ICA IS-29

IS-29, IS-31, and IS-33
IS-29D2
Role	Club-class Sailplane
National origin	Romania
Manufacturer	ICA
Designer	Iosif Silimon
First flight	April Template:Avyear
Number built	>200

The ICA IS-29 was a sailplane built in Romania in the 1970s. The prefix IS comes from Iosif Silimon, the Romanian IAR (Industria Aeronautică Română) aeronautical engineer who designed it. The 15-metre (49 feet) single place sister of the IS-28 series, the IS-29D2 single-seater has retractable gear, camber-changing flaps and Hütter type airbrakes on the upper wing surface only. The T-tail has a fixed stabilizer and elevator. The –29D model is of all metal construction while the earlier –29B has wooden wings. Developments include 19 metre (62 ft) -29E2 and 20 m (66 ft) -29E3 versions and a flapless, fixed gear 16.5-metre (54 feet) ‘club’ model -29G.

The aircraft demands reasonable training skills from the pilot, being known for its capability of entering a stall quite quickly, can lead to a spin. This is not uncommon in many gliders. The 29d's supposed deep stall was long debunked by exhaustive test flying in Australia and was well documented in various issue of " Australian Gliding" , the official GFA magazine at the time, in the 1970's. Recovery from stall/spin sitations are similar to for example, the Szd Puchacz. It's general handling is excellent and is highly aerobatic in the right hands, with high positive and negative strength factors. The pilot should be always aware of the stalling speed during flight and especially at the proximity with the ground (at take offs and landings) where the recovery from this scenario is impossible to perform.

The IS-29 was also produced in a motorglider version, designated the IS-29EM. This shared the low-set wings and three-point undercarriage of the IS-28M2, and the new wings of the IS-28MA.

Variants

• IS-29
  • IS-29B - wooden wings of 15-metre span
  • IS-29D
    • IS-29D2
      • IS-29D2 Club - Club-class version of IS-29D2
  • IS-29E - open class version with ballast tanks
    • IS-29E2 - version with 19-metre wings
    • IS-29E3 - version with 20-metre wings
  • IS-29EM - motorglider version
  • IS-29G - Club-class version with 16.5-metre wings
• IS-31 - IS-29 with 20-metre wings and linked flaps and ailerons
• IS-33 - IS-29 with tanks for 150 kg (300 lb) of water ballast

Specifications (IS-29D2)

Data from

General characteristics

• Crew: 1
• Length: 7.03 m (23 ft 1 in)
• Wingspan: 15 m (49 ft 3 in)
• Height: 1.68 m (5 ft 6 in)
• Wing area: 10.4 m² (112 sq ft)
• Aspect ratio: 21.5
• Airfoil: root:Wortmann FX 61-163, tip:Wortmann FX 60-126/1
• Empty weight: 220 kg (485 lb)
• Max takeoff weight: 330 kg (728 lb)

Performance

• Stall speed: 65 km/h (40 mph, 35 kn)
• Never exceed speed: 240 km/h (150 mph, 130 kn)
• Maximum glide ratio: 37:1 at 93 km/h (58 mph; 50 kn)
• Rate of sink: 0.58 m/s (114 ft/min) at 78 km/h (48 mph; 42 kn)

References

• Soaring Society of America
• Taylor, Michael J. H. (1989). Jane's Encyclopedia of Aviation. London: Studio Editions. p. 528.
• Hardy, Michael (1982). Gliders and Sailplanes of the World. Shepperton: Ian Allan. pp. 54–55.
• Coates, Andrew (1978). Jane's World Sailplanes and Motor Gliders. London: MacDonald and Jane's. p. 124.
• Simpson, R. W. (1995). Airlife's General Aviation. Shrewsbury: Airlife Publishing. p. 342.
• Jane's All the World's Aircraft 1977-78. London: Jane's Yearbooks. p. 608.