Rotax Engines - Are we being (crank) shafted?

[Glenn Wilson]

This issue may have been done to death in the past but as I am considering returning to sport aviation I am going to put it out there to see what your views are.

 

A lot of people are pulled or pushed through the air by Rotax engines. And while this is generally about all the popular models available today, it is more specifically about 582s.

 

The price of a new 582 is around $7000 to $8000 plus or minus a few variables. To overhaul a 582 has been quoted at between $5000 and $5500, plus the cost of removal and reinstallation and freight to and from the overhaul facility. For the sake of a thousand or two dollars, a new engine looks like reasonable value compared to an overhauled one.

 

The TBO (time between overhaul) is, according to Rotax literature, 300 hours. Some organisations allow a 582 to run ‘on condition’ unless it is being used for training.

 

This does not add up.

 

A 300 hour TBO is roughly equivalent to 30,000 klms for a car engine. Hardly even run in. 30,000 klms on a Rotax powered BMW motorcycle is still low kilometres and imagine the outcry if a GS 800 needed an engine overhaul at 30, 40 or 50,000 klms.

 

How many 582s are running up 500, 600 or even 1000 incident free hours? RAAus and the HGFA should have stats on this.

 

Why is the TBO still 300 hours when I’m sure there is a verified history of many 582s running perfectly and within limits up to and past 500 hours?

 

Either the engines are dodgy, or components in them are dodgy, or someone is ripping off someone, or has a virtual monopoly that is allowing them to ‘take advantage’ fiscally of the people whose aircraft are fitted with 582s.

 

If the engines or engine components are dodgy then that would be reflected in the record of service difficulties or fault reports by the large number of people running 582s. Yes some of these engines fail pre 300 hours but in reality, not very many.

 

So why then is a $7000+ Rotax 582 engine mandated for TBO at 300 hours?

 

And why also have the HGFA and RAAus not resolved this financial burden on behalf of their members?

 

 

[kasper]

300hrs will not be amended by rotax. Their position is clear - two strokes are not their future so no need to extend even if evidence of safe op may exist.

 

RAAus and casa are not in the buisiness of looking after members by taking on risk by extending manufacturers limits and I can't see that changing - indeed RAAus is moving away from freedoms towards increased ar$3 covering through increased regulation and documentation.

 

Other countries do allow history or safe op or even on condition for hire and reward but oz is no longer the land of progressive or low reg flying.

 

Oh and those other countries are not exactly rule free - UK allow engines to run on condition and have manufacturers allow on condition even where rotax say overhaul.

 

The best option if you're two stroke restricted is replace the engine with new if used for hire/reward and sell on the expired engine to an experimental.

 

And pity the fate of airframes using the r503 ... money can't replace an engine at 300hrs that is no longer in production.

 

 

[Oscar]

FFS: how WOULD RAA or CASA be able to 'extend' manufacturer's limits? NO airworthiness authority ANYWHERE conducts independent engine certification testing - and engine certifying ( as per the ASTM regime) is purely the province of the manufacturer.

 

Certification - to an ICAO acceptable standard - is CONDUCTED by the manufacturer and AUDITED for Certification by the Airworthiness Authority. CASA does NOT decide to run any engine through the test regime - and RAA has no authority to do that. The suggestion that RAA is 'ar8e-covering' by not providing its own assessment of mandatory TBO times, is complete and utter BS - and Kasper, you know that..

 

Certifying to ASTM is entirely the responsibility of the manufacturer. Once again, RAA has NO authority to vary this. Kasper, you also know that.

 

So: please explain HOW RAA could increase a manufacturer's TBO? It would be very instructive.

 

 

[kasper]

FFS: how WOULD RAA or CASA be able to 'extend' manufacturer's limits? NO airworthiness authority ANYWHERE conducts independent engine certification testing - and engine certifying ( as per the ASTM regime) is purely the province of the manufacturer.Certification - to an ICAO acceptable standard - is CONDUCTED by the manufacturer and AUDITED for Certification by the Airworthiness Authority. CASA does NOT decide to run any engine through the test regime - and RAA has no authority to do that. The suggestion that RAA is 'ar8e-covering' by not providing its own assessment of mandatory TBO times, is complete and utter BS - and Kasper, you know that..

 

Certifying to ASTM is entirely the responsibility of the manufacturer. Once again, RAA has NO authority to vary this. Kasper, you also know that.

 

So: please explain HOW RAA could increase a manufacturer's TBO? It would be very instructive.

They don't certify is the simple answer.

Given the rotax 582 is not and never has been certified your concerns are a bit misplaced.

 

In other countries the non certified nature of rotax and other engines from hour 1 to hour 300 is recognised and the regulations ALLOW the use of non certfified engines on condition. From hour 1 to hour 400. 500. 600. Or more without limit based on the reality that from day 1 it's an uncertified engine.

 

In these regimes manufacturers are also free to allow owners to override certified engine manufacturers when fitted to Microlight or ultralight aircaft as the engine is then treated as uncertified but that class of engine is allowed.

 

And before I get any abuse between the eyes on unsuspecting paying students or such like the stall performance of the aircraft is such that paddock outlanding should be part of flight planning and flight consideration for the pilot and the reality is that there is not a logical case to allow ANY uncertified engine to be used and require certified engines remain certified when the class of aircraft is the same.

 

Eg. Uk where both certified and uncertified engines can and are used for hire and reward training in section s aircraft.

 

 

[Downunder]

I was quoted a 582 at 1600 hrs by an owner...... still in spec but but just thought he'd "better" change it as he had a spare engine ready to go. He considers 300 hrs "just broke in"...lol.

 

In a trike, flown by a hard core triker.....flown multiple times per week. If the weather was ok, he would fly.

 

Quite a few people say the secret is to not let them sit. I tend to believe this.

 

 

[Happyflyer]

FFS: how WOULD RAA or CASA be able to 'extend' manufacturer's limits? NO airworthiness authority ANYWHERE conducts independent engine certification testing - and engine certifying ( as per the ASTM regime) is purely the province of the manufacturer.Certification - to an ICAO acceptable standard - is CONDUCTED by the manufacturer and AUDITED for Certification by the Airworthiness Authority. CASA does NOT decide to run any engine through the test regime - and RAA has no authority to do that. The suggestion that RAA is 'ar8e-covering' by not providing its own assessment of mandatory TBO times, is complete and utter BS - and Kasper, you know that..

 

Certifying to ASTM is entirely the responsibility of the manufacturer. Once again, RAA has NO authority to vary this. Kasper, you also know that.

 

So: please explain HOW RAA could increase a manufacturer's TBO? It would be very instructive.

CASA allows aircraft to conduct "air work" with the engine having exceeded TBO on condition. Airwork covers flight training. Another example where RAAus have gone further than CASA.

http://services.casa.gov.au/airworth/airwd/ADfiles/enggen/eng/ENG-004.pdf See requirement 1.

 

 

[onetrack]

It's a well-known fact that large manufacturers sell their new products at low margins, and make up their losses on the new product, by ramping up pricing on the spares. This has been going on for decades, and it won't change anytime soon.

 

The CEO of P&W has stated on a TV interview in recent weeks that P&W sell their new jet engines at virtually cost, because they know they can make a $h*tload of money on the spares for those engines, as they are in service for around 20 years or more.

 

The problem is, the cost of overhaul of any engine incurs a very sizeable, and high cost, labour component. Most workshops charge $120 hr.

 

Then, with a worn engine overhaul, you have intensive cleaning (very important), inspection (even more important), parts procuring (can be painful and drawn out - 'oh, you wanted 12445-13366 part? - and we sent 12435-13366? Sorry, send it back, and we'll send the right one') - and finally, assembly and engine testing.

 

In a manufacturers factory environment, labour costs are low, all components are new, production and assembly is often automated, removing a lot of human error - and manufacturing has little by way of storage costs, inventory costs, or all the other costs associated with holding parts in stock - because manufacturing operates on JIT (Just In Time) principles.

 

If manufacturers had their way, there would be no engine overhauls or reconditioning. Your engine would be a sealed unit, just like a fridge compressor.

 

You would run the engine for X number of hours, or until it died - then you would undo 4 bolts, snap a few connectors apart, you would then bin the failed or time-expired engine, and go get a new sealed unit engine - at a cost that was well below the cost of repairing the old one.

 

It works for fridge compressors, and it would work for IC engines in aircraft. A sealed unit is protected from dust, weather, and all the contaminants that shorten its life - and what is the life of fridge compressors today? They nearly always last the life of the fridge.

 

 

[Jaba-who]

This issue may have been done to death in the past but as I am considering returning to sport aviation I am going to put it out there to see what your views are.A lot of people are pulled or pushed through the air by Rotax engines. And while this is generally about all the popular models available today, it is more specifically about 582s.

 

The price of a new 582 is around $7000 to $8000 plus or minus a few variables. To overhaul a 582 has been quoted at between $5000 and $5500, plus the cost of removal and reinstallation and freight to and from the overhaul facility. For the sake of a thousand or two dollars, a new engine looks like reasonable value compared to an overhauled one.

 

The TBO (time between overhaul) is, according to Rotax literature, 300 hours. Some organisations allow a 582 to run ‘on condition’ unless it is being used for training.

 

This does not add up.

 

A 300 hour TBO is roughly equivalent to 30,000 klms for a car engine. Hardly even run in. 30,000 klms on a Rotax powered BMW motorcycle is still low kilometres and imagine the outcry if a GS 800 needed an engine overhaul at 30, 40 or 50,000 klms.

 

How many 582s are running up 500, 600 or even 1000 incident free hours? RAAus and the HGFA should have stats on this.

 

Why is the TBO still 300 hours when I’m sure there is a verified history of many 582s running perfectly and within limits up to and past 500 hours?

 

Either the engines are dodgy, or components in them are dodgy, or someone is ripping off someone, or has a virtual monopoly that is allowing them to ‘take advantage’ fiscally of the people whose aircraft are fitted with 582s.

 

If the engines or engine components are dodgy then that would be reflected in the record of service difficulties or fault reports by the large number of people running 582s. Yes some of these engines fail pre 300 hours but in reality, not very many.

 

So why then is a $7000+ Rotax 582 engine mandated for TBO at 300 hours?

 

And why also have the HGFA and RAAus not resolved this financial burden on behalf of their members?

You have fallen to a trap when you start comparing a aviation engine to a car or bike engine and compare their functional life span.

 

There is not any automotive engine in any car that ever runs full throttle for five to ten minutes every time it's run then often for full throttle a few more times during the use cycle then at a cruise of 75% or so.

 

 

[fly_tornado]

regardless of the design, aircraft engines are made from the same materials as automotive engines. the cost of aircraft engines is high because people are prepared to pay a premium. Rotax has smashed Jabiru in OEM sales over the years because they are smart enough to see once you design an airframe around a power plant its impossible to change that power plant.

 

 

[poteroo]

regardless of the design, aircraft engines are made from the same materials as automotive engines. the cost of aircraft engines is high because people are prepared to pay a premium. Rotax has smashed Jabiru in OEM sales over the years because they are smart enough to see once you design an airframe around a power plant its impossible to change that power plant.

Have to agree with you there FT. Even Cessna, Piper, Beechcraft, Maule,... made the same mistake by Certifying with only one engine mfr and model. The smartest mfr I'm aware of is Dick Van Grunsven - who refuses to factory manufacture, produces a limited range of kits, and leaves everything else up to the builder in Experimental category. It has seen them ward off several predatory claims for owner or builder errors/faults. When you visit VANS, you will be amazed at how such a small 'factory' has been able to create some 10,000+ kits so successfully.

 

It occurs to me that many of the current LSA type manufacturers would be far better off by producing 'Quick-build kits' for the private/owner-builder market. Instead, they try to custom build aircraft,(in factory), for the flying school market where there is far more 'consumer liability' onus on them.

 

happy days,

 

 

[facthunter]

300 hours is not bad for a two stroke in a fairly loaded (most of the time) application like an aeroplane. 250 cc Japanese two strokes would do about 30,000 kms reliably in bikes and they are not loaded to the same extent. Roller bearings have a more finite life related to time and power delivered than plainbearing engines where clean oil is more important. A roller bearing fails due to fatigue of the surface of the hardened components and it decides to flake off. Not easily predicted and hard to check. A "playless" bearing may fail ten hours later. Cages fail also without warning and the results can be dramatic. Usually when you buy a new engine (582)n you get the carbs ,electric and exhaust system. Run 450 hours and sell it for something else unless your airstrip has good engine out escape routes around the airport. They are usually pretty reliable up to about that time. Don't let the fact someone else got supposedly 1,000 housr out of one tempt you if you have to clear a row of trees on every take off. Nev

 

 

[Soleair]

Or do as I did, & opt out of the Rotax stranglehold. I am very happy with the MZ 202 engine on my MiniMax. Larger displacement; more power, & lighter than the Rotax. Used on Mosquito helicopters, so good track record.

 

Compact Radial Engines

 

Bruce

 

 

[facthunter]

A Rotax two stroke is only a skidoo motor. They are nothing special. Just a suitable motor adapted for a plane with redrive options with a good/ acceptable power /weight ratio that mounts easily and the only remaining one Rotax produces is the 582. Nev

 

 

[onetrack]

There is not any automotive engine in any car that ever runs full throttle for five to ten minutes every time it's run then often for full throttle a few more times during the use cycle then at a cruise of 75% or so

Jaba - It's pretty obvious then - you haven't watched any hire cars, or cars owned by P-platers, in action!!A mate said to me once - "You know, there's only two types of cars that will pass you on the highway - regardless of whatever ballistic speed you're travelling at!

 

Those two types of cars are - hire cars, and P-platers cars!!

 

 

[facthunter]

If you drive like an aero engine runs you won't get through many corners. Cement mixers used to go through Holden engines. nev

 

 

[onetrack]

Fair go, Nev. Cement agitators used to chew through Holden engines, because they lived in a tough, dusty construction environment - and they used cheap, standard Holden air cleaners, instead of heavy duty industrial air cleaners, such as Donaldson.

 

Those high-speed P-platers and high-speed hire cars always came to grief on corners.

 

A curve that's easy to negotiate at 90kmh, becomes a very sharp curve at 180kmh!

 

Wouldn't mind a dollar for every rolled hire car I saw, on the back of a tilt tray!

 

 

[M61A1]

300 hours is not bad for a two stroke in a fairly loaded (most of the time) application like an aeroplane. 250 cc Japanese two strokes would do about 30,000 kms reliably in bikes and they are not loaded to the same extent. Roller bearings have a more finite life related to time and power delivered than plainbearing engines where clean oil is more important. A roller bearing fails due to fatigue of the surface of the hardened components and it decides to flake off. Not easily predicted and hard to check. A "playless" bearing may fail ten hours later. Cages fail also without warning and the results can be dramatic. Usually when you buy a new engine (582)n you get the carbs ,electric and exhaust system. Run 450 hours and sell it for something else unless your airstrip has good engine out escape routes around the airport. They are usually pretty reliable up to about that time. Don't let the fact someone else got supposedly 1,000 housr out of one tempt you if you have to clear a row of trees on every take off. Nev

300 hours is very conservative. These engines routinely go over 600 hours, and often over 1000, if looked after and monitored. 300 hours is what the factory pretty much guarantees as a minimum life. I put it to you that if you are relying on that engine to keep you alive over trees, you're flying wrong. I find it astonishing in this severely risk averse nation, that there are pilots who expect that their one engine, whether it's a two stroke ,four stroke, turbine, Jab, Lyc, Conti or whatever, will never fail them inside TBO.

 

 

[facthunter]

You can't effectively monitor/check a roller (or ball) bearing. Play is not a good indicator of condition. I have explained above. You are not really doing people a favour by implying you can operate those engines to 1,000 hours. I know of one at a tech college that did that but fairly special circumstances prevailed there

 

300 is conservative true, that's why I said 450.. A new motor is a better proposition than any available rebuild for value for the average person. If you are fluent in two stroke crankshaft rebuilding then build one up but you still have old carbs ignition and exhaust

 

I've always said ANY engine can fail. The trees analogy could be houses or rocks. IF you have (as I said) a good escape route around the aerodrome fly any kind of motor properly and it can't hurt you. I'm prepared to fly some pretty weird stuff, but I pick my time and place. I like to fly safe(ly) and my "advice" is along those lines. Nev

 

 

[facthunter]

One T, It's not just the dust (which can ruin anything). On the road no matter how fast you drive you just don't (can't) maintain a constant high output without being booked or missing a corner. Compressors and generators and ships run at a high % of max rated. Your average car is loafing and will keep going even when it's condition has deteriorated quite substantially for years if you are lucky. Nev

 

 

[Yenn]

Those two stroke engines can fail at any time with very little warning. A friend had a two stroke Rotax and landed on an island beach with others. When it was time to leave, he couldn't start so we fiddled around and eventually he got going. He flew to the next island which was where he lived and we all breathed a sigh of relief. A few days later I saw him, with the engine in his truck. The little end caged bearing had collapsed and the head looked as if someone had hammered it with a scutch hammer, the rest of the engine was well battered where the rollers had gone through the port into the crankcase. Motor a complete write off. the amazing thing was that when we got him going on the beach, the motor sounded sweet.

 

 

[kasper]

Those two stroke engines can fail at any time with very little warning. A friend had a two stroke Rotax and landed on an island beach with others. When it was time to leave, he couldn't start so we fiddled around and eventually he got going. He flew to the next island which was where he lived and we all breathed a sigh of relief. A few days later I saw him, with the engine in his truck. The little end caged bearing had collapsed and the head looked as if someone had hammered it with a scutch hammer, the rest of the engine was well battered where the rollers had gone through the port into the crankcase. Motor a complete write off. the amazing thing was that when we got him going on the beach, the motor sounded sweet.

And if that was a rotax it wax either a very long time ago or an ancient engine - cages were replaced with cageless on the little ends in the early 1990's ...

 

 

[Soleair]

Those two stroke engines can fail at any time with very little warning.

To be fair, Yenn, ANY engine can fail at any time with very little warning. Of course, certificated engines are more reliable, but even these can - and do - fail: witness the American Airlines engine bursting into flames on takeoff on the news this evening.

 

Personally, I fly with one eye on an emergency landing field at all times, & I'm not brave enough to fly over tiger country in my plane. 'Even' in the Jab I occasionally fly, I feel distinctly uncomfortable over the ranges.

 

But then, if flying wasn't exciting, I wouldn't do it. And my wife would be a happier bunny, & I'd have more money in the bank. . .

 

Bruce

 

 

[rollerball]

300 hours for a 582 is VERY conservative. Yup, we can and do fly them 'on condition' here in the UK, as we do also the Rotax 4-strokes, but a clued-up owner monitors the bearing wear with a dial gauge and occasionally has a look through the exhaust ports to see if anything looks amiss. If you do that and fly it conservatively, it's unlikely that the engine will let you down. As we say over here, print in pilot hand books and frequently placard even when brand new, 'this aircraft is not certified for any public purpose and pilots should assume that the engine can stop at any moment' (or words to that effect).

 

You lot certainly seem to have become very browbeaten down under - even worse than in the UK and that's saying something. Mind you, I now live and fly in the real land of the (flying) free, France, where they say 'you and you alone are responsible for the airworthiness and safe operation of your aircraft' and then let you get on with it. That's how it should be in a grown-up world

 

 

[facthunter]

A clued up owner would know enough to not trust a roller bearing condition with a dial gauge measurement of wear.. Ball and roller bearings don't "wear" in the normal sense.. They fail due fatigue of the hardened surface or cage failure, neither of which will be picked up by the test you rely on till it's failed. When you design something that has antifriction bearings in it you rely on bearing maker's life figures for load and revs used . They are the main factors. Rotax aren't stupid. IF they could promise higher figures they would. It's an aeroplane not a lawnmower or snowmobile. Nev

 

 

[onetrack]

The advantage of a roller bearing is that it gives warning of impending failure, by flakes of metal coming off the rollers or race surfaces. They rarely fail rapidly.

 

A plain bearing, such as those used normally in most IC engines, can and will, seize up rapidly when it fails.