MIT BURD

{{Short description|1970s United States human-powered aircraft}}

{{DISPLAYTITLE:MIT BURD}}

{{Use mdy dates|date=April 2023}}

{{Use American English|date=April 2023}}

{{Infobox aircraft begin

|name =MIT BURD

|image =

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{{Infobox aircraft type

|type = Human-powered aircraft

|national origin =United States

|manufacturer =Massachusetts Institute of Technology

|designer =Paul Hooper

|first flight =

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|number built =1

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|developed into =MIT BURD II

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The BURD was a two-place human-powered biplane, designed and built by graduates and undergraduates of the Massachusetts Institute of Technology, with Professors Eugene Covert and James Mar acting as project advisers. It was developed with the specific goal of winning the £50,000 Kremer prize then on offer.

BURD is an acronym for "Biplane Ultralight Research Device", reflecting the aircraft's configuration. The project was notable for it involving computational analysis as well as wind-tunnel tests of a scale model. The two-person option was adopted, as that allowed for a better power-to-weight ratio. The canard configuration was selected due that giving a beneficial increase in lift. The biplane configuration, fitted with endplates, was adopted due to the aerodynamic and structural benefits from using that arrangement.

The primary structure for the fuselage was made from aluminum tubing, while the primary structure for the flying surfaces were box-beam spars made from sheet balsa. The secondary structure was made primarily from balsa, with aluminum tubing and sheets used in high-stress areas. The entire airframe was covered in transparent film. The undercarriage consisted of two bicycle wheels, arranged in tandem. As originally built, the front wheel was fixed, and not able to be steered. The two-person crew sat in a tandem arrangement, and powered a chain drive which connected to both the rear undercarriage wheel and the rear-mounted pusher propeller. Pitch control was to be achieved by pivoting the foreplane in its entirety. Lateral and directional control was to be attained by spoilers mounted on the lower wing, with the spoilers producing a yawing force in the direction of the turn that the aircraft was being banked towards. In addition, a vertical fin was located above the upper wing.

The BURD was completed in May 1973. Taxiing tests conducted at Hanscom Field airport in Bedford, Massachusetts, revealed significant design and construction issues. Alterations were made to the undercarriage, the drive system, and to the controls for both the foreplane and the spoilers. In 1975, the first flight attempt took place, but ended with an almost complete structural collapse of the aircraft.

In 1976, a new iteration of the design, named the MIT BURD II, was built, with this craft incorporating a number of detail changes from the original.

Specifications

{{Aircraft specs|ref=The M.I.T. Man-Powered Aircraft and Man-powered aircraft

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|crew=2

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|length ft=27

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|wing area sqft=640

|wing area note=plus 60 sq ft (5.60 m2) canard wing area

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|airfoil=Wortmann FX61-163

|empty weight kg=

|empty weight lb=128

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|gross weight lb=400

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|eng1 number=2

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}}

See also

References

{{reflist|refs=

{{cite book |last=Dorsey |first=Gary|date=1990 |title=The Fullness of Wings: The Making Of A New Daedalus |location=New York, NY |publisher=Viking |pages=40–47 |isbn=0670824445}}

{{cite book |last=Dwiggins |first=Don |author-link=Don Dwiggins |date=1977 |title=Man-powered aircraft |location=Blue Ridge Summit, PA |publisher=Tab Books |pages=165–167 |isbn=0830622543}}

{{cite book |editor-last1=Taylor |editor-first1=John W. R. |date=1976 |title=Jane's all the world's aircraft 1976-77 |location=London |publisher=Macdonald and Jane's Publishers Ltd |pages=521–522|isbn=0354005383|url=https://archive.org/details/janesallworldsai0000unse_a7n3/page/522/mode/2up|access-date=April 9, 2023}}

{{cite magazine|last1=Wahl |first1=Paul|date=February 1974|title=Who Will Take Aviation's Richest Prize?|magazine=Popular Science |location=New York, NY| publisher=Times Mirror Magazines, Inc, Inc|volume=204 |number=2|pages=90–92, 136–137 |issn=0148-7191 |url=https://books.google.com/books?id=VWTF3my04Q0C&dq=who%20will%20take%20aviation's%20richest%20prize%3F&pg=PA90 |access-date=9 April 2023}}

{{cite book |last=Reay |first=D.A. |date=1977 |title=The history of man-powered flight |location=Oxford, England |publisher=Pergamon Press Ltd |pages=296–298 |isbn=0080217389}}

{{cite magazine|last=Hooper |first=Paul| date=1974| title=The M.I.T. Man-Powered Aircraft|magazine=SAE Technical Paper 740392 |location=New York, NY| publisher=Society of Automotive Engineers, Inc|issn=0148-7191}}

}

}}

Category:1970s United States experimental aircraft

Category:Aircraft with fixed bicycle landing gear

Category:Biplanes

Category:Biplanes with negative stagger

Category:Canard aircraft

Category:Human-powered aircraft

Category:MIT aircraft

Category:Pusher aircraft

Category:Twin-engined single-prop pusher aircraft

Category:Unflown aircraft