Sunday, July 15, 2007

John Mohr: Energy Management in a Gorgeous Boeing Stearman PT-17

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As many of you know, I spent a long weekend at the Battle Creek Balloon Festival and Field of Flight Air Show in Battle Creek, Michigan this year.

Barb and everyone else there did a great job of selecting a really good range of performers. There was something there for everyone. I really liked every performance that I saw. There were absolutely no flies on any of the performers and everyone demonstrated the very best of what his aircraft offered. But one performer in particular made me stop and really watch closely.

Out there at air show center was a blue and gold Boeing Stearman PT-17 doing really amazing stuff.

I don’t think that most of the audience really understood what it was watching. I can’t blame anyone for being the most thrilled about the jet teams, but I realized that what I was watching was probably the best stick and rudder work of the whole air show.

The PT-17 probably has the lowest thrust-to-weight ratio of any of the aircraft in the show. It has a big Continental R670-series engine, but it’s a 1943 vintage engine that doesn’t put out a lot of horsepower and it’s hauling a really big airframe around.

It has an exclusively gravity-fed fuel system with no boost pump and, when goes inverted for too long, the engine burns whatever fuel is in the lines and then quits. The pilot then has to get right side up and stay that way until either the gravity feed system gets fuel back to the windmilling engine or he can land.

Except for the final sequence, the PT-17 did the entire show below 500 feet AGL and that included a lot at 200 AGL or lower.

For my money, it was the best demonstration of energy management I’ve ever seen. And that’s kind of cool for those of us who fly more average general aviation aircraft. I really enjoy seeing Brett Hunter and Michael Mancuso and Mike Goulian tear up the sly and those guys are cutting-edge pilots in anybody’s book. But a big part of my appreciation for their particular demonstrations has to do with the raw power of their respective aircraft.

The chances are excellent that I’ll never fly an airplane that hot. But the chances are as good as my flight in a Cessna 172 on Tuesday that I’ll fly an aircraft with a much less dramatic thrust-to-weight ratio that that will require skill and balance much further down the thrust-to-weight curve. I was in awe at how far ahead of the airplane the PT-17 pilot was and saw a great demonstration of excursions into parts of the flight envelope that are a lot more akin to what I experience.

I guess I’m saying that the Blue Angels, Mancuso, Goulian, and others fed my soul that day, but the PT-17 and its pilot taught me some things. I came away a little ashamed at how much I hate the mushy feeling of slow flight and being behind the power curve, even though I’m in an airplane of very modern design and have thousands of feet under me whenever I do it. The truth of the matter is that’s where the best of the best really shine and it’s one of the proudest maneuvers of a true stick-and-rudder pilot.

Late Sunday afternoon while waiting for a balloon slot, I hitched a ride to the ramp at Duncan with the WGVU team I met last year in the hopes of snagging an interview or two. And what should be on the ramp but that gorgeous PT-17.

I was lucky enough to meet and interview the pilot of that PT-17, John Mohr of Mohr Barnstorming.

The audio here is a little noisy. The winds were pretty high out on the field and they were tearing down the ramp at Duncan Aviation at five to 20 knots. The MicroTrack 24/96 is a great little machine, but it’s tough to gyrate around and keep it shielded from the wind. Sure, we could have done the interview in the hangar, but means ten fewer minutes standing next to a really beautiful aircraft and, given that choice, you know what I’ll choose every single time.


I need to interject from the studio here. John’s a real pro and I could have run the interview as recorded without editing, but I want you guys to hear this. Here’s a part of his performance from the previous day where he stays inverted long enough that the engine quits from fuel starvation.


Okay, back to the ramp.


John will be at Oshkosh July 23 through 29 and then he performs August 11-12 at the Bay City Air Show at Bay City, Michigan, August 18-19 at the Canada Remembers Air Show at Saskatoon, Saskatchewan and then August 25-26 at the Wichita Flight Festival at Withica, Kansas. After that, it’s on to Toronto, Terre Haute, Columbus, St. Petersburg, Randolph AFB, and Stuart, Florida. See more schedule information at

Thanks to John for taking some time to talk to us at Airspeed and thanks also to the Battle Creek Balloon Festival and Field of Flight Air Show.

Another reminder that Pod-a-Palooza is scheduled to take place at Oshkosh on Friday, July 27 at 5:30 in Forum No. 2. Time and place is subject to change up to – and even during – the event, so please be sure to check the schedules when you arrive. It’s organized by the guys at The Pilotcast. Scheduled to appear are Pilot Mike, Pilot Dan, and Pilot Kent of The Pilotcast, Jack Hodgson, Dave Higdon, and Jeb Burnside of Uncontrolled Airspace, Jason Miller of The Finer Points and The CFIcast, Private Pilot/Student Pilot Will of The Student Pilot Flight PodLog, and, of course, yours truly, Stephen Force.

Join us! It’s a chance to actually meet the voices in your head!

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