It was with great anticipation that I fired up N75YR this morning. The mission: Fly the airplane to the Sun N’ Fun Fly-In, where it is now on display at the AOPA booth. But first things first. I desperately wanted to know how the Debonair would perform on its first cross-country flight. Today would be the first real-world flight for the overhauled/converted IO-470-N.
Let me end the suspense right now by saying that there were no disappointments! Engine start for the 37-degree, 7:30 a.m. departure was uneventful, and the start procedure was identical to the one I’d learned worked best on the predecessor engine. The trick is to use less throttle during the priming for a cold start. So the best drill here is to go mixture full rich, then use slightly less than half-throttle while you hit the auxiliary boost pump (it only has a “high” pump speed switch position) for maybe four seconds. Then pull back the throttle so that it’s in the barely-cracked position. Now move the magneto switch to Start and the engine will respond every time. That’s the cold start drill.
Those of you with time in big-bore Continentals like the 285-hp IO-520, or the 300-hp IO-550 can get into trouble starting the Debonair if you prime like mad using full throttle. The Deb will flood if you do that. Trust me, I know.
Preflight checks done, I line up on home-base Frederick, Maryland’s (KFDK) runway 30 for the takeoff, then firewall it. I’m right at gross, with all tanks full for the 728-nm trip to Sun N’ Fun’s Lakeland Airport (KLAL). The airplane lifted off into a slight crosswind, and soon I was climbing out at 100 KIAS and 900 fpm. Not bad at all.
Turbulence was forecast, and the forecast was correct. The climb to 6,500 feet was bumpy, and any rolling motions were exaggerated by all that fuel out there on the wingtips–20 gallons, or 120 pounds, per side.
John Clegg, director of operations at Genesis Engines by D’Shannon told me to “run it like I stole it,” meaning run it at high power, to help seat the ECi cylinders’ rings properly. So I did. Level at 6,500 in severe-clear conditions, I firewalled the throttle, set the propeller for 2,580 rpm, and used the Electronics International MVP-50P engine/systems analyzer to lean 50 degrees rich of peak EGT.
When things settled down, the Aspen PFD told the tale. At 76 percent power I was doing 170 KTAS while burning 17.3 gph. That’s a Bonanza-style cruise speed, friends. But the Bonanza would get that speed using a 300-hp engine. This Deb does it on 260-hp.
Airspeed fluctuated in wave activity as the S-TEC System Fifty autopilot worked to keep the altitude steady. Pitch angles varied as the nose rose and fell trying to compensate for the up- and downdrafts.
As the airplane burned fuel, its weight went down and by the second hour of flight I was looking at 178 KTAS, but burning 18.5 gph to get 78-percent power, in keeping with the “stolen airplane” performance profile. Nice.
And did I mention that I had a tailwind? Oh, yes, 35, and sometimes 50 knots’ worth. My groundspeed hit a high of 215 knots at times, then settled down to a more modest 183 knots by the time I reached Florida.
Oh, and did I mention that my flight path was straight as an arrow?
Bottom line: four hours, 12 minutes after takeoff, I landed at Lakeland. Non-stop, of course.
A great flying day in a great airplane, I’d say!
Stand by for more Debonair news during the show. It will be interesting to see how visitors to the tent react to the engine upgrade. Maybe you’ll stop by? Hope so.