The Ultra-Efficient Products Invader is an American
ultralight aircraft
Ultralight aviation (called microlight aviation in some countries) is the flying of lightweight, 1- or 2-seat fixed-wing aircraft. Some countries differentiate between weight-shift control and conventional three-axis control aircraft with ailer ...
that was designed by Nick Leighty and Rick Berstling, produced by
Ultra-Efficient Products and introduced in 1982.
[Cliche, Andre: ''Ultralight Aircraft Shopper's Guide'' 8th Edition, page E-19. Cybair Limited Publishing, 2001. ]
Design and development
The Invader was designed to comply with the US
FAR 103 Ultralight Vehicles
Ultralight aircraft in the United States are much smaller and lighter than ultralight aircraft as defined by all other countries.
In the United States, ultralights are described as "ultralight vehicles" and not as aircraft. They are not requ ...
rules, including the category's maximum empty weight of . The aircraft has a standard empty weight of . It features a cantilever
mid-wing, pod-and-boom layout, a
V-tail, a single-seat, open cockpit,
tricycle landing gear and a single engine in
pusher configuration
In an aircraft with a pusher configuration (as opposed to a tractor configuration), the propeller(s) are mounted behind their respective engine(s). Since a pusher propeller is mounted behind the engine, the drive shaft is in compression in nor ...
.
The aircraft has unusual construction. The
fuselage pod is made from
gas tungsten arc welded
aluminum tubing and composite, attached to a partially double-sleeved aluminum irrigation pipe. Its span wing is constructed from wood, with foam
ribs and one third span
aileron
An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...
s. The V-tail is
all-flying and is made from foam ribs glued to the aluminum tubular
spar. The flying surfaces are covered in either
Mylar or
doped aircraft fabric covering
Aircraft fabric covering is a term used for both the material used and the process of covering aircraft open structures. It is also used for reinforcing closed plywood structures. The de Havilland Mosquito is an example of this technique, as ar ...
. On early models the control system is two-axis, all controlled by the
control stick, while later ones incorporate rudder pedals.
The standard powerplant supplied was a
Yamaha engine of which provides the Invader with a cruise speed of , but limits the ceiling to . The very aerodynamically clean design produces a
glide ratio of 14:1.
Operational history
In operational service the aircraft proved to have problems with the ribs deteriorating and separating from the spar after only four years, even when the aircraft was stored indoors. This problem has affected used aircraft prices, as most surviving examples require repairs.
Variants
;Invader Mk II
:
Conventional landing gear model.
;Invader Mk III
:
Tricycle landing gear model.
Specifications (Invader Mk III)
References
{{reflist
External links
Photo of an Invader Mk III
1980s United States ultralight aircraft
Homebuilt aircraft
Single-engined pusher aircraft