By Vovick Karnozov
AWN Moscow-Based Columnist

Two Ukrainian aviation companies, Antonov design bureau and Aviant state plant, have begun tests on a first operable example of the An-32-100, a further development of the 25-year-old design (the An-32 flew for the flight time on 9 July 1976).

Since production launch in 1982, Aviant has delivered 352 An-32s, mostly to foreign customers. In service with 22 nations worldwide, these aircraft have logged over 1.2 million flight hours. With the An-124 Ruslan production terminated several years ago (this type remains in production at Aviastar of Ulianovsk, Russia) and new designs still lacking firm orders (the Tu-334 and An-70, whose production lines are being set up at the company's manufacturing facilities in Kiev), Aviant has to rely on the An-32 as its only product currently available for sale (with a possible exception of the Ruslan - the plant can complete unfinished Ruslan airframes should there be a customer prepared to pay for this).

Outwardly, the An-32 closely resembles a previous Antonov design, the An-26, from which it had been derived. The major visible difference is two king-sized Ivchenko AI-20D Series 5 engines, each 5180 hp, in lieu of the far more compact 2550-hp AI-24s. The An-26's fuselage, undercarriage and wing were beefed up to sustain higher loads and speeds. Having similar cargo cabin dimensions (inner volume 60 cu.m), the original An-32 featured higher gross weight (27t against 24t for the An-26), higher cruise speed (470-530 against 420-440km/h) and better climb performance (8000 m vs 6000 m in 19 minutes), while showing almost the same range with full tanks (some 2300 km). The An-26 itself had been derived from the An-24RV 48-seat passenger turboprop operational since 1969.

Unlike many other airplanes of the Soviet era, the An-32 was designed primarily for export, most notably for India whose air armed forces had a requirement for a light air lifter able to operate from short, hot-and-high aerodromes in the mountain areas (ambient temperatures up to 55 degree Celsius, airfield height above sea level to 4500 m). Such an airplane was of a little interest to the Soviet air force, which had opted for another Antonov design, the An-72 (first flight in 1977, in production since 1985) as its primary lightweight short takeoff and landing (STOL) transport. However, the An-32 did go in service with local customers, both civilian and militarized, although in relatively small numbers. According to Russia's Federal Service of Air Transport (FSVT), in 1999 Russian airlines operated 36 An-32s along with 364 An-24s, 227 An-26s and 35 An-30s. These other types feature a high airframe and systems commonality with the more recent An-32, the fact that facilitated its introduction into service. Moreover, the An-32's AI-20 engine had been seen on Antonov An-12 and Ilyushin Il-18 four-engine airplanes.

In the early 1980s the An-32 had a check in Afghanistan, where it was flown by governmental armed forces in a tactical transport role. Hilly, hot and dusty Afghanistan provided exactly the kind of conditions for which the plane was designed. The airplane proved its worth, often lifting off from short unpaved runways and immediately entering a high-pitch climb so as to escape shells and bullets of Muslim rebels in ambushes near aerodromes. The rugged airframe was able to absorb considerable damage, and climb up to 4800 m on one engine. Afghan experience helped Antonov find many foreign customers - except for India and Afghanistan, the plane has been exported to Peru, Ethiopia, Nicaragua, Mexico, Shi Lanka, Columbia, Bangladesh, Croatia, etc. Although the An-32 has been used primarily as a military transport, there have been many cases when it carried commercial cargoes, and even passengers, in airline service, including that with Aeronica and Carricarga in Latin America.

Although foreign customers were generally satisfied with the plane's performance, they believed that the gigantic engines can lift much bigger loads than the manufacturer's limitation. Prompted by customers' requests for a higher payload, Antonov developed the An-32B with maximum payload capability of 7200 kg and then the An-32P dedicated fire-fighting version carrying 8 tons of water. Certified in 1995, the latter version, operated by Antonov Airlines, has visited many foreign counties for demonstration and real use of its fire-fighting capabilities.

The most recent version, the An-32-100, was developed in an effort to keep the aging plane up to modern requirements. Antonov and Aviant hope that modernization will help to generate new sales. In 1982-1994 Aviant delivered 337 airframes, while being able to sell only 15 aircraft since 1995. The focus of modernization is placed on improving the plane's operational economics by extending the engine's TBO and uplifting weight limitations. The "-100" features AI-20D Series 5M engines with TBO of 4000 hours and assigned lifetime of 20,000 hours. It has a modified engine control system which automatically de-rates on-shaft power depending on ambient temperature and engages "extreme power mode" when an engine fails during takeoff. Maximum takeoff weight for the An-32-100 has been increased up to 28.5 t, and maximum payload up to 7.5 t. This considerably improves An-32's efficiency as a freighter, allowing transporting a 7.5t load 1,000 km and 5.5 t load 2,000 km.

The "-100" will provide a base for various modifications differing by on-board equipment. On customer request, the crew can be reduced to two pilots, for which the cockpit should be re-designed. There is a patrol version with additional (strap-on) tanks, allowing carriage of a 3t load over 3,200 km. This one is aimed at meeting requirements of a small nation's naval air arm. Aviant says that advanced manufacturing technologies mastered on the An-32 in early 1980s were specially developed to guarantee a high degree of airframe protection against corrosion in the conditions of high humidity.

For customers wishing to minimize fuel burn at the expense of hot-and-high performance, Aviant is offering a version with AI-20M 4250-hp engines. These have hourly fuel burn of 982 kg against 1000 kg for the AI-20D Series 5 at a same cruise speed. The "20M" has a smaller propeller (of the same four-blade Stupino AV-58 series), 4.5m in diameter versus 4.7m for "20D", resulting in lower noise levels inside the cockpit and cabin. Installation of a western power plant is possible on customer's request, as well as development of a new, more effective multi-blade propeller for the AI-20-series engines.