Boeing 747-8F et I

Boeing poised for crucial phase in 747-8 test effort
By Max Kingsley-Jones

Boeing is approaching a crucial phase in the 747-8 flight-test effort as it prepares to start trials of the -8I passenger variant and undertakes the dramatic maximum-brake-energy demonstration on the freighter version. It is also awaiting the analysis of back-to-back wake vortex testing, which will determine whether the stretched 747 will be approved in the same separation category as the smaller 747-400.

Four 747-8Fs are engaged in the flight-test programme, which began on 9 February 2010. "We've flown more than 600 flights and 1,600h so far," said Boeing Commercial Airplanes chief test pilot Capt Frank Santoni, addressing the Royal Aeronautical Society in London this week. "We'll start to fly the [-8I] Intercontinental test airplanes in the next couple of months."
Santoni says that Boeing will be able to leverage much of the testing carried out with the -8F for the -8I effort, in areas such as the engines and brakes. 747-8F certification is due later this year, and a key test that has been completed is the Vmu (minimum unstick speed) trial. In this, during take-offs, a wooden block is attached to the tail and is is deliberately dragged along the ground to determine the slowest flying speed. Close to 1,000 stalls have also been flown, adds Santoni. This test will not need to be re-run with the -8I.

Stall tests are now being flown with artificial ice shapes installed on the leading edges of the wing, tailplane and fin. "We're also doing the flight-loads survey - this is a big test where we put a lot of 'gs' on the airplane in different flap configurations to ensure the wing loads are correct," he adds.

The US Federal Aviation Administration is now "on board" 747-8 flights for certification tests, and within the next month the maximum brake energy test is due to be carried out.

"This will be done at the highest maximum take-off weight - 975,000lb [442,650kg] - with the take-off rejected at a yet-to-be-determined speed but it will be in the 180-185kt [333-342km/h] region," says Santoni.
To determine whether the 747-8's wake vortex is significantly different to a 747-400, back-to-back trials have been flown at Fresno, California using a lidar (light detection and ranging) system that measured the strength of the vortex as each aircraft passed down the glideslope, says Santoni. "The data is still being analysed, but the hope is that there will not be a significant difference so the 747-8 will be approved for the same separation requirements that we have today for the 747-400."

Airbus has flown a series of similar back-to-back trials comparing the A380 with other large widebody types, including the 747-400, to help determine the double-decker's separation requirements, which has its own wake category.

http://www.flightglobal.com/articles/2011/02/02/352670/video-boeing-poised-for-crucial-phase-in-747-8-test-effort.html

Lufthansa discloses 747-8I configuration
By Jon Ostrower
Lufthansa plans a 386-seat configuration of its new 747-8I when it arrives in its fleet in first quarter of 2012.

The stretched jumbo jet will be configured with eight first class seats, 80 business class seats and 386 economy seats.Nico
Buchholz, executive vice president, Lufthansa Group Fleet Management,
says the carrier plans a new on-board product, which altered the
available space on the aircraft.

"We started with slightly above 400 [seats], but that was the old
standard, things evolve," he says, "We find things which we can do to
the passengers - which are positive - and this usually does cost a
couple of seats."

Details of the new on-board product were not disclosed.Positioned
between the 526-seat A380 and twin configuration 306- and 345-seat
A340-600, the 747-8I will occupy a space that will allow the carrier to
begin partly replacing its 23 747-400s and seven -400 Combis.

Nico Buchholz says no timeline for the fleet's retirement has been
identified, though market requirements will dictate the pace of the
747-400s' exit from the fleet.

Additionally, final route selection has not yet been determined, adds Buchholz, though he says any of the
carrier's roughly 45 long-haul destinations are candidates.

Rumored excess weight and engine fuel consumption shortfall on the 747-8I
notwithstanding, Buchholz says the new jumbo will be able to meet the
carrier's requirements."

All the mission profiles we want, we can meet," says Buchholz, "And actually we have very onerous points where we
look for mission profiles, sometimes routes we don't fly, but we
pinpoint certain areas to find if there are any weaknesses, and then we
are extremely pleased when we don't find them. And I'm stil pleased."

Buchholz anticipates a performance improvement package in the years to come and
says they will have no operational impact on the aircraft "except we may
save a little bit of fuel," he says.

The first 747-8I is slated to fly in the "early spring" - late March or April - and is expected to
be certified in the third or fourth quarter following a 600h flight test
campaign.

A total of 33 747-8I aircraft have been ordered, with
Lufthansa accounting for the bulk of the backlog with 20. Korean Air
holds orders for five of the aircraft, along with eight slated to be
configured for head of state and VIP missions.

http://www.flightglobal.com/articles/2011/02/13/353111/lufthansa-discloses-747-8i-configuration.html