Swiss is cleared to operate a steep approach into London City airport with Bombardier CS100 jets after the manufacturer received Transport Canada and European Aviation Safety Agency approvals on 26 April.

The CS100 will replace Swiss' fleet of BAE Systems 146 regional jets operating to London City from Geneva and Zurich, becoming one of the largest aircraft behind the Airbus A318 to operate in the heavily restricted approach path to the urban centre runway.

The London airport requires aircraft to descend at an approach angle of 5.5 degrees, or nearly twice as steep as a normal glideslope to land for a passenger-carrying transport.

Bombardier tweaked the CS100 flight controls, engine and de-icing system to enable the steep approach certification.

The first step requires the crew to select the London City approach option in the flight management system, says Chuck Ellis, Bombardier's chief test pilot. As the approach begins, the aircraft's fly-by-wire controls automatically raise a couple of the spoiler panels, increasing the drag.

The engine is commanded to run a lower idle setting than normal during the approach. Finally, the environmental control system is programmed to deliver more bleed-air from the engine to the de-icing system on the leading edge of the wings, Ellis says.

Aural and visual alerts on the head-up and flight displays also help the aircrew navigate the steep approach in any weather, he says.

Source: Cirium Dashboard