Van's RV-9A in Aurora

The Big Picture

The Big Picture
Flying! 8/28/2011

Monday, October 17, 2011

Phase 2

I took advantage of nice weather this weekend and finished flying the 40 hours of Phase 1 flight testing. That included redoing climb performance data at a lighter weight with the wheel fairings installed. This allowed me to establish the Vx and Vy speeds for the new configuration. I also repeated stall testing. Then I loaded the passenger seat back up and flew again, doing stability checks, more climb data and descent data.
I also ran climb to altitude tests over several flights to measure fuel consumption, time to climb, and distance from departure point for +3000, +6000, and +9000 foot departures. The climb to 4000 feet only burns .8 gallons, and that includes starting the engine, taxiing, runup, takeoff, and the climb (starting from 900ft). The climb to 10000 took only 2.8 gallons, and got the plane 27 nautical miles toward the destination.

Somewhere in all that testing I landed at Fredricksburg and had lunch at the airport diner.

The final flight of the 40 hours was a trip to KAUS (Bergstrom) with 200 lbs in the right seat, and 80 1bs in the baggage compartment. I wanted to check the operation of the localizer and glide slope information on the ILS approach to 17L. Unfortunately it didn't work. I guess I should rule out the ILS being out of service before I declare my equipment not working.

All this weight was in the airplane!

So with 40 hours, Vx, Vy, and Vso (stall speed with full flaps) and all the important testing and data collection done, I made the aircraft log book entry to officially end Phase 1. So my operating limitations are relaxed. I can now take a passenger, fly at night, fly over populated areas and in congested airways during cruise (which I'll tend to avoid anyway), and file an instrument flight plan.

Another interesting thing happened. I had been burning about a quart every 6 hours. When doing climb testing, it was much more, like 1 quart every 2 hours, which might mean it was going out the breather tube. With the wheel fairing on, I can fly about 10 knots faster, which allows the prop to finally turn at full RPM. In fact I can now redline the engine at 2700, which I couldn't do without the wheel fairings. With the faster cruise and high RPM/manifold pressure, I am able to really push the engine hard in cruise. So after about an hour of that, the oil consumption has dropped so that I've probably only burned 1/8 quart in the last 3 hours. Which hopefully means that the rings are seated and the engine is broken in. We'll see how the next 10 hours go.

And finally, on the same day, I went over 300 hours and 500 landings, and my repairmans certificate came in the mail. What a weekend!