INDUSTRI PESAWAT Nusantara Terbang (IPTN) hopes to fly the first of three stretched N270 prototypes, designed specifically for use in the North American market, by late 1998.

Louis Harrington, president of IPTN's American Regional Aircraft Industry (AMRAI) joint venture says that a 12-month flight-test and certification programme is being planned, which will lead to delivery of the first Indonesian-built N270 production aircraft by the end of 1999.

The three additional prototypes will be used to test and certify aero- structural changes made to the N270. No new subsystem testing is envisaged and it is hoped to avoid any further static tests through analysis of existing N250 data.

Modifications to the basic N250-100 airframe will centre on a forward and aft fuselage plugs, adding 3m to the overall fuselage length, and strengthened wings. Compared to the 64- to 68-seat N250, the stretched aircraft will be configured for 70-78 seats, depending on seat pitch, and include an extra forward luggage hold. The higher-gross-weight N270 will be able to carry a further 1,360kg of payload.

The N250's Messier Dowty landing gear will be strengthened for the increased weights. Other changes include software refinements to the aircraft's fly-by-wire flight-control system and modifications to the hydraulic actuators for the N250's APIC auxiliary power unit to be made an optional extra.

The N270 will powered by uprated twin 2,980kW (4,000shp) Allison AE2100C turboprop engines. The new version will have an equivalent performance to the N250-100, with a maximum cruise speed of 330kt (610km/h) and a full payload range of 1,480km (800nm).

Mobile, Alabama-based AMRAI is being set up to support both the N250-100 and N270 in North and South America. AMRAI will initially take between two and five IPTN-produced N250-100s in late 1998 for use mainly as demonstrators. It then plans to begin local assembly of the N270 in August 1999, using IPTN-supplied kits.

Three Indonesian domestic and regional airlines have signed firm orders for a total of 26 additional IPTN N250 regional turboprops. According to Dr Bacharuddin Habibie, head of IPTN, this takes the orderbook for the N250 to 219, with deliveries due up until 2025. The latest signings by Merpati Nusantara Airlines (15 aircraft), Sempati Air (six) and Bouraq (five) are confirmation of agreements made at the roll-out of the N250 in November 1994.

Source: Flight International