Safety action has been taken after the nose wheel of an offshore helicopter failed to operate on landing.
An Air Accidents Investigation Branch (AAIB) report on the incident at Scatsta Airport on Shetland in January found no-one was injured but the nose landing gear (NLG) had to be lowered manually by ground staff before the helicopter could land.
The Sikorsky helicopter was returning from the Magnus offshore platform with 19 passengers and two crew at the time.
It was found that the automatic nose wheel self-centring mechanism had not operated, causing the nose wheels to jam in their bay.
The crew sought advice from engineers over the radio and then hovered the helicopter over the runway apron, with its back wheels on the ground and nose held in the air.
An engineer then checked the NLG and released it with a lever, allowing the helicopter to ground fully.
Passengers were briefed before the manoeuvre and emergency services were on standby throughout.
The cause of the failure was not determined but the operator has taken three safety actions, including updated guidance for engineers and a review of emergency operations procedures, the AAIB said.
The helicopter was removed from service and the NLG replaced.
The AAIB report said: “The exact cause of the failure of the NLG to centre the nose wheels during retraction could not be determined. However, the operator has taken steps to inform its staff of a potential cause identified in previous cases by the manufacturer.
“The incident has also highlighted a discontinuity in the operator’s emergency procedures, which have also been addressed.”