ICA IS-28

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-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

Operators

 Romania

• Romanian Air Force - received 10 IAR-28MA from 1984.^[1]

Specifications (IS-28B2)

Data from Jane's All the World's Aircraft 1988-89^[2]

General characteristics

• Crew: 2
• Length: 8.45 m (27 ft 9 in)
• Wingspan: 17 m (55 ft 9 in)
• Height: 1.87 m (6 ft 2 in)
• Wing area: 18.24 m² (196.3 sq ft)
• Aspect ratio: 15.8
• Airfoil: root:Wortmann FX-61-163; Wortmann FX-61-126
• Empty weight: 375 kg (827 lb)
• Max takeoff weight: 590 kg (1,301 lb) dual

Performance

• Stall speed: 65 km/h (40 mph; 35 kn) dual
• Never exceed speed: 230 km/h (143 mph; 124 kn) dual, in smooth air

• Max rough air speed: 165 km/h (89 kn; 103 mph)

• Max aero-tow speed: 140 km/h (76 kn; 87 mph)

• Max winch-launch speed: 125 km/h (67 kn; 78 mph)
• g limits: +5.3 -2.65
• Maximum glide ratio: 34

• Best glide speed: 100 km/h (54 kn; 62 mph) (dual)
• Rate of sink: 0.86 m/s (169 ft/min)

• Minimum sink speed: 85 km/h (46 kn; 53 mph) (dual)
• Wing loading: 32.34 kg/m² (6.62 lb/sq ft) dual

References

Further reading

• Barnett, Cliff (20 November 1982). "IS-30: Romania's smooth two-seater". Flight International. pp. 1484–85. Retrieved 2008-05-07. 
• Coates, Andrew (1978). Jane's World Sailplanes and Motor Gliders. London: MacDonald and Jane's. p. 124. ISBN 0-354-01119-7. 
• Hardy, Michael (1982). Gliders and Sailplanes of the World. Shepperton: Ian Allen. pp. 54–55. 
• Simpson, R. W. (1995). Airlife's General Aviation. Shrewsbury: Airlife Publishing. p. 342. ISBN 1-85310-577-5. 
• Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions. p. 528. ISBN 0-7106-0710-5. 

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