| FMX-4 Facetmobile | |
|---|---|
| The FMX-4 Facetmobile in flight | |
| Role | Homebuilt Aircraft |
| National origin | United States of America |
| Designer | Barnaby Wainfan, Lynne Wainfan, Rick Dean |
| First flight | 22 April 1991 |
| Number built | 1 |
The Facetmobile (properly, FMX-4 Facetmobile) is a homebuilt aircraft designed by Barnaby Wainfan, a NACA aerodynamicist and homebuilt aircraft engineer.
While only one Facetmobile prototype was produced, it has become well known due to its unique nature.[1] The aircraft is something of a cross between a lifting body and flying wing configuration - the whole aircraft is one low aspect ratio wing: a flat, angular lifting shape. Particularly notable is that the aircraft's shape is formed of a series of 11 flat surfaces, somewhat similar to the body of the F-117 Nighthawk jet strike aircraft, but without separate wing structures. The Facetmobile was designed prior to the public disclosure of the F-117 aircraft shape, and Wainfan claims that the visual similarity is coincidental, with very different engineering reasons (the F-117 uses flat panels for stealth technology, the Facetmobile for ease of construction). [2]
Contents |
The Facetmobile is a unique design in many ways. [2] [3]
As noted above, the Facetmobile is a unique airfoil shape, but is generally similar to some other generally low-aspect-ratio delta-wing light aircraft, such as the Dyke Delta models JD1 and JD2, the Hatfield LB1 and LB3, and the ARUP 2.
The FMX-4 Facetmobile shape forms 11 flat planes, plus two wingtip rudders. Three flat shapes form the bottom of the aircraft (slightly inclined front, flat middle, and sharply raised back), and eight form the top (one large downwards-sloping rear section, one thin nose section, and three inclined side panels per side). The wing section is an 18% thickness ratio, much thicker than the typical 12-15% thickness of normal light aircraft wings. At least one commercial model airplane kit of the Facetmobile is in production. [4]
The Facetmobile structure is composed of 6061 aluminum tubing fastened with Cherrymax rivets. The fuselage uses conventional fabric covering. The aircraft uses elevons and rudders for control. The landing gear is a fixed tricycle type. The large windshield sections are augmented by two floor-mounted windows. The aircraft is boarded through a bottom-mounted hatch. The aircraft has a BRS parachute system installed.
Data from Sport Avaition
General characteristics
Performance
The prototype FMX-4 Facetmobile crashed on October 13, 1995, after an in-flight engine failure. The aircraft landed at low speed into a barbed wire fence, which caused extensive skin, engine, and some structural damage, though there was no injury to the pilot (Barnaby Wainfan). [5] As of 2006, the aircraft has been partially repaired but not flown again.
Wainfan has proposed two derivative aircraft based on the FMX-4 Facetmobile.