Time for Work
The flight crew arrives at the Boeing 767 freighter between 30 and 60 minutes prior to departure. If the pilots expect an on-time departure, they’ll be busy until pushback. This is a general overview of what’s involved in preparing the aircraft for flight.
Every airline develops its own preflight procedures. The following is based on my experience on the Boeing 767 freighter with one carrier. Captain, first officer, and international relief officer preflight task assignments are different at every airline. References to a certain crew member doing a particular task are examples only. This article provides a general overview of a typical preflight; some tasks have been omitted for brevity and security.
Power Up & Initialize
The first task is to make sure electric power is available. If the station doesn’t have external power (like a power cart), the crew will start the ship’s auxiliary power unit (APU) to supply electricity and bleed air. Bleed air supplies the air-conditioning packs to make the aircraft comfortable.
After power is available, a crew member turns on the three inertial reference system (IRS) switches to begin a 7-10 minute alignment process. The IRS is the heart of many aircraft navigation systems. If all other navigation sources fail (zombie apocalypse) the inertial nav system can provide guidance.
The first officer enters the current position (lat/lon coordinates) of the aircraft into the Flight Management Computer to complete IRS initialization. Crews can locate the exact aircraft position on a parking stand sign or airport chart.
The captain reviews the aircraft maintenance logbook. The logbook contains a recent history of inspections and repaired/deferred items. Typical deferred items are minor scuffs or dings on the fuselage or temporary repairs to be completed at a later date. Occasionally, a component will be inoperative. If the aircraft has sufficient redundancy, an inoperative item (like a single landing light) can be deferred for later repair.
The captain ensures an inspection of ETOPS critical components is documented before oceanic flights.
After both the captain and aircraft maintenance technician have signed the current logbook page, the aircraft is legally ready for flight. Airlines are moving toward electronic maintenance logbooks. Same idea, with digital signatures.
My airline assigns the first officer (or International Relief Officer on long flights) to inspect flight deck equipment. The inspection assures required emergency gear is on board and working.
Fire extinguishers, life rafts, emergency oxygen bottles, jumpseat oxygen masks, escape equipment, lavatory supplies, catering, and a lot more are inspected. The inspection takes a few minutes to complete.
Cockpit Setup – Go With the Flow!
Large aircraft have dozens of switches, knobs, and buttons. Pilots use checklists as a final check to make sure the important things are accomplished. A checklist that lists every item would be long and impractical. There’s a better way. It’s called a flow.
Pilots learn about each aircraft system during initial training. The next step is learning to efficiently set up the systems for each phase of flight. Every airline develops its own preflight flows. The illustrations are generic examples and do not represent any particular airline procedure.
A flow is simply a logical pattern to check each item. Pilots will often move a hand over the controls following the prescribed flow. Each crew member is assigned their own flows.
Once crews learn the flows, it takes only a few minutes to configure the aircraft for engine start. When flows are followed correctly, nothing is missed, and the use of challenge/response checklists can be minimized.
Here’s a detailed example of the first two flow movements of the overhead panel pre-flight. The crew member begins at the top left column of the panel and moves their hand over each system’s switches, checking for proper selection/indication.
The complete overhead panel flow allows the pilot to quickly configure all major aircraft systems for engine start (navigation, flight controls, engines, hydraulics, electrical, fuel, pneumatics, pressurization, etc).
Flows aren’t just for preflight. Pilots use flows for other phases of flight, like Before Takeoff, After Landing, and Shutdown. Thanks to the efficiency of flows, my airline’s 767 “Before Takeoff” checklist consists of one item: “Flaps: ___.”
Make Some Noise!
A few 767 preflight checks make a little noise. Crews typically test the TCAS and Radar/Windshear systems before the first flight of the day. They’re included in the center console flows pictured above.
A small button on the transponder control panel activates the Traffic Alert and Collision Avoidance System (TCAS) test function. The test displays various TCAS symbols on the flight displays, as well as an audible voice test.
Selecting the test mode on the radar control panel initiates the Radar and Windshear System test. This is our “noisiest” preflight test. The test in the video is on a newer aircraft with predictive windshear (uses doppler technology); it’s a little different than the test on older aircraft.
Exterior Walk-Around Inspection
After finishing cockpit setup flows, it’s time for a crew member to grab a flashlight and walk around the aircraft. The captain performs the walk-around at my airline (first officer at many other carriers). The exterior inspection is my favorite part of preflight. I really enjoy the walk-around and never delegate in bad weather… typhoon, snow, sunshine, I don’t care. I enjoy the walk to see what I can find.
Not surprisingly, the exterior walk-around is really just a giant flow. Pilots learn the items to inspect, then follow the flow diagram so nothing is missed. It takes five to ten minutes to complete a walk-around.
What are we looking for?
An aircraft maintenance technician gives the aircraft a detailed arrival and pre-departure inspection. The pilot’s job is to give the exterior a final look to double check the general condition of the aircraft, along with a few specific items.
Stuff we look for: Loose/missing inspection panels, unlatched maintenance access doors, pitot covers and gear pins, condition of probes, pressurization valves, tires, evidence of leaks, foreign object damage, and snow/frost/ice. There’s a lot to check, but it’s easy when you go with the flow.
Programming “The Box”
While the captain is strolling around the aircraft, the first officer programs the flight management computer (FMC), often referred to as “The Box.”
The crew programs the box with aircraft coordinates, weight, route of flight, winds aloft, and performance requirements (speeds and altitudes) as planned by the dispatcher.
Depending on aircraft, airline, and type of FMC, the crew may be able to download the information via datalink. A pilot with exemplary typing skills can complete the task manually in about 10 minutes. When complete, the other pilot proofreads the programming.
Takeoff Performance Data
Shortly before loading is complete, a load supervisor provides the weight and balance data to the crew via paper, or ACARS datalink. A pilot loads the data into the FMC and submits an ACARS takeoff performance data request for the expected runway (in the old days, we used thick binders of airport specific charts).
ACARS: Text messages for flight crews
Aircraft Communications Addressing and Reporting System (ACARS) is a digital datalink system for transmitting messages and data between aircraft and ground stations. It’s been around since 1978.
My airline uses Garmin subsidiary AeroData to deliver live takeoff performance data to the aircraft. AeroData provides the crew with runway-specific takeoff thrust setting, speeds, flap setting, and critical engine out performance data. It takes only seconds to submit a request and receive the response through ACARS. The performance data takes into account current weather, weight & balance, and configuration options specified by maintenance, dispatch, and/or crew.
The above image displays an example of live data received via ACARS for departing Kuala Lumpur runway 32R from intersection A9. The takeoff performance report provides a tremendous amount of information. I print the report with the aircraft’s thermal printer for easy reference.
After the crew completes the preflight flows, the captain calls for the preflight checklist. Thanks to flows, the checklist is short and sweet. A typical 767 preflight checklist has about 5 items. Here’s an example:
- Cockpit Windows – Closed and locked (pretty important!)
- Oxygen system & masks – Checked
- Altimeters – ____
- Parking Brake – Set
- Fuel Control Switches – Cut Off
We’re almost ready to start the engines.
About ten minutes before departure, the flight crew requests a route clearance by VHF voice or data link. The clearance delivery controller (usually located in the control tower) will tell the crew their expected runway, departure route, altitude, departure frequency, and a transponder code. A typical departure clearance from Kuala Lumpur:
Aerosavvy 101, cleared to the Shenzhen airport via runway 32 right, KIMAT One Delta departure. 5000 feet. Lumpur Departure 135.25. Squawk 2137.
After scribbling down the clearance, the pilot will read it back to the controller for confirmation.
Loading is nearly complete and the crew is running out of things to do. The captain and first officer will determine whose turn it is to fly (captain’s decision, coin toss, or rock/paper/scissors). The flying pilot will brief the departure:
OK, Skipper [I always laugh when they call me “Skipper”], we’re departing KL runway 32 Right. Taxi route will probably be Hotel, hold short of Bravo. Let’s be careful after Bravo, taxiways are confusing; likely Bravo 13 and Alpha 11 to the holding point.
Takeoff will be NADP-2 on the KIMAT One Delta SID. I’ll call for autopilot at 200 feet. LNAV is already armed. VNAV at 1,000 feet. We’re cleared to 5,000. Transition altitude is 11,000.
If we have an engine failure after V1, I’ll fly straight ahead to 1,100 feet. After that, our engine-out procedure is to continue runway heading. Let’s climb to 4,000 and plan on returning to 32 Left. We have 3,000 pounds in the center tank we can dump if we need to.
Threats tonight include a few thunderstorms near the coast. We may need to deviate a little north. It’s our first night flight this schedule, so I plan on making coffee when we reach cruise. There’s hot water in the pot.
I’ll select terrain, you’re on radar. Any questions? No? Groovy!
And that’s it! When the ground crew finishes loading, the pilots will close the doors and buckle in. The aircraft is ready for pushback and engine start.