Received-SPF: pass
 receiver=logan.com; client-ip=205.152.59.66; envelope-from=ceengland@bellsouth.net
Message-ID: <42BB2168.2050801@bellsouth.net>
Date: Thu, 23 Jun 2005 15:54:00 -0500
From: Charlie England <ceengland@bellsouth.net>
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax)
MIME-Version: 1.0
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Subject: Re: [FlyRotary] Re: PP debate  was  Re: Single PP HP?
References: <list-1010889@logan.com>
In-Reply-To: <list-1010889@logan.com>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit

For me, it's just not in the mix. I'm not IFR rated & life is a lot more 
complicated for planes like RV-x's up in the flight levels (meaning many 
more ways to die). I just don't fly enough cross country to justify the 
extra equipment, training, cooling requirements, etc. required to fly 
that high at that high a power level, safely. If I can make a little 
more than Lyc power on the same fuel burn at VFR altitudes I'll be happy.

Charlie

Jack Ford wrote:

>Another consideration, Charlie, might be the ability to produce 75% of 200
>horsepower at FL180 or 200, without a blower. You might then be at a very
>comfortable burn rate and a wonderful TAS.
>
>Additionally, you should have enough steam to get up there pretty quick.
>Might even be able to show Rusty how to get a 3000 FPM rate ;>)
>
>Jack Ford
>
>
>----- Original Message ----- 
>From: "Charlie England" <ceengland@bellsouth.net>
>To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
>Sent: Wednesday, June 22, 2005 8:10 PM
>Subject: [FlyRotary] Re: PP debate was Re: Single PP HP?
>
>
>  
>
>>Lehanover@aol.com wrote:
>>
>>    
>>
>>>In a message dated 6/22/2005 7:23:37 AM Pacific Daylight Time,
>>>13brv3@bellsouth.net writes:
>>>
>>>    While Lynn seems to love PP for racing, I'm not sure I've seen him
>>>    state that he thinks it's the best way to go for aircraft.  How
>>>    about it Lynn, for, or against PP for aircraft use?
>>>
>>>
>>>Either side port (Bridgeport) or Pport will work just fine for
>>>aircraft use.
>>>
>>> This is your lucky day. I have a tube frame with a first Gen body and
>>>a factory Pport engine. It has a Weaver Brothers external pressure
>>>pump, but the front iron is intact, so you could go back to the stock
>>>pump if you like. It has a trans but no rear end. Needs a Speedway or
>>>similar quickchange. A nice trailer is included.
>>>
>>>The Pport has shorter intake timing than the "J" Bridgeport engine. It
>>>idles much slower than the Bridgeport engine and has power a bit lower
>>>in the RPM range than the Bridgeport.
>>>It is not difficult to drive around the paddock with a tall first
>>>gear. The Bridgeport is a nasty mess to drive around, and has around 3
>>>HP until it get wound up a bit.The Pport is also still making power
>>>right through 10,000 RPM if that ever comes up. This is a 12-A Pport
>>>with about 300 HP at 10,000.
>>>
>>>The home built 13B Pport could be much better. It is just too easy to
>>>build. As I pointed out with the 12A data at 7,500 212 HP and that
>>>engine has the intake tuned to give best power at 9,400 RPM. Those are
>>>real Ohio HP. Not those little California HP used to sell race engines.
>>>
>>>A well done 13B Pport with very mild exhaust work should have 230 to
>>>250 continuous at 7,500 RPM. Plan fuel pickups for a 45 degree climb
>>>angle.
>>>
>>>If you only need 220 HP then the side port is quick and easy also.
>>>
>>>Lynn E. Hanover
>>>      
>>>
>>It's fun to bat around the incredible numbers a rotary is capable of,
>>but for most of us 160-200 hp at cruise is about the most our airframes
>>are designed for & can haul fuel for. Even big 4 seaters or very fast
>>glass can't use more than around 225 continuous hp efficiently (75% of
>>300 hp). The airframe drag going up means you just waste gas making more
>>hp than the airframe design speed calls for.
>>
>>The question I'd like answered is this: What configuration can be made
>>the most fuel efficient while making hp in this range?
>>
>>Should it be p-port & 2.1 redrive, p-port & 2.85, side-port & 2.85, etc
>>etc?
>>
>>My gut is betting on a small-diameter p-port & 2.85 drive, hoping for
>>good takeoff performance with a big, fixed pitch prop & keeping fuel
>>efficiency up turning whatever it takes to cruise at the above power
>>range. My needs in an RV-7 would be in the 160-180hp (actual cruise
>>power setting) & someone in an RV-10 would need 190-210 actual cruise hp.
>>
>>Charlie
>>