UL POWER w/ ELECTRIC CS PROP! ??? NEED IMPUT

[rv6ejguy]

Originally Posted by Chkaharyer99

From their website: http://ulpower.com/en/engines/ul520/ul520isa

"The UL520iSA is the ultimate aerobatics engine.
A modified engine casing, oil sump and oil pick up system, designed by our very own ULPower team, and an additional inverted oil system allows the ULPower engines to fly inverted.

This inverted oil system copes with potential greasing issues. The oil pick-up tube in the oil sump is mounted with a hinge joint. While climbing or diving up to an angle of 90?, the oil pump can pick up the oil from the sump without any problem.
The oil inverted valve can change the pick-up direction while climbing or inverted flying, this means that the oil is coming from the top of the engine casing (which is now the lowest point). The large (but light) ?oil air breather? prevents the oil from leaving the engine.

The fuel injection system (instead of carburetor) prevents the engine from stopping or losing fuel when flying inverted.
IMPORTANT REMARK: modification in your fuel tank is needed to prevent engine from sucking air.

Thanks to our electronic RPM limiter, ULPower engines can fly inverted for hours and hours without danger of over-running.

Oil capacity : Oil sump must be filled with at least 4 liter oil (0.US gal)."



I sure would like to hear more about the ULpowered RV-4

I know the UL engine has been used in Europe for aerobatics, I was more concerned that the electric prop may not be so great for that purpose. Some like the MT have a relatively slow pitch change mechanism.

[David-aviator]

Originally Posted by taverroi

The Lord declares that "There is Wisdom in a multitude of Counselors" I believe Him!

Fire away, Im all ears!!

Tango

There is wisdom only if there is consensus. Beyond that lies confusion.

You have been involved with 6 RV projects, why is this such a tough decision?

Or are bored with Lycoming?

If so, go for it. I've been there and done that.

It was an interesting, expensive experience.

[Bdalporto]

I do like the idea of the UL engine. I was think of one for a Wittman Tailwind. I think you better look close at the weight and balance with that engine. Most RV7's are a little tail heavy with an O-360 and a fixed pitch composit prop. Take another 50 lbs off the nose and you may not be able to carry much baggage. Just my 2 cents.

Brian

[Ralph Inkster]

He'll need a custom mount anyways, so pushing the engine forward to maintain C of G is a given. Think of the sleek custom turbine looking cowling he will end up with.

[kamikaze]

There's a FWF kit for the RV-7 from Kaolin Aviation Services LLC, including the mount, no *need* to go full custom ...

[WAM120RV]

Hi

I am currently rebuilding my RV9. My plan was to remove the 0-320 from my RV4 complete with sensenich prop and put them in the 9. Then buy an 0-340 and a whirlwind prop and stick that in my 4.

Then I heard about the UL engine........ 40 lbs lighter and either 180 or 200 HP.
Now that is very interesting. I then read AXO's comments about his 0-340 which have put me off that engine.

The UL engine sounds great until you factor in the revised engine mount, 11 inch longer cowl, although I understand these will be available from the UL supplier. The problem is that RV's were designed to accept heavy (by UL standards) engines.

Saving 40 lbs is great, six cylinder smoothness is great and provided the conversion kit ( engine mount extension, cowl are available from UL) it should not add too much work. However, what effect having the moment of inertia from the prop 11 inches further forward from the C of G would have during aerobatics is well beyond my ability to calculate.

I do know that Ray at UL is negotiating to buy an RV7 as a test bed, so he is the man to speak to.

[TS Flightlines]

Ray was working on engine mounts, cowlings, etc when we did some FWF hoses for his Rv4.
I think RV conversions are still in the prototype stage--we know ---kinda-- what the FWF hoses will be, but nothing set in stone.

Tom

[rvbuilder2002]

Originally Posted by WAM120RV

However, what effect having the moment of inertia from the prop 11 inches further forward from the C of G would have during aerobatics is well beyond my ability to calculate.

Valid questions that should be considered.

Probably deserving even bigger consideration is what it might do to spin recovery? Particularly at more aft C.G. positions.
Even if the moment of inertia isn't much different that it is with the Lyc., the additional flat plate area of the much longer cowl, fwd of the C.G. still has the potential to negatively influence spin recovery.

All stuff to consider when experimenting.........

[Naigool]

As I'm also considering to install ? UL power engine on my RV7 project, My question on the 3-4 previous reply is: the rocket has also a longer cowling ... so why th? UL RV7 will perform less aerobatics than a Rocket??

[rvbuilder2002]

Originally Posted by Naigool

As I'm also considering to install ? UL power engine on my RV7 project, My question on the 3-4 previous reply is: the rocket has also a longer cowling ... so why th? UL RV7 will perform less aerobatics than a Rocket??

I was one of the last posts but I didn't say it would have less performance doing aerobatics.

I said it could have an influence on the spin recovery characteristics.

Yes the rocket has a longer cowl than the RV-4, but it also has a different fuselage so it is not a good comparison to just making the cowl longer on an RV-7.