Technique: The preflight

Find the little things before they become big things

January 1, 2009

Avgas trucks never use a single-point refueling nozzle. As you sip your coffee in the pilot lounge looking through the window at your airplane, it seems like a fuel truck that has a second hose outfitted with a single-point nozzle just pulled away from your airplane.

Is it possible that they just accidentally filled your avgas-burning aircraft with Jet-A? It is unlikely, since the jet fuel over-the-wing nozzle is purposely made larger than an avgas fuel-tank opening, but it is possible.

Ah, there’s the rub. As pilot in command, you are responsible for all available information concerning that flight (Preflight action, FAR 91.103), whether it is on the ground or slipping the surleys. Preflighting an aircraft is the whole package. It isn’t just a quick run around the machine, sumping a little fuel here and there, and rocking the odd aileron and impressing your passengers with stories of your past preflight derring-do when you discovered that flat tire.

Any mistakes or oversights you make on the ground can expand into something in the air that is, at best, an epic adventure—and at worst makes your bucket list moot. That is why, whenever possible, you should watch the towing and servicing of your airplane and personally approve the addition of and the type used of any engine oil or other necessary fluids.

Going steady or blind date?

The safety difference between preflighting an aircraft you fly regularly and one you are renting or flying for the first time balance themselves out. On one hand, an airplane you are familiar with gives you the advantage of knowing every detail about how it is supposed to look. On the other hand, familiarity breeds complacency.

When preflighting an unfamiliar airplane, there is a lot you don’t know about it, but this lack of knowledge is offset by the fact that you are probably paying closer attention because you are unfamiliar.

Documents onboard

While you are in the cockpit, the most important tasks are to make sure the mags are turned off, control lock is removed, and the parking brake is set.

Sane pilots choose safety over legality every time, but what is wrong with paying attention to both? At the beginning of your walkaround, a visit to the cockpit and cabin is in order. Sure, you check for the legally required documents, but is it really that necessary? I have always thought so. The existence of current documents onboard doesn’t guarantee that your bird is safe, but their absence would make me question the whole operation.

This is a great time to grab that laminated preflight checklist you made by copying it out of your POH. It should be in your hands as you preflight your aircraft. It sounds lame to some pilots to carry a checklist, but it is a good habit. Once experienced with your aircraft, you can use it as a sort of grocery list.

Keep the aircraft’s POH handy. Do you really remember how many inches that main gear strut is supposed to be extended?

Expend a little electrical juice by turning the master switch on briefly. While the airplane is powered, take a look at the fuel quantity gauges, and you might even take this opportunity to try the lights and strobes briefly. The fuel gauge levels can be later cross-checked visually by what you see in the tanks; even if you aren’t in a position to see if the landing lights work when you cycle them, you’ll notice a huge dip on the ammeter as you flip the switch on and off.

If you need the ATIS or an IFR clearance, this might be the time to get them so you don’t waste fuel later.

Paper or silicone?

You know your passenger and fuel load. This means you have already done a weight and balance calculation. Since you have that question about what kind of fuel was boarded today, you’ll make doubly sure to check the tanks and their contents.

A lot of people use paper worksheets for the weight and balance, weather, and other flight planning chores. We live in a computer and Web-based age, and there are great flight planning tools available, such as AOPA’s Internet Flight Planner. I still like to have a paper trail of what I’ve done to get ready for a flight. If using a computer for weight and balance and weather, make printouts. At the very least, your preflight checklist should remind you to do those repetitive, but necessary chores.

Most aircraft POHs now have a note warning you about the toxic nature of aviation fuels and how it might not be a good idea to handle it with your bare hands or sniff it to ascertain its type. It is true that fuel contact and fumes have been reported to cause potential health problems somewhere in the future of those exposed. But if you have jet fuel instead of aviation fuel in your tanks, the ensuing crash will be much more harmful to your health than a polite little sniff before you aviate. Remember, there just might be enough avgas in the lines to get you into the air before the jet fuel snuffs your engine.

Stamp down high grass at airports

No matter how much fuel costs rise, it is never an excuse to not properly sump your system and tanks before you fly. Most airport ramps have a gas can handy for you to pour your sump sample into so no ecological damage occurs. The cast-off fuel is always put to good use, usually in the airport’s mowers, or in a pinch, my car.

I won’t list here what you should check as you walk around your aircraft. The items are in your hand because you are carrying a checklist. You’ll likely find the obvious and large things. Almost nobody finds a teeny-tiny item in error and saves the day. Flat tires and bent metal are the most likely problems.

Doing a proper preflight is not only a great way to stay safe and alive in the skies, it is fun if done with the right attitude. Take your time, enjoy the day, and make sure you untie the airplane as you walk around it. Not that I’ve ever forgotten and tried to taxi off with tail still securely roped to the ground.

Kevin Garrison is a freelance writer from Lexington, Kentucky, with more than 20,000 hours in 36 years of flying.