INTERLAKEN, Switzerland - There is "clearly a market for 70 passengers," but Boeing says that it is "not evaluating seriously" such a possible regional jet, according to Boeing Commercial Airplanes 717 brand manager Richard Wynne.

However, Boeing is seriously re-evaluating an 86-passenger "-100X" variant of its 717-200.

Just last year, Boeing product strategy officials were at pains to say that there was no business case for a smaller version of the 106-passenger -200, but actual experience with that machine has shown unexpectedly attractive operating costs.

These arise from a reduction of two tons in maximum take-off weight and better fuel burn from the Rolls-Royce Deutschland BR715 engines.

Now, RRD is exploring the development potential of the engine, which can be offered at thrust levels from 13,000lb and upwards and could be suitable to power, say, a 74-seat Boeing 717 that could be dubbed "-050." Wynne acknowledges that this would be the logical size of any smaller variant, with the capacity obtained by shortening the cabin of the -100X by two seat rows.

Boeing marketers want to be able to launch the 717-100 by year's end in order to meet airline requirements for deliveries before 2004. Wynne says that Boeing could not deliver before the end of 2002 but "can make the second half of 2003."

He says that no launch criteria have been defined: "We need to have a certain number. It would be nice to have someone buy both the -100 and -200."

The 717 brand manager says that since non-recurring development costs "are low by Boeing standards" the manufacturer can be "relatively liberal on the criteria."