David,

 

You're welcome to drop in to Lockhart, TX any time and take a look at my p-port 3-rotor Lancair ES.  It reliably produces loads of horsepower, while cruising at over 200 mph on about 11.5 gph.  And yes, it is loud.  Any "quiet" mufflers I've tried have increased EGT's while reducing top speed, or didn't last long enough to find out how well it worked.  I'm still running a "DNA" muffler (made in Canada). 

 

Mark S.

On Thu, Dec 11, 2014 at 9:17 AM, David Leonard <flyrotary@lancaironline.net> wrote:

In a perfect world I would have a turbo p-port 3-rotor. :-)

I sort of ended up with a turbo because it was just sitting there (came with my '91 turbo engine) so I decided to try it on for size and it never went away.  I am glad I have it, but the 3-rotor and/or p-port would have been nice options.  The turbo quiets things down just enough to be tolerable, but my formation friends can hear me when I am flying on their wing...  largely because the sound is different, but it is also a little louder I think.  But is is quieter than a n/a rotary engine by just enough to matter.

The turbo is not particularly less expensive than a p-port in the long run.  By the time I got most of the issues worked out I am in for over $5k in turbo rebuilds and non-fitting manifolds etc.  Even when cared for correctly (keeping EGT down), they are only going to last 1000 hrs or so (who knows) and each rebuild costs $1k.  In the long run though, these costs or the costs of a p-port or 3-rotor are trivial when compared with the cost of operating an aircraft.  If my turbo has cost me $5/hr, then Avionics have cost $20/hr, gas has been $45/hr and the hangar has been about $50/hr.  Dont let the relatively small cost differences sway your decision here.

The turbo definitely adds much more power than p-port would, both down low and up high.  And with the p-port the sound issue is not trivial if your are going to be maximizing the power output. Lets put it this way, you wont find me ever removing my turbo.

But, if I were to do it again, I would probably go with a 3-rotor.  Pretty close to the same power as the turbo, weighs a little more but is more reliable and efficient.  There have been many examples of successfully (and continued) flying of turbos and 3-rotors.  But p-ports in aircraft are sort of like UFOs:  you hear a lot about them, but you never really see one.

Not to say that p-port isn't the best option.  It is light weight, simple (in a sense), reliable, efficient, lower drag, and brings the power of a 2-rotor right where you need it for something like an RV.

I hope this discussion has be helpful (yea right!).

Dave Leonard

On Wed, Dec 10, 2014 at 3:12 PM, Neil Unger <flyrotary@lancaironline.net> wrote:

Dave,

            A few of us in OZ were discussing your engine with full authority (Called ignorance) and wondered what engine you have and what your thoughts are re the turbo.  Is it worth the effort??  Just looking to save the P port cost, and get a slight HP boost, with the muffler problem eliminated.  Does it actually work that way, or is it too much grief?  Neil.

 

From: David Leonard

Sent: Thursday, December 11, 2014 8:04 AM

To: Rotary motors in aircraft

Subject: [FlyRotary] Re: smoke system control, was: Re: [FlyRotary] Re: the List

 

everyone agrees that although the sound of my rotary is a cry for attention, It does make the best smoke of the group.

 

Here is a picture of the pump placement

 

David Leonard

 

On Wed, Dec 10, 2014 at 10:38 AM, David Leonard <flyrotary@lancaironline.net> wrote:

I have smoke on my plane, I just used the same pump as the EFI pump that Tracy used to sell.  it weighs less than a pound and puts out about the right flow rate.  Built in check valve.  I have not problem with leaking. instant cutoff.  Tank is in the wing and pump in the wing root which keeps the system and oil smell out of the baggage area.

 

The rotary makes nice hot exhaust which is great for supporting a lot of oil without leaving a residue (except for the 2-stroke oil)

 

Dave Leonard

 

On Sat, Dec 6, 2014 at 6:05 PM, Charlie England <flyrotary@lancaironline.net> wrote:

http://www.vansaircraft.com/cgi-bin/store.cgi?ident=1417917551-356-672&action=search

This is made to control fuel to primer ports on a carb'd engine, but would probably do the job. No idea how well it would survive the heat of the engine compartment, where it would need to be for a quick/clean cutoff. Maybe mounted low on the firewall away from the air exit, with the lines running uphill to the smoke port on the exhaust?

Charlie

On 12/6/2014 2:59 PM, hoursaway1 wrote:

Yep, I'm here in Michigan doing holiday stuff & visiting kids/grand kids.  also am working on a smoke sys. for the RV6A Rotary, want min. 3 gal., portable, useing automotive fuel pump, looking for a solinoid valve control for flow ( no dribbling soft smoke trail ).  David R. Cook

 

 

---

From: "Fly rotary blog, e-mail" mailto:flyrotary@lancaironline.net
To: "Fly rotary blog, e-mail" mailto:flyrotary@lancaironline.net
Sent: Friday, December 5, 2014 10:10:54 PM
Subject: [FlyRotary] Re: the List

 

The last message that I seem to have received from the list was 11/19. this
is a test to see if I have inadvertently been dropped.
Bill Schertz