Twin-Engine Temptation
July 2010
You want a twin-engine airplane. You know you do. If you've ever flown at night in the clouds, or over long stretches of water, or had a vacuum pump quit or heard the engine burp, you've at least thought about trading your ol' reliable single in for one with two engines. Maybe your thinking is less fear-based and you want a twin for more performance or ice protection or load-carrying capability. Maybe you just want a fistful of throttles, props and mixture controls. Everyone thinks a twin-engine airplane is safer because it has a lot of redundancy and a "spare engine" in case one quits.
Avemco® insures a lot of twins, and an analysis of NTSB data show that their fatal accident rate is four times that of single-engine airplanes*. So flying a twin doesn't necessarily make you safer. In fact it seems to increase the risk unless you put into it what's needed to stay current in twin-engine airplanes.
Can you handle it?
With two of everything to control and monitor, you have a higher workload in a twin. Can you handle it? Flying with two engines means you need to be on top of your cockpit-management game. If you ever feel behind the airplane now, you'll need a lot more practice to handle a twin. And that's with everything working.
What if one quits?
Ah, here's the issue. In a single-engine airplane if the engine quits the airplane will nose down (unless you panic and try to hold altitude, then you'll stall). The wings'll stay level and the airplane tries to fly straight ahead (toward the ground, of course). If you're surprised or a little off your game that day or near the ground you'll have only a moment to get your wits about you.
In a twin-engine airplane, if an engine dies the other engine will try to roll the airplane over on its back and point its nose toward the ground. To avoid imitating a lawn dart you need to immediately apply hard correct rudder against the yaw, push or pull to the right pitch and roll in the right amount of aileron to keep the airplane flying. Then, you've got to figure out which one died and get its prop feathered. All this happens while you're still on that instrument departure or making a frequency change en route or briefing yourself for an approach. You don't have time to be surprised, and you can't afford to be a little tired or having a bad day when this happens!
And, since you have two engines, theoretically you're twice as likely to have an engine failure in a twin-engine airplane!
So how is this safer?
Safety in a twin-engine airplane comes not from the extra engine itself, but your ability to immediately fly correctly on a single engine, with no notice, at any given moment. The only way you can do this is to practice. You wonder why Avemco (and everyone else) requires so much pilot experience before we'll insure you in a twin? Why we need you to get so much instruction in the specific type of twin at the beginning of your policy? And why we may ask you to get additional training every year for your policy to be renewed? This is it. You are a primary safety feature in multiengine airplanes.
So if you're considering a twin-engine airplane, or have one already, schedule some regular dual instruction in an appropriate simulator or with an MEI who's expert in your type of airplane as part of the price of multiengine safety.
*NTSB data analysis provided by Thomas P. Turner of Mastery Flight Training, Inc. (www.mastery-flight-training.com).
Avemco® does not provide technical or legal advice. Content contained herein is for general information and discussion only, and is not a full analysis of the matters presented. The information provided may not be applicable in all situations, and readers should always seek specific advice from the FAA and/or appropriate technical and legal experts before taking any action with respect to matters discussed herein.
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