Engine Choice Jab' vs Rotax

[turboplanner]

I've gone more macro in recent years and use Jetstar etc for the longer legs, then hire, so the cost comes down again on the long trips.

 

In the US I hire with an instructor so there are no radio/nav/local experience issues.

 

 

[JohnC]

Hi Rick,

 

Had exactly the same problem, I am building a Europa and can use the Jab 3300 or Rotax 9 series, have decided on a Rotax 912ULS.

 

Statistics and figures can be distorted and it’s generally accepted most Rotax failures are the two strokes not the 912 series, however fail to maintain or install or set-up any engine properly and diligently IT WILL fail regardless of make.

 

I have been on both the Jabiru and Rotax engine courses and certified to work on both, and like them both. I have flown circa 400 hours on the Jab 3300 and it’s a super smooth powerful engine, however had 2 failures and a forced landing – flywheel bolts and ignition coils/system failure.

 

I have a few hours on a Rotax and don’t really like the “busy buzz” sound of the Rotax compared to the “growl” of the Jab 6.

 

The Jabiru is very high maintenance compared to the Rotax although the Rotax is more complicated, maintenance costs will probably be similar as Jab parts are cheaper but Jab servicing is every 25 hours compared to Rotax every 100 hours when run only on mogas.

 

Jab engines have their weaknesses as you will probably have read about, however if installed, maintained, monitored and operated correctly they are pretty good. The Rotax is a better engineered engine from a manufacturer with many decades of experience and linked to BMW as a supplier, and the Rotax is now the engine of choice on many certified light aircraft, military drones and factory built micro-lights however the price of a Rotax is significantly higher than the Jab engine.

 

The Rotax will use at least 30% less fuel and was designed for mogas but only gives 100hp compared to Jabs 120hp unless you opt for Rotax 914 / 915 with turbos, fuel injection and lots of electronics however the cost is now bordering on the ridiculous and the engine is getting very complex.

 

I chose the Rotax 912 (100hp with carburettors) because reliability is my main requirement (I will fly 200+hrs/year and long distances if conditions allow), followed by low fuel consumption, low maintenance and no/minimal tinkering.

 

To summarise if you want a powerful engine “with a soul”, don’t mind high maintenance, tinkering and monitoring, don’t mind avgas (Jabs are happier on avgas), higher fuel burn and looking to fly 50-100 hours per year get a Jab.

 

If you want low maintenance, no tinkering / easy set-up, high reliability, low fuel burn on mogas, looking to fly high 200+ annual hours and don’t mind flying a bit of a soulless “busy bee” get a Rotax.

 

 

[JohnC]

Rick,

 

Forgot to mention 1 point - Jab are using new suppliers and methods for their new / revised engines so it must be considered that this "new" engine has not got any / much real world hours and there may be teething problems, you need to consider that you may be one of the first "guinea pigs".

 

 

[planesmaker]

Just on the cost of the 2, jabiru is not really cheaper when you factor in 1000 hr life compared to rotax 2000 which generally they have no problem attaining. Having talked to jabiru they say most operators put a new engine in at 1000 hrs

 

 

[Yenn]

I run a Jab engine and do the proper maintenance and it may be more often, but I take less time on maintenance than another operater here with a 912 Rotax. The Jab maintenance is little more than checking everything is still OK and its done.

 

I can't see the truth in saying RAAus is better for local and a Piper for trips away. Surely those plastic fantastics with glass cockpits are better than an aged Piper with years old technology. The Corbys are usually GA rego and I wouldn't consider them good for trips away.

 

 

[Narrabeenrick]

Hi Rick,Had exactly the same problem, I am building a Europa and can use the Jab 3300 or Rotax 9 series, have decided on a Rotax 912ULS.

 

Statistics and figures can be distorted and it’s generally accepted most Rotax failures are the two strokes not the 912 series, however fail to maintain or install or set-up any engine properly and diligently IT WILL fail regardless of make.

 

I have been on both the Jabiru and Rotax engine courses and certified to work on both, and like them both. I have flown circa 400 hours on the Jab 3300 and it’s a super smooth powerful engine, however had 2 failures and a forced landing – flywheel bolts and ignition coils/system failure.

 

I have a few hours on a Rotax and don’t really like the “busy buzz” sound of the Rotax compared to the “growl” of the Jab 6.

 

The Jabiru is very high maintenance compared to the Rotax although the Rotax is more complicated, maintenance costs will probably be similar as Jab parts are cheaper but Jab servicing is every 25 hours compared to Rotax every 100 hours when run only on mogas.

 

Jab engines have their weaknesses as you will probably have read about, however if installed, maintained, monitored and operated correctly they are pretty good. The Rotax is a better engineered engine from a manufacturer with many decades of experience and linked to BMW as a supplier, and the Rotax is now the engine of choice on many certified light aircraft, military drones and factory built micro-lights however the price of a Rotax is significantly higher than the Jab engine.

 

The Rotax will use at least 30% less fuel and was designed for mogas but only gives 100hp compared to Jabs 120hp unless you opt for Rotax 914 / 915 with turbos, fuel injection and lots of electronics however the cost is now bordering on the ridiculous and the engine is getting very complex.

 

I chose the Rotax 912 (100hp with carburettors) because reliability is my main requirement (I will fly 200+hrs/year and long distances if conditions allow), followed by low fuel consumption, low maintenance and no/minimal tinkering.

 

To summarise if you want a powerful engine “with a soul”, don’t mind high maintenance, tinkering and monitoring, don’t mind avgas (Jabs are happier on avgas), higher fuel burn and looking to fly 50-100 hours per year get a Jab.

 

If you want low maintenance, no tinkering / easy set-up, high reliability, low fuel burn on mogas, looking to fly high 200+ annual hours and don’t mind flying a bit of a soulless “busy bee” get a Rotax.

Thanks for that mate, Very informative for both engines.

Cheers

 

 

[turboplanner]

I can't see the truth in saying RAAus is better for local and a Piper for trips away. Surely those plastic fantastics with glass cockpits are better than an aged Piper with years old technology. The Corbys are usually GA rego and I wouldn't consider them good for trips away.

Depends on the glass; the toy crap I've flown would be luck to point you to the ground.

 

I agree that if you're going to do some serious touring you wouldn't use the GA training area, and most people quickly slide up the scale to the faster aircraft, CS, retracts as quickly as they can get endorsements.

 

Just the TSO'd instruments and radios alone would be worth more than the Starlet.

 

 

[Yenn]

Trying to sell the Starlet, anything seems to be worth more .

 

I need to find a buyer about 1.75m tall max, 70kg. Tailwheel conversant to the point of being able to jump into a single seater and fly it OK.

 

Gave up trying to sell 3 years ago.

 

 

[market]

G,day, I have flown approx.600 hrs behind a Jabiru 2200 motor, and about 30 behind the 3300. They are the nicest to listen to, very sedate and peaceful. If you look after them as per requirements, I don't think you have much to worry about.

 

I own and maintain a jabiru with a 100 Hp Rotax, which I upgraded to for extra lift capability, I have another Jabiru with a 2200 motor, and another aircraft with a Continental 470. Everything gets the oil changed at 25 hrs, especially if running on Av Gas. All three run best on unleaded fuel, the 470 likes 91 octane, the Jabiru and Rotax require 95. My Jab motors carbon heads every 180 to 200 hrs when run on Av Gas. I have documented every hour, fuel and oil added, Etc, unfolding trends are easier to pick up this way. Fuel usage is 16 ltr per hour at 2850 RPM in the 80 Hp Jab, 18 ltr per hour at 5400 RPM in the same aircraft with the 100 Hp Rotax, The extra performance is cheap. The Jab motor is very simple, and it it continually evolving for the better. That said, the first Jab motor I flew had 345 hrs on it and had been well looked after, I took it to over 600, it's still in operation and is getting close to 900 hrs on it, and it is a 2008 build. We live and fly these motors in the north of Aust with runway temps in the high 30's. I do not have cooling issues on either the Jab motors or the Rotax, it has everything to do with how you operate them.

 

The Rotax is definitely easier to maintain over the 2000 hrs, and I believe it will be the cheapest over that period. I know of 2 mustering aircraft that are approaching 3000 hrs and still don't use any more oil than they did from day 1, leak down test exceptionally well, but operated well and 25 hr oil changes. The 100 Hp Rotax motor certainly developers good power, the Jab 160D with that engine gets airborne so quick, climbs at rediculous ( wonderful ) rates, it added 20 kg over the 2200, but I think it's similar in weight to the 3300 motor. Jabiru engine is cheaper to purchase. Both Flood Imports and Jabiru give great back up service.

 

Hope this helps.

 

 

[Frankus1aust]

If you put the new Jab 6 cylinder engine in it you would get great performance. TBO if you do the maintenance is 1,000 hours. The local flying school has 3 x J160 and they LAME maintain them per schedule (2.2L engines) and replace the engines at 1,000 hrs. in 18,000 hours they have had one failure. On par with their Lycoming powered warriors.

 

 

[XAIRVTW]

Yeah thanks for your reply.They give you a choice of

Jabiru 3300

 

Continental O-200

 

Corvair

 

Lycoming

 

Rotax

 

CofG not sure

 

They recommend 100hp to 130hp

 

I plan on touring

 

MOGAS (95 RON)

 

and lastly not sure .

 

Like I said I'm open to either as well as the UL power ! and thoughts on that engine as well ?

 

Cheers

 

Rick

Out of all those choices if you can afford it the Lycoming!

 

 

[market]

Frank, I did investigate putting in a 3300, it's longer than the Rotax, I would have had to get new top and bottom cowls manufactured and would have had balance issues, due, not so much from the extra weight, but mainly from the extra length of the 3300 motor. The Rotax fitted into the existing space, with no balance issues.

 

As long as an engine consistently turns good fuel into the energy I require, I don't really mind who made it, be it Lycoming, Continental, Rotax or Jabiru.

 

 

[skippydiesel]

If this is what you are planning to do you are better off going GA.RA is better for pottering around, just enjoying flying for an hour or two here and there, going to the odd breakfast in the local area, but when you seriously commit to touring, the GA aircraft have the endurance and reliability, much less downtime ferrying jerry cans from various towns, the ability to fly longer kegs faster, and so make use of larger airports with more facilities, and provide the option of IFR training so you can get the aircraft back home within a weekend.

While RA has a lower cost per hour, when you are flying an hour at a time, the figures come out differently when you are covering touring distances; the faster the aircraft the lower the hours for a given distance, and even within GA, if you are talking about regular touring, the optimum aircraft are up the range from the C172 abd Cherokee Warrior.

 

Also, when you break down the costs per person touring, the more seats, the lower the cost.

 

I did this spreadsheet comparison in 2013, and it more or less shows that if you just want to have a fly around the local area, a Gazelle is fine, but if you want to tour, the Cherokee 6 is a low cost aircraft per person.

 

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Edited by Moderator

There are a host of RAA registerable, Rotax 912 (100hp) powered, aircraft that will cruise happily at 120 + knots from 16-20L/Hr on 95-98 RON (Robin Austin's Soneri, 160 Knots @ 16 L/Hr)

 

Yep! If you can CONSISTENTLY fill those seats, GA can be fairly cost effective. However most 4 seaters are only good for two up on a long trip, most 6 seaters only good for 4. A GA aircraft is unlikely to be as cost effective as the number of seat available might suggest. Then there is the problem of filling even one or two of those available seats. In my experience it is impossible to maintain a consistent flow of willing (to contribute) passengers over more than a few years of cajoling friend and relo's.

 

In the 7 or so years I have converted RAA I have never wished for an additional passenger seat, have never had a refuelling problem (its called planning) and don't worry about the cost of a long flight even if I end up going solo.

 

 

[Narrabeenrick]

Just found this vid on YouTube started to watch it looks interesting, I'll watch the rest later , thought I'd put in up here and see if anyone else has seen it.

 

"Aircraft Engine Debate, Continental, UL Power, Rotax, Jabiru, Sun N Fun 2016 "

 

 

Cheers

 

Rick

 

 

[Lyndon]

I have no real expierance of either but this is my opinion. If your hands off buy a new rotax. Get it serviced. Run in on unleaded. Make sure it starts well to look after the sprag. It will more than likely last the 2000 hrs just about trouble free. If you hands on get a Jab.I'm sure they are both excellent and in my experience a well looked after engine generally tells you before it stops.

 

Lyndon