B747-400 flight crew reported after arriving at the gate; the Marshaller gave the chocks in hand signal to them. The Captain released the parking brake and noticed the aircraft was rolling back. After the parking brake was reset; a tug was called to reposition the aircraft. Wheel chocks had never been put in place.
Synopsis
B747-400 flight crew reported after arriving at the gate; the Marshaller gave the chocks in hand signal to them. The Captain released the parking brake and noticed the aircraft was rolling back. After the parking brake was reset; a tug was called to reposition the aircraft. Wheel chocks had never been put in place.
Narrative
The flight proceeded normally from ZZZZ1 to ZZZZ. For this leg I was PM and the Captain was Pilot flying (PF). Landing and taxi in was normal. We were guided by a 'Follow Me' vehicle to park; a jet bridge equipped parking spot at the terminal. As we approached the parking spot; we identified the Military Marshaller with wands standing on a set of stairs leading up to the terminal. This position put the Marshaller off to the left of the nose of the airplane; rather than in line with the parking line as is usual at most parking spots. Because of the Marshaller's position; I lost sight of them for the final 10 or so feet of the taxi in. I never saw them again after this point. The Captain stopped the aircraft; and applied the parking brake as normal. I began my shutdown flow; transferred power the APU and configured the Hydraulic Panel. The Captain shutdown the engines; and I turned off the seat belt signs. While completing the rest of my flow; the Captain received the 'Chocks In' signal from the Marshaller and released the parking brake. The Captain called for the Shutdown checklist.Shortly after starting the checklist; while still 'heads down'; I became aware of the sensation of movement and the Captain immediately applied the brakes. Captain had been 'heads up' and had noticed the movement; as well as signals from the Ground Crew; before I did and thus was able to apply corrective active quickly. I ensured that the Hyd #4 was in the AUX position; that Hydraulic pressure was adequate and turned the Seat Belt Signs back to ON. The Captain made a PA informing the passengers and crew to remain seated while we waited for a tug to pull us back into position. While waiting for the tug; the Company Mechanic plugged their headset in; and informed us that they had been behind the nose wheel installing a gear pin when the aircraft began to roll. The aircraft had rolled straight back approximately 9 meters. The Captain explained to them that the Marshaller had given the 'Chocks In' signal. The Mechanic then went to have a discussion with the Marshaller off-headset. The Mechanic returned to us; noticeably shaken and angry; and explained that the Marshaller admitted to giving us the 'Chocks In' signal; but thought that it indicated that they were in the process of placing the chocks; not that they were in place. This is an interpretation of that hand signal that I've never seen before and believe to be incorrect even on military fields. The aircraft was pulled forward; and secured with positive headset communication with our Mechanic. No injuries were reported; and an inspection by myself and maintenance staff indicated no damage as a result. The Marshaller left before either I or the Captain could speak to them; and so no debrief was possible. Incorrect usage of hand signals lead to the release of the parking brake before the wheel chocks were in place. Proper training of Marshals; to include differences between Military and Civilian hand signals (where any exist) is critical. Additionally; having a Ground Staff member plug into the interphone system as early as possible after stopping would provide a clearer means of communication than hand signals. Possibly an adjustment to ground staff procedures could be made so that the Mechanic should wait until after the chocks are in place before standing behind the nose gear to install pins. Finally; ensuring that at least one Crew Member is 'heads up' (as the Captain was in this situation) will provide an extra layer of safety; especially during the busy period immediately after parking where the FO is 'heads down' conducting shutdown flows and checklists.
Second reporter narrative
While operating Aircraft X; ZZZZ1 to ZZZZ; we had a completely uneventful flight up until it came time to park the aircraft. I was the Pilot Flying. We were marshalled into the gate by a Military Marshaller who was standing halfway up the stairs near the jet way at an elevation a little less than the flight deck level. He was at a 10 o'clock position and we were both visible to each other but not necessarily fully visible to the First Officer (FO). Everything went smoothly. We taxied forward slowly. The Marshaller slowly crossed their wands and the aircraft was brought to a stop. The parking brake was set. The Marshaller then turned away and proceeded down the stairs to ground level. The First Officer switched the power over to the APU and the engines were shut down. The hydraulics were switched per normal procedures. #4 to AUX and 1;2;3 to OFF. Proper flows were completed.I looked back outside. The local Company Mechanic was approaching the aircraft. They did not have a headset with them. I looked at the Marshaller; who was now on the ground at a 10 o'clock position. They put his two wands together 'tip to tip' in front of them; universal for indicating the 'chocks were in place'. I gave them a thumbs up and they signaled back with a thumbs up. The brakes were then released with no aircraft movement. The seat belt sign was then selected off. I called for the shutdown checklist and the FO and I commenced it. I glanced up and noticed movement. The aircraft was slowly rolling backwards away from the gate. The Marshaller was frantically crossing their arms. I immediately pressed the toe brakes quickly stopping the aircraft and reset the parking brake. Later; according to the Mechanic; the aircraft rolled about 3 meters. The chocks were not in place; contrary to the Marshaller's hand signals.I made a PA for everyone to remain seated as we now had to be towed back in. The Mechanic was then observed going back to his truck to get their headset and returned to the aircraft and plugged in. They stated that they were almost run over while placing the bypass pin in and that they also observed the same incorrect signals from the Marshaller and was able to get out of the way in time. They then had an angry confrontation with the Marshaller over it. They reported to me that the Marshaller argued with him that 'they park aircraft all the time this way and that the placing of the wands 'tip to tip' in front was 'asking me if I WANTED chocks''. This is not a way to deliver a question. And when do we ever NOT chock an aircraft? Never; in three decades of professional flying; have I ever seen the universal signal of wands tip to tip indicate anything other than 'chocks in place'. They should have remained visible on the stairs with their wands crossed; hold position; until the chocks were confirmed in place. The aircraft was then towed back into position and properly chocked. No injuries were reported and the passengers disembarked. The Mechanic came to the flight deck and was visibly angry. They were furious at the Marshaller. The Marshaller drove away and could not be found; as I wished to speak with them as well.
More incidents for this aircraft family →
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.