First customer aircraft now flying correctly after faulty assembly tool introduced twist in light jet's left wing
Sino Swearingen Aircraft (SSAC) is checking, and where necessary redesigning, production tooling for the SJ30 light jet after replacing the left wing on the first customer aircraft because of twist introduced by a faulty assembly tool.
Inadequate tooling is one of several issues the company faces getting the SJ30 into production after a decades-long development effort. Another is the "hiccup" in funding from Taiwan that caused the San Antonio, Texas-based company to miss supplier payments and lay off workers, says Steve Crawford, senior vice-president operations.
Twist in the outboard left wing caused aircraft 006 to run out of roll trim, and after four flights SSAC decided to replace the wing, says Crawford. The aircraft is now flying correctly, he says, and delivery is expected in the "next two to three weeks". Checks revealed similar twist in the left wing of aircraft 008, now in final assembly, and that has also been replaced.
Alerted to the problem, SSAC is analysing all the tooling at its Martinsburg, West Virginia fabrication and subassembly plant and on the final assembly line at San Antonio. "Three-quarters of the tools require some rework, some major enough that they are not good rate tools so we are changing the design," says Crawford.
SSAC now expects to deliver just 13 SJ30s by the end of next year, but is buying components for 17. The planned production rate is still under review, and ranges from 50 to 150 aircraft a year, Crawford says, adding that he has recommended redesigning the SJ30 for automated manufacture and modular assembly if the rate is above 60 a year.
Representatives of the Taiwanese government visited the company recently to assess progress and, Crawford says, indicated they would recommend the Taipei cabinet release sufficient funding to allow SSAC to invest in making SJ30 production viable.
Plans call for more of the work, including staffing of subassemblies, to be performed in Martinsburg, and for a new building to be constructed in San Antonio to allow a nose-to-tail assembly line.
SSAC is also moving to control design changes, made mostly for producibility, by dividing the first 40 SJ30s into four blocks starting with six "pre-production" aircraft.
Source: Flight International
