Kochman Family RV-10 Rotating Header Image

Testing

Flying again!

After almost 5 weeks, I’m back in the air.  Did a quick post-maintenance flight on Friday evening, and everything is working well.

Tulips

I’m a little late in posting this, but I did much of the test flying between the Arlington and Skagit airports, during the height of the Tulip Festival.  I didn’t get great pictures (was generally too high), but here’s a view I often got from a few thousand feet.

Sandbaggin’

As I mentioned previously, part of flight testing is flying at different weights and centers of gravity.  I used sand, which was cheap, easy to get, and pre-measured in 50 or 60 lb. bags.  It can be messy, though, so if I was going to do more extensive testing or test multiple airplanes, I think I’d find a better solution.  It worked well enough, though.

Here’s a picture of a few bags strapped into the rear seats.

Phase 1 Complete!

“Phase 1” is the testing phase.  For a certain number of hours (40 in our case) after certification, the airplane is restricted: can go only 50 nm from the home airport, no passengers, daytime only, VFR only, and no flying over congested areas.  You also have to test the airplane to ensure it has no dangerous handling characteristics (at different weights and center of gravity positions) and to also figure out how it performs (e.g. best climb  and descent speeds).  Well, I’m done with that now.  No more flying sand bags.  Time for Kelly to get a ride.

Quick Update

It’s been a really wet spring, so haven’t done as much flying as I’d like (have I complained about that before?).  The weather is starting to get better, though.  Sunset is after 8 p.m. now, so plenty of time to fly after work these days.  I’m up to about 14 hours now.

The other day, an V-22 Osprey did a touch-and-go at Paine while I was waiting to take off.

My sister, Catherine, and her boyfriend, Colin, were in town last weekend, so we had to check out the plane.  They look happy here, but Catherine said she’d need a bunch Xanax to be able to fly in it.

More Fixes and More Bad Weather

It’s been almost two weeks since the last flight.  The last one was a good one, though, flying over Arlington for a while, then heading up to Skagit and back.  I’m slowly getting more comfortable venturing away from the home base and flying outside gliding distance of an airport.

No flying since then, though, mostly due to weather.  I’m working on fitting the gear fairings–the wheel pants are done, so next flight will be with those, but I still need to do the upper intersection ones, so no leg fairings for now.

I was also able to fix the electric fuel pump, by replacing an o-ring that was sticking.  Now the pressure doesn’t shoot up to ~80 PSI every time I turn it on.

Lastly, I’m still getting erratic RPM readings above about 2650.  I’ve increased the resistance in the line between the p-lead and the Dynon from 76 to about 100 Kohm, so hopefully that’ll fix it.

 

Two Week Update

It’s now been two weeks since our first flight.  We now have 8 flights and 5.3 hours on the airplane.  The temperatures and oil consumption have stabilized, so I think the engine is pretty much broken in.  The erratic RPM reading is still there–it’s better since I increased the resistance in the sensor line, but I need to add more.  Still have the heavy right wing, so am really going to have to try hard to resolve it.  Everything seems straight, so I’m wondering if the left aileron underside is slightly concave (which I’ve heard has happened to people).

On Saturday, I did a short flight in the morning (after trying, but failing, to calibrate the left fuel tank sensor).  I went back in the afternoon and successfully calibrated the right tank sensor and went for the longest flight yet: 1.5 hours.  On Sunday, I flew to Arlington to drop off some scales for John Marzulli (CH 701), which was my first landing at an airport other than Paine Field.  By the time I left, it was really windy and I was hungry, so I just went back to Paine.  Winds were gusting to 22 knots and I made my first landing on the small runway (34R), so that was fun.

The weather looks like it’ll be decent a couple days this week, so hoping to get some flights in after work.

Here are a couple pictures.  At Paine on Sunday morning, I took off behind a 747-8F.

Since Boeing is still working on certifying the 787 and 747-8 series, they can’t deliver these airplanes, but they’re still making them, so they’re running out of space to park them.  They’re so desperate for room, they worked out a plan with the county to park them on the crosswind runway (11/29) through at least the rest of this year.  Here’s the first one, parked just beyond the end of our hangar building.

Onboard Camera

Thanks to Chad Hankins (RV-7) for letting me borrow his GoPro Hero HD camera.  I mounted it to the door strut attachment bolt on the right door, which worked okay.  Here’s a video of the takeoff and landing.  The video quality on the landing isn’t as good, since it was getting dark by the time I landed.

Second and Third flights

There were a few things that needed fixing after the first flight:

  • Idle mixture was still to rich
  • One of the oil cooler fittings was leaking a little (I really dislike tapered pipe fittings on airplanes)
  • Prop governor needed to be adjusted to give 2700 RPM maximum (was getting only about 2600)

With the help of our friend Marc, we addressed these things and cowled it up for another flight on Sunday.  Same plan as before, circling the airport at 3000′, but did a full 30 minutes in the air this time.  After landing, we took the top cowl off again to check for problems.  The oil cooler leak is gone, but there are still a couple areas losing some oil: at the oil sump and one of the oil return lines.  These things are annoying and messy, but not a safety issue.

After work on Monday, I went back out to the airport to get another flight in, since the weather is supposed to be crappy for the rest of the week.  Same as the last flight, pretty much.  This time I took a picture and a quick video with my phone.

Other things that need to be fixed, but not urgently:

  • The right wing does seem to be slightly heavy with the flaps up, so will take a look at how to fix that
  • The manifold pressure gauge fluctuates within about 1″ or so.  This is a common issue and is fixed by putting a restriction in the line
  • Idle mixture is getting better but is still a little too rich
  • Need to figure out some good starting autopilot servo settings for the RV-10.  I’ll have to tweak it in flight, though.

First Flight!

After three years, six months, and one week, our RV-10 finally had its first flight on Saturday!  Rob took off from runway 34L at Paine Field, climbed to 3000 feet, circled the airport for 15 minutes, then landed uneventfully.  Despite some nerves, the flight was a success.  Only 39.75 more hours to go until the test period is complete and Kelly can ride, too!

Our RV-10 is powered by an Aero Sport Power IO-540-D4A5 (260 hp), Silver Hawk EX FI system, with a slick mag on bottom and Light Speed Plasma III on top.  The instrument panel has a Dynon D100 EFIS, Dynon D120 EMS, Garmin GNS 430 GPS, and panel-mounted Garmin GPSMAP 696.  Interior by Flightline Interiors.  Our tail number is 819K: 8/19 is our wedding anniversary, and K is for “Kelly” (according to her).

Short video of today’s flight:

-Rob and Kelly
http://kochman.net/N819K/

P.S. (from Rob) The airplane was definitely my passion, but there’s no way I could have done it without Kelly.  She put up with more than I could ever ask for and kept me sane during the low points of the building, but she also took it a step further.  These pictures really show it was a team effort. http://kochman.net/KellyAirplane/