Start your engines
It’s trickier than expected
Modern cars have spoiled us.
Start me up
There are many ways to start a piston engine. Here are three distinct methods.
Older airplanes without electrical systems require the pilot to throw the propeller through its arc until the engine takes over. It’s perfectly safe with training.
Carbureted engines will need a few pumps of the primer in the winter, possibly none in the summer, and some cranking until it fires. Don’t hold that starter for longer than a few seconds or it will burn out.
With their electronic ignition systems, Rotax engines tend to start as reliably as a car, regardless of the weather or if the engine is hot or cold. They also stop like a car, by flipping the ignition switch.
Unless you have a dead battery, turning the key or pushing the button in your car reliably brings the machine to life, whether gas, diesel, electric, or hybrid. Hot, cold, and anything in between, we have come to expect perfection from our cars. If only airplanes were so easy.
Starting a piston-engine airplane is closer to starting a 1930s tractor than it is a modern car, and starting a jet or helicopter takes such specialized training you may as well be operating a…well, power plant. Why the process is so antiquated and takes a certain level of voodoo is due more to the costs of certification and the expectation of redundancy than to a lack of technology. Magnetos—those spinning magnets that provide the electrical jolt to the spark plugs—are indeed early twentieth-century technology. Because they operate independently of the electrical system, an electrical failure doesn’t result in a power failure. But it does make life harder for the pilot.
Many small aircraft are also carbureted, which adds its own layer of challenge. To get a reliable start, begin with the manual. Most will advocate for using the primer, and if that doesn’t make starting easy, have the mechanic take a look. Many primers on older airplanes have become clogged or otherwise no longer function, so instead of pushing fuel to the engine you may just be pushing air.
Pumping the throttle is another time-honored technique, but not necessarily a good one. This puts the fuel in the wrong place and can cause a fire. And don’t even get us started on fuel injection. It can enable easier starts, but only when cold. Starting while hot is a black magic that is unique to each airplane. Many small airplanes have different cockpit controls as well. A key that includes positions for Off, Left, and Right mag, and then a spring-back position to operate the starter is traditional. You’ll also find some keys that must be pushed in to start, a few airplanes with push buttons, and some with toggle switches.
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