LOCKDOWN SPECIAL

A happy LAA test pilot Dan Griffi th, with Peter Kember (standing).

A lockdown special…

The completion and test fl ying of HAPI SF-2A Cygnet G-CYGI was 30 years in the making, as Peter Kember reports…

he period of the Government imposed

T‘lockdown’ during the Covid-19 pandemic from March 2020 has produced some interesting and widely varying individual responses. In my case I found myself walking and cycling with my wife Marion on local roads and pathways which were free of traffi c, discovering parts of the local countryside that I didn’t know existed, and with time to consider the future, however long I might have. Sometimes Marion and I would ‘socially distance’ with similarly retired friends on longer walks – an excuse for eating copious quantities of homemade snacks and supping warm glühwein from our fl asks.

Marion has also developed her artistic and teaching skills with mostly animal drawings and paintings, and I have restored two 40-year-old Honda motorcycles, one of which I sold, and the other which I regularly use on trips to local airfi elds. I also bought a powerful Ducati Scrambler which has acceleration I fi nd disturbing, so that may have to go! I still fl y the second of the two Europas that I have built, courtesy of the present owners, which I maintain and inspect for its annual permit renewal. But I needed another, more absorbing project which would attract me into my single car garage/workshop – fortunately adjoined to the house and centrally heated. Although in my fl ying life I have owned a number of different aeroplanes, including a Piper PA22 Tri-Pacer, a Grumman AA5, and a Jodel DR1051 Sicile Record, my greatest enjoyment has come from the two Europa kits that

I have built. In 1995, G-OPJK was the first Mono to fly, and in 2005 the second was the so-called kit number 1000, Europa XS HiTop, G-TOPK. The project that I was looking at turned out to be the completion of part-built Cygnet G-GYGI, which took me over 800 hours of work before its first flight in the summer of 2021. The first flight of a homebuilt light aeroplane is a special occasion for those involved in its construction. The first flight of a plans-built aeroplane is even more special at a time in aviation history when kit-built and factory aircraft predominate. For the homebuilder, witnessing the first flight is, for me, akin to the birth and first few days in the life of a child, will it be safe, and will it survive the rigours of life? And so it was that Cygnet G-CYGI first took to the skies at Laddingford Aerodrome in Kent on 21 July 2021, in the capable hands of Carl Meek from East Sussex, after 30 years in the making. In 1991, a Rolls-Royce trained design engineer, Barry Brown, had commenced construction of the Cygnet from the HAPI supplied plan set number 210. At the PFA Rally at Wroughton in July 1992, Barry had been awarded a PFA Commendation Certificate for his part-completed scratch built aeroplane, then known as the Sisler Cygnet. In the USA in the 1970s, Bert Sisler had designed a short-field, two place aircraft, the fuselage and empennage constructed of 4130 steel tubing, the geodetic braced wings of spruce, all fabric covered and powered by a converted VW engine. There are six Cygnets on the UK Register, some with Rotax 912 stroke engines, although many more are flying worldwide. Sadly Barry Brown was not able to complete his Cygnet as he has developed a debilitating illness and is currently in a care home. The incomplete aeroplane was advertised in Light Aviation magazine in 2020 and I inspected it with my good friend Paul Matthews, a fellow Europa flyer, in December 2020 at Enstone Airfield, Oxfordshire, where it had been stored for some considerable time.

Empennage

Ben Syson, from the LAA, kindly met me at Enstone to show me the wings and the fuselage which was stuffed with small parts, including the empennage. Paul and I recognised that the build quality was exceptional, although it was clear that there remained a considerable amount of work to complete the aircraft. I made an offer, which was accepted by Barry’s wife, and the aircraft was delivered to my home in East Sussex, care of Paul Ponsonby, the aircraft transportation specialist, a couple of weeks before Christmas 2020. Another Europa friend, Ben Mackay, travelled up from the south coast to help me insert the Cygnet fuselage into my home workshop and the wings, tailplane and rudder into my old bike store. After examining the aircraft documents, it was evident that the Rotax 912 had been purchased in 1991 but had never been run. I offered work experience to a young, recently graduated aeronautical engineer, Alex Mills and, on my behalf, he delivered the engine to Kevin Dilks (Special Air Services) in Leicester for Kevin to thoroughly check and Above left Early December 2020 and Paul Matthews and my first viewing of the Cygnet at Enstone Airfield.

Above right The fuselage in my workshop, not much room to spare!

Bottom left The new panel and throttle assembly under construction.

Bottom right A trial fit of the cowlings.

bring it up to the current specification. He did an excellent job at a relatively low cost. The Dacron covered wings, tailplane, elevators and rudder were found to be complete, although the fin had two punctures in the fabric, which were quickly repaired using Ceconite supplied by LAS, a company I was to get to know very well. Given my almost daily call for parts, the staff were exceptionally tolerant. The LAA requires the Cygnet to have a fireproof engine bulkhead and an audible stall warner. Fortunately, Barry had installed a stainless-steel bulkhead but my attempts to find a stall warner at a reasonable price proved fruitless. However, my Inspector on the project, and yet another Europa friend, David Watts, came to my aid by building the required part.

Instrument panel

Early on in the project, and partly to save weight, I decided to remove the engine vacuum pump and the beautifully constructed and very full instrument panel, in favour of lightweight modern electronic and digital devices. The old transceiver and transponder were sold to a buyer in the USA and the remaining instruments have been, and are being, advertised on a well-known auction site. A Kanardia Horis AHRS, and Funke transceiver and transponder were ordered from LX Avionics at Turweston and the GRT Avionics EIS came from the USA, after a delay caused unavailability of parts due to both Brexit and the pandemic. I made a simple flat aluminium panel, and rubber mounted it like I had with the Europas. I experienced some difficulty getting the hydraulic brake system and park brake valve to work, not helped by Matco in the USA supplying me with two master cylinder repair kits and a new park brake valve which they knew would be incompatible. After finding that the brakes would lock on, Matco then informed me the master cylinders should have been modified at some additional cost by fitting a small spring. Marion, meanwhile, took a day or two off from her art and made some very nice seat cushions which proved to be very comfortable, especially on the two-hour endurance test flight. On the 20 April 2021, and much to the chagrin of my neighbours, I rolled the completed fuselage out of my workshop, chocked it and started the engine. It ran very smoothly with good oil pressure, albeit that the temperatures were very slow to climb. On 1 May 2021, using his Europa trailer, Paul Matthews towed the Cygnet to Laddingford Aerodrome, closely followed by Alex and I in our cars to keep other drivers from running into the convoy. This is where the serious work of fitting and adjusting the wings and tailplane occurred. The so called ‘Quick Wing Fold Mechanism’ was found to be almost impossible to operate, the ‘cuddle plates’ which connect the aileron control cables (one in the wing and one in the fuselage) were found to need a considerable amount of adjustment to produce satisfactory aileron responses (nowhere near as good as the Europa mechanism). The braking system was found to snatch because of corrosion on the 30-year-old discs and later, in taxi trials, the park brake valve was found to seize one or other of the brake callipers, which made for some very tight turns. With Matco’s help, the problem was alleviated by modifying the brake master cylinders. After all the normal jobs were complete, in Ivan Shaw’s words there was ‘no reason not to commit aviation’. In a temperature of 26°, Carl took off for the first flight from Runway 11 at Laddingford. He was airborne in about 150 metres and the Cygnet climbed away at over 800 fpm and landed after a totally uneventful half-hour flight. Well, that is not completely true, the AHRS needed calibration, the mode S transponder should have had the input of its unique Hex code, and the MAC electric trimmer needed adjustment for more down force on approach. However, the really important factors like oil pressure and temperature, coolant temperature, cylinder head temperature, electrical charge rate and control harmony were all well within limits. In a one hour second flight that day, Carl recorded all of the essential readings from the EIS, the AHRS and the ASI. Carl also explored the envelope a little further and carried out a power off stall at 37kt, a comfortable cruise of 95kt at 4,800rpm and he easily reached the VNE of 117kt. My eldest grandson, 11-year-old Mylo, was with me for a few days and was one of several people who recorded a video of the first flight on his smartphone. Because of runway flooding at Laddingford and after a short dry spell, on 4 August Carl ferried the Cygnet to Kittyhawk Aerodrome in East Sussex, with me flying chase in the Europa. Two days later and loaded to MTOM, Carl carried out the second series of tests which revealed a rate of climb of 600 fpm and all other readings as before. Although I have over 800 hours on taildraggers and a total of 2,500 hours P1, I had not flown a tailwheel aircraft for about 10 years, which is why I approached my first flight in the Cygnet with a degree of trepidation. It was dreadful! I was overcontrolling, not using the rudder to initiate turns, flying flat out and I even tried to line up for final approach at or near VNE. Carl was cool and quickly told me that I was not flying a Europa! The next day I inadvertently went solo while trying out some fast taxying on Kittyhawk’s Runway 16. Instantly I remembered to drop my shoulders, to relax and to enjoy this strange aeroplane with its superb visibility, excellent ground handling, powerful rudder, and benign pitch controls. I made one of my rare good landings after a trickle of power at 60kt on short final. The very next day I decided to carry out the two-hour endurance test flight and to reach a total of 15 take-offs (and landings!), even managing to drop into nearby Deanland Airfield.

Kittyhawk Airfield

On the 24 September, and in a feast of flying new types, the LAA’s Chief Test Pilot, Dan Griffith, flew the Cygnet from Kittyhawk Airfield. In somewhat difficult turbulent conditions, he came back beaming from ear to ear. He said the aeroplane handled very well, with power on (3,850rpm) he stalled it at 30kt and with power off he stalled it at 35kt, both lower figures than found with other Cygnets in the UK. He said that in level flight, gusts which lifted one wing could easily be corrected by the rudder which, on the Cygnet, is a lighter control than the ailerons. But mostly he eulogised over the climb and descent visibility, which he said compared with the Harriers which he had flown and meant that you could see all the way down to the numbers at the threshold of the runway. A perfect aeroplane for short strips then. After some fine tuning and fettling, including the replacement of the altimeter with a better one bought this year at the LAA Rally Flea Market, and attachment of plastic trim strips to the rudder and starboard elevator, I am now comfortable with the Cygnet. What are its virtues? Excellent ground handling with

superb brakes, good short field capabilities, easy access to and starting of the engine, a significant climb rate, docile handling providing one remembers to lead turns with appropriate rudder inputs, and a good cruise speed at 95kt using under 13 litres of unleaded (preferably ethanol free) mogas per hour. What are its peculiarities? Its looks don’t suit everybody, it much prefers on the ground to turn right rather than left (I need to look again at the Maule tailwheel breakout spring), its tight cockpit and lack of storage space (although it does have a map locker and a 50lb maximum weight storage container behind the seats) and its limited payload of 366lb. I have to admit that returning to a tailwheel aircraft in my 70s does concentrate the mind, but I am sure it is making me a better pilot. You never stop learning, and now I suppose I am a compulsive aircraft builder. But I love it! I would like to thank those who have helped or supported me during the build and test flying, including my wife Marion, Paul Matthews, Ben Mackay, Ivan Shaw, Bobca Lee, Alex Mills, Adam Mills, Carl Meek, Dan Griffith, Dave Watts, Stephen Hall, Sarah Gulzar and, from the LAA, Steve Slater, Francis Donaldson, Ben Syson and Jon Viner. ■ Above I am grateful to Kittyhawk Aerodrome’s Oliver Steel who has provided me with excellent hangarage facilities for the Cygnet at Kittyhawk Airfield.

Above left First

flight on 21 July 2021, with Carl Meek at Laddingford.

Below The updated and lighter panel.