FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1979
1979 - 1799.PDF
» FLIGHT International, 26 May 1979 Man-powered challengers are confident DR PAUL MacCREADY, designer of the Gossamer Albatross man-powered aircraft, pilot Bryan Allen and a faithful band of about eight sup porters are totally confident in their ability to fly the English Channel under man-power. They arrived in the UK earlier this month, having been flown across with materials for three aircraft in an RAF Hercules. The existing airworthy example has been flying for a few months now, and although it started life weighing 551b (25kg), repairs and modifications have added about 151b (6-8kg). A flight of more than 13 miles was made last month (see Flight last week) and as such the airframe has proved capable of sustained long-distance flying. Gossamer Albatross uses the same configuration as the earlier Gossamer Condor, but in every respect it is a new aeroplane. "Gossamer Condor could have been built 50 years ago, but the Gossamer Albatross uses modern-day technology," claims Mac- Cready. His aircraft has some alumin ium fuselage frames but uses carbon- fibre tubes for the wing mainspar and bowsprit. The propeller is made from sections of shaped polystyrene with a Kevlar outer surface. MacCready says that it will be lighter and made with a carbon-fibre surface if he has to produce another version, although the existing unit weighs only 31b (l-4kg) and has a propulsive effici ency in the order of 88 per cent. Power-transmission efficiency has been improved also by using a urethane chain between the pedals and propel ler drive-shaft. The pilot will have a radio link with the ground and has electronic airspeed and height sensors. The lat ter is a classic example of the ingenuity now expected of MacCready: it uses an auto-focus sensor from a commercial Polaroid camera and with battery power can function efficiently for several hours throughout the height band in which the aircraft operates. Bryan Allen, or back-up pilot Kirke Giboney, needs only to produce 0-25hp for about 2hr to com plete a Channel-crossing. He will have 21it of water to keep thirst at bay. MacCready's only real concern is overheating, the transparent gondola having proved to be hot and un comfortable in direct sunlight, so he has brought aluminised Mylar skin material to cover the second aircraft's gondola. If the pilot does tire the aircraft can be hooked on a fishing line and towed home at 12kt by a boat. Allen says that during trials he has flown the Gossamer Albatross at less than 8kt, but control is sluggish. He usually cruises at llkt and found it tiring trying to sustain 14kt. These speeds and a maximum altitude of 30ft—as much to ensure safety as to keep in ground effect—will allow the aircraft to bypass shipping. A radar- equipped boat will be part of the flotilla accompanying the aircraft. Large tankers are rare in the Channel, says MacCready, but if one does ap pear he is happy that the pilot should turn parallel to the ship's track and pass behind its wake. His biggest worry is other aircraft, and he wants no aeroplane or helicopters within miles of the man-powered aircraft. Sightseers are therefore urged to en joy a boat ride rather than to try accompanying the aircraft. Turbulent wake from an aircraft over half a mile from Gossamer Condor was sufficient to cause a mainspar failure. Weather is the only ingredient needed for success, according to the team, and statistically the coming four weeks should provide plenty of opportunities. MacCready favours tak ing off from a make-shift plywood runway north-east of Folkstone, prob ably at 4 a.m., when the air is calm, sea traffic is at a minimum and the pilot does not have to endure strong sunlight. If June fails to provide a good opportunity, or if the first attempt terminates in a broken air frame, the team is prepared to stay as late as September. MacCready feels quite positively that it is only a matter of "when." The bid will have cost him around the £100,000 that he can ex pect to win from industrialist Henry Kremer if he succeeds with the first man-powered Channel crossing. Pilot Bryan Allen and designer Dr Paul MacCready stand by the gondola of Gossamer Albatross in London last week Solar-powered aircraft take to the air TWO teams, one in Britain and one in America, are claiming that they were first to fly a solar-powered air craft. Larry Mauro flew a converted Easy-Riser hang-glider, called Solar Solar One, the UK's first solar-powered air craft, was equipped with three electric motors when this photograph was taken. Four motors were however used when the aircraft first flew on December 19 last year. Riser, from Fla-Bob Airport, River side, Calif, in late April using power generated from about 60O solar cells on the aircraft's upper wing. An elec tric motor driving a single propeller took the aircraft half a mile at up to 40ft altitude. His claim to being first solar- powered flier is challenged by Fred To and David Williams in Britain. They have been building a solar-powered aircraft for almost two years and, during trials on December 19 last year, David Williams flew the aircraft for 10-20yd at less than 2ft altitude. The flight was made on a cold day when the airframe was covered with frost, and up a slope of about 1:60 at Lasham, Hants. Two witnesses who support the claim are Patrick Wright and Lasham chief flying instructor Derek Piggott. A further flight was to have been made when there was no frost and with a more favourable wind direction but, after one of four 1 h.p. Bosch units was damaged, the delivery of a replacement was de layed by a customs dispute in the UK. A motor was obtained three weeks ago and the aircraft is ex pected to fly very soon—weather per mitting. The UK aircraft, called Solar One, was designed by Williams to British Gliding Association requirements. It has been successfully towed to more than 50ft on several occasions, but for solar-powered flight 750 solar cells, capable of generating 350w, are attached to the wing centre section. The wingspan is 68ft and wing area is 260 sq ft. A 7 • 5ft-diameter glass-fibre propeller has been superseded by a 5 • 25ft-diameter wooden propeller which runs at about 1,100 r.p.m. Cruising speed is about 25kt, and the aircraft weighs 2301b. During its flight it carried a 1751b pilot.
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
