Pre Flight External Check by Fight Crew is part of the basis for the Captain's Aircraft Acceptance which must be formally recorded in the Aircraft Technical Log prior to every flight departure. It is primarily, therefore, a general visual inspection of those aspects of fitness of the aircraft for flight which can be verified wholly or partly in that way. Incidentally it also provides an opportunity to observe the environment in which the aircraft is parked and may sometimes allow the observation of aspects of aircraft hold loading and routine aircraft servicing. It is entirely unrelated to the separate requirements for appropriately qualified aircraft maintenance technicians to carry out scheduled checks and inspections necessary for the Certificate of Release to Service to be signed and, in some cases, to remain valid for the specified duration.
Allocation of Duty
It is the pilot designated as aircraft commander for the forthcoming flight who must determine who carries out the duty. It is quite common for aircraft commanders to decide to carry out the external inspection prior to the first flight of a particular flight crew duty period themselves. It does not matter which pilot has been assigned PF duties for the departure and, provided that the person delegated to carry out the check is on duty, under the command of the designated aircraft commander, and aircraft type qualified, they do not need to be a member of the operating crew; they could be ‘heavy crew’ on long haul flights or present because of pilot line training activity.
Timing and Co-ordination
An external check should normally be conducted only after the Aircraft Technical Log is available at the aircraft and has been properly examined by the aircraft commander. However, in practice on commercial airline service, the time available before departure is tight so the crew member carrying out the external check will often commence the External Check immediately on arrival at the aircraft prior to boarding. This will require good communication on eventual arrival on the flight deck regarding any issues from the Aircraft Maintenance Log and what has been seen outside the aircraft.
Since some flight crew pre flight internal checks will also be conducted before every flight, the timing of the two sets of checks may need co-ordination to maximise the benefit of the external check and minimize any interference from internal system checks. This is especially relevant prior to the first flight of the day or before any flight which is the first for that flight crew on that particular aircraft that day, if the aircraft is boarded without an informal on-board handover from a previous flight crew.
Depending on the provision of ground services, it may be necessary to delay completing the external check until hold loading, refuelling, and other on-stand servicing activities have finished.
Personal Safety Risk
The Ramp at any busy airfield is a hazardous place, with many vehicular and machinery operations taking place in close proximity. Personal Safety when conducting an External Check on an airport ramp requires high levels of Situation Awareness on the ramp. A constant and careful lookout is essential. Attention is required in regard to slippery or hazardous surfaces, vehicles, jet efflux, aircraft aerials, masts and protruding pieces of the aircraft structure such as landing gear doors that can cause injury. Substances such as fuel, oil and hydraulic fluid not only pose a slip hazard but also may drip from the aircraft. It is important to know where to access first aid materials such as eye washes etc. in case of accident to crew or others.
Wearing a high visibility tabard or jacket is recommended, even when not mandated by the airport authority. Ambient noise levels of airport aprons can be high and the use of ear defenders should be considered, noting that these may also reduce the wearer’s situational awareness of events taking place in the vicinity. An external check will normally be conducted from ground level; any intended exception to this should be carefully assessed against the risk of falling from height and sustaining injury.