unmanned transport
4th Jan 2006, 02:21
Jan 2/06
Boeing.
Boeing expects to begin flight tests in January of a short-field performance
enhancement package for the 737 Next Generation family, which is expected to markedly reduce take-off and landing runs or significantly increase payload
performance.
Launched initially to enable the Brazilian carrier GOL to operate larger
737-800s into the restricted 1,465m (4,800ft)-long runway of Rio de Janeiro’s
Santos Dumont airport, various elements of the package are expected to offer
benefits across the entire range of Next Generation models, says 737 chief
project engineer Mike Delaney.
The improvements could apply to operators flying into “places like Florence,
London City, the Faroe Islands and several areas in Japan”, says Delaney.
The enhancement package consists of elements that can be applied to the
longer-body -800/900ER models as well as a wider set of improvements that can be offered for other family members. Specific to the -800/900ER are sealed slats for all take-off flap positions, and a two-position tailskid. On current aircraft, the slats are sealed for take-off flap positions 1° and 5°, and are gapped for 10°, 15°, 25° and over. The change will see the sealed positions extend through 25° flap.
Next Generation generic configuration changes include Krueger flap seal
actuation to allow the device to be “left sealed for take-off and up out of the
way [open] for approach and landing,” says Delaney.
Flight spoiler deflection on the ground will also be increased from 30°, to
match the maximum 60° of the ground spoilers. The operation of the flight
spoilers in normal flight will be unchanged, he says. “But when it lands all the
spoilers will come up to a nominal 60° throw for greater braking performance.”
Another subtle change across all models will be a reduction in the camber, or
“splay” of the main landing gear. “We’ve brought it in by just over 1°, which
increases the uniformity of braking across all four brakes and will help tyre
[wear] issues we’ve seen across the fleet. It’s a maintenance benefit.”
Also changing will be the engine idle-thrust delay time, which is being
reduced from 5s to 2s. The change, effected through the CFM International
CFM56-7B’s full authority digital engine control, will “bring forward idle
thrust off the aircraft faster”, thereby helping shorten the landing roll.
The Krueger flap change is applicable to all models and will boost landing
performance, as will the idle thrust delay change. The increased flight spoiler
deflection, also applicable across all models, will improve both take-off and
landing. The -800/900ER specific changes will boost take-off performance in the case of the leading-edge slat seal change, and landing performance in the case of the two-position tailskid.
Boeing expects the package to reduce the typical landing run of a
winglet-equipped -800 by up to 100m, or increase the landing weight by as much as 4,730kg (10,400lb); while the take-off length could be reduced by more than 70m or the take-off weight performance boosted by more than 1,710kg.
The three-month flight-test effort is expected to run from late January
through to late April, with the delivery of the first fully equipped aircraft
due around mid-June 2006.
Boeing.
Boeing expects to begin flight tests in January of a short-field performance
enhancement package for the 737 Next Generation family, which is expected to markedly reduce take-off and landing runs or significantly increase payload
performance.
Launched initially to enable the Brazilian carrier GOL to operate larger
737-800s into the restricted 1,465m (4,800ft)-long runway of Rio de Janeiro’s
Santos Dumont airport, various elements of the package are expected to offer
benefits across the entire range of Next Generation models, says 737 chief
project engineer Mike Delaney.
The improvements could apply to operators flying into “places like Florence,
London City, the Faroe Islands and several areas in Japan”, says Delaney.
The enhancement package consists of elements that can be applied to the
longer-body -800/900ER models as well as a wider set of improvements that can be offered for other family members. Specific to the -800/900ER are sealed slats for all take-off flap positions, and a two-position tailskid. On current aircraft, the slats are sealed for take-off flap positions 1° and 5°, and are gapped for 10°, 15°, 25° and over. The change will see the sealed positions extend through 25° flap.
Next Generation generic configuration changes include Krueger flap seal
actuation to allow the device to be “left sealed for take-off and up out of the
way [open] for approach and landing,” says Delaney.
Flight spoiler deflection on the ground will also be increased from 30°, to
match the maximum 60° of the ground spoilers. The operation of the flight
spoilers in normal flight will be unchanged, he says. “But when it lands all the
spoilers will come up to a nominal 60° throw for greater braking performance.”
Another subtle change across all models will be a reduction in the camber, or
“splay” of the main landing gear. “We’ve brought it in by just over 1°, which
increases the uniformity of braking across all four brakes and will help tyre
[wear] issues we’ve seen across the fleet. It’s a maintenance benefit.”
Also changing will be the engine idle-thrust delay time, which is being
reduced from 5s to 2s. The change, effected through the CFM International
CFM56-7B’s full authority digital engine control, will “bring forward idle
thrust off the aircraft faster”, thereby helping shorten the landing roll.
The Krueger flap change is applicable to all models and will boost landing
performance, as will the idle thrust delay change. The increased flight spoiler
deflection, also applicable across all models, will improve both take-off and
landing. The -800/900ER specific changes will boost take-off performance in the case of the leading-edge slat seal change, and landing performance in the case of the two-position tailskid.
Boeing expects the package to reduce the typical landing run of a
winglet-equipped -800 by up to 100m, or increase the landing weight by as much as 4,730kg (10,400lb); while the take-off length could be reduced by more than 70m or the take-off weight performance boosted by more than 1,710kg.
The three-month flight-test effort is expected to run from late January
through to late April, with the delivery of the first fully equipped aircraft
due around mid-June 2006.