Date: 201205
Local time of day: 0001-0600
Location: ZZZ.Airport, US
Aircraft: B757-200
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground ZZZ
Aircraft component: Nosewheel Steering
Component problem: Improperly Operated
Reporter organization: Air Carrier
Reporter function: Captain; Check Pilot; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Other / Unknown
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: Taxi
Result: General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Aircraft; Procedure; Human Factors
Primary problem: Human Factors

Narrative: After completing the pushback we received the 'aircraft clear' and 'salute' hand signals. After requesting and receiving clearance to taxi; I added power to proceed. The initial taxi was straight ahead and I therefore did not have to make inputs to the nose wheel tiller. However; at the first attempt to steer the aircraft; I realized that I had no authority with the Captain's tiller. I immediately stopped the aircraft and First Officer advised Ground Control that we needed to have Maintenance assistance before moving. I also asked First Officer to contact Operations and ask for someone to come out to our location and inspect the steering system. I was reasonably confident that the push crew had simply forgotten to reset the steering bypass lever. After a few minutes a ramp person arrived aboard a small baggage cart. He dismounted and then proceeded under the aircraft. He did not have a headset; yet apparently moved the bypass valve. I felt the nose wheel center while he was under the aircraft. The man subsequently reappeared from under the aircraft; got on his cart and departed. There were no hand signals or communication concerning the final status of his inspections. He just simply drove away! Not knowing the status of the repairs; we called operations and asked for qualified mechanics to come out and inspect the gear assembly and report the status to us. Three mechanics eventually arrived in two vehicles. I flashed the taxi light three times to indicate that the parking brake was set. Communication was established and they asked that I exercise the steering mechanism. It was established that the system was working normally and that the valve was likely not well seated on the initial pushback. After disconnecting the headset; the three mechanics boarded their vehicles and departed. Unfortunately; they also did not render an 'aircraft clear' or 'salute' signal to indicate that it was safe to taxi. We were left to ponder if there were unaccounted for personnel left below the aircraft. In the interest of safety we again called operations to assure that all ramp and maintenance personnel had vacated and were not at safety risk. I am of the opinion that the personnel non-compliance with FOM or pushback safety guidance posed a potential for serious personnel injury. The initial steering bypass problem was effectively a routine error that was easily resolved by stopping the aircraft and seeking assistance. However; the failure of four ramp staff (three mechanics and one ramp) to follow established protocols for safely approaching an aircraft with the operating engines should be addressed. Their very lives could eventually be at stake.




Synopsis: B757 Captain discovers that nose wheel steering is not functioning shortly after being cleared to taxi and calls for assistance. A ramp person arrives and apparently moves the steering bypass lever rendering the steering operational and departs without communicating with the Captain. Maintenance is called and three Mechanics arrive and verify the bypass lever is properly positioned then depart without signaling clear.