Farrar LSG-1 Bird Flight Machine
{{Short description|1969 experimental research glider}}
{{Use dmy dates|date=October 2021}}
{{Use American English|date=October 2021}}
| {{Infobox aircraft begin
| name=LSG-1 Bird Flight Machine | image= | caption= }}{{Infobox aircraft type | type=Experimental research glider | national origin=United States | manufacturer= | designer=Demetrius F. Farrar Jr. | first flight= | introduced=1969 | retired= | status=Production completed | primary user=Vanderbilt University | more users= | produced= | number built=one | developed from= | variants with their own articles= }} |
The Farrar LSG-1 Bird Flight Machine is an American, high-wing, V-tailed, single-seat, experimental research glider that was designed and built by Demetrius F. Farrar Jr. in 1969 for exploring aspects of bird flight.{{Cite web|url=http://www.sailplanedirectory.com/PlaneDetails.cfm?planeID=43 |title=Bird Flight Machine Farrar |accessdate=10 August 2011 |last=Activate Media |year=2006 |url-status=dead|archiveurl=https://web.archive.org/web/20070609072252/http://www.sailplanedirectory.com/PlaneDetails.cfm?planeID=43 |archivedate=9 June 2007}}{{Cite web|url = http://registry.faa.gov/aircraftinquiry/NNum_Results.aspx?NNumbertxt=6437|title = Make / Model Inquiry Results N6437|accessdate = 17 August 2019|last = Federal Aviation Administration|date=17 August 2019}}
Design and development
The LSG-1 was specially designed by Farrar for research purposes as part of a Vanderbilt University project into how birds fly and was supported by the US National Science Foundation. The aircraft's design goals included a stall speed of {{convert|20|mph|km/h|0|abbr=on}} and a 60-foot per minute (0.30 m/s) sink rate.
The aircraft is of mixed construction. The fuselage is made from a sandwich of balsa and fiberglass, while the wing is of wood and Kevlar, built on an aluminium spar. Its {{convert|61|ft|m|1|abbr=on}} span wing employs an unusual Wortmann FX 05-H-126 airfoil, which was originally designed for helicopter use. This airfoil section was chosen because it has zero pitching moment, which thus allows moderate torsional loads despite the resulting glider's relatively large wing area of {{convert|230|sqft|m2|abbr=on}}. The LSG-1 has no glidepath control devices, such as dive brakes, making it a challenge to land. Despite its large wingspan the aircraft has a very low empty weight of {{convert|181|lb|kg|0|abbr=on}}, giving it a very low wing loading of 1.55 lb/sq ft (7.6 kg/m2).{{Cite web|url = http://www.ae.illinois.edu/m-selig/ads/aircraft.html|title = The Incomplete Guide to Airfoil Usage|accessdate = 1 August 2011|last = Lednicer|first = David|authorlink = |year = 2010|archive-url = https://web.archive.org/web/20100420012244/http://www.ae.illinois.edu/m-selig/ads/aircraft.html|archive-date = 20 April 2010|url-status=dead}}
Only one LSG-1 was built and it was registered with the US Federal Aviation Administration in the Experimental - Amateur-built category.
Operational history
The aircraft was used to explore bird exploitation of microlift under supervision of Gary Osoba. In August 2011, 42 years after it was completed, the aircraft was still on the FAA aircraft register and still owned by the designer. Its registration expired and was cancelled on 29 April 2013 and it is unknown if the aircraft still exists or not.
Operators
Specifications (LSG-1)
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