YS-11M-A

The YS‑11M‑A is a Japanese twin‑engine turboprop that evolved from the original NAMC YS‑11 transport, first flown in 1962. In the early 1970s Nihon Aircraft Manufacturing Corporation (NAMC) began converting selected YS‑11 airframes to the M‑A standard, installing two Allison 250‑B17 / B19 turboprop engines, reinforced wing spars, and upgraded avionics. The conversion raised cruise speed to roughly 460 km/h, extended range to 2 400 km and allowed operation from shorter, unpaved runways, making the aircraft attractive to regional airlines and government agencies throughout Asia and the Pacific.

Key features include a fully pressurised cabin that can accommodate up to 60 passengers or a mixed cargo‑passenger load, a nose‑wheel steering system for tight ground handling, and a modernized navigation suite with VOR/DME, ILS and later GPS capability. Structural improvements also increased payload capacity by 1 200 kg compared with the original model.

The YS‑11M‑A demonstrated Japan’s ability to refurbish and extend the service life of an indigenous design, supporting domestic connectivity during a period of rapid economic growth. Its reliability and low operating costs helped establish a niche for short‑haul turboprop service in regions where jet aircraft were uneconomical, leaving a lasting imprint on post‑war Asian aviation.