Maintenance Airframe; Maintenance Inspection Authority; Maintenance Powerplant
Maintenance Inspector 5; Maintenance Lead Technician 5; Maintenance Technician 14
Situational Awareness; Time Pressure; Distraction; Fatigue
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Human Factors; Staffing; Company Policy
I removed the Aft Evaporator Blower motor. To gain access; the Tail Rotor Control tube had to be removed.  When the job was finished I asked a Pilot to come and look the job over.  We both missed the bolt that I failed to tighten on the Tail Rotor Control tube. We operate a 24/7 Helicopter Emergency Medical Service (HEMS) operation and are on call 24/5. I feel that pressure from Supervisors to get the job done so we can capture flights affected my performance.  I feel that the pilots are not adequately trained to look over major maintenance such as Flight Controls.  I removed the Aft Evaporator Blower motor. To gain access; the Tail Rotor Control tube had to be removed. When the job was finished I asked a pilot to come and look the job over. We both missed the bolt that I failed to tighten on the Tail Rotor Control tube. We operate a 24/7 Helicopter Emergency Medical Service (HEMS) operation and are on call 24/5. I feel that pressure from supervisors to get the job done so we can capture flights affected my performance. I feel that the pilots are not adequately trained to look over major maintenance such as flight controls being taken loose in places where they don't look on a daily basis. taken loose in places where they don't look on a daily basis.
Reporter stated the Aft Evaporator Blower Motor draws cabin air and also helps cool the Air Conditioning Pack. Replacement was necessary because the motor had quit. Access is through the baggage compartment door; removing an upper panel behind the cabin aft bulkhead where the blower motor is; in an area known as the 'Hell Hole' because of the heat and tight quarters. He had to remove the Tail Rotor Control tube to access the blower motor. The control tubes are inside a 'V' channel.Reporter stated he was sick and fatigued the day he replaced the blower motor and felt he needed someone to look over his work; before he went home early. They are not short staffed on Maintenance personnel. But; a culture has developed at their operation where pilots are called upon by Dispatch to verify the aircraft is mechanically ready for flight; even though pilots do not sign any documents after they reviewed the maintenance work. Maintenance just recently started to add a couple of Quality Assurance (Q/A) items to Mechanic's sign-off. Complacency can be an issue especially if pilot and mechanic are both known to have a good record. Reporter stated the Bell-206L was in for a 300-hour Inspection at one of their regional Maintenance Bases when a Mechanic noticed the loose bolt that secures the Tail Rotor Push-Pull Control tube had not been tightened. The Push-Pull tubes control the pitch of the Tail Rotor via input from the Tail Rotor pedals in the cockpit. The Medi-Vac helicopter had flown about 100-hours in that condition. Their Helicopter Emergency Medical Service (HEMS) operations are a push; push; push environment; including Maintenance. He was separated from the company shortly after the incident.
A Lead Aircraft Maintenance Technician (AMT) was informed he had not tighten one of the bolts that secure the Tail Rotor Control tube on a Bell-206L helicopter after replacing the Aft Evaporator Blower motor. Technician noted that pressure from supervisors to get the job done and the use of pilots to look over major maintenance work accomplished by mechanics were contributors.