AAIB investigation to Gulfstream 550, HZ-A6
Collision with ILS aerials whilst on approach to Runway 22 at London Stansted Airport, on 10 December 2013.
The aircraft was carrying out a charter flight from Riyadh in Saudi Arabia to London Stansted Airport. It was radar vectored for a CAT I, ILS DME approach to Runway 22 at Stansted with the autopilot (AP) and autothrust (AT) engaged. Conditions at the time were below the CAT I approach minima. With the aircraft fully established on the approach, the AP and AT were disengaged at 1,600 ft aal and the aircraft was hand flown by the commander for the remainder of the approach and landing. The localiser was maintained, but the aircraft flew above the glidepath before descending through it. For reasons that could not be established, go-around mode was selected, which would have inhibited the EGPWS glideslope warnings. In the final stages of the approach the aircraft was well below the glideslope, causing it to strike the Runway 22 ILS localiser monitor aerial and the Runway 04 localiser aerial array, before touching down short of the Runway 22 threshold.
The accident occurred as a result of the pilot continuing to land from a destabilised approach, rather than performing a go-around.