Gossamer Albatross

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The Gossamer Albatross was a human-powered aircraft built by Dr Paul B. MacCready. On June 12, 1979 it completed a successful crossing of the English Channel to win the second Kremer prize.

The aircraft was powered using pedals to drive a large two-bladed propeller. Piloted by amateur cyclist Bryan Allen it completed the 35.8 km crossing in 2 hours and 49 minutes, achieving a top speed of 29 km/h (18 mph) and an average altitude of 1.5 metres.

The aircraft is of unusual configuration, using a large horizontal stabilizer forward in a manner similar to the Wright brothers successful craft. The Gossamer Albatross was constructed using plastic over a carbon fibre frame, with the structure of the wings provided with expanded polystyrene ribs. The entire structure was then wrapped in a thin, transparent plastic (Mylar®). The empty weight of the structure was only 32 kg, although the gross weight for the Channel flight was almost 100 kg. To maintain the craft in the air it was designed with very long tapering wings, like those of a glider, allowing the flight to be undertaken with a minimum of power. In still air the required power was on the order of 0.3 horsepower (200 W), though even mild turbulence made this figure rise rapidly.

Characteristics

Length: 10.36 m

Span: 29.77 m

Height: 4.88 m

The aircraft was designed and built by a team led by Paul B MacCready, a noted US aeronautics engineer, designer, and world soaring champion, and Gossamer Albatross was his second human-powered aircraft. The first was the Gossamer Condor which won the first Kremer prize on August 23, 1977 by completing a specified figure-eight course.

MacCready's team built two Albatrosses; the back-up plane was jointly tested as part of the NASA Langley/Dryden flight research program in 1980. The back-up craft was also flown inside the Houston Astrodome, the first ever controlled indoor flights by a human-powered aircraft. The Albatross II is currently on display at the Museum of Flight in Seattle, Washington. The aircraft used in the channel-crossing is on display at the Smithsonian Institution's Udvar-Hazy center.

A follow-up to the Albatross was the solar-powered Gossamer Penguin in 1980. The "Penguin" airframe had been built by the MacCready team as a third craft for the cross-channel attempt; in most of its dimensions it was 3/4ths the size of the Gossamer Albatross, and was held in reserve as a speedier if slightly higher-powered alternative to be used if it were found that the Channel weather precluded success by the slower-flying Albatross.

The Cheetah

The Dexter Hysol Cheetah is a fully faired semi-recumbent two wheeled Human Powered Vehicle (HPV). The Cheetah currently holds the world speed record for the 200 meter flying start event. This event allows a virtually unlimited run up to a 200 meter speed trap. Chris (The Punisher) Huber rode the Cheetah to an an average speed of 68.73 mph through the speed trap. The record was set at about 6:55 PM mountain standard time on September 22, 1992. The course was on Six Mile Lane which is a flat road which crosses a Bison preserve in the San Luis valley, Colorado. Of course, the Cheetah is named after the fast cat of the same name.

The Cheetah is predominantly constructed of carbon fiber composites with aluminum inserts bonded in with Hysol adhesives. Bicycle components donated by Campagnolo included a tensioned Kevlar rear disk wheel and a generous selection of alloy chainrings and freewheels. Most other components were custom designed and fabricated by the Cheetah Team. The aerodynamic fairing which encloses the rider of the Cheetah is also constructed of carbon fiber composite. Aerodynamic design and advice was provided by Michael Selig (currently an assitant professor of aeronautical engineering at the University of Illinois at Urbana Champagne). The shape of the Cheetah was designed by the Cheetah Team using a custom written Macintosh program. The Cheetah weighs in at 29.5 pounds complete with fairing and ready to ride.

The International Human Powered Vehicle Association (IHPVA) participated in and sanctioned the event. Two IHPVA officials witnessed the event and the timing equipment was provided by the IHPVA. For more information about IHPVA, see their website (http://www.ihpva.org). The format and rules for the 200 meter flying start event were originally proposed by DuPont with a $25,000 price to be awarded to the first HPV to exceed 65 mph. This was accomplished and the prize awarded to the Gold Rush, ridden by Freddie Markham, in 1986 with an average speed of 65.48 mph. The current record of 68.73 mph set by The Cheetah team September 22, 1992 still stands.

On 27 October 1991, Mark Drela pedalled the human-powered hydrofoil, Decavitator, to a world-record speed of 18.5 knots (9.53 meters/second) over a 100 meter race course on the Charles River in Boston, Massachusetts.

In the spring of 1993 the Decavitator team was awarded the DuPont prize for the fastest human-powered water craft. This prize was to be awarded to the first team to break 20 knots over a 100 meter course, or to the team with the fastest speed on record as of 31 December 1992.

A Little Background Information...

The trek to the world record flight began in 1988 as Daedalus team members Marc Schafer and Bryan Sullivan returned from Greece. At that time they decided to build a human-powered vehicle (HPV) that an armchair athlete could operate. Marc initiated a student-run project (under MIT's Undergraduate Research Opportunities Program - UROP) with funding from the MIT SeaGrant program. When the $25 000 DuPont Prize was announced in 1989, the goals of the project changed and speed became the primary objective. For the rest of the story, see the history page.

Where did the name "Decavitator" come from? Traditional boats often encounter problems at high speeds when their propellors cavitate. This boat uses an air propellor, and thus never suffers from cavitation. Also, if you stand too close to the propellor you could lose your head.

AHS Competition

After the successful attempts of fixed wing human powered flights (Gossamer Condor, Daedalus etc.) the American Helicopter Society (AHS) established a competition in 1980, for a Human Powered Helicopter (HPH) flight. The Igor I. Sikorsky Human Powered Helicopter Competition is presently offering $20,000 U.S. for a successful controlled flight of an HPH. Although the competition calls for a one-minute hover and a momentary reach of 3 meters, no one has yet claimed the prize. In recent years there have been 17 HPH's built worldwide (in the United States, Japan and England) but only two have flown. The official world record at present is just under 20 seconds of flight and only inches off the ground.

The Human Powered Helicopter