EAD 30/1/14 PZL SW-4 helicopters
 

Reference: EASA AD 2014-0029-E

Title: PZL SW-4 helicopters: Rotor Flight Controls – Collective Control Lever Electrical Harness Attachment – Modification

Description: EASA EMERGENCY AIRWORTHINESS DIRECTIVE

http://www.caa.co.uk/docs/33/2014013...D20140029E.pdf

Jammed collective in flight.

Investigation determined that the collective lever jamming was caused by the T7 electrical harness, which had been displaced due to improper attachment and was interfering with surrounding elements. The T7 electrical harness is conducted from the collective lever grip into the collective lever tube, with its extension attached to control system components on the cockpit floor. A helicopter may be fitted with single or optionally dual controls. Each collective lever has its own T7 electrical harness.

This condition, if not corrected, could result in jamming of the collective control lever and consequent loss of control of the helicopter.