The Humbert Tétras (English: Grouse) is a French two seat
ultralight with a single engine and
high wing. Available as a kit or complete aircraft, it has been in production since 1994 by
Humbert Aviation of
Ramonchamp.
Its straight non tapered wing is a
composite structure, with an aluminium frame, Styrofoam filling and
fabric covering.[1][2] The
ailerons and three-position
flaps are made of aluminium. The wings are braced on each side with a single
lift strut to a lower
fuselagelongeron. The
tailplane, mounted at mid-fuselage height, is also strut braced. The fuselage of the Tétras is a steel structure covered with
Dacron. Variants with both
tricycle and
conventionalundercarriages, all fixed, have been built. The former arrangement has spring
cantilever main legs, the latter has the mainwheels mounted on
faired V-strut legs and
bungee sprung half axles fixed to a compression frame. Both undercarriage variants have
hydraulic brakes. Skis may also be fitted.[1]
The Tétras has been fitted with a variety of engines; originally the 54 kW (72 hp) Humbert-Volkswagen HW 2000 was used. More recently two flat fours from the
Rotax range, the 60 kW (80 hp) 912 UL or the 74 kW (98 hp) 912 ULS, have become standard choices.[1]
Operational history
About 150 Tétras appeared on the French ultralight register in October 2010. The French Centre d'Essais en Vol have tested the Tétras for military use, and
Niger has used it for insecticide spraying.[1]
Variants
Data from Jane's All the World's Aircraft 2011/12[1]
Tétras A
Initial version
Tétras B
Standard version, introduced 1998. Early examples had the HW 2000 engine but the 80 hp (60 kW)
Rotax 912UL, or optionally the 100 hp (75 kW)
Rotax 912ULS engine, is currently (2015) fitted. Currently available.[3][4]
Tétras BS
912 ULS engine. Currently available.
Tétras CS
Introduced 2007 with a 600 mm (23.6 in) shorter span wing. 912 ULS engine. Marketed 2008-9.
Tétras CT
Tricycle undercarriage version of CS, with 512 UL engine. Marketed 2008-9.
Niger Air Force – Eight Tétras 912SCMs delivered from France around 2008. One crashed in 2010 and another the following year. As of 2018, three aircraft were in service, with the remaining three stored.[10]
Specifications (Tétras B)
Data from Jane's All the World's Aircraft 2011/12[1]