Since I will be heading out of town for a few weeks sans airplane, I took the opportunity this morning to do one more flight this morning.
The weather is fantastic. Not a cloud in the sky or a whiff of a breeze on the ground. This time of year is really stellar here: about 40 degrees F on the ground and altimeter at 30.54, so does not get much fairer than that! Density altitude for takeoff was well below field elevation �of 4750 MSL at around 4000’ DA and no turbulence at all altitudes.�
I decided to fly south to a nearby airport, make a few circles around it and return home, so just about 1 hour of flying total. I am celebrating: 3+3 (3 years and 3 days) since my first flight in my Q! Once I got it up and stabilized for cruise at 6200’ MSL, I decided to set the throttle to economy cruise and just leave it there for the whole flight. So I did not touch it for the out-and-back. I had it leaned to best power and was reading close to 5.9 gph for the duration of the flight.
I engaged the autopilot to remove the human factors and started taking in the scenery and watching the numbers.� Since the OAT was around 38 F, I decided to completely close my radiator doors to do a controlled test of how much that changed my cruise speed with constant power settings. I was happy to find that it went from 150 mph TAS to 160 TAS with the air doors going from 1/2 closed to fully closed (there is still about �” gap when fully closed, so the radiators are still “breathing”). My coolant temp went up but stayed in the green at about 180F, and my oil temp was about the same at 185 F. Also, closing the radiator doors increases the pressure and air temp behind the radiators, so cabin heat air temp and flow goes up and makes for a very comfortable cabin. �So, it’s a win-win all around. We all know that cool air is a pilot’s friend, but I keep finding that is especially true for my airplane.
The airspeed test also reinforces what Sam H. preaches. Namely, that these are very slick little airplanes and whatever you can do to reduce any drag points will make them even slicker.
I was sorry to put it back in the hangar for the next few weeks, but I was happy to have an enjoyable hour in the western Colorado sky. Anyone who is still building, keep at it and get it in the air!
Jay Scheevel� Tri-Q2 N8WQ, �197 hours