Eagler's Nest

Airframes => Double Seaters => Topic started by: Kiwi55 on March 06, 2017, 07:17:20 AM

Title: Engine choice - Cabin Eagle
Post by: Kiwi55 on March 06, 2017, 07:17:20 AM
I'm getting close to the point of having to make a decision on an engine for my Cabin Eagle.
I'm not going for a minimalist option, I want starter and electrical system.
I am considering the following:
1. Direct Drive VW, probably 2180 cc and probably from Great Planes (if they respond to me email).
     Pro's, that's what the CE was designed for, probably the cheapest option, much cheaper to overhaul. Con's, I'm not convinced that direct drive is the best option, may     be marginal with a full load.
2. Redrive VW, again probably 2180cc and from Great Planes
     Pro's, Better use of engine power, More prop options. Con's, More weight, more money
3. Rotax 912, would have to be a used/rebuilt engine
    Pro's, Lighter, better use of engine power. Con's Probably more expensive to buy, much more expensive to overhaul, may be difficult to find at a suitable price when I need it.
4. Aeromomentum AM13 (Suzuki engine converted to aircraft use)
    Pro's, weighs about the same as VW with redrive, more power, modern technology with fuel injection and FADEC, in the upright version costs $8995, all new. Con's, all new, upright version might be too tall, low profile version $10,995.
5. Others? Any recommendations?
Is it feasible to install a direct drive (pulley end) VW and later add a redrive?
Title: Re: Engine choice - Cabin Eagle
Post by: PropMan on March 06, 2017, 07:39:06 AM
How about A Radial? Less than 130lbs installed, 65 HP @ 2300 rpm, less than 9000.00. You would need extended gear for prop clearance, 70-72" dia prop
Title: Re: Engine choice - Cabin Eagle
Post by: Tom XL-7 on March 06, 2017, 08:35:00 AM
Would like to add a "con" to your list. 
Any re-drive: something else that fails.
  I know of an aircraft that had a re-drive issue in the first 10 hours of test flights. That was a lot of work and money to throw away. No one was hurt.
Just as why are most aircraft air cooled. You eliminate a water pump, hoses, clamps and a radiator or two.  
 
 The VW has an rpm on the upper range of direct drive props. I get why you want to throw a larger prop slower.  ( as well as clearance). It's not like you can crank the rpm up for more power without dealing with the heat issues. I think there were some late model buses that had water cooled heads. It just keeps getting heavier and more complex.
Tom XL-7
I have a 4A-084, Barn fresh!
and a line on a 1/2 VW, dual plugs, scat heads, cheap $2000, 40 hp lightly used by an old man who is no longer living.
That 3 VW Verner still looks awful nice.
Title: Re: Engine choice - Cabin Eagle
Post by: Kiwi55 on March 06, 2017, 11:25:39 AM
The Verner Scarlett 5VW at $8150 looks very interesting. Weight also looks great.
Anyone have real world experience with them?
...
Title: Re: Engine choice - Cabin Eagle
Post by: MrG on March 08, 2017, 01:32:54 AM
First choice is the VW i have 35 + hrs on this ( 2276cc 94 bore x 82 stroke 8.22:1 on Avgas) and it runs and starts so sweet - using a Bing 64 Carby and you need to at least run the Great Planes Crankshaft no matter who builds it. (sorry Aero Vee Suck) can't say any thing good about them -  CB performance ( CA ) does great deals for part if you need to and what we use here in Australia ( Through Rod Penrose Racing )

it works with Frank's Prop ( o i love that prop ) and if engine assembled properly and serviced will run forever.
Mine is turn key with the Geni Pod to charge the battery ( http://www.ntin.net/jhardy/GenniPod.html Jim Hardie ) as long as you do longer than 25 minute flights it will stay
charged. 100% worth it

2 Choice
i had the chance 12 months ago why in texas to visit Frank and see the 3 cyl radial - If i had the money i would very closely have a look at the bigger radial
http://www.vernermotor.com/5SI.html  i dont know how W/B will go with the 5  - i did think Frank may of said the 3 cyl may develop enough torque for the DE ???

3rd 
Rotax is lighter than the Verner but $$$ "Its a great package" if you wanted a 25 thousand dollar CE/DE ( but its a great choice if i had the money i would of done this)
flow behind one for many hrs

I develope more HP than the 2180 in my DE and glad i did,   3150 rpm  i'm around 64 knots & climbs on a cool day @ 800 fpm (it gets some good comments)- Would not swap it for less HP
we run the bing 64 carby and spent may hrs tuning it to make it work and they are in my opinion are "the best choice" my neighbour has a OneX he tried there carby/slide bar
then swapped to the Aussie made TBH copy by Rotec, then after flying the DE walked inside and rang the distributor for Bing here and ordered one to put a Bing on his OneX
and loves it too

Last Rant
No i would not use a redrive  the aerodynamics don't work with the thrust line and prop size and on and on - personally the plane at 60/65 knts is near its limit for the design
the lines don't match speed and to spend money to go faster there's better places to gain than add HP due to the maths of drag - im waiting the out come of the redo of the
fuse of rfeenstra's mods -  http://www.eaglersnest.com/forum/index.php?topic=1340.0 (http://www.eaglersnest.com/forum/index.php?topic=1340.0) to see what he if or what gains - cheaper to re do the fuse that pay for HP and fuel
Just my AUD 3 cents (USD $0.02)
It runs just as good on 95 Oct Car fuel,  can't see any difference
Title: Re: Engine choice - Cabin Eagle
Post by: Kiwi55 on March 08, 2017, 05:53:06 AM
MrG,
I appreciate the information, most helpful.
How does the VW perform at gross weight? Can you comfortably carry a full size passenger?
Also could I get the spec's of the propeller you are using?

...
Title: Re: Engine choice - Cabin Eagle
Post by: Tom H on March 09, 2017, 05:41:44 AM
Kiwi, this may help answer your questions:

http://www.eaglersnest.com/forum/index.php?topic=1335.0

It is a summary of load carrying testing of DE Stubby.
Title: Re: Engine choice - Cabin Eagle
Post by: Kiwi55 on March 10, 2017, 05:45:01 AM
Thanks Tom that does help, but it also leave me a bit worried.
My Cabin Eagle is likely heavier and draggier than your DE.
It sounds like climb would be very marginal at max weight of 1050lb.
...Paul
Title: Re: Engine choice - Cabin Eagle
Post by: Kiwi55 on March 10, 2017, 05:52:49 AM
I have confirmed with Great Planes and Valley Engineering that if I installed a direct drive 2180 VW engine with force one hub (driving off front of engine), I could still install one of Valley Engineering reduction drives.
That at least gives me some flexibility if performance is not adequate with the direct drive.
I'm also still considering the AEROMOMENTUM AM13 option...
Title: Re: Engine choice - Cabin Eagle
Post by: Dave Stroud on March 10, 2017, 07:19:16 AM
A few years back I had a chance to fly with Roger Enns in his Dragonfly. It had a very nice EA81 Subaru engine with no redrive but it did have a small turbo. What a simple system that worked very well. He'd taxi with the waste gate open ( no turbo action ) , take off and climb full power with the turbo, then back off the turbo for cruise. It worked perfectly. His prop must have been very carefully selected.
Title: Re: Engine choice - Cabin Eagle
Post by: libertyman777 on March 14, 2017, 07:15:44 AM
Have you looked at this redrive?

http://www.airdromeaeroplanes.com/reductiondrive.html

I've wondered about using a redrive as well but for better short field performance.    But I'm guess the motor mount must be altered to account for the differences in thrust line. 

Title: Re: Engine choice - Cabin Eagle
Post by: Tom XL-7 on March 15, 2017, 07:06:14 AM
I have now. It is probably as good as any other. Maybe better. These guys have little choice with their giant cowls. A normal prop would look silly and probably be of little use other than an engine cooling fan. I once built a scale Thomas Morse Scout that I powered with a .020 cox engine. Looked pretty stupid. Would have been better off with rubber power. 
   A man not far from where I grew up designed a little plane called the  Stewart Headwind. It was powered by a VW. He developed and patented a reduction called "the maximizer". Most current redrives are based on this patent. The point being this has been going on around 50 years and can work out.
 The props mentioned in your link were 7 and 8 footers. That's a bit much for clearance -even more so if you adjust for thrust line. 
 The concept of using the VW is simple, reliable, and inexpensive. 
When you get to that point ask yourself what you're gaining. It will come down to what prop you can throw. Then you can see if it is worth it. 
For those guys who just have to have a redrive, Don Stewart did develop one for the 1/2 VW. I can find no info on it.
 Tom XL-7
Title: Re: Engine choice - Cabin Eagle
Post by: Tom XL-7 on March 15, 2017, 08:00:53 AM
I shouldn't bait you guys about the 1/2 VW with redrive.
I can find no info on it because it probably did not work out.
I think the power pulses are just too nasty to handle.

There is a builder who adjusted his thrust line lower for his half VW.
He wanted no doubt that when the throttle was opened up, the tendency would be to climb.
Imagine that.
Beats the alternative.
Tom XL-7
Title: Re: Engine choice - Cabin Eagle
Post by: cluttonfred on March 16, 2017, 08:46:46 AM
Have you considered contacting Scott Casler over at Hummel Engines?  He'll build the engine for you cheaper than Revmaster, in fact, cheaper than Great Plains or Aerovee will sell you a kit.  See https://www.hummelengines.com/

You might also consider the Davis Unified Igntion, basically GM HEI components in an integrated system, for your primary  (single?) or secondary ignition.  They custom tune the advance to your stated RPM needs and you only connect one wire to the unit for power and then the wires to the plugs, coil is inside.  It's a little wider and shorter than a Vertex magneto, so not terribly aerodynamic, but has a great reputation in automotive use.  See http://performancedistributors.com/product/vw-type-1-dui-distributor/
Title: Re: Engine choice - Cabin Eagle
Post by: Kiwi55 on March 16, 2017, 10:56:20 AM
Thanks I'll check them out as well.
...Paul
Title: Re: Engine choice - Cabin Eagle
Post by: MrG on May 10, 2017, 04:06:57 AM
@Kiwi55

sorry have not answered back to an earlier question to much fun flying
MrG,
I appreciate the information, most helpful.
How does the VW perform at gross weight? Can you comfortably carry a full size passenger?
At 1050lb it does it hard 200/250 fpm climb, i don't have full size wings about 1 ft shorter over all, also from my home work with the vee
at the top of wing attach you loose a bit of lift to - if widened to like a half cab or cable eagle you would gain there too , we widened the
windscreen at the top to 10in wider,   5 each side and plane was lets say did not like it - lost a lot of lift - if i did another fuse would def be like
a cable eagle (more like the cub/kitfox ) really waiting to see what  rfeenstra is doing when he test flies - from home work ive done with a smart
mate, thats the way to go, could see 70 knt cruise


Also could I get the spec's of the propeller you are using?
Yes 72x24 i think or 68x24 but ask Frank would not change a thing, i beleive its the same as TomH too, it really works at 3180 to 3200rpm im indicating 65knts
i have seen 800 fpm cold day, one up 35 litres of fuel, i believe im running 80hp
Title: Re: Engine choice - Cabin Eagle
Post by: Tom H on May 10, 2017, 05:59:36 AM
DE Stubby has a Great Plains 2180 engine w/ Performance Propeller 62 x 26 prop. 

For performance, see the link I included in my earlier post in this thread.

My advice to anyone building a DE - keep the weight to a minimum.  This is intended to be a bare-bones airplane.  Adding extra "goodies" like we did just takes away payload carrying ability.  But, at the other extreme, I don't know if anyone has ever built a DE as light as the prototype is reported to be (or even comes close!).

Another thought on climb improvement:  We have a LEU (Treehugger) that is being restored.  I wanted to put in a center section, which would increase wingspan by about 20-24".  I think this would improve lift.  But, the decision is to leave the wing attach alone, keep wingspan the same (mainly because it will have the new Verner 3 cyl engine).  I wonder if the DE Cabin types have a longer wingspan and if it helps climb and/or load lifting ability?
Title: Re: Engine choice - Cabin Eagle
Post by: PropMan on May 10, 2017, 06:58:48 AM
A Verner 5VW would be perfect on the DE or CE.

65 HP @ 2300 rpm
120 lbs ( installed weight should be 135 lbs with prop)
starter
electronic ignition
8200.00 plus shipping and import fees
Title: Re: Engine choice - Cabin Eagle
Post by: MrG on May 11, 2017, 03:32:43 PM
Sorry i thought my prop was bigger i have same size prop as TomH,  (Frank nailed the prop - Awesome)

@Tom with what i have played with i truly recon you would 100% gain lift buy making it a cabin, as you get to much disturbed airflow under the wings
 in the foot either side of the wing attach, and proved it in flight testing, found a photo of new screen when fitting , the plane was flown with this screen 
in and removed after flight - just making the top wider by 4 in each side made the plane nearly unflyable - top speed was 50 knts - old screen 65 knts

Even the nose were the screen its on the standard DE wing (under instead of over) would be causing so much drag, if you put your hand up there in flight 
on one side it yaws the plane by covering about 4in square from attach point between wing and top of screen. 

As Tom said add weight it slows down - I fly the plane with my daughter @950lb with mate next door we at @1050 - The difference between me empty
and daughter and slightly noticeable, but add that extra to get up around 1050, its like a 150 cessna on a 110 deg day
Title: Re: Engine choice - Cabin Eagle
Post by: ToddK on July 12, 2017, 07:21:58 AM
Yamaha Genesis 4 with PSRU.  These are being used on Kolbs and Gyros.

Check out Mohawk Aero Craft.
There are some pretty good youtube videos. 


https://www.youtube.com/watch?v=r8UXxcV1CFQ
Title: Re: Engine choice - Cabin Eagle
Post by: MrG on July 27, 2017, 05:13:55 AM
If you google that engine it really gets interesting
Title: Re: Engine choice - Cabin Eagle
Post by: wojtekseta on September 11, 2017, 12:38:11 AM
If you didn't made decision yet:
The best from mentioned earlier engines is Rotax, but if you don't have / dont't want to spend a lot of money, you should look at 100HP BMW boxer with TakeOff redrive http://www.takeoff-ul.de/ . From their site: BOXER-flat engine  R  1,2  GS 75  kW+  at 7200  1/min,  including  directly  programmable  electronic fuel injection, starter, three-phase current alternator, twin ignition, oil cooler - 58 kg. Ready to fly with exhaust, engine mount, fuel pump, propeller, etc should weight about 80 kg - 178 lbs.
They sold hundreds, maybe more of the powerplants.
The engine is powerfull, smooth working, silent, economic. Will lasts for thousends of flying hours. In the USA was sold a lot bikes with this family of engines - you will have no problems with service and spare parts.
Title: Re: Engine choice - Cabin Eagle
Post by: scottiniowa on September 11, 2017, 04:32:44 AM
Quote from: wojtekseta on September 11, 2017, 12:38:11 AM
If you didn't made decision yet:
The best from mentioned earlier engines is Rotax, but if you don't have / dont't want to spend a lot of money, you should look at 100HP BMW boxer with TakeOff redrive http://www.takeoff-ul.de/ . 
any chance you have a link to a english version, or is there a simple tab for english?
Title: Re: Engine choice - Cabin Eagle
Post by: wojtekseta on September 11, 2017, 05:36:37 AM
Only few words and description of the options in English. You should look at tab "Produkte".
I have some old meterials in English, I can put them to download section.
Title: Re: Engine choice - Cabin Eagle
Post by: pramer on August 22, 2018, 05:12:50 PM
I am a fan of the suzuki G13bb I have heard lots of good reports about them.  The only negative things you will hear about this engine is from people trying to make it better or using a inferior reduction unit.  Belt reduction unit are a good thing to stay away from 2 things belts lose more power than a geared reduction and then lots of stories of belts coming apart.  The trike community has been using this engine for many thousands of hours.  Mounted upright as stock as you can go they are bullet proof. Here is a vendor with a wealth of knowledge http://airtrikes.net/engines.shtml (http://airtrikes.net/engines.shtml) sells gear reductions and instructions on how to do your own or ready to go engines.  I purchased an engine to convert but not done yet.  MIne cost $1000 including shipping to my door all accesories including starter alternator.  Dry weight converted about 180#  100 honest horsepower.  to zero time this engine rebuilt long blocks are about 1800$.  AeroMomentum looks beautiful but they are modding the engine alot and lack a long track record.  The engine will stick above the firewall about 8 inches in the center,  you could build the firewall taller.  compared to the early Peitenpol with the ford model A engine and a radiator to look through this is nothing.  You would still have good forward view compared to a cub.
Title: Re: Engine choice - Cabin Eagle
Post by: ParQld on August 23, 2018, 10:08:57 PM
Quote from: PropMan on May 10, 2017, 06:58:48 AM
A Verner 5VW would be perfect on the DE or CE.

65 HP @ 2300 rpm
120 lbs ( installed weight should be 135 lbs with prop)
starter
electronic ignition
8200.00 plus shipping and import fees



Hey Frank is that 8200.00 USD or EUR ?

cheers Paul
Title: Re: Engine choice - Cabin Eagle
Post by: cluttonfred on August 26, 2018, 06:46:06 AM
Scott at Scalebirds.com is a dealer for Verner radial engines in the USA:  http://scalebirds.com/about-1  The 68 hp 5VW goes for $9,960 including a Walbro WB-37 carburetor, alternator, electric starter, ignition coils and cables plus an additional $960 for dual ignition.  I think it would suit a Double Eagle or Cabin Eagle very well, but the cost would be quite a bit more than something like a Hummel VW.
Title: Re: Engine choice - Cabin Eagle
Post by: scottiniowa on August 26, 2018, 02:21:57 PM
Quote from: cluttonfred on August 26, 2018, 06:46:06 AM
 The 68 hp 5VW goes for $9,960 including a Walbro WB-37 carburetor, alternator, electric starter, ignition coils and cables plus an additional $960 for dual ignition.  
Quote from: PropMan on May 10, 2017, 06:58:48 AM (https://www.eaglersnest.com/forum/index.php?topic=1499.msg8691#msg8691)
Quote
A Verner 5VW would be perfect on the DE or CE.

65 HP @ 2300 rpm
120 lbs ( installed weight should be 135 lbs with prop)
starter
electronic ignition
8200.00 plus shipping and import fees
21% difference give or take,    in prices-  Hope it not the same set up for the two different prices.
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