Saab has launched an urgent study to increase the maximum take-off weight (MTOW) of its 340B regional turboprop following a 10% reduction in available seats on US-registered aircraft.
In its investigation into the January 2003 Air Midwest Beech 1900D crash at Charlotte Douglas airport, North Carolina, the US National Transportation Safety Board (NTSB) determined the probable cause was a loss of pitch control during take-off exacerbated by the aircraft's aft centre of gravity (Flight International, 2-8 March). Following the report, the US Federal Aviation Administration increased average passenger weight assumptions for small commuter aircraft from 82kg (180lb) to 105kg.
Saab Aircraft Leasing says several of its US customers using 37-seat Saab 340s have had to eliminate two or three seats as a result of the revised averages, and have urged Saab to issue service bulletins allowing increased take-off weights. Saab Aircraft Leasing president Michael Magnusson says a bulletin for the 340A was issued in May, increasing the take-off weight from 12,700kg to 12,925kg. "We were quite conservative in our initial findings, and were thus able to increase the payload by 500lb [230kg] easily because we had a wide safety margin," he says. Work to increase the payload of the longer-range 340B is more complex, he adds. The 340B has a MTOW of 13,155kg and Saab says the target increase is "as much as possible", potentially 500kg.
Source: Flight International
