David Learmount/LONDONGuy Norris/Los Angeles
Boeing is in line to win the battle for European approval of Next Generation 737 high-density seating without meeting the formal Joint Aviation Requirements (JAR) specification for emergency-exit configuration.
The European Joint Aviation Authorities (JAA) is satisfied with Boeing's latest proposal and is putting it forward for consideration by the JAA Board, which could decide early in August.
The new 737-700 and -800 are restricted by JARs to carrying fewer passengers than their capacity because their Type III emergency overwing exits do not con- form to the latest regulations. The JAA, unlike the US Federal Aviation Administration, has denied Boeing "grandfather rights" on its Next Generation 737.
Approval is vital to Boeing, as it has contracted with the 737-800's launch customer, Hapag-Lloyd, and up to six other European carriers to provide 189-seat capacity - nine more seats than on the rival Airbus A320. The -800, the first of which was rolled out on 30 June, is now restricted to 180 passengers.
The JAA has recommended Boeing's latest proposal for improved Type III exits for approval, putting it forward for "limited consultation" with industry and foreign regulators.
Boeing's new Type III exit incorporates a new, automatic, fast-opening hatch which can be operated by any passenger and is ready for evacuation within 3s of actuation, compared with the 13s allowed under the new regulations, says JAA regulation director Yves Morier. The JAA argument is basically that the 10s saved makes the exit equivalent in safety to that of the larger exit apertures required on newer designs such as the A320.
Boeing says that the new design combines the standard "plug"-type-door features of the current design, with the new capability of automatically opening a clear exit. The door is hinged along the upper edge, and the opening sequence begins with the door moving inwards at the top when the emergency exit handle is pulled, explains Boeing. The handle is linked to a cam arrangement, which rotates the door inwards to clear the plug stops. The door then moves down to clear the lower plug stops before rotating on springs out and up.
The handle mechanism can be activated from seat rows forward and aft of the exit row and from the middle and window seat of the exit row itself.
Source: Flight International
