Boeing Airplane Services (BAS) has begun work on the first 747-300 freighter conversion as it gears up for a launch of a similar modification for the 747-400, possibly by the end of this year.

The 747-300 "special freighter" programme is going ahead on the back of a firm order from Atlas Air for the modification of three -300 combis. Although two stretched upper-deck (SUD) 747-200s were modified to freighters by Boeing for KLM in 1998, this deal is the first for a genuine 747-300.

There are around 79 747-300s in service, along with 12 -100/200 SUD passenger models. BAS president Joseph Gullion says he sees "a minimum of 50 aircraft being done". He adds the conversion for the -300 is "the next logical step" for current - 100F operators wishing to eventually step up to -400F operations. Gullion says that BAS is nearing a launch decision for the 747-400 special freighter conversion and says go-ahead could come "before year-end".

For the -300, the initial "proof of concept" conversions will be undertaken at Boeing's Wichita site in Kansas, with subsequent modifications mainly being completed by BAS partner sites around the world.

The converted -300s will have a revenue payload of approximately 106,690kg (235,000lb) with an overall cargo volume of 738m³ (26,600ft³). The conversion includes changes to the internal configuration of the extended upper-deck cabin's floor to maximise main-deck cargo height, and strengthened main deck floor beams and panels.

BAS says range with full payload will be 7,770km (4,200nm). A proposed flightdeck upgrade for "Classic" 747s is "not currently slated to happen" with the -300s, adds the cargo airline. The upgrade remains an option in future conversion packages which could eventually cover more than half the current fleet of -300s.

Source: Flight International