From the One-More-Time-But-With-Pictures file comes this week’s Best of the Web video. It was posted by Cessna Centurion owner Edward Frye earlier this week. It depicts a successful runway turnback after a catastrophic engine failure. Total time in the air: one minute, 12 seconds. Frye does a nice job of analyzing the incident, including illuminating his own oversights, with views from inside the cockpit and out. We should all do so well in handling a similar emergency.
As I’ve observed before, I’m agnostic on the turnback maneuver. Sometimes it’s a good choice and sometimes not. As the video shows, Frye’s decision worked and he even managed a Scott Crossfield-style taxi off the runway, sans the hangar wall. The incident occurred at Tracy Municipal Airport in California, which is located in a relatively flat area near Stockton. He departed Runway 30 and after the engine failure returned to Runway 8, a turn of about 220 degrees and near ideal geometry for a turnback attempt.
There’s a dense commercial industrial area off the end of 30 and to the west of that, a large open field that might have also been reachable. I wouldn’t second-guess the decision because I wasn’t in the seat and why argue with success? Frye explains the circumstances that led to his predicament. The 210’s engine had just been overhauled but not operated on a test stand. Having read articles about cylinder glazing, Frye found recommendations to run the engine as little as possible before setting full power to seat the piston rings without tanking the cylinder walls. He said it had only been run for a few minutes and he rushed to the runway to get airborne against a setting sun for a few minutes of high-power flight time.
Personally, I’m not a fan of initial break-in by flying an engine. All of the half-dozen overhauls I’ve dealt with have been properly run on a test stand and the resultant data recorded in the engine paperwork. And even at that, on the first flight, I did high-power runups on the ground and returned to the ramp for uncowling and inspection before flight. I did that when we overhauled the Cub engine, which had been run on the stand, albeit a rudimentary one. After an annual, I perform a similar inspection and I conduct at least one high-speed taxi test.
This comes not from personal calamitous experience but from reading scores of accident reports following maintenance and overhauls. Failure of a freshly overhauled engine is not an everyday thing, but it’s not rare, either. The very scenario described in the video happened to a friend of mine, but before takeoff during a high-power runup. I’d rather have it blow up on the test stand or on the ground rather than after takeoff. In Frye’s engine, a rod came unglued and blew a hole in the crankcase, suggesting the undertorquing that is a common failure scenario.
The advice to run high power for initial break-in is accepted wisdom, but having never seen any data on the incidence of cylinder glazing, I wonder if the risk of that is worth the risk of rushing through a runup or even towing the airplane to the runway and starting it for immediate takeoff. I’ve seen that done, too. As Frye points out, rushing through all of this led him to forget his shoulder harness, something I suspect we’ve all done.
If I had anything to add about Frye’s technique, it would be to hold the landing gear. He extends it pretty quickly after the failure and although he makes it to Runway 8—3438 feet long—he doesn’t have much altitude in the bag. Better to save the drag until the bitter end when you’ve got the runway made (and then some) rather than deploy too soon and land short because of it. That sort of defeat snatched from the jaws of victory is an occasional accident narrative, too.
As for turnback versus no turnback, the debate will rage on, I’m sure. Frye’s video is a brilliant example of how it can work, without suggesting that it always will.