Posts Tagged ‘hydraulic pressure’

The many ways of doing the same things

Monday, March 26th, 2012

Pilots are odd creatures. We all learn the same basic fundamentals of flying, and we all learn the same set of FARs. We also learn in the same basic set of airplanes: single-engine Cessnas, Pipers, and more recently, Diamonds and Cirruses. But fly with two pilots from a specific group, and the odds are that they will do a lot of things differently. Some may use the checklist diligently, some not at all. Some will always use flaps on takeoff, some won’t. They may use different speeds in the pattern. Yet, we all manage to take off and land safely most of the time.

The airlines and corporate departments counter this by coming up with a rigid set of protocols that allow two pilots who have never even met before to know exactly what to expect from each other when flying together for the first time. The system really is quite extraordinary.

What is truly amazing, though, is to watch two airlines operate a similar airplane in such wildly different fashions. I’ve flown on the jumpseat of the 737 for more than one airline, and while I didn’t pick up on all the subtleties and nuances, I definitely could see some differences. I really notice it when sitting on the jumpseat of another airline’s CRJ, which is what I fly.

Single engine taxi is a common strategy airlines use to save fuel. My company only does single engine taxi on the right engine because the right engine will provide enough hydraulic pressure to all the brakes without a configuration change. Others will alternate engines, and simply use the hydraulic pumps to pressurize the brakes. Neither is more right or wrong than the other. Our system eliminates a potential human error, and the other ensures even run time on the engines, which saves money.

Checklist philosophy is a major difference. My company requires that every checklist be verbalized by at least one crewmember, if not both. That way, in the event of an accident, the CVR will confirm whether the checklist was completed. Other carriers only verbalize certain checklists that are designated as “challenge and response.” There are pros and cons to both methods.

Sometimes, you see items on a checklist that make you say, “Really? Why is that on there?” Somewhere in the management structure is a person or persons whose background provides a reason. Or maybe they just don’t like the way something looks on a screen, so they create a checklist item to clear it. It happens.

More carriers are coming up with ways to deal with cell phones being left on. I never thought I’d see the day. The truth is that we should probably all have that. More than once mine has started vibrating on takeoff or landing…even at 10,000 feet. Oops.
Carriers will also use different flap extension speeds based on their own experience with flap issues that may be related to aerodynamic pressures caused by high speeds. Sometimes crews are mandated by their carrier to have the gear down at a certain point. We even use different maneuvering airspeeds. A carrier that has a lot of low time, new-hire pilots or a lot of turnover will build in more conservatism than a more stable or experienced company.

The biggest problem with checklists is complacency, and the best way to deal with that—in my opinion—is to change them just a little bit every six months or so in an effort to prevent relying them on memory alone. Just don’t count on anybody else using the checklist in the same way.—By Chip Wright