Goodrich and Messier-Bugatti have been selected as rival suppliers of electric braking systems for the Boeing 7E7, the first large commercial aircraft to use electrics in place of hydraulics for brake actuation.
Wheels and brakes are among several new 7E7 supplier selections, including Latecoere for the passenger doors and two US divisions of another French company, Zodiac Groupe, for the aircraft's water and waste system (Monogram Systems) and escape slides (Air Cruisers).
Goodrich and Messier-Bugatti will supply electric braking systems comprising the aircraft wheels, electromechanically actuated carbon brakes and the electronics that drive the digitally controlled brakes. There are eight main wheels and brakes and four controllers per aircraft.
The benefits of electrics over hydraulics for braking include reduced weight, increased modularity, easier assembly, more precise control, higher reliability and improved maintenance through information available digitally from the brakes, says Rob Brundrett, Goodrich director of brake control systems design and development. This includes the ability to sense brake wear for the first time, he says.
Pre-integrated modules will reduce assembly time and cost and allow "on-wing" replacement, and the aircraft will be able to monitor brake health, says Brundrett. The first application of electric brakes is Northrop Grumman's Global Hawk unmanned air vehicle, for which Goodrich is supplying the system.
Snecma subsidiary Messier-Bugatti, Latecoere and Zodiac are the latest French suppliers named to the 7E7 programme. The others include Snecma companies Messier-Dowty (nose landing gear) and Labinal (wiring), and Thales (electrical power conversion system and integrated standby flight displays).
Meanwhile, Boeing Wichita has leased two automated fibre-placement machines from neighbouring Raytheon Aircraft to test manufacturing technology for the 7E7's composite forward fuselage.
GRAHAM WARWICK / WASHINGTON DC
Source: Flight International
