REFLECTOR: engine choice

Wed Mar 14 11:05:17 CDT 2007

"As smooth as an eight cylinder."
-------------------------------------------------
I'd been an enthusiastic Deltahawk proponent for years, until I talked with 
Ken Mishler at the Velocity symposium last year. He helped install a 
Deltahawk at the Velocity factory and actually flew it a little. First of 
all, let me say that Ken likes it. He thinks it will be a good engine after 
they get all of the bugs worked out of it. They were having a problem with 
the oil temperature getting so hot that it melted an internal component.

Ken said that when he first sat in the Velocity with the Deltahawk idling, 
the instrument panel shook so much that he couldn't read the instruments. It 
was rattling like a diesel. Now, once you got the rpms up, it smoothed out. 
(He also said that the low end torque was phenomenal. He couldn't believe 
how quick the Velocity got off the ground.)

Part of my attraction to the Deltahawk was my disgust with the Lycosaurus. 
But the kit engines today are bringing the air cooled, horizontally opposed 
aircraft engines into the 21st century. I'm leaning towards ECI's IOX-360 
with the cold air induction system and their mechanical fuel injection. Plus 
two P-mags. And I'm going to check out that self-lubricating cam shaft. I'm 
going to provide ram air for a little better service ceiling. I like the low 
weight and simplicity of the air cooled engine. And I'll probably save 3 
months of building time with the IOX-360 compared to the Deltahawk.

The downside is fuel expense.  Where the IOX-360 will burn 9 gph, the 
Deltahawk will burn maybe 7 gph. But considering my 100 hrs/yr of flying, it 
would take 15 years to break even on the $10k price difference between the 
two engines. Heck, I might be dead in 15 years.

Sorry for the long post. I'm really getting into this project.

Doug Holub

----- Original Message ----- 
From: "michalk" <michalk at awpi.com>
To: "Velocity Aircraft Owners and Builders list" <reflector at tvbf.org>
Sent: Wednesday, March 14, 2007 10:01 AM
Subject: Re: REFLECTOR: engine choice

If fuel consumption is king, then you will be hard pressed to find a
solution better than an aircraft engine.
The bigger the cylinder, the slower the RPM, the better the BSFC ...
generally speaking.  Note: generally.  Add electronic fuel injection,
electronic ignition, variable valve timing, etc., and you get even better.

Since you are new, I'll repeat some concerns that I have.  Now I do not
have any practical experience, only what I observe out in the wild.
I have a concern with very high power four cylinder four stroke engines.
   This is one power pulse every 180 degrees of crank rotation.  That is
one hell of a bang!  That 200-plus horsepower is concentrated into a
very short crank angle.  This is hard on props, and all sorts of things.

If you wanted the best, I would say go with a diesel.  Actually, you
have plenty of time to work this out, so a diesel may be an alternative
by the time you are ready.  BSFC is good, it's cheaper, no spark plugs
... all sorts of benefits, *plus* it's two stroke!  As smooth as an
eight cylinder.

If you go with a six cylinder four stroke at least your power pulses
begin to overlap.

If I were you, I would determine my flying profile.  Long business
trips?  Puddle jumping?  Short strips?  Long runways?  High altitude
airports?

Then determine what performance you need to meet your flying profile.
You may find all you need is a little help every now and then with a
couple of minutes of past redline power.  Perhaps it's a turbo.  Perhaps
it's nitrous.  I like small efficient designs.  A smaller swept volume
engine will generally get better BSFC than a larger engine at the same
horsepower.  Your IO360 at 100% WOT will get better mileage than a
throttled back IO540 at 60% power.  Notice I did not say at wide open
throttle.

I like those little VW bugs with turbo.  Get the nice little engine
sized for the majority of the driving it's going to do.  Now, add a
turbo to give it that zip it needs to get in and around traffic.  Size
your engine for good performance during cruise, or whatever type of
flying you are going to do.  Sizing an engine for racing is completely
different than sizing an engine for max economy.

Benedikt Harren wrote:
> Dear all,
>
> thx for the helpful input. I am just trying to gather as much info as I
> can. As for the rotarys fuel consumption seems to be quite high and with
> aviation fuel prices of $9,82 / Gal. or 6,38 / Gal for auto fuel I want
> to keep my fuel consumption to a minimum.
>
> As for the rest of the factors that have to be considered when flying
> n-reg experimentals in Germany:
>
> - fuel costs --> low fuel consumption desired
> - very hard to get insurance; no hull insurance available through
> european inssurance companies (certified engine might help)
> - short runways (2200'; which should be o.k. according to velocity 
> website)
> - good climb performance needed because of lots of bad weather
> - high altitude capability to fly above weather (15000'-20000')
>
> A turbocharged TSIO 360 might be able to meet the above criteria??
> Target cruise speed should be 200kts with CS prop. + with Klaus
> Saviers's plasma ignition performance should increase and fuel flow
> decrease especially when flying higher (12000') and using hard leaning
> methods? Hope to see 200kts with 11,5 Gal, T/O within 1800 @ gross
> standard day sea level.
>
> Has anybody any numbers or opinions on that? Anybody flying a TSIO360 
> SE-RG?
>
> thx for the input,
>
> Ben Harren
> ( Std RG Elite N888GF / just getting started)
>
> ------------------------------------------------------------------------
> *Von:* reflector-bounces at tvbf.org [mailto:reflector-bounces at tvbf.org]
> *Im Auftrag von *Al Gietzen
> *Gesendet:* Mittwoch, 14. März 2007 01:41
> *An:* 'Velocity Aircraft Owners and Builders list'
> *Betreff:* Re: REFLECTOR: engine choice
>
> Ben;
>
>
>
> IMO; from the standpoint of both size and weight, I would not recommend
> a V8 installation for a SE RG.  If you want to go ‘alternative engine’,
> and want the HP of an IO540; but in a package that is smaller than an
> IO360, and weighs significantly less than a 540 – then consider a
> 3-rotor rotary, Mazda 20B.  You can see my installation, and the dyno
> results of the engine on my website
> http://members.cox.net/alg3/airplane.htm.  I am very pleased with the
> performance and operation of this engine.  I only have 23 hours in the
> air, so the reliability of my installation is still an unknown, but I’d
> say there is little question of the robustness of the basic engine.
>
>
>
> The spar on the long wing (at the inboard end is something like  2”
> wider than the short wing.
>
>
>
> Speaking of low-cut keel, I wonder to what extent it reduces the
> structural strength of the bottom of the plane.  As one who experienced
> a gear-up landing a couple of months ago (yes; I’m trying to forget, but
> there it is), the strength of the keel down the middle really kept the
> damage to a minimum.  Had that failed and allowed the bottom to ‘cave
> in’ at all, it would have been a much larger repair job.  The other
> thing the saved it was the microglass hardpoints for the cylinders and
> the seats which served a skid pads.
>
> But, then; you should never have to plan for a gear-up, or gear collapse
> – right?
>
>
>
> Al (repaired and painted, waiting for a prop)
>
>
>
>
>
>
>
> *Subject:* REFLECTOR: engine choice
>
>
>
> Hi all,
>
>
>
> I emailed with scott b. today regarding tools for my shop (just getting
> started) and the dual yoke option (with low cut keel). I also asked him
> about engine choices and told him that I was thinking about going
> automotive (once I get to that point). I have looked at Bill Mulrooney's
> V-8 installation which looks very promising (good T/O & climb
> performance + low fuel consumption + lots of HP). I have a Standard RG
> Elite model and was wondering if the smaller wing will be able to take
> the load of the heavier engine installation (similar to an IO-540)?
> After all, the only difference between the long and the short wing seems
> to be the wing itself, since the main spar looks identical !? I also
> noticed that load factors, published on the velocity website for the
> XLs are smaller than the ones for the Stds, letting me belief that the
> wings are of similar strength? I was just wondering what the group's
> input was on this (V8 installation with gross weight increase to 2800).
>
>
>
> Anybody else flying or building a V8 velocity?
>
>
>
> Kind regards,
>
>
>
> Ben Harren
>
> ( Std RG Elite N888GF / just getting started)
>
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> To change your email address, visit 
> http://www.tvbf.org/mailman/listinfo/reflector
>
> Visit the gallery!  www.tvbf.org/gallery
> user:pw = tvbf:jamaicangoose
> Check new archives: www.tvbf.org/pipermail
> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html

_______________________________________________
To change your email address, visit 
http://www.tvbf.org/mailman/listinfo/reflector

Visit the gallery!  www.tvbf.org/gallery
user:pw = tvbf:jamaicangoose
Check new archives: www.tvbf.org/pipermail
Check old archives: http://www.tvbf.org/archives/velocity/maillist.html