GUY NORRIS / LOS ANGELES
Project designed to demonstrate new safety features to Chinese airlines and help to overcome landing risks
Boeing engineers are developing a highly accurate simulation of narrow Tibetan valleys to help demonstrate the enhanced safety of new 737 flightdeck displays as part of a sales drive to the newly consolidated China National Aviation (CNAC) holding company.
Boeing believes the demonstration of a suite of advanced display features could give it the edge in an emerging competition which pits the 737 against the Airbus A320 family. Developed on Boeing's 737-900 technology demonstrator, the suite includes integrated approach navigation (IAN), the vertical situation display (VSD) feature and the quiet climb system (QCS).
IAN is an upgrade of the flight- management computer which provides instrument landing system-like procedures for FMC approaches. The VSD works with the enhanced ground proximity warning system to provide a profile view of the projected flight path and associated terrain features, while the QCS allows the auto-throttle to reduce thrust to a climb gradient of 1.2%.
"We're talking to the Chinese about all three features," says Boeing product marketing regional director Kenneth Hiebert, who adds that the Civil Aviation Administration of China is co-operating with the demonstration.
CNAC, the parent of Zhejiang Airlines, merged with Air China last year as part of a government-ordered consolidation programme for the industry. The group also acquired China Southwest Airlines, which operates regular services to Tibet.
The simulation will focus on a high-fidelity representation of the precipitous terrain around Bangda and the Tibetan capital of Lhasa. Bangda, which has one of the world's longest runways at 5,500m (18,000ft), is on the west flank of the Taniantaweng mountain range at an elevation of 14,200ft, midway between Lhasa and Chengdu in the neighbouring province of Sichuan.
Lhasa's Gongga Airport is the third highest in the world at an altitude of 11,600ft. Flights to the region from Chengdu are forced back around 40% of the time, says Hiebert, who adds: "We'd like to get them down to below a 10% diversion rate."
The simulated terrain, modelled using satellite imagery, will be sufficiently accurate to fly with a required navigation performance of 0.28km (0.15nm).
"That will give us the required approach and departure tolerances and will be the first time RNAV approaches into Tibet will be performed using these minimums," says Hiebert.
Source: Flight International
