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Okay, not technically the first flight but close.

I purchased N153TD earlier this year and it had only been flown by the builder, David Jones aka Stogie6, one time that I know of.

Anyhow it hasn't been through phase1 testing and I started today.

Great first flight with just a couple of issues.

On take-off it hesitated at mid-throttle. I went to full throttle and it ran fine. Clearly still have some tuning to do.

Flew it about 2 hrs at 5000msl around 3000rpm. This should cover breaking the engine in if it hadn't already been done.

At about 3000msl I was practicing a pattern approach and put in one notch of flaps. Went to put in the second but couldn't get it out of the first notch. It was air pressure so something to watch on the next flight.

All in all a very great day.

Greg

Congrats Greg! Hopefully David is well, haven't seen him around recently on the forums.

VillaAir wrote:At about 3000msl I was practicing a pattern approach and put in one notch of flaps. Went to put in the second but couldn't get it out of the first notch. It was air pressure so something to watch on the next flight.

Sounds like a pretty good start overall. Congrats. How fast were you going during the flap test? I've never noticed anything like that on mine, but I don't typically use over 90 mph for flap speeds. Maybe have someone help hold some pressure against the flaps on the ground to simulate air pressure and make sure there's nothing funky going on with the mechanism.

I've flown several AeroVees and they all idle very rich. No matter how much I tune them, I cant seem to get it really better. Ive become accustomed to it. I lean for taxi and it helps a lot. If it isn't leaned, it stumbles as it accelerates. That's probably what you saw. I fly off a full length runway (+4000 ft) so Its never an issue. once it gets to 3000 rpm and is smooth, I commit. During testing, Ive aborted there with plenty of runway to stop.

The flaps are rough to deploy at speed. Make sure you are in the white arc. I even wait until I'm a little slower because they can be difficult. Good luck and keep us posted :)

Scott Todd wrote:I've flown several AeroVees and they all idle very rich. No matter how much I tune them, I cant seem to get it really better. Ive become accustomed to it. I lean for taxi and it helps a lot. If it isn't leaned, it stumbles as it accelerates.

I've only flown 1. We have a #2 needle. My AeroVee runs great at idle. Runs great at WOT and everywhere in between. I did experiment with a #2.5 needle when I added fresh air induction, and it ran a lot like you described.

The problem with leaning for idle is there is not much flow, so not much effect until the edge of fuel cutoff. Better to adjust the needle so it's happy at idle and needs some leaning at WOT.

My AeroVee is unhappy when too rich.

I had the flap handle problem happen to me. The air load on the flaps causes the flap handle to twist slightly and puts tension on the handle against the notch. I removed the flap handle, put a slight opposite twist in it in a vice and reinstalled. No problem since.
Tnhelm
OneX 0137

I was wondering if the timing needs adjustment.

I thought that I might be too lean, but from what you guys are saying, sounds like too rich. I'll continue to tune and will go to #2 needle if I can't get there.

Great tip on the flap handle, I'll check this weekend to see if that's the problem.

Glamour shot of the first flight

VillaAir wrote:I was wondering if the timing needs adjustment.

I thought that I might be too lean, but from what you guys are saying, sounds like too rich. I'll continue to tune and will go to #2 needle if I can't get there.

N153TD First Flight.png

So you have the #2.5? I would really recommend the #2. My first couple flights were a little lean, I was over 1500F at WOT. A couple of adjustments and I found the sweet spot. Runs a little rich with the mixture fully in. Will gain a little RPM when I lean.

Regarding the timing, did you fly at all on just one ignition? The magnetrons are fixed timing. It's in the manual - fly and stabilize on the primary only, then the secondary only. The temperatures tell a story. I set my secondary with a timing light.

Great picture!

I did some experimenting with needles, making seven in total. I made the needles from .125 drill rod, grinding the tapers on a surface grinder using a Sine plate. I found the three needles supplied were slightly under size on the diameter. The needle has two, what I call, sweet spots. One for idle and one for wide open. The needles, 1 through 3, have different angles of taper. As the angle increases, the two sweet spots get closer together. I found the wide-open sweet spot to be at about .082 needle thickness. And the idle sweet spot is nearly at cutoff. The ideal needle has both these spots located within the slide movement from idle to wide open. In the beginning I tuned for wide open like Sonex suggested. With the #2 and #2 1/2 needles I still had to lean the mixture to get a decent idle. As it turned out, my #7 had almost the same measurements as the Aero Injector #3. So, I tried the #3 and my problems were solved. My wide-open setting was made with the mixture about halfway out, so I had the chance to go leaner or richer. Take off was smooth at 3000 rpm and idle at 900 had no problems. I didn't have to lean when I pulled off the runway. I didn't change the mixture until I was at cruise and then only to lean for a good EGT. From one flight to the next I didn't touch the mixture.
When adjusting the needle. Mark the beginning of the taper, on the bottom of the needle, with a file. The shiny mark is more accurate and easy to see. Line it up at the edge of the opening and count the number of turns to your setting. Adjust the needle 1/4 turn at a time. That gives you a repeatable point to begin adjusting for a good wide-open setting. Just sayin.

Flew yesterday and checked the timing. No issues on that front so it comes down to adjusting the needle.

Thanks for all of the advice, I'll work on it as I move thought phase 1 flight testing.