REFLECTOR: Flight testing going well...18hrs in, new video

[Jack Prock]

Hi Geoff,

Before you go chasing the EGT on one cylinder, you should watch http://www.eaavideo.org/video.aspx?v=1316946190001
He gave a talk on EGT’s at Oshkosh that was very interesting. It was about the mistakes people make with EGT’s and what
they really mean if anything. If your CHT’s are fine, you should be fine. 
It is a bit long, but I highly recommend it before you start ripping things apart.
Jack
From: Geoff Gerhardt 
Sent: Thursday, September 27, 2012 4:31 AM
To: Velocity Aircraft Owners and Builders list 
Subject: REFLECTOR: Flight testing going well...18hrs in, new video

Guys, 

Flight testing is going well, I've got about 18hrs in.  I'm still not able to just go out and fly - always little fixes and tweaks (that's the fun part for me, tho).  I have learned, tho, not to immediately try to correct an issue, but learn more about it first.  I've been chasing a hot cylinder and have been trying to cool it with better airflow.  After reviewing data logs and confirming it on my last flight, I now realize that its likely a combustion problem.  The EGT for that cylinder is always high.  Because of my aggressive airflow modifications, even in spite of that high EGT, the CHT is ok now.  I'm going to pull out the injector nozzle this weekend and give it a good cleaning.  If that doesn't work, I may try to ream it out a little.  I tried to put an oil collection reservoir as I was tired of wiping oil off the cowling, but it introduced too much back pressure, and all of a sudden I had a bunch of oil leaks to deal with (a rather nasty surprise of seeing oil all over the inside/outside of the cowling after a 2.5hr flight).  Got all those cleaned up and removed the oil recovery system.  I think I'll try to vent the breather into the exhaust.

Other than those issues, its been going pretty well.  I've been playing with fuel settings, altitude and efficiency.  I typically head up to 8-10,000' and run LOP.  At 10k' I am usually ~150ktas, and 8gal/hr.  I love the high-speed descent into the airport.  I report 10mi out to the tower and I'm in the pattern in no time - I think they're getting used to me zipping in as opposed to the C172's and warriors they're used to.

Here's a recent video I took taking off with a belly-mounted camera looking back.  Its kinda neat in that it looks like I'm zooming the lens as I gain altitude.  Yes, I know, it takes me a long time to get off the ground.  I actually have another prop coming that might help.  A Cozy owner had a left-turning Catto that he no longer uses.  Its a 64x76, mine's a 66x74.  I suspect it'll get me off the ground much quicker.  He didn't want much for it, so it'll give me a backup - I'll send mine back to Catto at some point to get it repitched or just keep it for a long-range cruise prop as it is.

Geoff
(I uploaded it in high-res so make sure you switch to 1080p)
http://www.youtube.com/watch?v=JhNZBc-inbw


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