Jump to content
  • Welcome to Recreational Flying!
    A compelling community experience for all aviators
    Intuitive, Social, Engaging...Registration is FREE.
    Register Log in
Sign in to follow this  
geoffreywh

D-Motor

Recommended Posts

I would question the claim of 18 litres/hour at 75% power, (which is about 96 HP, otherwise I'm not critical.

 

Regarding the injection v.s carb. Clearly this engine need highly regulated fuel distribution to run well and cleanly. IF you are worried about injection system failure, it would be extremely simple to have a manual low pressure "limp home" alternative system added on that might not idle well but would be fine at just under normal cruise output. Nev

 

 

Share this post


Link to post
Share on other sites
I would question the claim of 18 litres/hour at 75% power, (which is about 96 HP, otherwise I'm not critical.Regarding the injection v.s carb. Clearly this engine need highly regulated fuel distribution to run well and cleanly. IF you are worried about injection system failure, it would be extremely simple to have a manual low pressure "limp home" alternative system added on that might not idle well but would be fine at just under normal cruise output. Nev

IIRC it has double redundant fuel injection system too...(2 pumps, 2 rails, and 2 injectors per cyl)

 

 

Share this post


Link to post
Share on other sites

You would still need electrical power, and there is a high cost. A manual system could weigh literally ounces being just a low pressure injector in the inlet tract. Nev

 

 

Share this post


Link to post
Share on other sites

Quote "Clearly this engine needs highly regulated fuel distribution to run well and cleanly." ( Ref: needed?) I can't really find where this fact comes from other than it is a valid statement for all engines to run at peak efficiency. I'd agree with the 95hp at 75% though. Time will tell all............

 

 

Share this post


Link to post
Share on other sites

In it's own advertising stuff it used the injection feature as overcoming some/most of the shortcomings of previous SV designs such as heating, fuel economy and carbon formation. Nev

 

 

Share this post


Link to post
Share on other sites

One thing that is sure about D-Motor is the excellent level of service they give.

 

A guy at our club bought one of the early 4 cylinder engines, which produced 80hp. It ran beautifully and he really liked it.

 

It started first time every time using an 800g battery and he had about 50 hours trouble free flying with it.

 

However, that orignal design has now been superseded by the improved LF26.

 

Two days ago a guy from D-Motor drove down from Belgium (8 hours) with a replacement engine which he helped our guy install as a replacement on his Sherwood Ranger. The engine tests were completed yesterday and he now has the new version (93hp).

 

What did that cost our guy; nada, nothing, not a cent !

 

 

  • Like 4
  • Winner 2

Share this post


Link to post
Share on other sites

Here's a question will a dirty battery terminal,a tripped circuit breaker or a blown fuse stop this engine?

 

 

Share this post


Link to post
Share on other sites
One thing that is sure about D-Motor is the excellent level of service they give.A guy at our club bought one of the early 4 cylinder engines, which produced 80hp. It ran beautifully and he really liked it.

 

It started first time every time using an 800g battery and he had about 50 hours trouble free flying with it.

 

However, that orignal design has now been superseded by the improved LF26.

 

Two days ago a guy from D-Motor drove down from Belgium (8 hours) with a replacement engine which he helped our guy install as a replacement on his Sherwood Ranger. The engine tests were completed yesterday and he now has the new version (93hp).

 

What did that cost our guy; nada, nothing, not a cent !

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

 

 

Share this post


Link to post
Share on other sites

Ah, I see - that IS smart marketing - the customer is not saddled with any potential problems on the prototype, plus there are cost savings in not having to maintain a parts inventory for one engine.

 

Great service as you say!

 

 

Share this post


Link to post
Share on other sites

I must say that having spoken to the guy from the company, they certainly seem to be very serious about 'doing it right'.

 

Another example he gave me is that the ECU is fully programmable (I watched him setup the idle on the Sherwood Ranger using his PC plugged into the ECU) and you get the software with the engine to allow you to log data and monitor conditions.

 

If later you have a problem and you contact their telephone support service, and they determine that it requires modifying the ECU, they will give you an access code which is valid for 24hrs only to allow you to make the necessary changes, following their guidance.

 

.

 

1.jpg.02bd4143f5c74fbe1205218a96572f4a.jpg

 

 

Share this post


Link to post
Share on other sites

Quote "Here's a question will a dirty battery terminal,a tripped circuit breaker or a blown fuse stop this engine?" Good question..... I think you'll find that the Ign/Injection will have its own dedicated back up battery. The ECU will certainly have a " limp home mode" .With the weight of a LIFE04 battery these days I would expect at least 2 hours flight time after generator and main battery failure.... I don't think the ignition is self generating ala Rotax..........Which is a pity.

 

 

Share this post


Link to post
Share on other sites
Here's a question will a dirty battery terminal,a tripped circuit breaker or a blown fuse stop this engine?

The Achilles heel of all FI engines, the fuel pumps.

 

 

  • Agree 1

Share this post


Link to post
Share on other sites

two pumps each with its own power source. I don't think so. My crummy Mitsubishi has run now for 11 years with nary a miss....And don't give me any bull about 75% power. The pump doesn't care.. Although if they were direct injection pumps that might be another story. I fly around on two mags...Both 50 plus years old... I like the odds on the pumps lasting longer

 

 

Share this post


Link to post
Share on other sites

I think with the redundent EFI system it would be possible to run 2 totally independent systems with a backup power supply the modern jet liners have a drop down prop driven turbine that takes over flight necessary functions in the event of complete power failure.or as Geoff says a small secondary battery.

 

 

Share this post


Link to post
Share on other sites

The fuel pumps on your carburettor engine are only doing 2-4psi, the FI engines are typically @ 50PSI. The pumps chew a lot of power, much more than the ECU does. The other problem is the fuel lines, if they start leaking fuel comes out under a lot of pressure (instant fireball). Its a fair trade off as electronics and batteries these days are super reliable.

 

 

Share this post


Link to post
Share on other sites

I think I know the answer, but would rather be sure so I will ask these questions of the owner of the Sherwood Ranger when I see him at the weekend.

 

I'll get back to you.....

 

.

 

 

Share this post


Link to post
Share on other sites
The Achilles heel of all FI engines, the fuel pumps.

Here's a thought.

 

Which is more likely to occur, failure of two independant fuel pumps or carb icing ?

 

.

 

 

Share this post


Link to post
Share on other sites

Carb ice is not hard to handle, if you have an adequate system. The intake of any engine can be affected by icing even if only Rhyme (sp)? You have to have some kind of air filter (which could be bypassed). The main fault of a carburetter is uneven distribution of fuel mixture, in some engines.. Nev

 

 

  • Agree 1

Share this post


Link to post
Share on other sites
Carb ice is not hard to handle, if you have an adequate system. The intake of any engine can be affected by icing even if only Rhyme (sp)? You have to have some kind of air filter (which could be bypassed). The main fault of a carburetter is uneven distribution of fuel mixture, in some engines.. Nev

Usually spelt Rime apparently but a bit like other weird words like "girt" by sea

 

1. A coating of ice, as on grass and trees, formed when extremely cold water droplets freeze almost instantly on a cold surface.

 

 

Share this post


Link to post
Share on other sites
I think with the redundent EFI system it would be possible to run 2 totally independent systems with a backup power supply the modern jet liners have a drop down prop driven turbine that takes over flight necessary functions in the event of complete power failure.or as Geoff says a small secondary battery.

The specs on the engine show an integrated alternator, the whole system doesn't appear much different in concept to the average modern gas turbine. Meaning that while the engine is turning, it's generating it's own power to supply it's engine management. I don't really understand why the same people that will tell you a carburettor and magneto is more reliable, will happily get on something with a CFM-56 powering it, with all the FADEC stuff (not bagging CFM in any way). We're just moving into the 21st century, that's all.Note. While I can't speak for this lot, most aviation electronic engine management systems have double redundancy built (and a built in test) into the box itself, just because you can't see 2 boxes, doesn't mean there is no backup.

 

 

  • Agree 5

Share this post


Link to post
Share on other sites

001_smile.gif.2cb759f06c4678ed4757932a99c02fa0.gif

 

The specs on the engine show an integrated alternator, the whole system doesn't appear much different in concept to the average modern gas turbine. Meaning that while the engine is turning, it's generating it's own power to supply it's engine management. I don't really understand why the same people that will tell you a carburettor and magneto is more reliable, will happily get on something with a CFM-56 powering it, with all the FADEC stuff (not bagging CFM in any way). We're just moving into the 21st century, that's all.Note. While I can't speak for this lot, most aviation electronic engine management systems have double redundancy built (and a built in test) into the box itself, just because you can't see 2 boxes, doesn't mean there is no backup.

I agree otherwise we would all be still flying around in wright flyers .Thats why a lot of us are flying around in aircraft called experimental without people asking questions and exploring possibilities nothing changes.I think innovators like the guys that start from scratch and build new motors with cutting edge technology need to be encouraged .I asked if the engine would stop if a fuse blows or a battery terminal is loose or a circuit breaker drops out how have they solved these problems .

 

 

Share this post


Link to post
Share on other sites

The alternator on a jet engine does not usually supply it's own engine management . It's a main power supply for the entire aircraft electrical system. ( One of three, minimum) and can go faulty (over/undervolt, over /underspeed) and be disconnected in flight, with out affecting anything except electrical total load considerations. There are many electric subsystems that enable isolation for fault checking and limited operation with faullts, as well as a priority supply bus usually denoted "essential". The ultimate supply is from the batteries which is all you might have when you hop into the cockpit. You don't really have aircraft power of any significance, unless external supply available or the APU is running.

 

The type of alternators are AC and have strict limits on frequency so have special constant speed drives to keep frequency in the range required over a wide range of engine RPM. DC supply comes from battery or inverters. Nev

 

 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×
×
  • Create New...