, the new project

At the end of my job in Osnabruck, Gill was expecting our second Daughter Katheryn so she went home to her parents a few weeks early. When I packed up our things I realised that our new washing machine was too heavy for an MFO box, so I took out the front left seat out of our Beetle and put it in the MFO box. Then I put the washing machine in the Beetle. It was a tight fit. I had grown some magnificent Dahlias in the garden at Osnabruck so I filled the washing machine with Dahlia tubers, and drove back to UK via Ostende with no problems.

Having done my works training at Westland Aircraft, AG 21 invited me to re-train as an Aircraft Engineer. I accepted, and attended the Officers Long Aeronautical Engineering course at AETW Middle Wallop, with a period at the Royal Navy Engineering College (RNEC) at Manadon, Plymouth. The RNEC trained Ships Engineers as well as Aircraft Engineers. This was fortunate for us all, because at the end of the working day the hot water and steam from the steam turbine laboratory was used to heat the outdoor swimming pool nearby. Midnight swimming in Summer after an evening in the Plymouth Sailing School Club was most enjoyable.

There were ten of us on the course. First thing in the morning we had to attend a parade, Navy style, where we were a ‘Division’. We were all called to attention with the order “Divisions, Ho !” We hoed, as you would. I can remember one formal dinner night at the College, where we all in our mess kit. It all went much as in an Army mess, until a sharp voice called “Hi Gang!” The thunderous response from several hundred voices was “Hi, Wishy-Washy!” I expect this was another Royal Navy tradition; like saluting at nothing when you step aboard a ship. Or else a recent pantomime in Plymouth?

The course continued at Middle Wallop including practical work on Scout, Sioux and Beaver aircraft. During this time came the first Moon landing. It was shown as it happened on television. I woke my five year old Daughter Jackie in the night to let her see and remember it. We also had a few days at Lee on Solent with the Fleet Air Arm where our next postings were notified and read out to us by an RN officer. For some reason mine amused him. It was to the REME Apprentices College at Arborfield.

At the College I took over the Aircraft Apprentices’ training wing from Major Bill Eames. Almost the entire College was in wooden huts. The Officers Mess accommodation was an H block, but I had a very pleasant married quarter. The Aircraft Wing was already wellestablished with ASM Gordon Fielder, five Civilian Instructors, a Secretary and a Storeman. There was also a cleaning lady called Mrs Dragon. I was also invited to undertake responsibility for one of the spare-time apprentice activities. I discovered that SSgt Anderson was building a small hovercraft and he wanted to be rid of it. The Hovercraft was the ‘Air Rider’ design promoted by the Daily Express. Anderson had already built the hull and obtained three Villiers 197 engines, two Permali propellors, and the duct and fan for the lift engine. He said that he now realised that the design was so bad that he contemplated setting fire to it outside the offices of the Daily Express. I knew nothing about hovercraft but this seemed my cup of tea, and I took over the project. I advertised for a few volunteers in Part One Orders and we worked in the evenings for several months. The Villiers engines each had built-in starter-dynamos which were permanently engaged with the engines and thus became dynamos, if required, once the engines started. Lift was to be provided by a fan bolted to one Villiers in the duct. This was set at constant speed when operating the craft, so I charged the battery from the lift engine. Thrust came from the other two engines mounted high at the rear to which we bolted the Permali propellors with outrigger bearings to try to counter gyro forces when turning. We made four rudders in hardboard which were steered in unison with bike handlebars by the driver. At each end of the handlebars I fitted throttle twist-grips to allow the driver to augment rudder steering with differential propellor speeds. The twist grips operated the sliders in the Amal carburettors via two cables each running in a single wide curve over the driver’s head. I decided to fit a short flexible skirt rather than an inflating cushion.

The great day came for a first trial run. I had the good sense to tell nobody other than my three helpers. I started the lift engine and we pushed the Air Rider onto the playing field, in a shower of dust and grass clippings. It just tipped on one side and the lift air spilled to the other side. It seemed top-heavy, somehow. There was a pile of bricks nearby, so we lined the floor with them. The craft now hovered level. I climbed in, started the thrust engines and drove it across the field with no problems. The noise was deafening, but gratifying. I turned around gently, mindful of the gyro force strain on the thrust engines’ crankshafts and drove back across the field. I invited Apprentice Burton to have a go. I forgot to tell him to turn gently. Burton went fast across the field but attempted a flying turn. One of the thrust engine crankshafts broke. The engine still ran but its propellor was stationary. It was the ‘Back to the Drawing Board’ moment. Staff Anderson was right. The craft needed a lower centre of gravity and a wider base. The hull does not need to be shaped like a boat. A single, bigger thrust propellor, belt driven from a lower-mounted engine would probably be better. I should have stuck with oil-drum rafts.

Briefing A/SSgt Dodds