Ian Twombly

Risk management

November 11, 2008 by Ian J. Twombly, Associate Editor

Acting as pilot in command has many responsibilities, not the least of which is getting to the destination safely. But meeting that goal can happen any number of ways.

In the November issue of Pilot I made reference to the fact that I flew over Lake Michigan on my way to Oshkosh in the sweepstakes Archer. Recently I received an e-mail from a member who felt what I did was foolhardy, displayed poor judgment, and was a “stunt.” The message got me thinking about what the risk really was and whether I had put myself and my passenger at risk and not properly exercised my position as PIC.

During the flight, I figured I was beyond gliding distance from shore for 10 miles. The Archer had less than 100 hours on a newly overhauled engine, it was summer VMC, and I had plenty of fuel. David Kenny, the statistician for ASF, ran some numbers and found that there were roughly 500 accidents and incidents last year in which the airplane quit producing thrust for one reason or another. Only 250 of those were evenly remotely attributed to mechanical error beyond the pilot’s control, and that is probably a stretch.

According to Kenny, the latest FAA survey of GA flight activity found a total of 24.4 million hours flown last year. Factor in the engine failures with the time I was beyond gliding distance from shore, and the chances that the engine would have quit in those 10 miles works out to something like one in 400,000 to one in 750,000.

To put that number in perspective, the chances of being struck by lightning have been reported as one in 600,000. The odds of dying on your bicycle? One in 4,919. The odds of dating a supermodel? One in 88,000 (don’t ask how they came up with this one). The point is, it’s highly unlikely the engine would have failed during that 10 mile gap. But the idea of it happening is so scary, so unnerving, that it caused someone to write in and say I was crazy.

The broader question is obviously how much does real risk equal perceived risk? To me, flying over Lake Michigan felt more comfortable than flying through rural Pennsylvania in the winter. Others would never fly to the Bahamas, the Keys, Catalina Island, and other wonderful places if they couldn’t fly beyond gliding distance from shore in a single.

But this is only one judgment call. We make hundreds a year in airplanes that other pilots may find suspect. I’ve heard of airline pilots who won’t fly a single engine airplane at night. Other pilots maybe wouldn’t fly if it’s 3,000 overcast. It seems as though personal minimums are only the beginning of the story.

So was I crazy? What is smart in an airplane and why? Do the stats justify the perceived risk? In many cases, I don’t think so.


3 Responses to “Risk management”

  1. Drew Says:

    I think another question to ask is what was your risk of serious injury or death should you have had to ditch in the water. A quick mayday on the radio combined with a good chance of activating that new ELT would result in a coast guard vessel or chopper within 30 minutes or so. I’m guessing you didn’t have a PFD so I’m assuming you felt comfortable enough to be treading water for awhile. Although a water landing can be very unpredictable (even a slight wave could send the aircraft cartwheeling), it isn’t any worse than being forced to land on some semi-rugged terrain that we all fly over every day. The probability of getting away with less-than-major injuries was quite good and certainly amounts to a reasonable amount of risk given aircraft reliability.

  2. Donald Blust Says:

    I really appreciate the quantitative approach to assessing risk. My private pilot flight training took place at Timmerman field in Milwaukee. Subsequent to becoming a certificated pilot I had ample opportunity to fly over our great lake but always elected not to. With contemporary PLBs, ELTs and proper use of the radio one would think a rescue would occur pretty quickly. Members of my flight club have often discussed their flights throughout the Florida keys…and I have always thought they were pretty daring. Suddenly I feel differently about it all. As I said I like the statistical probability approach. I pride myself on my preparedness and that of my aircraft. I can only imagine the awe-inspiring sensation of being PIC of a single over a large body of water. And I bet making the “go / no go” decision at altitude 20 miles from the departure shore would be a pretty damn exciting moment!

  3. JimSandison Says:

    I drive around the Wash. DC belt way every day. The risk of being run over by an 18 wheeler is not unlike flying over lake michigan. Think I would rather be “one and done” in Lake Michigan than all over the beltway.
    Jim S.

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