A Lead Mechanic reported a chronic intercom failure between the front seat pilots and the back seat Medic and Flight Nurse on a Eurocopter AS-350. He also noted the lack of support from his Management to perform proper troubleshooting and pressure to continue deferring the intercom discrepancy.
Synopsis
A Lead Mechanic reported a chronic intercom failure between the front seat pilots and the back seat Medic and Flight Nurse on a Eurocopter AS-350. He also noted the lack of support from his Management to perform proper troubleshooting and pressure to continue deferring the intercom discrepancy.
Narrative
After putting a new aircraft into service we developed an intermittent Intercom Communication System (ICS) issue between the front [pilots] and back seats. The ICS was MEL'd on this date. Troubleshooting was accomplished two days later with the aircraft in-service. Problem could not be duplicated and MEL was removed. ICS failed again five days later and was again MEL'd. Aircraft was taken out of service to troubleshoot the aircraft. Forward ICS panel was replaced the following day; as well as rang-out [electrical] wiring with the assistance of company Avionics support. All wires rang out correctly and issue could not be duplicated during a ground run or flight check. MEL was again cleared. During troubleshooting on the same day; I was asked to defer the maintenance till the next day. I do realize we need to keep our aircraft in service as much as possible to keep our customer happy and keep generating revenue. I am being pressured to put off unscheduled maintenance to a later date. Not only is this just plain wrong; it puts my crew in an unsafe situation. I will NOT compromise the safety of my crew to schedule unforeseen/intermittent problems with the aircraft. I cannot resolve intermittent issues at a convenient time; I have no choice but to troubleshoot the system when it occurs. This system can only be MEL'd for three days and for good reason; it is a system that needs to function correctly to keep communication between the Pilot and Crew open and safety at its highest. The customer must understand that I am doing my best to provide a safe and fully functional aircraft and not dictate when I perform unscheduled maintenance. This will potentially and eventually cause an accident in the future if all maintenance has to be scheduled. I need support to be able to maintain my aircraft in the safest way I can and to not be pressured by the customer to defer maintenance. I have always done my best to keep my aircraft in service as much as possible and to be available at all times. My unscheduled 'Out of Service' time speaks for itself. I maintain my aircraft at the highest level possible and I will not compromise safety for anyone. My crews' lives depend on me doing my job the best I can. If I am being pressured to put maintenance off this is a safety of flight issue and needs to be resolved and soon.
NASA callback
The Reporter stated this was a new Eurocopter AS-350 helicopter with less than fifty hours of operation that developed an intermittent intercom problem that was difficult to duplicate on the ground. The two front seats (pilots) could not talk with the back seat Medic and Flight Nurse. The pilots could talk with each other and the Medic and Nurse could communicate with each other; but not front to back or back to front. Reporter stated the only way for the Medic or Nurse to communicate with the pilots would be for one of them (Medic or Nurse) to stretch their individual headset cord forward to the cockpit and plug into the co-pilot's radio com #2 jack which would then allow one of the back seats to communicate directly with the pilots. But; in that condition; the Medic and Nurse could not communicate with each other.Reporter stated his company installs their own interiors for their air ambulances. Because the problem was intermittent; troubleshooting was difficult. Finally the communication problem became a hard fault. He could not continue to defer the discrepancy again; even though he was heavily pressured to do so. That's when he took the helicopter out of service. Even though he and an Avionics Mechanic had previously 'Rung-Out' the intercom electrical wiring without finding any problems; he (Reporter) went back and started checking for loose connections in the aircraft's belly at the same J-Box connections. There are hundreds of wires with terminal pins at the J-Box area; but since then; after he physically checked the security of those connections; the intercom communication problem has not returned.Reporter also stated that one of his concerns about continuing to defer the communication failure between the pilots and back seat occupants was the importance of all onboard to help the pilot be aware of traffic around the helicopter. During the time the back seat communication was deferred; a Nurse saw an aircraft approach the AS-350 from the aft side and was unable to notify the pilot who had not seen the aircraft.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.