All AS350 and AS355 series helicopters fitted with any forward two-place seat.
This Continuing Airworthiness Notice (CAN) alerts operators of affected helicopters of the importance of installing a guard fence between the forward two-place seat and the pilot seat to protect the collective control area from inadvertent damage and/or prevent possible restriction of collective control movement.
The CAA understands that interference with the collective control on affected helicopters is a known issue due to the central cockpit location of the collective control. Most operators of affected helicopters are aware of this safety concern and have installed a guard fence for the collective control area. Some forward two-place seat STCs provide a guard fence as an additional modification to the STC.
This CAN is prompted by an incident reported to the CAA on an AS350 helicopter where the unused seat belt of the forward two-place seat interfered with the collective slide, resulting in an ‘unusual and difficult landing’ due to the belt restricting the collective movement. The operator of the affected helicopter subsequently installed an approved collective guard fence between the forward two-place seat.
Other controls including the fuel shut-off are located in the collective control area and are also prone to inadvertent damage and/or interference from both seat belts and passengers. Forward two-place seats increase the likelihood of inadvertent damage and/or interference, since passengers are seated closer to the collective. Due to the confines of the forward two-place seat, rear passengers are also anecdotally known to kick or potentially rest bags in the collective control area.
The CAA strongly recommends the installation of an approved guard fence between the forward two-place seat and the pilot seat to protect the collective control area from inadvertent damage and/or prevent possible restriction of collective control movement. Operators should also ensure pilots check that unused seat belts are fastened and passenger baggage is properly secured before flight.
