With Boeing’s 777-200LR on track for certification by year-end, the US manufacturer’s tussle with Airbus will reach a new arena – the ultra-long-range market
Four months can make all the difference in aerospace. At the roll-out of the 777-200LR in mid-February, Boeing put a brave face on the disquieting fact that the twinjet was making its public debut with a mere five firm orders from two customers – the smallest pre-first-flight backlog of any jet airliner in its prestigious history.
But by June, just three months after the first flight, it is a different story. The two test aircraft have already stormed past the halfway point of the flight-test programme, while the customer count has doubled following sales agreements with Air Canada and Air India, which were secured as part of an intriguing double-act with the 787. The directly related 777 Freighter (which is based on the -200LR airframe) has also been launched on the back of orders from Air Canada and Air France, meaning that sales commitments have quickly climbed to about 36 passenger and freighter aircraft – the total will depend on how customers decide to split their orders between the -200LR and other 777 variants.
More importantly perhaps, Boeing is busy crunching the numbers from the vital range performance tests that will be pivotal in its bitterly competitive struggle with the Airbus A340-500. Details of the nautical air miles (NAMS) thrust-specific fuel consumption (sfc) tests were not available as Flight International went to press, but Boeing 777 vice-president and programme manager Lars Andersen says: “We’re not ready to tell anyone yet what the answers are, but we don’t think there are going to be any surprises.”
This effectively means that Boeing expects the 777-200LR to achieve the same basic degree of relative range improvement in flight test that was seen with the -300ER. “We changed the -200LR book value to represent the trends we saw with the -300ER, and we’re out portraying the aircraft in that way,” says Andersen. Building on range increases demonstrated by its 777-300ER stablemate, the company believes the aircraft will be capable of distances up to 17,450km (9,420nm).
“That’s around 900nm more than the A340-500,” says Andersen. Originally expected to reach ranges of 13,300km, the -300ER is now “out to 7,940nm”, he says, thanks to the combined benefits of an increased take-off weight, better-than-expected fuel burn in cruise and a package of drag-reduction, engine-performance and weight-reduction enhancements. “When we went into flight tests with the -300ER, we found it was 1% better than predicted in NAMS, and when we began delivering aircraft, these turned out to be around 1% better than the flight-test aircraft. On top of that, we’re adding another 1.25% with engine improvements and the final grouping of enhancements that will be introduced this October.”
The package includes adding extra vortex generators to the outboard wing. “We’re looking at using smaller 737 Next Generation-sized vortex generators on the inboard wing at around the quarter chord line,” says Andersen. Other features include a General Electric-developed enhancement kit for the GE90-115B engine and variable vanes in the ram air exhaust duct. The engine upgrade is expected to generate a 0.8% reduction in sfc over the baseline design, primarily the result of improved three-dimensional aerodynamic design of a newly cast set of low-pressure (LP) turbine blades and vanes. Boeing claims the enhancements will give the 777-300ER a 22% fuel burn per seat advantage over the Airbus A340-600, and the -200LR as much as a 25% advantage over the -500.
In terms of expanding the markets already opened up by the 777-200/-300 models, the newer version will be able to carry 22,880kg (50,400lb) more payload than the -200ER, or fly the same payload 2,870km further. The -300ER can carry 28,150kg more payload than the baseline 777-300, or fly 3,240km further.
Engine performance
However, it is the in-service performance of the GE90-115B engines on the -300ER that gives Andersen even greater confidence of success for the -200LR. “The engines have been doing very well in terms of performance,” he says. “They’re even coming out of the factory with better sfcs than before, and performance retention is right on prediction. When we are in discussions with airlines on the performance of the aircraft, we typically, on the 777, take into account a 3% degradation after three or four years. So far what we’ve seen on the -115B is right on that trend line.”
General Electric GE90 projects general manager Chaker Chahrour adds: “I’ve been around for a while, and I’ve never seen a programme that has overachieved by so much.” GE is planning a significant ramp-up of GE90 engine production to accompany the growing orderbook for the 777. “We delivered 54 engines in 2004, and plan around 80 for 2005,” says Chahrour. “We will go into the high 90s in 2006 and we are looking at going to around 130 in 2007. This covers all models of the engine, although predominantly it’s the -115B.” Boeing plans to be producing seven 777s a month by 2007, of which five will be -200LR/300ERs.
The basic reliability of the -300ER is also another plus as regards prospects for the -200LR, says Andersen. The 17 aircraft in service by early June had established a rolling 12-month average dispatch reliability rate of 0.992, while the engine in-flight shutdown rate and removal rate had both remained at zero. In service, the aircraft had accumulated a high 64,000h against a relatively low 4,100 departures and 8,200 flight cycles. “Reliability continues to become more important in a long-haul fleet, particularly when it comes to keeping slots at distant destinations, and keeping a track on crew costs,” says Andersen. “The more distant the range, the more they need to be totally reliable.”
Auxiliary tanks
To achieve the -200LR’s maximum quoted range, Boeing is offering up to three 7,000 litre (1,850USgal) auxiliary fuel tanks in the belly space. Proof-of-concept demonstration tanks have been fitted to the second test airframe, WD002, which joined the flight-test programme at the end of May. “We have got all three tanks in it, although we are still evaluating the need for them on some routes,” says Andersen. “We convinced ourselves and Pakistan International Airlines (PIA) that they didn’t need a tank. But with Air India we’re looking at a couple of cities where there might be a need.” He adds that no operator has yet specified the tanks.
The test units are not the production tanks and “we’re just checking them out”, says Andersen, who adds: “These have not gone through all the rigorous certification tests of the full production tanks, and are probably a bit heavier than the ones we would use in a service aircraft.” The tanks are also expected to come in useful during a planned eight-week “world tour” demonstration programme that will see WD002 fly to cities in the Middle East, Asia, the South Pacific and North America after making its public debut at the Paris air show.
The second test aircraft is also configured with a special interior designed by Boeing’s long-time cabin and interior developer, Teague. Blending features from both the latest 777 and 787 cabins, the aircraft also has several advanced passenger features, such as a pico-cell network to allow the potential use of mobile phones in-flight.
In a recent petition to the US Federal Communications Commission, Boeing said it planned to test a dual-technology – CDMA2000 and GSM – pico-cell network both on the ground and in the air, and to demonstrate the benefits of a system in limiting potential interference to terrestrial wireless networks.
In the run-up to Paris, however, both WD001 and 002 have been engaged in intensive flight tests, with 001 based at Edwards AFB, California in early June, and 002 flying out of Boeing Field. With hours quickly building towards 300h out of a planned 500h, the effort is on track for completion by the end of September, with planned certification around December, says Andersen. “In terms of aircraft flight testing, it’s been a very good flight test from the perspective of not having many squawks, and we have been able to do everything without having to fly at weekends. We did have to go back to Edwards, however, because we didn’t get the right weather for some of our tests.”
Until now, the test work at Edwards has been aimed at VMCG (minimum control speed with critical engine failure during take-off run), and VMCA (minimum control speed with critical engine out, out of ground effect). To attract some prospective carriers, notably Singapore Airlines, it is thought Boeing and GE have also decided to offer the full 115,000lb-thrust (512kN) capability of the GE90 on the -200LR, as well as the baseline GE90-110B derate version as standard.
“We originally planned to certify at 110,000lb thrust, but we did some tests at 115,000lb and didn’t find any issues,” says Andersen. “That’s good news, because we think there’ll be some operators that want 115,000lb for obstacle-limited airports.” GE confirms “the plan is now to offer 115,000lb as the thrust option”, rather than an interim “thrust bump” rating of 113,000lb that was planned until recently.
Take-off tests
By early June, US Federal Aviation Administration pilots were performing take-off tests at Edwards on WD001 as part of the certification programme, while other tests were under way on the tail-strike protection system and defining the buffet boundary. Meanwhile, work on WD002 had shifted to auto-throttle evaluations, testing of the Honeywell-developed aircraft information management system (AIMS) and post-NAMS work on the engines.
Against the frantic background of flight tests, demonstration tours and joint sales campaigns with the 787 family, Boeing has also firmly launched the 777 freighter version on the back of an order for five from Air France. The agreement, revealed by the carrier on 19 May, also includes three options and covers deliveries from late 2008. Air Canada has also stated an intention to acquire two 777Fs as part of its widebody fleet-renewal programme, although the agreement has yet to be completed.
The aircraft will have a range of 9,200km with full payload, and will be flight tested in 2008, with first deliveries in the fourth quarter of that year. “We’re in the phase of firming up the configuration now, so we’re doing a lot of trade studies,” says Andersen.
“We’re working on preliminary loads, both externally and internally, as well as the cargo handling configuration, and we so far we have had two working groups and will have a third meeting in September. We’ve had a lot of good input from the airlines, and it is the first time the cargo operators have had a chance to be involved up front in the design of a [Boeing] freighter.”
First delivery
The -200LR flight-test aircraft will, meanwhile, be refurbished before delivery of WD002 to launch customer Pakistan International Airlines (PIA) in January 2006. The second aircraft, WD001, which will take longer to refurbish, will be handed over to PIA in February. Overall, Boeing predicts possible sales of 300 aircraft in the -200LR category over the next 20 years, with a further 200 sales predicted for the 777 Freighter.
Despite its slow start, confidence is growing at GE. “I think it’s going to be a winner,” says Chahrour. “The reason it hasn’t sold so well so far is because of the timing. Together with the 777-300ER and the 787 family, it will fit all the long-range requirements, and obviously with a range in excess of 9,300nm, the -200LR is in a league of its own.”
The double-act sales routine with the 787 is also likely to see further additions to the 777 orderbook, says Andersen. “It’s been really encouraging to see the joint purchases of both 777s and 787s, and we’ll see more of that. It’s turning around now because of the trends you’re seeing in the world economy, passenger traffic growing and airlines deciding it is the right time to update their fleets. Plus having an aircraft like the -200LR gives them the ability to add additional non-stop city pairs they haven’t been able to link before. The -200LR really manifests the intent of an ultra-long-range aircraft.”
GUY NORRIS/LOS ANGELES
Source: Flight International
