MKIV Flight Testing

[C5Engineer 1170]

I now have 10 hours on my MK4. See this thread for more about the details of this plane.

So far I am pretty happy with the airplane. After filming some take off and landings, it confirmed my suspicions that the tailwheel spring was too tall. I had it cut down by 2" and that helped out quite a bit with shortening up the takeoffs and landings. So far it's a least as slow as my B model STOL wing and about 10 mph faster on top. The roll rate is quicker with the extended wing. Overall this airplane feels much more stable than my B model. It'll fly hands off very easily. I'm very happy with the rigging. Last Sunday I flew 80NM up to another airport in order to gather some cruise data. On the way home I started having my doubts that my left tank was feeding. I had plenty of places to land so I didn't worry too much about it. Towards the very end of the flight I had a little pucker factor about how much fuel I had left in my right tank. Below you will see what the culprit was. There is a T fitting that joins the two tanks outlets together before it comes out of the wing root. This crud was inside the T. It looks like some polyethylene drill shavings. I did flush the tanks and flow test them so I'm thinking maybe this crud came loose after flying it a few hours and running 20-30 gallons through it. Either way I drained it all and I'm pulling all the plumbing and flushing it all again before I fly it again. On my B model I take the 90 degree fittings out each year at inspection and thread in a straight fitting that is fed into a bucket and I flush the tanks that way. It takes VERY LITTLE debris to impede the flow with these gravity fed systems!!

Short vid I did to watch the tail feathers and TW.

 

 

Edited 13 Mar 2018 by C5Engineer

[PW_SD 1]

Joey

Glad you found the debris before losing all your fuel flow.  Sharp plane!  Hey- what is the make/model of the circular VSI OAT Altitude instrument next to your Avionics switch?

Phil

[PW_SD 1]

Ah, found it in your earlier post: Belite multi.   Curious how you like it.  

[C5Engineer 1170]

Ah, found it in your earlier post: Belite multi.   Curious how you like it.  

I really like it. The temp sensor wires need to be extended to move it anyplace useful.  My only other complaint is when you adjust the altimeter setting the numbers change really slow. If you’ve had a big swing in pressure it can take a while of holding the button down to set it. It appears to be very accurate and the Density Altitude feature will come in really handy this summer. 

[Avid Randy 50]

Joey

Glad to hear your having Great results with the wings!  I'm waiting back from Mark at new Avid to get my extended kit so I can install when I get that far.  It will be Great to have both worlds STOL and extra speed!

Not good to hear you almost had an incident even after doing all the cleaning out of the tanks.  That will make me want to clean it out several times!

Awesome to see the little one involved!  Can't wait to let my girls sit in it and go for a ride!  Plane looks Great too BTW!  

Cheers Randy 

[C5Engineer 1170]

I just finished pulling all the plumbing out of the wings and flushing everything AGAIN! Not sure where all the crap came from but it needed it. I also attacked another squawk I had today. My left wing nav light quit working. I assumed it was a connection in the fuse or my solder joint. After an hour of shooting wires and troubleshooting it's my Whelen assembly that is bad. I hooked it straight to 12V and no workie. Hoping they will replace it. They had less than 10 mins of time on them. The strobe still works just not the nav light on that one side and it's an a one piece assembly. No way to really replace anything. I also lost my altitude readout on my Microair Transponder. The encoder is a AK-350 AmeriKing. It uses a serial type cable to connect the two. I'm wondering if the encoder is TU as it was displaying altitude for the first 8 hrs of flight. What are you guys using for an encoder? Microair sells one but it's $365. I filled the plane to the brim with fuel today and holds just shy of 22 gallons with the 4 Ridge Runner Polyethylene fuel tanks. That's a solid 3.5 hrs plus a healthy reserve with the fuel sucking 582. With the 912 UL I'm looking at 5 hours of flight time. 

[ChrisBolkan 130]

if you ever install the 912