Longest service interval-which turbine?
 

Have an odd question,
What turbine can go the longest without a service call?
I an researching this because I am working on a non-rc project that a turbine would be perfect for.
The older AMT's I hear can sometimes go 100 hours before service?

Just looking for info, and the larger the turbine the better.
Thanks

I think almost all manufacturers recommend 25 hours. If you do the math, for an average flight time on a jet, that gives you roughly 250-400 flights before service.

If I remember correctly, the AMT 280, 400, and 450 had a service interval of 50 hours. That may have changed over years.

Good info. i ask these questions because my project might require the turbine to run for 1-2 hours at a time. Maybe more.

IQ-Hammer also has a 50 service interval. On the other hand, some folks just keep flying their turbines without regard to service interval. JetCats and AMT's have been known to go 100+ hours without servicing.

Once they are out of warranty, service hours really don't matter. You wait until it fails, have starting or running issues. Bearings usually warn you, and that is the main reason of the service. If you aren't using it to fly in a model, I wouldn't think that it matters, especially if you are looking for an older engine that is already out of warranty. Buying used, make sure you see it in person and see it run. The life time warranty engines you must meet their service requirements to remain under warranty. Just know that those engines aren't truly warrantied for life. One, when they build new model of engines, those companies don't make parts for the older and the obsolete ones. And, warranties are only as good as the longevity of the company. Which in this business is rarely a life time.

AMT netherlands, by far(very) the RR of rc turbines!!

Behotecs are also 50 hours.

P-120 2005 purchase still running great! Just glow plugs and regular cleaning of manifold. All original pump and selonoids. Ver 6.0.

RCFlyerDan,

Lets think about that statement you made "Once they are out of warranty, service hours really don't matter. You wait until it fails, have starting or running issues" That would be an accurate statement if you planned on throwing it away once it blew up. Preventive maintenance can make a turbine last for easily 10+ years of service. If you let it run until the bearings fail, most turbine compressor and turbine wheels have a very tight tolerance and you will grind the compressor wheel into the intake cover and the turbine wheel into the NGV ruining them. Those 2 items alone will cost anywhere from $500.00-$1,200.00 to replace along with any other collateral damages. Or I have a better idea, pay the $300.00-$400.00 interval service fee when ever it is recommended (bearing change, cleaning, balancing, tune up) and keep a good reliable engine for many years!!

my .02

Dirk

AMT Netherlands - been flying them since 1997 and have never had to service any of my engines.

Jan

Sums!
 

Your maths is a bit out!
Typically even a 5 minute flight takes a 10 minute engine run. That give 6x25=150 flights between services.

Really
 

Do you REALLY mean the larger the better?

In that case you could try these people:

https://www.rolls-royce.com/about/ou...ent.aspx#sense
Seriously though, larger engines will tend to have much longer service intervals - once you get out of the usual "model turbine" domain. Jetcat and AMT both sell some much larger engines at a price eg Jetcat 400 or AMT Titan or Nike.

However these engines are expensive $10000-$30000.

Once I start hearing pops, I dissemble mine and let it soak in PB Blaster for about a week. Carbon build up comes right off.

AMT Netherlands is 100 hours.

My reasoning for what I said is for the following. There are only two companies that I am aware of that give a "Life Time Warranty". I have flown one of them with a student. They seem to do a lot of R&D in the field. Had a buddy buy a brand new one this year here on the field, and had to send it in for repairs after two runs. Yeah, it had the "Life Time Warranty", but he lost flying on his new jet for a month, cost of shipping, etc. And, I actually think he had to send it in again before he maiden the jet. Not a fun first experience for that owner. The other engines on the market are mostly 2 or 3 year warranties or 25 hours, which ever comes first. I see the math, but I do think that it does take more then 150 flights between the 25 hours. Maybe 200-250. I am talking off of the cuff, but I would say that 20-25% of the engines sold per year sit on the shelf waiting for the owner to assemble his jet, or do to a true build. That engine becomes out of warranty the following year, or two if it is a 2-3 year warranty engine. And unless the owner is an aggressive flier, someone that flies more than twice a week, more than 2 flights per day, there is a low amount of flight time on that engine when the warranty runs out. I think the average pilot flies two flights per day and one day a week. If you live somewhere that you can fly year around, that is 104 flights per year. If you don't and live up North, you only have 6-9 months to put those hours on the engine. Takes longer to get to the 25 hours. To me, that is even an aggressive year per engine. The engine manufactures know, but I would guess that approx. 50% of the engines that are sold per year are wrecked prior to the 25 hours. This voids the warranty on the 2-3 year warranty engines. They get repaired, if it is cost effective, and there are parts. Depending on the pilot as to if it makes it to the next 25 hrs. I am guessing from what I understand on the "Life Time Warranty" engines, if you wreck them, you must pay for the parts to repair it back to new and pay a service fee of around $250 to "Buy back into the Warranty". But, truly don't know. Not sure if there is an additional labor charged on top of that for the wreck repair. Dirk, I think you can fill that in? Then, there is shipping to add in on some of the engines. Mine go to Germany, so there is an additional $300 per repair, and the last time I sent it there for new bearings and adjustments, cleaning, was due to the sand here according to him. Did not make it to the 25 hrs and was not wrecked. That was a $750 bar bill, plus the $300 and it comes to a $1000. Since it is a 180, it was worth fixing. I have had that engine for about 4 years, maybe longer, and it has yet to get to the 25 hours. I did notice the last time I looked, it was in the low 20's on hours. Since it had new bearings, cleaning and adjustments around 18 hours, it is good until approx. 43 hours. Another 3 or more years from now. The next repair service, it is now an outdated engine, parts may or may not be available for the next wreck or even 25 hr service. Cost more than 50% of the cost of a new one, I'll junk the engine and buy a new one. By that time, the engine won't be worth anything on the used market and I am going to run it until I wreck it or have running issues. Have two of these engines and they start ever time I am at the field. The way the industry and technology is advancing in the hobby, most older engines will not have parts, and the owner will have to purchase a new or used engine. The other approx. 50% of the engines that actually make it to the 25 hours, depending on how many years that it takes to get it to those 25 hours, it may not be worth the market value to fix it. IF the manufactures have and still make the parts. I found that out the hard way with JetCat(only company I will mention) back when I used to fly them. Had an 80 that according to Bob. W, didn't have parts to repair it, so he gladly sold me a 120. I don't like to buy a used engine, but if you wreck your engine and can't afford a new one; you have look at the cost of repair vs the used market. I don't want to have a repair bill bigger than the used market. So, this is my justification for running an out of warranty engine until it breaks.

Jetcat P-120, the Toyota of turbines, no dealer visits required.

Good info here, and already owning a P120 makes it even better.
If I had an extra $27,000 I'd buy a AMT Nike...but I don't! :D An amazing piece of kit it certainly is!!
Seriously though........I have heard the AMT's last a very long time. But regarding an earlier post, I can't imagine waiting until a turbine fails....someone could get hurt there...like fatally!
And I just don't want to throw away the engine like it's some electric foamy plane. I need to be able to use this thing for awhile.:D

But another thing to note, this is not going to be a flying engine, it will be in a utility type of operation and maybe running for 2-3 hours at a time.

Bennie built AMT , a bit heavy, but there is a reason for it. The Rolex of engines.

If I buy another Jet engine, it would be the Jetcat hands down.

Utility Engine
 

People who are looking at using the technology for "utility" are looking at using air-bearings to get around the service interval issue (and yes it is the bearings that are at the root of the servicing issue - since all the manufacturers use the same bearings service intervals are pretty similar).

These people are using the technology for utility purposes.
Bladon Jets | Micro Gas Turbine Engines

however I'm not sure if they have anything real.


Or you could look at the one outlyer in the field - the Swedish Hawk:
Hawk Turbine

Installation
 

Another point about non-flying engines is that you will need to think about heat dissipation. Turbines are not designed for long term, static, high throttle, running. The expectation is installation in an airframe that allows some through air cooling. This probably isn't an issue for the engine itself - the air flow inside the engine exceeds that on the outside - but it is an issue for the surroundings.

Also you must think about safety. A failed turbine wheel fragment closely resembles a hot bullet. Prolonged full power running in close proximity to people requires effective shielding. Steel or concrete are needed.

Wow - if you don't trust simple mathematics it sort of brings into question everything else that you said.

For the record my P20 ran out its first 25 hr service interval in 122 flights. Now admittedly there was a bit of test running in there but not 100 flights worth. To back this up I checked the runtime after every flight and it was typically 9-10 minutes, never below 8. This is for a very small model with short (< 6 minute) flights. Larger planes tend to fly for longer.

You'll NEVER get to 200 flights before 25 hours.

You guys are thinking too literally for engine failure and thinking catastrophic engine failure. Bearing failure is engine failure. Do you think the engine manufactures change out the blades every 25 hours or even 100 hours? There is nothing preventing an engine from having catastrophic failure the first flight out of 25 hour service. When the bearings fail, you have a core engine that doesn't run and money has to be spent on it. At some point, you aren't going to spend the money to fix the engine. A jet flying buddy here had his bearing fail on a NEW engine with less then 5 hours on it. Came apart in the air, fire on board. He was able to land the jet safely, but the fire still totaled the airframe. That engine was junked. Not sure if he got any warranty on the engine, but I know he'll never buy that brand again.
The hour meters are just a guide too. Change the ECU changes the hours on the engine. Unless that manufacture has moved the ECU to inside the engine. This is why buying a used engine is risky because you don't know if it has the original ECU. I had a JetCat and at the time only could afford one engine and swapped it between the two jets. I had separate ECU's for each jet. The hour meter read different with each different ECU. This is why it is so risky buying a used engine on the market. Hours may not be telling the truth. One of the "Life Time Warranty" company's even voids the warranty if you change ECU's for this reason. The engine hours are by RPM too, not an actual clock. So, the longer it idles or flies around at half throttle, you aren't putting the same hours on the engine as at full throttle.
So, waiting until it fails is no more dangerous then our current practices, because catastrophic failure can happen at anytime in the engines life.

Since time on the engine is done by RPM, this just tells me that you flew your P20 at full throttle a LOT! So, you CAN get 200 flights at reduced throttle prior to the 25 hours.