Guy Norris/LONG BEACH
The roll-out of a new aircraft is a major event for any airframe manufacturer, but, for Boeing's Douglas Products division, the 10 June unveiling of the 717-200 is nothing less than pivotal.
Coming hard on the heels of the news that the MD-11 line is to be closed in February 2000, the importance of the 717's success to the beleaguered Douglas cannot be overstated. Since its take-over by Boeing, the rebirth of the MD-95 as the 717 has been virtually the only good news for the Long Beach site.
Designers and engineers have migrated north to Seattle and the MD-80 and MD-90 lines are being shut down - the latter was only just into its third full year of production when the axe fell. Even the study into starting a 737 line in Long Beach seems to have created more uncertainty.
Although not unexpected, the decision to close the tri-jet line comes at a poignant time, therefore, for the workforce as it watches the last "home grown" Douglas design, and its main hope for the future, roll out in Boeing's house colours of red, white and blue.
And what of those hopes? Boeing believes that the 717 stands at the threshold of a market so large that it could sustain a production rate of 10 a month by 2003, yet only 55 are on firm order. Salesmen now battling Airbus Industrie's A319M5 for several large DC-9 replacement orders, are waiting for positive programme results to help bolster their case. Yet they, and potential customers, will have to be patient. The first aircraft will not fly until September, almost three months behind the original schedule, and Douglas faces a hectic eight months to certificate the small twinjet.
There are still some significant hurdles to cross before the 717 flies. Problems with the BMW Rolls-Royce BR715 turbofan emerged fairly late in the parallel engine development effort and crucial redesigns to the compressor and containment case remain to be validated. "One of the problems is that, when you have an engine development programme pacing an aircraft programme, you always have the chance of some setbacks," says 717 programme manager Jim Phillips. "When we began looking at this we realised there was no existing engine capable of meeting the emissions, noise and efficiency targets. The only engine that could meet them had not been developed and we knew it was a risk, so I'm not surprised about a few months delay. All in all we are amazingly close to where we thought we'd be at this stage," he adds.
Not surprisingly perhaps, the sophisticated new systems introduced on the aircraft itself also bring their share of problems to the development effort. Chief among these are what Phillips describes as "integration issues" with two new items - the flight management system (FMS) and the electrically signalled (fly-by-wire) spoilers. The FMS problem is a software glitch within the Honeywell-developed Versatile Integrated Avionics (VIA) computers that form the heart of the aircraft's flightdeck. The VIA processors also manage the flightdeck displays, as well as functioning as the central caution warning and flight data acquisition systems.
The problem with the fly-by-wire spoiler is the discovery of a rare failure condition which results in inadvertent deployment. "There were a couple of areas where we are going back to redesign them because, in isolated situations, there was a chance of inadvertent deployment. Safety is our priority and we said 'We're not going to do that'," adds Phillips. The manufacturers involved, chiefly Parker and Lear Ashe (part of GEC-Marconi), have now begun validation testing of the redesigned system.
In virtually every other respect, the 717 is ready to fly. "Quite frankly, you could fly with these engines, but we're going all out for safety, so we will move the programme around to do a lot more of the early tests on the ground," says Phillips. The full anti-skid brake and air conditioning system test efforts, for example, will be completed during the run up to the first flight rather than immediately after, as originally planned.
The successful passing of other hurdles, meanwhile, gives Phillips confidence that an early September first fight target is realistic. "We've got through ground vibration testing and we have finished static load tests on the pylon, as well as fatigue tests, electrical power system tests and high HIRF [high intensity radiated field]". The biggest single hurdle now remaining is probably the full engine blade-off test coming up in July, says Phillips. "We've been through bird ingestion, crosswind, hail/icing and endurance tests - they're all behind us. Now we are finishing cyclic endurance tests and getting the compressor cleared," he adds.
Around 6,000 Douglas workers, or more than half the current Long Beach workforce, face layoff in early 2000 when the MD-80/90 and MD-11 follow each other into the history books. Some will be taken on as the 717 programme expands. These are the people, above all others, who are hoping for deliverance in the shape of a successful 717 flight test, certification and sales effort.
Source: Flight International
