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UL520 new turbo 220 HP

Mike Houston

Active Member
I am looking to build my first plane. I really want a 2 seater touring type aircraft so the RV14 or 14A came to mind. However i live in europe and dont want to pay the huge prices here for 100LL that comes with a Lycoming engine.

I see though that ULpower are about to release their new 520 220HP Turbo engine. It struck me this could be a good replacement for the IO-390-EXP 215HP engine as it burns mogas up to 15% ethanol. Especially as the 520 is likely to have most of the power available upto height.


However one issue i see is the effect on CG. the 520 is about 30 kgs lighter than the lycoming, do more experience builders think this would be an issue? I may have to go for a europa elite + or Whisper 350 gen 2 if cant get a mogas power plant in the RV.
 
100LL that comes with a Lycoming engine

Not necessarily. Quite a few people, including myself, are burning MOGAS with their Lycos. Guess the main issue is a well designed fuel system to prevent vapor lock.

We have one -8 here equipped with ULPower Motor, and as far as I know, the builder is quite happy with. He had to position the engine a few inches ahead of an original position to satisfy the CG envelope. Same would apply to the -14 I guess.

Last but not least, the turbo. The benefits are known, getting rid of the heat whilst using the tight RV cowling can present some challenges.

Good luck in your endeavor :)
 
The RV-14 comes the improvement with RV kits that started with the RV-7 where the kits just keep getting better and more straight forward to build. Installing a different engine negates a sizeable chunk of that improvement. You will be the development engineer figuring out fuel, oil, cooling and intake air routings. Then you will have to solve all the minor development problems you didn't consider when you designed the installation. 30kg off the engine is significant. It will completely screw up your W&B. Your baggage capability will be low, like some RV-6s with a light engine and prop. There are work arounds but you will always be limited on the amount of baggage that can be carried. Loading any RV at the aft CG limit is not something to be considered lightly as the handling can be quite light in pitch. Outside the aft limit and it is possible to venture into pitch instability territory.

I guess the question is how much will you save by burning Mogas over the time & effort required to install the engine? If both engines burn overall 30 to 35 lit/hr (7 1/2 to 9 usg) what will be your saving at 40 hours per year? Are you prepared to spend several hundred build & development hours to realise that saving?

BTW the Europa Elite is still a paper aircraft, I wouldn't buy one until the initial few aircraft had got a few hundred flying hours on the clock. At least the Whisper is flying, although not clear from the website how many customer built aircraft have been completed. I would be sceptical of low build time numbers as many builders find the engine installation, electrics and finishing take almost the whole of the quoted build time quoted by Whisper.
 
The engine is just the first thing if you vary from the plans installed accessories.
Plumbing is always a headache with alternative engines, and I dont know if UL Power has come up with a true kit for FWF or not. Our last dealings with then was 2 years ago.
If youre living in Europe--you might be on your own for alot of items that are taken for granted in a plans built plane. Doubt UL has any install data on a RV14.
Tom
 
responses

Yeah all good points. I suppose if i could burn Mogas in a Lycoming that would be my preferred solution. DeeCee57 did you design your own fuel system or just put in the kit supplied stuff. I see this guy went out and bought one from TSFlightlines.

https://vansrv14project.uk/2019/12/13/section-31-fuel-system/

I reckon the difference between Mogas and 100LL here is about $4.50 a US gal. It starts to add up pretty quick, i suppose i would be better going with a kit that was built with ulpower 520 in mind or maybe the new Rotax 915is but i want something that get me and the wife to south france, Italy in decent comfort and cruise at 150knts ish

Lol:- just realised TS flightlines has responded what a helpful bunch you all are.

I see Darkaero are designing a plane with the UL 520IS in mind. But it seems more like a pocket rocket cruising at 270 mph or their abouts and a small cabin.

https://www.youtube.com/watch?v=3pkxNx4UYFs

But as you say i dont want to be the first to build anything
 
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Burning mogas is largely a function of engine compression ratio. Lycoming says 8.5:1 is the upper limit for the use of 91 octane fuels.

An IO-390 with lower compression would allow you to gain all the benefits of the RV-14's pre-made kit components while also giving you the ability to run mogas. Yes, you would sacrifice some horsepower, but what does that really mean for YOUR mission?

I'll provide one example for your consideration... I built a Glasair Sportsman with an 8.5:1 compression ratio, making 180hp. By contrast, the overwhelming majority of Glasair's Two Weeks To Taxi customers choose the IO-390.

So what to I lose in terms of performance compared to the IO-390 Sportsman? The answer is 'not much'. The 180hp engine doesn't get off the ground as fast, doesn't climb as quickly, and won't go quite as fast. For two identical Sportsman aircraft flying side-by-side, the IO-390 might provide very slightly better fuel consumption - maybe.

What do I gain in terms of performance compared to the IO-390? Lower engine weight so the airplane is a little sweeter in handling - other than that, one can hardly tell the two apart in flight, save for the points mentioned above. The IO-390 is a more expensive engine to buy and has cylinders which are MUCH more expensive to replace, like twice as expensive. And then there's the mogas thing... My last mogas for the airplane cost CAD$1.067/litre. 100LL at our airport is currently priced at CAD$1.81/litre. That equates to savings of more than CAD$26/hour. That's REAL money.

At the end of the day I'm very happy to not have the fire-breathing IO-390 installed in our aircraft. Being able to fly 50% more hours on the same fuel budget more than makes up for the slightly lower aircraft performance that comes from the lower power engine.

There is a Sportsman flying with the UL520 (sorry, not sure which variant, but it first flew nearly 5 years ago). He has high compression pistons so is supposedly making 200hp.
 
I looked into UL previously the RV14 is designed around a 4 cylinder so going to a six cylinder will involve a lot of development time on your end. Longer nose, CG, etc. The UL power folks at Oshkosh basically said it was not worth the effort.

If you start a kit now you might be at the engine install point where the Higgs Diesel will be available as a FWF kit. They will have an article in the kitplanes engine buyers guide when that comes out.

http://www.ac-aero.com/falcon-fl200/
 
I looked into UL previously the RV14 is designed around a 4 cylinder so going to a six cylinder will involve a lot of development time on your end. Longer nose, CG, etc. The UL power folks at Oshkosh basically said it was not worth the effort.

If you start a kit now you might be at the engine install point where the Higgs Diesel will be available as a FWF kit. They will have an article in the kitplanes engine buyers guide when that comes out.

http://www.ac-aero.com/falcon-fl200/

diesel is my dream engine. Jet A is about 35% of the price of 100LL around here and has about 30% more juice in each gallon. That would be sweet. Mind u i wonder what they will cost. Continental diesel seem to be crazy expensive and they wont sell them to experimental builders
 
Burning mogas is largely a function of engine compression ratio. Lycoming says 8.5:1 is the upper limit for the use of 91 octane fuels.

An IO-390 with lower compression would allow you to gain all the benefits of the RV-14's pre-made kit components while also giving you the ability to run mogas. Yes, you would sacrifice some horsepower, but what does that really mean for YOUR mission?

I'll provide one example for your consideration... I built a Glasair Sportsman with an 8.5:1 compression ratio, making 180hp. By contrast, the overwhelming majority of Glasair's Two Weeks To Taxi customers choose the IO-390.

So what to I lose in terms of performance compared to the IO-390 Sportsman? The answer is 'not much'. The 180hp engine doesn't get off the ground as fast, doesn't climb as quickly, and won't go quite as fast. For two identical Sportsman aircraft flying side-by-side, the IO-390 might provide very slightly better fuel consumption - maybe.

What do I gain in terms of performance compared to the IO-390? Lower engine weight so the airplane is a little sweeter in handling - other than that, one can hardly tell the two apart in flight, save for the points mentioned above. The IO-390 is a more expensive engine to buy and has cylinders which are MUCH more expensive to replace, like twice as expensive. And then there's the mogas thing... My last mogas for the airplane cost CAD$1.067/litre. 100LL at our airport is currently priced at CAD$1.81/litre. That equates to savings of more than CAD$26/hour. That's REAL money.

At the end of the day I'm very happy to not have the fire-breathing IO-390 installed in our aircraft. Being able to fly 50% more hours on the same fuel budget more than makes up for the slightly lower aircraft performance that comes from the lower power engine.

There is a Sportsman flying with the UL520 (sorry, not sure which variant, but it first flew nearly 5 years ago). He has high compression pistons so is supposedly making 200hp.

Food for thought, Thanks
 
Cowl, mount, CG etc

All have to be rethought for each RV model considering ULpower. Currently there is a RV4 with the 520 being tested. Next phase is altitude testing / data gathering .
 
I'd use the term 'diesel' very loosely with the AC-Aero/Higgs engine. It is not a compression-ignition engine, rather a multi-fuel spark-ignition engine primarily targeted to the use of Jet-A.
 
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Has the Higgs engine flown yet? If so, how many flight hours so far in the test program?

Their site lists 4 engines (2 fours, an 8 and a 12 cylinder) all debuting in April 2021. That seems like a tall order to me.

Anyone have a scoop on this?
 
If memory serves, the UL engine's HP is at higher RPM (3000 - 3300) than the traditional 2700.

This limits prop choices, and also there isn't a provision for a prop governor.
 
If memory serves, the UL engine's HP is at higher RPM (3000 - 3300) than the traditional 2700.

This limits prop choices, and also there isn't a provision for a prop governor.

Yes as i understand it the 520 IS delivers 200HP @ 3300 rpm or 185HP @ 2800 rpm, however i believe that the new turbo version which is supposed to be released any day now is 220HP but i am not sure at what RPM. I think in this video he says the turbo will deliver this HP @2700 rpm

https://youtu.be/8cNmJATqNsw
 
diesel is my dream engine. Jet A is about 35% of the price of 100LL around here and has about 30% more juice in each gallon. That would be sweet. Mind u i wonder what they will cost. Continental diesel seem to be crazy expensive and they wont sell them to experimental builders

I've spent the past few months trying to find a Diesel option for the RV-14... there just isn't anything out there yet that isn't "COMING SOON!"

Continental will stop talking to you as soon as you mention you're interested in diesel.

I'm probably going to end up with a EFII/390 solution. I can always change the engine later, or just build another airplane when a diesel actually becomes a real thing that you can buy and not just slideware.
 
I am looking to build my first plane. I really want a 2 seater touring type aircraft so the RV14 or 14A came to mind. However i live in europe and dont want to pay the huge prices here for 100LL that comes with a Lycoming engine.

I see though that ULpower are about to release their new 520 220HP Turbo engine. It struck me this could be a good replacement for the IO-390-EXP 215HP engine as it burns mogas up to 15% ethanol. Especially as the 520 is likely to have most of the power available upto height.


However one issue i see is the effect on CG. the 520 is about 30 kgs lighter than the lycoming, do more experience builders think this would be an issue? I may have to go for a europa elite + or Whisper 350 gen 2 if cant get a mogas power plant in the RV.

Sling TSI may be an option. The money saved on a -7 or -9 will buy a lot of gas vs one of those. .
 
I installed a UL 130hp in the Zenith 750 I built. I was very impressed with the quality of the engine, ease of use and support. It literally starts like a car, turn the key and go, no cooling issue, of course Zenith had a FWF already designed. I did check with UL Power for my RV14A and they stated what has already been discussed, design your own FWF, weight is an issue in the RV.
 
diesel is my dream engine. Jet A is about 35% of the price of 100LL around here and has about 30% more juice in each gallon. That would be sweet. Mind u i wonder what they will cost. Continental diesel seem to be crazy expensive and they wont sell them to experimental builders

The energy density of diesel is actually closer to 15% higher than gasoline per gallon.

But diesel weighs 7lb/gal vs 6lb/gal for gasoline.

So when you consider energy per pound, which is what matters when calculating how much oomph you can fit in the wings within your W/B numbers, they pencil out pretty equal.
 
The energy density of diesel is actually closer to 15% higher than gasoline per gallon.

But diesel weighs 7lb/gal vs 6lb/gal for gasoline.

So when you consider energy per pound, which is what matters when calculating how much oomph you can fit in the wings within your W/B numbers, they pencil out pretty equal.

I am more interested in energy per $ than energy per pound. Given that energy per pound is similar it seems the more important metric. Where i live jet A is about 40-43% of AVGAS. The fact you get 15% more energy per unit in theory should lead to a DIESEL/JETa aircraft costing 35% as much per mile travelled as a similar aircraft using 100LL. That adds upto real money.

In UK If you fly 70hrs a year in an aircraft using 8.5 us galls an hour at £1 =$1.35

AVGAS = $5100 Approx
Mogas = $3360
Jet A = $1875 allowing for 15% more energy per unit.

5 years and you are talking about real money. I think in europe if the Higgs engines are within $10,000 to $15,000 of a similar power lycoming plant and they show decent safety characteristics there will be a queue a mile long at the Higgs dealer
 
UL results

Ray Lawrence, the UL importer, is a friend of mine. His 220 HP UL turbo has so far, maintained 36” up to 13,000’ ! He now has intercoolers installed and with his recently acquired oxygen, plans to go near 18,000’ for further tests..stay tuned...😊

Regards,
 
A modern engine

I'm watching with interest. Looking for these modern engines to run a few thousand hours reliably, technological advances are exciting.

Next, examples of electrically governed props being used with these engines and learning about maintenance cycles/reliability of these systems in the experimental world.

Maybe UL will build FWF kits for RVs since they are one of, if not the most popular experimental aircraft built.
 
The RV-8 mentioned in one answer, flying with an UL engine:
- Needed an additional engine mount, the one from the engine supplier was not strong enough.
- It flew
- Had an unexpected engine shutdown, luckily on taxiway
- Somehow engine is running very rich

Now it sits in the hangar corner ...
 
Ray Lawrence, the UL importer, is a friend of mine. His 220 HP UL turbo has so far, maintained 36” up to 13,000’ ! He now has intercoolers installed and with his recently acquired oxygen, plans to go near 18,000’ for further tests..stay tuned...😊

Regards,

What type of plane is he running the engine on?
 
FWIW

I know absolutely nothing about UL Power and so I don't comment on them.

But I will echo earlier comments about increasing the complexity of the build. I would estimate any change to the kit design adds many many times to the complexity, often in ways you would never expect.

My own experience with what was sold as a bolt on and go engine based on the Subaru STi from what was then a Florida based company ended in failure, and a loss of $10,000's. It nearly killed the whole project, and certainly put it back many years. I count myself lucky, a friend who also bought the same package got it flying in his RV8, after much work, and expense, but ended up crashing into a forrest when the engine suffered multiple internal failures in flight.

Now I am happily flying behind an Aerosport Lycoming. And the guy who crashed his RV8 walked away mostly uninjured.

Caveat emptor
 
RV-4

What type of plane is he running the engine on?

Mornin’ guys.Ray has the engine in his RV-4, turned out to be a Rocket in performance! I was just there a couple of days ago and saw the longer motor mounts and cowls already developed for the RV-8, 7 ,9 and -12.

I’m putting one in my RV-12 shortly and the other -12 has incredible performance with its 130 HP UL engine.

Regards,
 
Mornin’ guys.Ray has the engine in his RV-4, turned out to be a Rocket in performance! I was just there a couple of days ago and saw the longer motor mounts and cowls already developed for the RV-8, 7 ,9 and -12.

I’m putting one in my RV-12 shortly and the other -12 has incredible performance with its 130 HP UL engine.

Regards,

Very interesting, there new Turbo 520 would be suitable for the RV14 and maybe the RV 10. 220HP @ 8000 ft must be up there with the IO-540. Do you know if they are looking into FWF for those planes, those are the ones I am interested in.
 
FWIW

I know absolutely nothing about UL Power and so I don't comment on them.

But I will echo earlier comments about increasing the complexity of the build. I would estimate any change to the kit design adds many many times to the complexity, often in ways you would never expect.

My own experience with what was sold as a bolt on and go engine based on the Subaru STi from what was then a Florida based company ended in failure, and a loss of $10,000's. It nearly killed the whole project, and certainly put it back many years. I count myself lucky, a friend who also bought the same package got it flying in his RV8, after much work, and expense, but ended up crashing into a forrest when the engine suffered multiple internal failures in flight.
Now I am happily flying behind an Aerosport Lycoming. And the guy who crashed his RV8 walked away mostly uninjured.

Caveat emptor

Wasn’t that his 4 engine ‘issue’ ? Sometimes a Lycosaurus is a better option. :rolleyes:
 
I know this isn't a UL520T but it's a good YouTube channel documenting the build of an RV-7 with a UL520iS.

https://www.youtube.com/channel/UC2um0667xGuH284TJOFYvSA

I am planning an RV-8 build and I am looking at the UL520T. The price is close to an IO-390, it's a full FADEC engine, Electric CS Prop, it weighs the same as an O-320 so the CG should work out without extending the nose, It run on 93 octane auto pump gas up to 15% ethanol, the Zenith guys are loving the UL350's, I think this is getting t be a really viable alternative.
 
I know this isn't a UL520T but it's a good YouTube channel documenting the build of an RV-7 with a UL520iS.

https://www.youtube.com/channel/UC2um0667xGuH284TJOFYvSA

It run on 93 octane auto pump gas up to 15% ethanol, the Zenith guys are loving the UL350's, I think this is getting t be a really viable alternative.

Getting a engine running on ethanol laced gas is not a problem. But make sure the rest of the fuel system won’t vapor lock with ethanol. Cars solved that with in the tank fuel pumps and that would be a good way to solve it in a airplane too, maybe. Look out for some untintented surprise with any fuel system mod.
I built my -8 to run on ethanol gas in case I have to use it in the future. So far not necessarily since we have non-ethanol boat gas in this area. I put the fuel pump as low as possible in the fuselage, avoided 90* AN fittings, installed a fuel return line limited to 7gph and put a cooling shroud over the pump. Used AFP injection system that is ok with ethanol.
 
Getting a engine running on ethanol laced gas is not a problem. But make sure the rest of the fuel system won’t vapor lock with ethanol. Cars solved that with in the tank fuel pumps and that would be a good way to solve it in a airplane too, maybe. Look out for some untintented surprise with any fuel system mod.
I built my -8 to run on ethanol gas in case I have to use it in the future. So far not necessarily since we have non-ethanol boat gas in this area. I put the fuel pump as low as possible in the fuselage, avoided 90* AN fittings, installed a fuel return line limited to 7gph and put a cooling shroud over the pump. Used AFP injection system that is ok with ethanol.

Thank you, very valid point about making sure the entire fuel system is up to ethanol exposure. I've added some notes about this to my project plan.

ULPower engines use a high pressure fuel injection system and an open fuel loop with return lines so fuel never stops flowing past the injectors. If any fuel vaporizes during a hot start it will be out of the lines by the time you finish your engine start checklist and turn the key.

Note that the ECU can manage the fuel pumps or they can be manual. Just like your car you can set them to turn on with key on and off with key off or engine stop for safety.
 
Thank you, very valid point about making sure the entire fuel system is up to ethanol exposure. I've added some notes about this to my project plan.

ULPower engines use a high pressure fuel injection system and an open fuel loop with return lines so fuel never stops flowing past the injectors. If any fuel vaporizes during a hot start it will be out of the lines by the time you finish your engine start checklist and turn the key.

Note that the ECU can manage the fuel pumps or they can be manual. Just like your car you can set them to turn on with key on and off with key off or engine stop for safety.

EFII and SDS do exactly this and are designed to handle ethanol laced fuel. With continuously flowing fuel via fuel return lines and a high pressure fuel rail, vapor lock is essentially impossible. I’m running one of these systems in my -8 and I’m also incorporating it in my -14 build. This, along with the electronic fuel injection and electronic ignition, really modernize these old technology air cooled engines.
 
Getting a engine running on ethanol laced gas is not a problem. But make sure the rest of the fuel system won’t vapor lock with ethanol. Cars solved that with in the tank fuel pumps and that would be a good way to solve it in a airplane too, maybe. Look out for some untintented surprise with any fuel system mod.
I built my -8 to run on ethanol gas in case I have to use it in the future. So far not necessarily since we have non-ethanol boat gas in this area. I put the fuel pump as low as possible in the fuselage, avoided 90* AN fittings, installed a fuel return line limited to 7gph and put a cooling shroud over the pump. Used AFP injection system that is ok with ethanol.

Almost exactly the same for me. Local "98" mogas does not have ethanol, and we have UL91 on my home field. I have not yet run any ethanol in my fuel systems, but imagine my surprise when the Andair fuel pump SB came out saying that we should not use fuel with ethanol since the epoxy used in the pump somewhere seems to be affected by ethanol. Even if you do your homework you can get a surprise.
 
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