2009-07 · NASA ASRS report 844087
Two Lead Mechanics and one Avionics's Mechanic Technician report on their involvement with an Operational Check of a B767-300 Hydraulic Motor Generator (HMG). Procedure requires both engines to be running at flight idle and then moving the gear handle to the 'up' position. Nose Gear collapsed; causing serious fuselage damage. Nose Landing Gear pin not installed.
Aircraft was damaged while sitting on the ramp outside hangar. I was in right seat checking a EFIS Control Panel operation when the Lead Mechanic; (I'm avionics); came on board with a Lead Specialist. What test was being conducted; was unknown to me. Lead Mechanic in left seat did a start on both engines and pressurized hydraulics. At this point he directed me to place the gear lever in the 'up' position. Knowing the kind of damage that could occur; I stopped at the gear handle 'mid' position and asked him if he was sure; if the pins were installed in the gear. He hesitated and I returned the handle to the 'down and locked position.' He leaned out the Captain's window and communicated with the ground person through hand signs to confirm that the pins were installed. I was informed by the Lead Mechanic and the Lead Specialist; that the pins were installed and it was safe to move the handle to the 'up' position. At this point I did as requested and the Nose Gear of the aircraft collapsed. The Lead Mechanic's comment was that the pins were 'not properly installed.' No one in the cockpit was able to exit the aircraft and check the pins before incident occurred; as the doors were all closed and steps pulled away Never run engines; or operate parts of the aircraft; without establishing positive communications by patch cord through the interphone system. If noise levels allow; radios may be substituted. Hand signals should be used only as a last resort and then only established signals used. Unclear or ambiguous instructions should be cause to cease activities until all parties are clear on what is to occur. Clear communication not established between cockpit and ground.
We were tasked to do an engine run that involved performing an Operational Check to the Hydraulic Motor Generator (HMG). We first cleared the area and told Ground Support to install gear pins. After Ground Support returned with gear pins and walked under the aircraft to return to the left hand side of the aircraft in view of the cockpit; I assumed the pins we installed and was cleared to start engines. After engines were running we put the aircraft in Flight Simulation Mode to start the HMG test; which required the cockpit personnel to move the gear handle to the 'up' position and that was when we discovered the nose gear pin had not been installed. The aircraft went nose down and damage occurred. Better communication; check and double check all procedures are followed. Poor communication between cockpit and Ground Support; not familiar with task; trying to get task done in efficient time.CALLBACKReporter stated the B767-300 just finished a heavy check. He was in the left seat and they were running engines as part of a check to simulate the aircraft was in the Air Mode and verify the hydraulic motor generator (HMG) would operate with the engines at flight idle; pull the circuit breaker; move the gear handle to the 'up' position and take the engine generators 'off-Line.' The battery discharge light should illuminate; indicating the battery is discharging. A relay should close and the hydraulic motor generator should be operating and supplying electrical power.Reporter stated they are changing their engine run communication procedures; to require a hard wire headset must be used and connected through the aircraft interphone system whenever the engines are running.
More incidents for this aircraft family
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.
Loading the flight search…
Pick an aircraft model — Boeing 737, Airbus A320, A380, Boeing 787 Dreamliner and more — enter your origin airport, and FlightFinder shows every route that plane flies from there with live fares.
We support Boeing 737/747/757/767/777/787, the full Airbus A220/A319/A320/A321/A330/A340/A350/A380 family, Embraer E170/E175/E190/E195, Bombardier CRJ and Dash 8, and the ATR 42/72 turboprops.
Search and schedules are free. Pro ($4.99/month, $39/year, or $99 one-time lifetime) unlocks the enriched flight card — on-time stats, CO₂ per passenger, amenities, live gate & weather — plus My Trips with push alerts.
Live schedules come from Amadeus, AeroDataBox and Travelpayouts. Observed routes (which aircraft actually flew a given city pair) are crowdsourced from adsb.lol ADS-B data under the Open Database License.