The ICA IS-28 is a two-seat
sailplane produced in
Romania in the 1970s. An all-metal
aircraft of conventional design with a T-tail, it was originally produced with 15-metre wings, but in 1973, production shifted to the IS-28B with 17-metre wings and numerous
aerodynamic refinements. These included a smaller tail with decreased dihedral, decreased dihedral on the wings, and redesigned
fuselage contours. This version first flew on 26 April 1973 and was subsequently produced in versions with flaps (IS-28B2) and without (IS-28B1). Around 100 had been built by the early 1980s, with a substantial number sold for export. On April 7, 1979,
Tom Knauff and R. Tawse set a world record with the IS-28 B2 glider, covering a distance of 829 kilometres on a predetermined out-and-return course from the
Ridge Soaring Gliderport in
Julian, Pennsylvania.
The IS-28 was also produced as a
motorglider, initially as just a powered version of the
IS-28B2 (designated the IS-28M1) and then as the more radically redesigned IS-28M2. This version had an entirely new forward fuselage offering side-by-side seating for the two occupants, wings relocated to a low-set position on the fuselage, and tailwheel undercarriage with main units that semi-retracted backwards into the wings. The rear fuselage, empennage, and outer wing panels remained identical with the sailplane version.
The IS-29 is a single-seat sailplane that was designed and manufactured to complement training carried out in the IS-28 two-seater.
The IS-30 is a refined IS-28B2, identical in most respects other than having all-metal control surfaces (where the IS-28 has fabric-covered surfaces) and a re-designed
horizontal stabiliser.
Variants
IS-28M2
IS-28 - sailplane with 15 metre wings
IS-28B
IS-28B1 - sailplane with 17 metre wings and DFS-style
airbrakes
IS-28B2 - similar to IS-28B1 with flaps and Schempp-Hirth-style airbrakes
IS-28M
IS-28M1 (aka IAR-34)- tandem seat motorglider version of IS-28B1 with
Limbach SL.1700E1 engine
IS-28M2 - motor-glider with side-by-side seating and three-point undercarriage
IAR-28M2A - IS-28M2 with new wing, split flaps and
Limbach L.2000E01 engine
IS-30 - all-metal IS-28B2 with new tailplane.
IAR-46 - trainer version of IS-28M2 with reduced wingspan and
Rotax 912A engine
The
Romanian Airclub [
ro] - still using IS-28B2 and IS-29D2 for glider pilots in training and performer pilots. A fleet of 5 IS-28M2 motor-gliders were restored and declared able to fly again.
Specifications (IS-28B2)
Data from Jane's All the World's Aircraft 1988-89[2]