Let L-410

The Let L-410 Turbolet is a twin-engine, unpressurized short-range transport aircraft designed and produced by the Czech manufacturer Let Kunovice, renamed Aircraft Industries in 2005. Developed in response to an Aeroflot requirement for an Antonov An-2 replacement, it first flew on 16 April 1969 and entered operation in 1970. It has been used as a regional airliner and utility transport by civil and military operators, and is capable of landing on short unpaved runways in temperatures from −50 to +50 °C.

Development

Work began in the mid-1960s around a preliminary design designated L-400, studied for both airliner and cargo roles. The revised design was renamed L-410 Turbolet, and the XL-410 prototype flew on 16 April 1969 with Vladimir Vik and Frantisek Svinka at the controls; it was displayed at the 1969 Paris Air Show. Delays to the Czech Walter M601 engine meant the prototype and the first production model used imported Pratt & Whitney Canada PT6-27 engines with Hartzell HC-B-3TN-3D three-blade propellers. The M601, paired with Avia V 508 propellers, was introduced on the L-410M. The L-410 UVP was developed for Aeroflot with increased wing and tail area for STOL performance, reducing seating to 15. The L-410 UVP-E flew in 1984 with M601E engines, V 510 five-blade propellers, a 6,400 kg maximum take-off weight and provision for tip tanks; quantity production began in 1986. More than 1,000 aircraft had been built by 1990. FAA approval followed on 11 March 1998, EASA certification on 4 February 2005 and 28 March 2007, and FAA certification of the UVP-E20 on 30 June 2015. In the mid-2010s about 15 aircraft were completed annually. UGMK acquired a majority stake in 2013; the L 410 NG flew on 29 July 2015, was certified in late 2017 and entered serial production in March 2018. OMNIPOL acquired the Kunovice plant in 2022. Over 1,200 had been built by 2016, with more than 350 in service in over 50 countries.

Design

The L-410 is an all-metal high-wing aircraft with retractable landing gear. The UVP-E has two hydraulic circuits, one primary and one for emergencies, and a 28V DC main electrical system. De-icing uses pneumatic leading-edge boots and electrical heating of propellers, windshields and pitot-static heads. The UVP-E20 is powered by two General Electric H80-200 turboprops of 597 kW driving 5-bladed Avia AV 725 propellers, with a maximum take-off weight of 6,600 kg, 19 seats, 1,800 kg payload, 405 km/h cruise and 1,500 km range. It is certified for IFR operation, CAT I ILS approaches and flight in icing conditions. The L 410 NG has a lengthened nose, enlarged rear baggage area, new wing, Garmin G3000 glass cockpit, GE H85 engines of 850 shp, 7,000 kg MTOW, 2,500 km range and nine hours endurance.

Operational History

By 1985 around 500 aircraft had been delivered to operators within the USSR, and the type remains widely used in ex-Soviet states, particularly Russia. Others were sold to airlines in Asia, Africa, Central America and South America, with 40 in European commercial and skydiving use. In July 2015, 178 were in airline service: 73 in Africa, 58 in Europe, 41 in the Americas and 6 in Asia-Pacific and the Middle East, the largest operator being Air-Tec Global with 25. The Myanmar Air Force operates at least three, delivered in violation of EU sanctions. The type has been involved in 118 accidents.

Variants

• L-410A: First production series with Pratt & Whitney PT6A-27 engines and three-blade Hartzell propellers; 25 built.
• L-410M: Second series powered by Walter M601A engines with three-blade Avia V508 propellers.
• L-410UVP: Third series with 0.80 m greater wingspan, raised horizontal stabilizer and STOL performance, seating 15.
• L-410UVP-E: Fourth series with M601E engines, five-blade Avia V510 propellers, optional tip tanks and 19 seats.
• L 410 NG: Redesigned version with GE H85 engines, Garmin G3000 glass cockpit, doubled baggage capacity and roughly double the range.