Familiarization tour of the Cozy Mk. IV, and UL520iS engine runs

In this video, I push the fuselage of the Cozy Mk. IV out of the garage, and demonstrate how to get into the plane and get it ready for a run of the UL Power UL520iS engine.
At 2:30 I misspoke. Of course it's an oil line delivering oil to the valve areas, not a gas line.
At about 14 minutes, I run the engine up to 1500 rpm and test the electronic ignition systems by momentarily shut off first the left, and then the right ignition system, looking for an rpm drop (there wasn't any) - watch the hand signals, before going to full throttle.
At the end of the video, I try taxiing and differential braking to make sure I can steer the plane with its castering nose wheel. This is the first time it has moved under it's own power!
Fun!

[@willcall9431]

I really hope the UL works for you. I was on the early end of engine production and mine had teething issues. Leaks, low voltage flywheel damage from starts. Hopefully they fixed those issues. The support from Robert was phenomenal however. Overall I think the UL is a great alternative.

[@savagecub]

Outstanding workmanship ! Thanks for posting !

[@GregoryACross]

Thank you!

[@paultaylor9939]

Looking good thanks for sharing

[@delschier1419]

Looks great! Flawless workmanship. Everything in the green. Doubles as a BIG leaf blower too.

[@GregoryACross]

I'm not sure my neighbor appreciated blowing half the leaves in my back yard across the creek and into his yard! I need to apologize to him.

[@stevebeschakis9775]

How to make friends in the neighborhood. hahaha

[@clydecovington3972]

I can see using a fixed propeller on a 520 engine for testing but I would definitely have a constant speed propeller to maximum efficiency and performance once completed.

[@scottfish6127]

Super job Greg. Keep going. My Cozy is looking for another UL520is partner.

[@GregoryACross]

Thanks, Scott! I appreciate the encouragement.

[@nickwills5288]

Looking good 👍🏼

[@GregoryACross]

Thanks 👍

[@marktayler7080]

Just occurred to me, you need a rear view mirror on there things to see “clear prop” before starting!

[@GregoryACross]

You're correct! It helps to have another set of eyes to see behind the plane at start time. Also, the view to the right is obstructed by the open canopy.

[@HighPowerOptionsTrades]

We need an update 🔥

Hi Greg, Did you get the engine mount from UL Power or was it custom-made?

[@GregoryACross]

Sean, my engine mount was custom-made, because at the time nobody made one commercially. I understand that UL Power (USA) now has a source of engine mounts. I suggest you contact Ray Lawrence at Kaolin Aviation. He's UL Power's technical representative here in the US. [phone].

Hello Greg, Because the UL Power engine is significantly lighter than legacy Lycoming and Continental engines, did you have to make any adjustments regarding center of gravity?

[@GregoryACross]

Yes, I did. I extended the engine mount 2", and shortened the prop extension by 2" so that the prop remained in the same relative position. With less weight on the back end, the maximum front seat capacity was reduced. Moving the engine backward helped restore that. (Remember that my installation is a pusher arrangement).

[@Cotz95]

Is the weight different enough to enable the addition of a constant speed prop? 😁

[@josephc.9520]

Ah shame you couldn't wait for the turbo that would be 220 ktas easily

[@GregoryACross]

I'm not so sure... upping the horsepower doesn't affect the air frame drag characteristics. Down low, it wouldn't make much difference, as drag goes up with the square of the velocity. But at 15,000 feet, you could be right! What I would expect would be fantastic climb rates! At this point, I wouldn't want to go to the extra expense and effort to make the change. I want to see this thing fly before I die!

[@PatrickMichalina]

@@GregoryACross If I build one I would get the turbo for those nice climb rates and full manifold pressure up at 15,000ft.

[@GregoryACross]

@@PatrickMichalina That sounds great, but prepare for sticker shock. The UL520-T Turbo version is pretty expensive compared to the UL520-iS model.

[@zackriden79]

I'm sorry there just not 50k wroth of engine there...

[@GregoryACross]

True... nor does it cost anywhere near that much. As aircraft engines go, it's a bargain.

[@John-rw9bv]

It's truly a crime that more people aren't recommended to use Subaru engines. Never the less he has a plane and I don't so what do i know hahah :)

[@majorchungus]

@@John-rw9bv People are scared off by Subaru engines in aircraft because there are a decent amount of people that tried but had too many issues making it not worth the squeeze to most builders.

[@majorchungus]

@@GregoryACross If you don't mind me asking, how much did you pay? I am contemplating putting the UL520 turbo on my Long Ez.

[@GregoryACross]

@@majorchungus Well under $30,000. But, mine is not the turbo version. Prices vary from country to country, so best to consult your local UL Power sales representative.