D-Motor

[facthunter]

This touches on another aspect of failure causes. I have seen plenty of work carried out on Jabs under the 'direction' of so called experts which I would see as somewhat "suspect" in technique. Fiddling not done well will not enhance reliability nor will neglect but performing a service "wrong" has potential for serious consequences.

 

One of the reasons the Rotax gives good service is that most people leave the "core" engine alone. It's usually exhaust systems springs and cracks and carb mount rubbers that need attention, and these are relatively easy to address. The cooling system is a dog's breakfast but the engine can suffer leaks and still be landed with the engine running. Nev

 

 

[geoffreywh]

Back to the thread..................There is redundancy in the D - motor systems. Both ignition and the fuel injection. You would have to have a double pump failure or a double ignition and/or double battery failure to bring the aircraft down. Which is a better situation than I/we have now, So long as they don't start breaking through bolts? The fact is, that you are statistically, FAR more likely to run out of fuel than you are having a double pump or ignition failure. Modern systems.....Good on yer...

 

 

[fly_tornado]

Did you see with the 912IS that Rotax built 2 seperate alternators in the same housing?

 

 

[Gentreau]

.......The newer complex engines will be rectified by "remove and ship to service agent". for adjustments and repair, if we don't watch it. Nev

Or in the case of D-Motor, download the ECU logs and send them to the manufacturer, as a first course of action.

 

 

[facthunter]

Yes I can see that as a course of action, Gentreau. Often the only way in the past, is to change things from another motor till you find what is malfunctioning. Many modern systems self fault find and are modular. Just needs the right approach to the concept.

 

A motor in a plane is not operating in a complex environment with constant power changes like road transport so the Jabiru concept of simplicity is valid. I'm quite happy to operate with variable mixture, throttle and ignition timing, myself It's part of the fun and challenge. I like to "feel' the plane and fly and trim it , (on all 3 axis) . Some like to plug in the autopilot, which is fine on a long trip or if you want to do some amendments to your documentation.

 

The "D" motor and the Rotax have one thing in common going for them and that is liquid cooling. Anadvantage in some ways but an added complexity . I am not against the "D" motor at all. It should also have a small width (narrow cowl) and is direct drive and low revving isn't it.?Nev

 

 

[Gentreau]

........It should also have a small width (narrow cowl) and is direct drive and low revving isn't it.?Nev

54.5 cm wide including spark plugs. http://www.d-motor.eu/nl/dimensions-39.htm

 

Yes it's direct drive, max revs 3300.

 

The only limiting factor at the moment is the smaller range of compatible props for direct drive, but that will improve with time.

 

.

 

 

[Guest Bingo]

Hi guy's

 

Been following this thread from the start. This is my first post and question on this site to those that are smarter than me on propellers.

 

What would be the smallest diameter prop that I would most likely get away with on the LF26 @ 220nm torque.

 

The aircraft is a Searey (pusher engine setup) which has a slow 85kts cruise due to airframe drag. Prop diameter clearance is limited to 68".

 

Also considering another aircraft that will have even less prop clearance.

 

 

[xair1159]

With a nominal 80hp Jabiru 2200 the UK Xair Hawk used a 60 diam x 40 pitch narrow chord prop. It is believed that actual engine output was probably closer to 70 something hp, and across several aircraft, not just one.

 

Current testing on the D-Motor Hawk (92 hp typical on the dyno) shows optimum performance is given by a 58 or 60 diameter x 46 inch pitch. Strangely the best takeoff / climb / cruise mix is given by the smaller 58" diam prop, the reverse of common wisdom of "swing a big prop slowly". You can certainly fly out of 250M strips with a good margin and no worries.

 

The Jab maxes at 3300 and D-Motor at 3100, not a lot different. Comparing the same cruise band of say 2400-2600 between the two, the Jab would give 80kts at 2500, the D-Motor closer to 90kts with better fuel burn thanks to the EFI.

 

On their website there is now a D-Motor agent listed for Australia.

 

 

[bexrbetter]

Thanks for the first hand reports xair, hope it works out well for you.

 

So, even though the existing engine was fine, for no other reason than they wanted to, they gave him a new engine?

That's standard service for startup industries who want to be around long term.

 

 

[Guest Bingo]

Thanks for the first hand reports xair, hope it works out well for you.That's standard service for startup industries who want to be around long term.

Any updates on your engine development bexbetter? What horsepower and torque are you aiming for?

 

 

[eightyknots]

Any updates on your engine development bexbetter? What horsepower and torque are you aiming for?

See this thread for further information Bingo: http://www.recreationalflying.com/threads/a-new-oz-engine-on-the-way-posts-moved-from-icp-thread.63583/page-7#post-295459

 

 

[bexrbetter]

The engine tests were completed yesterday and he now has the new version (93hp).

Any updates on your engine development bexbetter? What horsepower and torque are you aiming for?

94hp.

 

 

[Gentreau]

Update from the D-Motor website. The first two engines are being shipped to Oz.

 

The 2 first engines for Australia will be shipped this week. One is sold to the customer and the other is sold to the D-motor dealer who will install it on a demo plane. For more info you can call our dealer for Australia

http://www.d-motor.eu/nl/update-18-june-2013-95.htm

 

 

[xair1159]

D-Motor #14 is up and running in an Xair Hawk (H, Hanuman) with around 5 hrs flown so far.

 

Definitely more power than the Jab 2200 it replaced, smooth and good T's & P's in some fairly warm weather for this end of the world. Installed weight of 60kg wet and ready to run, this was the first "production" installation and could be reduced by 1 or 2 kg with experience gained.

 

The Jab would just drive a 60x40 prop, this is currently using a 60x46. Fuel burn typically 10-13 L/h at sensible speeds, 22-23 L/h flat out, which is around 95 kts in the Hawk, but there is still a bit more to come with a slightly revised prop.

 

It also sounds great!

 

The 6 cylinder is running on the factory dyno with good results so far and apparently it sounds even better.

 

Nick

 

 

[Greg Spiers]

I had a price for the 92.5 HP 4 cyl given to me from the Aust distributor the other day at a tad over $20,000 which, I was told, is a revised price as it was $22,000. I might be wrong but I am sure that came ready to fit and run.

 

Greg

 

 

[ozbear]

At

 

I had a price for the 92.5 HP 4 cyl given to me from the Aust distributor the other day at a tad over $20,000 which, I was told, is a revised price as it was $22,000. I might be wrong but I am sure that came ready to fit and run.Greg

At that price I don't expect to be knocked down in the rush

[bexrbetter]

I had a price for the 92.5 HP 4 cyl given to me from the Aust distributor the other day at a tad over $20,000 which, Greg

Sounds correct at the current $ conversion (USD 17500).

 

 

[facthunter]

What's a 4 cyl jabiru cost these days.? Nev

 

 

[eightyknots]

I had a price for the 92.5 HP 4 cyl given to me from the Aust distributor the other day at a tad over $20,000 which, I was told, is a revised price as it was $22,000. I might be wrong but I am sure that came ready to fit and run.Greg

I wonder how that will compare with Bexrbetter's motor (still in development) when this comes on the market??? Bex's motor sounds really interesting.

 

 

[fly_tornado]

sexmotor is a long way from finished

 

 

[facthunter]

So no one knows what a jab 2200 costs? No silly answers please.

 

A few machining places I have worked with when I put them onto the sites for Jabiru and Rotec reckon the prices are quite surprisingly cheap. Perhaps the expectation of getting a special purpose built low volume production engine below 20k is unrealistic. Nev

 

 

[geoffreywh]

oooh that is expensive for a flathead 4 ! What is the 6 going to cost? six fourths of twenty large? ....I wont be buying one anytime soon. I would rather a 3300 Jab with all the foreign fruit on it...and some change...

 

 

[dazza 38]

So no one knows what a jab 2200 costs? No silly answers please.A few machining places I have worked with when I put them onto the sites for Jabiru and Rotec reckon the prices are quite surprisingly cheap. Perhaps the expectation of getting a special purpose built low volume production engine below 20k is unrealistic. Nev

I guess CAMIT and Jabiru can only answer that Nev. I think that since the basic engine has been around for nearly 15 years. I think that the development costs would have been absorbed over that amount of time.

 

 

[ozbear]

What's a 4 cyl jabiru cost these days.? Nev

Nev last time I checked the 2.2 jab engine was around 14,500k

 

 

[facthunter]

Thanks ozbear, Comment... the motor has had quite a few minor changes. It was unique (at the time) for being machined from billet metal as is the Rotec radial. Some cast items may/have found their way onto these motors. ALL the people I speak to are in the same line of business.( CNC machining of similar types of components) I don't think the price of either motor is excessive. You can't really achieve very low prices unless the volume allows the use of expensive dies for vaccuum diecasting of parts. There are other ways of producing castings but don't achieve a real control of quality , so require more inspection.

 

SOME air cooled aero engine alloy heads are FORGED . This is the ultimate, but you get what you pay for.Nev