All Nippon Airways introduces Masami Tsukamoto as the first airline pilot outside Boeing who was allowed to take the controls of the 787-8. When the day finally came to fly the first Dreamliner delivered to ANA from Seattle to Tokyo, Tsukamoto’s reading on the pre-flight fuel gauge still surprises him three years later.
As a career ANA captain, Tsukamoto had flown the Seattle-Tokyo leg many times in different aircraft. He knows by memory that a 747-400 needs at least 136,000kg (300,000lb) to make that trip. The smaller, leaner 777-300ER needs nearly 100,000kg. For the 787-8, the fuel gauge that drizzly September day in Seattle read 63,500kg for the Pacific crossing.
“When I looked at the [fuel] quantity, I couldn’t believe that these were good enough,” Tsukamoto says in a recent interview at ANA’s headquarters in Tokyo.
Tsukamoto is not alone. In Warsaw, LOT Polish Airlines chief executive Sebastian Mikosz says the 787 is “like a glider”, describing an average fuel flow per hour of only 2t (4,410lbs), compared with his fleet average of 4.6t. In Addis Ababa, Ethiopian Airlines chief pilot Yohannes Hailemariam says the fuel load that pushes a 767-300ER to Rome can propel a 787-8 to Frankfurt, nearly 20% further on a direct line. In Luton, UK, Thomson Airways managing director John Murphy says the 787 is also demonstrating nearly 20% improvement, a figure that is “good for us”.
Flightglobal has visited five early operators with a combined fleet of 71 787s now in service on three continents, and the theme is that the aircraft has delivered on Boeing’s contractual fuel-efficiency guarantees. This performance – combined with the aircraft’s ability to connect secondary markets at ranges well beyond the reach of its predecessors – has sustained the 787 in the market despite waves of technical glitches.
Three years after the 787 entered service, 24 airlines operated 193 of the aircraft as of early November, according to Flightglobal’s Ascend Fleets database. That represents 42% of a backlog of 456 aircraft. Including the combined orderbook of the 787-8, -9 and -10, Boeing has delivered 18% of the backlog so far, including five 787-9s to three carriers since July.
To sustain the backlog, many things could go wrong after entry into service, but not the 787’s fuel-efficiency promises. Boeing promised a 20% fuel-burn reduction compared with a 767-300 delivered in the early 2000s.
Airlines might accept a long list of programmatic and operational errors that in another era may have seemed devastating. For the 787 programme, the setbacks seem almost unsurvivable in retrospect, including a 3.5-year delay of first delivery, supply chain breakdowns, repeated setbacks on the assembly line, three lithium-ion battery cell venting events, a four-month grounding, and “teething” issues that persist even as the 787 approaches airframe adolescence.
After all that, the 787’s customers would not be so willing to queue for years to obtain the aircraft if Boeing also missed the mark on fuel performance. While some airlines complain that the 787-8 still falls short of the 20% mark listed in the 787 sales literature, they agree that the fleet average beats the contractual minimum.
Each airline measures and prioritises fuel efficiency in different ways, so the publicly released performance figures on the 787 cover a lot of ground.
“When every airline is flying different missions with different configurations, the fuel savings advantage will be different for each one,” says Mike Fleming, Boeing’s vice-president for 787 support and services.
At the bottom end of the scale, LATAM Airlines group, whose Chile-based subsidiary LAN Airlines operates nine of 26 Rolls-Royce Trent 1000-powered 787s currently on order, says in an email that its 787-8 fleet averages a 12% fuel cost reduction compared with its 767-300ERs. That seems low compared with Boeing’s 20% target, but there are different assumptions involved. LATAM wraps fleet acquisition and operating costs into the equation. The carrier also operates newer 767-300ERs equipped with winglets, neither of which Boeing factors in to the 20% fuel-burn reduction it promises.
“LAN, as Americas launch customer, is getting some early production 787-8s, which may not provide the best measure of the type's performance,” says Richard Aboulafia, vice-president for analysis at Teal Group.
On the other extreme are Air Canada’s expectations for the Dreamliner. After taking delivery of its first two General Electric GEnx-1B-powered 787-8s earlier this year, chief executive Calin Rovinescu told analysts that he expects the aircraft to yield 29% lower unit seat-mile cost than the 191-seat 767-300s that are being replaced. In a second-quarter earnings call, Rovinescu cited the example of the Toronto-Tel Aviv route, on which a 251-seat 787-8 can carry 31% more passengers and more than triple the cargo while burning 3% less fuel per trip than the 767.
More typical are the airlines we visited, which occupy the vast middle ground between the LAN and Air Canada extremes.
All Nippon Airways, the 787-8 launch customer, reported in May 2012 – after starting revenue service the previous October – that the Trent 1000-powered 787-8s in its fleet burned 17% less fuel on domestic routes and 21% less fuel on long-haul routes on a per-seat basis compared with a virtual model of a comparable 767. Asked for an update two years later, ANA deputy director for engineering Masaru Nishiwaki says fuel performance remains the same.
In another Tokyo office, Japan Airlines calculates fuel burn by measuring the amount of fuel used per person on board an aircraft, says aircraft performance group director Eisuke Hama. “We have not yet reached the 20% target, but we are coming closer to 20%,” he says. Hama adds that the introduction of engine upgrades, such as the second performance improvement package (PIP2) for the GEnx-1B, means that “fuel efficiency is gradually improving”.
Another key factor in reducing fuel consumption is learning how best to operate a new aircraft.
“You can always make that 0.5-1% impact if you work collaboratively,” says Thomson’s Murphy, who operates eight GEnx-1B-powered 787-8s. “It’s about the design of the aircraft, the engines and how you fly it. Direct routing, at the planning stage, is very important. We want to maximise the optimum altitude, we want to have the pilots asking for shortcuts, and we want the perfect descent profile.”
LOT’s pilots have been flying the 787 since the battery grounding ended in May 2013. (LOT’s inaugural 787 flight from Warsaw to Chicago on 16 January 2013 was famously cancelled due to a 787 grounding order caused by two cases of lithium-ion battery fires.) One quarter of LOT’s pilots are still becoming familiar, but the majority of the carrier’s 787 crews have learned how to maximise the fuel efficiency of the aircraft, says LOT director of product development Michal Leman.
“Pilots can go through numerous simulator lessors, but they also have to learn,” Leman says. “You need to feel the aircraft when you are landing, when to put the engine on, when to stop using the engine and start gliding.”
The 787’s customers talk frequently about the 787’s “gliding” effect. Although the engines remain powered, the shaping of the wing – which flexes up to 3.66m (12ft) in 1G flight – and the use of flight controls to manage structural loading on the wings means the aircraft often feels to the pilot that is maintaining altitude using aerodynamic lift alone.
LOT’s Mikosz recalls sitting in the cockpit on a 787-8 flight from Warsaw to Beijing, which requires a relatively rapid descent after crossing the Gobi Desert.
“Normally with a 767 it was like a stone – you idle down [the engines] and [the aircraft] goes down,” Mikosz says. “Here, [the pilot] said, ‘My glider doesn’t want to go down.’ So she air-braked, she [moved the engine throttles] to idle and pushed the aircraft down. And it was [still] gliding.”
Fuel efficiency is not only a function of the aerodynamic properties of an aircraft. Operational performance can make a substantial difference. A non-aerodynamic drag on fuel efficiency has actually been the 787’s reliability problems, especially in the early days.
“In the beginning, it was difficult, because if you enter a new aircraft into your fleet you have all the time these small issues,” says Leman. “So then you have 5min delay, 10min delay. From the perspective of the customer, it doesn’t matter, because they are flying 8h and will arrive on time. But to reach [the destination] on time you have to burn fuel because you have to go faster.”
Every new commercial airplane goes through teething issues as it goes from flight test to revenue service. The 777 set Boeing’s benchmark for despatch reliability, but even it drew a public rebuke from launch customer United Airlines. The carrier complained a year after the aircraft’s 1995 entry into revenue service that Boeing was slow to resolve an assortment of technical snags. These ranged from gearbox reliability problems with the General Electric GE90 to a leaky passenger exit door that froze shut.
At the depths of the battery crisis in early 2013, Boeing said the 787 was performing better on reliability problems than the 777, citing slightly higher despatch reliability and slightly fewer technical error reports, called EE-1s, submitted to the US Federal Aviation Administration.
A year and a half later, the 787’s rate of progress has diverged from the standard set by the 777, as niggling technical issues continue to lower despatch reliability below Boeing’s expectations for the aircraft’s design.
“From a reliability standpoint, we’re a little behind where the 777 was at this stage,” Fleming says.
As more time passes, however, comparisons with the 777 begin to lose meaning. Thirty-six months after the first 777-200 entered revenue service, Boeing had delivered 151 examples of the 777-200, 200ER and 300 to 16 customers, according to Boeing’s online delivery database. Boeing delivered 198 787-8s and 9s to 25 operators over the last 36 months, while ramping up production to 10 aircraft per month.
Not every airline has complained about 787 despatch reliability. Earlier this year, Boeing announced that one 787 customer had received an award for operating its first aircraft 100 days without recording a single delay related to an onboard technical problem.
Although that carrier has never been named, it is almost certainly Thomson. As a discount charter carrier, its business model is unforgiving for delays that are solely the fault of the airline. More to the point, Thomson is virtually alone among 787 customers with no complaint about the aircraft’s reliability.
Murphy boasts that Thomson has “the most reliable 787s in the world”, despite having one of the highest utilisation rates.
“But we work hard at it,” Murphy says. “We’re constantly reviewing our spares stock and constantly reviewing our despatch reliability. We have a fantastic relationship with Boeing.”
For most other airlines, despatch reliability remains a sore point. Earlier this year, Boeing executives openly discussed a goal of reaching 99.5% fleet-wide despatch reliability by the second quarter of next year, matching the benchmark achieved by the 777-300ER.
In real terms, the difference between 98.5% and 99.5% can be significant to a carrier’s bottom line. ANA, for example, currently operates about 100 787-8 and 787-9 flights combined each day, so that percentage point represents the difference between one and three flights delayed by technical faults every two days.
As 2015 approaches, the target despatch reliability for the 787-8 discussed in public by Boeing executives is no longer 99.5%, but simply a rate over 99%. Three years after entry into service, the 787-8 is still running below Boeing’s design standard, which means the teething issues have still not gone away.
“From our past experiences we understand what it takes to get an airplane to consistently operate above our goal of 99% schedule reliability,” Fleming says.
Like fuel-efficiency targets, despatch reliability is prioritised differently by each airline. ANA, for example, remains slightly dissatisfied with the 787-8’s performance, even though it says its 787-8s have achieved a 99.5% despatch reliability average.
“Our target is 99.7,” Nishiwaki says.
Japan Airlines, meanwhile, has a target despatch reliability rate for its 787 fleet of 99.3% but is now running at 98.6%, says Hama.
“It’s getting better slowly but surely,” Hama adds. “It’s still not there yet.”
Boeing has not released the average despatch reliability rate across all airlines, but one airline executive says it is hovering at 98.3%.
As another early 787 customer, state-owned Air India has an obligation to submit written replies to questions from members of parliament, some of whom have sent regular queries about the 787’s reliability levels. On 14 July, Air India reported 318 service delays on the 787 between first delivery in September 2012 and June 2014.
The key issues driving delays also are a moving target for each airline.
In Addis Ababa, a critical problem for Ethiopian Airlines is a persistent glitch with the 787’s four cabin air compressors (CACs).
“It’s still an issue where every time you fly, there’s one compressor not working,” says Hailemariam.
Other carriers, however, had few complaints about the compressors. Hama says the CACs on JAL’s 787s have had “little, minor troubles”. At ANA, Nishiwaki says the reliability of the CACs is “very, very good”.
Indeed, the part number of the CACs in the ANA 787 fleet has remained the same since entry into service more than three years ago. Other parts in the electrical system have been redesigned several times over the same period, he says, so that the part numbers are augmented with a “-2”, “-3” or even “-4”, but not the CACs.
Boeing is addressing some “reliability issues that we have” on the CACs, a source at the company says.
Ethiopian expects the CAC issue to continue, says Zemene Nega, managing director for maintenance, repair and overhaul. “It is just a fundamental design issue,” he says. “It’s not going to be fixed with software.”
One of the universally problematic parts for airlines has been the variable frequency starter/generators (VFSGs). There are two on each engine, and they represent one of the major innovations introduced by the 787. In all other commercial aircraft, functions such as cabin pressurisation and wing de-icing are powered by bleeding compressed air from the engine. To improve fuel efficiency, Boeing converted those systems to electric power. That required significantly more powerful engine-mounted generators, so Boeing introduced VFSGs on the 787 that each produce up to 250kVA of electricity.
“We have experienced a lot of troubles with the VFSG,” Hama says.
It is an issue that Boeing acknowledges has been a long-term problem, and one that may still not be completely solved. So far, Boeing has rolled out three improved versions of the VFSG, with each upgrade requiring a reinstallation.
“We expect that the latest configuration of the VFSG is the one that we will have for quite a while,” Fleming says. “While we know that further issues may arise, so far the data says that the VFSG reliability is improving.”
As each new version of the VFSG becomes available, airlines face another headache. The VFSGs deliver significantly more power than integrated drive generators on bleed-air systems, but they are also heavier.
“Each component is getting bigger and bigger,” one 787 airline customer says. “The weight of the VFSG is 200lb. It is so difficult to replace.”
Boeing provides tooling, such as slings, to help airline maintenance workers remove heavy equipment. Airlines also have taken more elaborate steps, such as pulling a 787 out of service for 10 days to fix various reliability issues, such as the VSFG, all at the same time. Air India reported to parliament that each aircraft in its fleet was grounded sequentially for a 10-day period between December 2013 and March 2014.
According to Fleming, more weight is one of the trade-offs of the design process. The VFSG units may be heavier than previous kinds of generators, but they replace a much heavier pneumatic power system, which feeds into the aircraft’s overall fuel efficiency.
Other reliability problems have all but disappeared or are being addressed. Earlier this year, Boeing reported that electromechanical actuators for 787 spoilers were one of the two biggest reliability headaches, but the issue was resolved by a recent software update.
“They have already issued a software fix, and we are now installing,” says ANA’s Nishiwaki.
Ethiopian has already installed the new software, and it appears to work. “The spoiler was a problem. Nowadays, we don’t have any spoiler problem,” says chief pilot Hailemariam.
Other systems that once bedevilled the 787 also have been virtually eradicated three years after entry into service.
Hailemariam recalls early days when his pilots would push back from the gate, only to have to return after a spurious message appeared, warning of an inoperative control surface. Most of the time, there was no real issue, only a software bug.
“We changed the flight-control software so many times, maybe three or four times,” he recalls. “Right now I believe we don’t have any such kind of a problem.”
ANA’s Nishiwaki remembers the software problem well. “It is easy to explain,” he said. “Just before the flight, the flightcrew saw some flight-control message in the cockpit, which was a despatch message. In that case, even though they blocked out from the gate, they returned to fix it. But the corrective action is just to apply a ground test for the flight-control systems and clear – no component replacement [was necessary].”
A combination of hardware and software changes finally made the flight-control issues go away, Fleming says. But it also revealed what has become a familiar pattern. As soon as one major issue is retired, another glitch pops upthat was buried one level deeper in the system.
“As we get fixes out, new things come up as components age and the fleet grows,” Fleming says. “There are systems that we’ve come out with a fix and experienced no further problems. There are other systems going through an iterative process to get them to mature.”
The 787 was designed with a “moon-shot” approach to risk tolerance that is no longer welcome at corporate headquarters. It incorporated Boeing’s first mostly composite commercial airframe, a bleedless systems architecture and a new generation of turbofan engine technology to save fuel. At the same time, Boeing attempted to reinvent how it designed and built an aircraft, distributing design authority and production control on a global scale.
The prolonged teething complaints and worse about the 787 are part of the legacy of those decisions made ago, but so is the aircraft’s proven fuel efficiency.
Despite the continued reliability headaches and development setbacks, the 787’s customers remain a remarkably loyal group.
Asked if he thinks Ethiopian would buy the 787-8 if it had to make the decision again, Hailemariam did not hesitate. “Yes, because you get the performance, obviously,” he says. “So it’s just a matter of working through those teething issues.”
The scale of the early challenges left its mark, but yet not a bitter taste for some.
“We were very harmed by this as an airline, but after more than one year of very successful operations I can only say it was worth waiting for, because the customer experienced the efficiency of this aircraft,” says LOT’s Mikosz.
As for Boeing, it still has to work through at least next year to meet customer reliability targets on the 787-8. Meanwhile, it has the 787-10, three versions of the 737 Max and two versions of the 777X already in development. None employ the moon-shot level of risk that Boeing accepted with the 787-8, but that does not mean there will not be challenges.
“I do think we will get better,” says Fleming. “Is it ever going to be perfect? I’m a glass-half-empty guy. We shouldn’t plan on it. We have to plan to be really busy and expect that there will be issues, but work really hard to make sure that we don’t.”
Reporting and writing by Stephen Trimble in Addis Ababa, Seattle and Washington DC. Additional reporting by Greg Waldron in Tokyo, David Kaminski-Morrow in Palma de Mallorca, Oliver Clark in Warsaw and Firdaus Hashim in Singapore.
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Source: Cirium Dashboard