Boeing 787 (partie 2)

787-9 & 787-10X
The optimism on the 787 not only rests on the initial better-than-expected performance of the 787-8, but also lies on the fact that the -8′s better performance gives Boeing more visibility and predictability on the bigger -9 and a future -10X derivative.

For instance, Boeing recently said in a customer presentation slide that early-built 787 from LN10-19 to have a 3% worse block fuel burn than later-built aircraft, instead of the original 6% worse block fuel burn previously cited, according to Aspire Aviation‘s sources at the world’s second-largest aircraft manufacturer.

Lighter parts are a determining factor in reducing the weight of the 787-9 which is considerably more capable than the 787-8 with 40 more passengers yet has a 300nm (nautical miles) longer range.

The 787-8 is starting to benefit from the early availability of redesigned 787-9 parts that help shave the overweight issue of LN66 to less than 2 tonnes (4,409lbs) over its original manufacturer’s empty weight (MEW) target, versus LN1 weighing in at 109.9 tonnes (242,500lbs) in manufacturer’s empty weight (MEW), 9.75t (21,500lbs) over target of 221,000lbs whereas LN7 and LN20 are 6.1t (13,500lbs) and 3.99t (8,800lbs) overweight, respectively, the same sources say. LN90 is on track to be the first production example meeting the original manufacturer’s empty weight (MEW) and airline-specific operating empty weight (OEW) targets.

Other weight improvements on the 787-9 include Spirit AeroSystems’ one-piece cockpit window frame that will eliminate around 200 fasteners and reduce the cockpit structure’s weight by 100lbs, as well as an elimination of side-of-body modification which saves 363kg (800lbs) in weight as the two titanium fittings installed on the upper and lower sides of each 787 wing are held together by numerous fasteners, thereby compounding the weight penalty of the fix.

The weight savings that are going to be achieved on the 787-9 have bolstered Boeing’s confidence as it moves the first 787-9 example, dubbed ZB001, from LN139 to LN126 and that the 787-9′s manufacturer’s empty weight (MEW) is 2% lighter than expected, although Boeing still sticks to the original MEW target, according to Aspire Aviation‘s multiple sources at Boeing.

Meanwhile, engine improvements are also another core pillar in making the 787-9 more fuel efficient than the -8, as the former burns 2.4 litres of fuel per passenger per 100 kilometres whereas the latter burns 2.6L per passenger per 100km.

Derby, England-based engine-maker Rolls-Royce is introducing the Trent 1000-TEN (Thrust Effciency New Technology) which will reduce engine specific fuel consumption (SFC) by 3% from Trent 1000 Package B standard, which missed its original SFC targets by 2%. In comparison, the Package A engine missed its original SFC target by 4.3%.

“We are confident the TEN is better than our competition,” Rolls-Royce vice president (VP) in strategic marketing Robert Nuttall claimed.

The 76,000lbs engine will be around 1% better than its original SFC at best and will incorporate design features from the Trent XWB such as rising line intermediate pressure compressor (IPC) and blisks in the first 3 stages of the high pressure compressor (HPC).

In contrast, the General Electric GEnx-1B engine has missed its original SFC target by 2.7%, with performance improvement packages PIP1 and PIP2 clawing back 1.6% and another 1% of fuel efficiency, respectively, of which GE said the PIP1 has exceeded its original expectations.

These engine improvements and significant weight savings introduced on the 787-9, not only will make the 280-seat 6.09m (20ft) stretch aircraft with an 8,050nm range and a 250.8 tonnes (553,000 lbs) maximum take-off weight (MTOW) much more capable than the 787-8, it also bodes well for the development of a double-stretched 787-10X derivative.

The 323-seat 787-10X aircraft will have the same MTOW as the -9, along with a same wingspan at 60.1m (197ft), despite being 5.49m (18ft) longer with a 4 frames stretch in aft-body fuselage and a 5 frames stretch in forward fuselage.

Its range would be 6,750nm for aircraft powered by Rolls-Royce Trent 1000-TEN engines or 6,700nm with the GEnx-1B engine and has a maximum landing weight (MLW) of 445,000lbs and a maximum zero fuel weight (MZFW) of 425,000lbs.


The 787-10X will be a highly fuel efficient medium-haul airplane with a 25% lower block fuel burn than an Airbus A330-300, as well as a 10% and 5% lower operating cost than the A350-900 and -1000, respectively; although Airbus conceded that the cash operating cost (COC) per seat of a 300-seat A330-300 is only 1% and 6% higher than the 787-8 and -9, respectively, and claimed the direct operating cost (DOC) of an A330-300 being 10% lower than the 787-8 and 4% lower than the 787-9 (“Airbus is right on A330 improvement strategy“, 10th Jul, 12).

Interestingly, while Boeing says the 787-10X will not enter service until the end of this decade and will not be launched by the end of this year, Aspire Aviation‘s sources at Boeing are still indicating progress on the double-stretched airframe with a recently determined manufacturer’s empty weight (MEW) of 119.5 tonnes (263,452lbs) in a 323-seat configuration

The 787-9 is one giant step closer to reality. Major assembly on the first airplane is now underway. Things kicked off on time when Boeing partner Kawasaki Heavy Industries began installing passenger door frames in the forward midbody fuselage.

When complete, that section will hitch a ride on the Dreamlifter to North Charleston where the Boeing South Carolina team will integrate it with other 787 structures. Final assembly will take place in Everett in 2013. First flight of the 787-9 is still set for 2013 and first delivery in 2014.

ANA 787 suffers hydraulic leak before takeoff.

The world's first operational Boeing 787 was forced to return to the gate at Okayama after a leak in a hydraulic pump located in its port-side engine nacelle.

The All Nippon Airways (ANA) 787, bearing registration JA801A, was taxiing before take-off on the Okayama-Tokyo route this morning when the pump failed, ANA said.

The issue came to the pilots' attention when cockpit instruments alerted them to a rapid hydraulic pressure fall. They shut down the port-side engine and taxied to a gate using the aircraft's starboard engine.

A Rolls Royce spokesman clarified that the pump is not part of the Trent 1000, though the engine drives the pump.

There were 88 passengers, six cabin crew and two pilots aboard at the time of the incident. All disembarked safely via an air bridge.

Media reports from Japan suggested that white smoke was seen coming from the engine. ANA attributed this to the heating of engine parts near the pump leakage.

On 22 July, ANA grounded five of its 11 Boeing 787s after the airframer notified the carrier of a possible gearbox defect in the Trent 1000 engine.

All five aircraft returned to service within days after gearbox supplier Hamilton Sundstrand shipped replacement parts to ANA.

http://www.flightglobal.com/news/articles/ana-787-suffers-hydraulic-leak-before-takeoff-376086/