X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [24.25.9.103] (HELO ms-smtp-04-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 5.0.7) with ESMTP id 965240 for flyrotary@lancaironline.net; Thu, 02 Feb 2006 16:28:47 -0500 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.103; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-025-165.carolina.res.rr.com [24.74.25.165]) by ms-smtp-04-eri0.southeast.rr.com (8.13.4/8.13.4) with SMTP id k12LS1aY014254 for ; Thu, 2 Feb 2006 16:28:02 -0500 (EST) Message-ID: <001d01c6283f$90ee8800$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Suitability of NPG for Rotary Engine use Date: Thu, 2 Feb 2006 16:28:10 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_001A_01C62815.A7C04DE0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_001A_01C62815.A7C04DE0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi Dave, Really appreciate you taking the time out of your undoubtedly busy = schedule to give us your perspective on use of the NPG in the rotary. I = did want to stir up the nest a bit on the topic - and it appears I did = {:>). Humm, I thought I had stuck to comparing the 50/50 and NPG+ = although I did mention pure water being the "best". I'll have to be = more careful. Clearly, folks have use NPG in an airborne rotary (ken and you at a = minim) and apparently found it satisfactory - except perhaps for is = availability on trips. I agree that is more environmentally friendly = (non-toxic) compared to Ethylene. Theoretical analysis is fun and = interesting - but, nothing proves(or disproves) it like the real world. Perhaps because I have never experienced any boil-over or other inflight = cooling problem in 8 years of flying, I have found no deficiency with = the glycol/water mixture approach. I am still not certain what to make = of your assessment that the use of a 7 psi cap may have contributed to = your loss of coolant. My understanding was that was one of the benefits = of NPG - a non-pressurized coolant system. I suppose that the high = altitude and low PSI cap could have played a factor in your situation - = but then that's where we operate our engines. I decided to see if I could find an authoritative source on the = flammability of Propylene Glycol on the web. This is what I found: Propylene glycol is colourless, odourless and viscous liquid = (hygroscopic). Boiling point 187.4 to 189 OC=20 Half-life in air <10.012 hrs ( Interesting fact - wonder what it = means?) Flammability Slight Explosive Properties Containers may explode in heat or flame So it appears that as long as you don't carry a can of it near your = exhaust, looks like you don't have to worry about flamability of it. =20 There are two cases I am aware of where the rotary engine loss cooling = capability - one was the loss of coolant and the other was a belt = failure that stopped the water pump. In both case, the aircraft = continued to produce power long enough to get the aircraft to a runway. = In one case I am most familiar with, it was 10 plus minutes without = cooling, including a go-around (due to conflicting traffic), don't know = how long the other guy flew before landing. All the rubber seals was = cooked in the one case (10 minutes) and the pilot stated that when = poured coolant into the engine it leaked like a sieve. In any case, hope you find the time to get to the engine before you = leave - can't imagine sitting over there for several months without = knowing the cause {:>). Thanks again Dave. Ed A =20 ----- Original Message -----=20 From: David Leonard=20 To: Rotary motors in aircraft=20 Sent: Thursday, February 02, 2006 3:04 PM Subject: [FlyRotary] Re: Suitability of NPG for Rotary Engine use The HP is the easy part. Get the cooling right first. Lynn E. Hanover Very true. Will the "right" cooling system please stand up! My cooling system is too small for the power I wanted to be able to = use. I could still outrun any 160 hp RV-6 and outperform those with 180 = hp and fixed pitch props. =20 But I was out-climbed by the guys with 180hp and c/s props and outrun = by the 200 h.p. crowd. =20 This should have been good enough. Flying n.a. there were no cooling = issues at all. But I am starting to think that cooling is like money. No matter how = much you have, its never quite enough. My current plan it to go from a 2" rad to a 3" rad of the same or = larger surface area. I will also add some fresh intake ducting, a cowl = flap, and spray system. That should allow me to easily beat the 200h.p. guys.... but then = there is always the tri-aviathon... Any suggestions? :-) --=20 Dave Leonard Turbo Rotary RV-6 N4VY http://members.aol.com/_ht_a/rotaryroster/index.html http://members.aol.com/_ht_a/vp4skydoc/index.html ------=_NextPart_000_001A_01C62815.A7C04DE0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hi Dave,
 
Really appreciate you taking the time out of = your=20 undoubtedly busy schedule to give us your perspective on use of the NPG = in the=20 rotary.  I did want to stir up the nest a bit on the topic - and it = appears=20 I did {:>).  Humm, I thought I had stuck to comparing the 50/50 = and NPG+=20 although I did mention pure water being the "best".  I'll have to = be =20 more careful.
 
Clearly, folks have use NPG in an = airborne rotary=20 (ken and you at a minim) and apparently found it satisfactory - except = perhaps=20 for is availability on trips.  I agree that is more environmentally = friendly (non-toxic) compared to Ethylene. Theoretical = analysis is fun=20 and interesting - but, nothing proves(or disproves) it like the = real=20 world.
 
Perhaps because I have never experienced any = boil-over or=20 other inflight cooling problem in 8 years of flying, I have = found no=20 deficiency with the glycol/water mixture approach.   I am = still not=20 certain what to make of your assessment that the use of a 7 psi cap may = have=20 contributed to your loss of coolant.  My understanding was that was = one of=20 the benefits of NPG - a non-pressurized coolant system.  I suppose = that the=20 high altitude and low PSI cap could have played a factor in your = situation - but=20 then that's where we operate our engines.
 
I decided to see if I could find an = authoritative source=20 on the flammability of Propylene Glycol on the web.  This is what I = found:

Propylene glycol is colourless, odourless and viscous = liquid=20 (hygroscopic).

 Boiling point 187.4=20 to 189 OC 

Half-life in air <10.012 hrs  ( Interesting fact - wonder what it means?)

Flammability = Slight

Explosive Properties Containers may explode in heat or=20 flame

So it appears that as long as you don't carry a = can of it=20 near your exhaust, looks like you don't have to worry about flamability = of=20 it.
 
There are two cases I am aware of where the = rotary engine=20 loss cooling capability - one was the loss of coolant and the other was = a belt=20 failure that stopped the water pump.  In both case, the aircraft = continued=20 to produce power long enough to get the aircraft to a runway.  In = one case=20 I am most familiar with, it was 10 plus minutes without=20 cooling, including a go-around (due to conflicting traffic), don't = know how=20 long the other guy flew before landing.  All the rubber seals was = cooked in=20 the one case (10 minutes) and the pilot stated that when poured coolant = into the=20 engine it leaked like a sieve.
 
In any case, hope you find the time to get to = the engine=20 before you leave - can't imagine sitting over there for several months=20 without  knowing the cause {:>).
 
Thanks again Dave.
 
Ed A
 
----- Original Message -----
From:=20 David=20 Leonard
Sent: Thursday, February 02, = 2006 3:04=20 PM
Subject: [FlyRotary] Re: = Suitability of=20 NPG for Rotary Engine use



 
 
The HP is the easy part. Get the cooling right first.
 
Lynn E. Hanover
 
 
 
Very true.  Will the "right" cooling system please stand = up!
 
My cooling system is too small for the power I wanted to be = able to=20 use.  I could still outrun any 160 hp RV-6 and outperform those = with 180=20 hp and fixed pitch props. 
 
But I was out-climbed by the guys with 180hp and c/s props and = outrun by=20 the 200 h.p. crowd. 
 
This should have been good enough.  Flying n.a. there were = no=20 cooling issues at all.
 
But I am starting to think that cooling is like money.  = No=20 matter how much you have, its never quite enough.
 
My current plan it to go from a 2" rad to a 3" rad of the same or = larger surface area.  I will also add some fresh intake = ducting, a cowl flap, and spray system.
 
That should allow me to easily beat the 200h.p. guys....  = but then=20 there is always the tri-aviathon...
 
Any suggestions?  :-)

--
Dave = Leonard
Turbo=20 Rotary RV-6 N4VY
http://memb= ers.aol.com/_ht_a/rotaryroster/index.html
http://members= .aol.com/_ht_a/vp4skydoc/index.html=20 ------=_NextPart_000_001A_01C62815.A7C04DE0--