X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [65.54.250.73] (HELO hotmail.com) by logan.com (CommuniGate Pro SMTP 5.0.9) with ESMTP id 1124794 for flyrotary@lancaironline.net; Tue, 23 May 2006 10:32:49 -0400 Received-SPF: pass receiver=logan.com; client-ip=65.54.250.73; envelope-from=lors01@msn.com Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Tue, 23 May 2006 07:32:02 -0700 Message-ID: Received: from 4.171.147.128 by BAY115-DAV1.phx.gbl with DAV; Tue, 23 May 2006 14:32:00 +0000 X-Originating-IP: [4.171.147.128] X-Originating-Email: [lors01@msn.com] X-Sender: lors01@msn.com From: "Tracy Crook" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: 100LL plug fouling / MPG Date: Tue, 23 May 2006 10:31:56 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0079_01C67E54.1D4BFE30" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: MSN 9 X-MimeOLE: Produced By MSN MimeOLE V9.20.0026.0800 Seal-Send-Time: Tue, 23 May 2006 10:31:56 -0400 X-OriginalArrivalTime: 23 May 2006 14:32:02.0557 (UTC) FILETIME=[A83E5AD0:01C67E75] This is a multi-part message in MIME format. ------=_NextPart_000_0079_01C67E54.1D4BFE30 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Good question but I don't know. The BSFC calcs I did were based on = Van's HP required vs IAS charts which were valid only near sea level = conditions. The nice thing about flying at altitude is the almost free = boost in airspeed. The HP required to fly the -4 at 175 mph at sea = level is a lot more than 76.6 HP. This is the main reason for the = longer "U2 wings" on my RV-8 which I plan to fly at 18,000 (or 17,999 = when I don't want to file IFR : ) Tracy=20 ----- Original Message -----=20 From: Perry Mick=20 I wasn't thinking very clearly last night, it's pretty obvious that = 175 / 6 is about 30 mpg. (29.2) If you are getting 0.47 lb/hr/HP, 6gph would work out to 76.6 HP, = sounds reasonable at that altitude. What do you think your actual BSFC is under these conditions?=20 If your mixture is about 17:1 lean and mine is 12:1 rich, that would = correlate well with 29 vs 21 mpg. Perry Tracy wrote: Yes, my head (and main scale of ASI) is still calibrated in miles per = hour. Yep, if you slowed down and were able to lean the mixture, your canard = should do better MPG than my RV. Tracy ----- Original Message -----=20 From: Perry Mick=20 To: Rotary motors in aircraft=20 Sent: Tuesday, May 23, 2006 12:56 AM Subject: [FlyRotary] Re: 100LL plug fouling / MPG Tracy, just so we are on the same page, I assume you mean 175 MPH = (not knots)? My data was taken between 10,500 and 12,500. It might be interesting = to see what my fuel burn and MPG would be if I slowed it down to 175 = MPH. Tracy wrote: About 30 mpg is what I currently see under best case conditions = (12,500 - 14,500 MSL, 6.0 gph, 175 TAS). Interesting experiment on way back from Lumberton. 4 RVs departed = for Florida Sunday AM, 3 Lyc powered and my rotary. The Lyc guys were = taking too long to get packed up (I get antsy when I'm ready to go) so I = left 15 minutes before they did and told them I would go slow and meet = up on the way since we were flying the same flight plan. The Lyc guys = flew at 8.5 GPH power setting and I flew at 6.0 GPH. Had head winds all = the way but interesting part was that after 2.75 hr and 370 miles after = my takeoff, the Lycs caught up to me. The extra speed of those 2.5 GPH = really does not buy much! And I got to spend more time in my beloved = airplane : )=20 Fun & Relaxing trip & fly-in BTW. =20 Tracy (must get Ed's Gin & tonic formula) From: Perry Mick=20 To: Rotary motors in aircraft=20 Sent: Monday, May 22, 2006 12:33 PM Subject: [FlyRotary] 100LL plug fouling Al Wick might have got some of his "100LL in rotary" comments from = my experience. I can't burn 100LL, it will foul my leading spark plugs after only = 4 hours. That is because my engine runs rich-best power all the time. Of = course running rich results in a higher fuel burn too. These days I'm = doing about 160 knots on 8.8gph, or 184 mph @ 21 mpg.=20 Burning mogas all the time, my leading spark plugs still only last = about 50 to 60 hours. Trailings always look better. My 1988 RX-7 with exactly the same engine gets about 18.5 mpg = combined city/hwy driving, probably low 20s if it was continuous = freeway. If I had lean control I would expect results more like Ed Anderson = with regard to 100LL and plug fouling. I would like to see some fliers express fuel usage in mpg, an easy = way to compare efficiencies. For example, Tracy and Ed leaning might see = 25 to 30 mpg? ------=_NextPart_000_0079_01C67E54.1D4BFE30 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Good question but I don't know.  The BSFC calcs I did = were based=20 on Van's HP required vs IAS charts which were valid only near sea level=20 conditions.  The nice thing about flying at altitude is the almost = free=20 boost in airspeed.  The HP required to fly the -4 at 175 mph at sea = level=20 is a lot more than 76.6 HP.  This is the main reason for the longer = "U2=20 wings" on my RV-8 which I plan to fly at 18,000 (or 17,999 when I don't = want to=20 file IFR : )
 
Tracy
----- Original Message -----
From: Perry Mick

I wasn't thinking very clearly last night, it's pretty obvious = that 175 /=20 6 is about 30 mpg. (29.2)
If you are getting 0.47 lb/hr/HP, 6gph = would work=20 out to 76.6 HP, sounds reasonable at that altitude.
What do you = think your=20 actual BSFC is under these conditions?

If your mixture is = about 17:1=20 lean and mine is 12:1 rich, that would correlate well with 29 vs 21=20 mpg.

Perry


Tracy wrote:

Yes, my head (and = main scale=20 of ASI) is still calibrated in miles per hour.
 
Yep, if you slowed down and were able to lean the mixture, your = canard=20 should do better MPG than my RV.
 
Tracy
----- Original Message -----
From: Perry Mick =
Sent: Tuesday, May 23, 2006 12:56 AM
Subject: [FlyRotary] Re: 100LL plug fouling / MPG

Tracy, just so we are on the same page, I assume you mean = 175 MPH=20 (not knots)?
My data was taken between 10,500 and 12,500. It might be = interesting to=20 see what my fuel burn and MPG would be if I slowed it down to 175 = MPH.
 

Tracy wrote:
 
About 30 mpg is what I currently see under best case conditions = (12,500=20 - 14,500 MSL, 6.0 gph, 175 TAS).
 
Interesting experiment on way back from Lumberton.  4 RVs = departed=20 for Florida Sunday AM, 3 Lyc powered and my rotary.  The = Lyc guys=20 were taking too long to get packed up (I get antsy when I'm ready to = go) so=20 I left 15 minutes before they did and told them I would go slow = and=20 meet up on the way since we were flying the same flight plan.  = The Lyc=20 guys flew at 8.5 GPH power setting and I flew at 6.0 GPH.  Had = head=20 winds all the way but interesting part was that = after 2.75=20 hr  and 370 miles after my takeoff, the Lycs caught up to=20 me.   The extra speed of those 2.5 GPH really does not buy = much!  And I got to spend more time in my beloved airplane :=20 ) 
 
Fun & Relaxing trip & fly-in BTW. =20   
 
Tracy  (must get Ed's Gin & tonic formula)
From: Perry Mick =
Sent: Monday, May 22, 2006 12:33 PM
Subject: [FlyRotary] 100LL plug fouling

Al Wick might have got some of his "100LL in rotary" comments = from my=20 experience.
I can't burn 100LL, it will foul my leading spark plugs after = only 4=20 hours. That is because my engine runs rich-best power all the = time. Of=20 course running rich results in a higher fuel burn too. These = days I'm=20 doing about 160 knots on 8.8gph, or 184 mph @ 21 mpg.
Burning mogas all the time, my leading spark plugs still only = last=20 about 50 to 60 hours. Trailings always look better.
 
My 1988 RX-7 with exactly the same engine gets about = 18.5 mpg=20 combined city/hwy driving, probably low 20s if it was continuous=20 freeway.
 
If I had lean control I would expect results more like Ed = Anderson=20 with regard to 100LL and plug fouling.
 
I would like to see some fliers express fuel usage in = mpg, an=20 easy way to compare efficiencies. For example, Tracy and Ed = leaning might=20 see 25 to 30=20 mpg?
------=_NextPart_000_0079_01C67E54.1D4BFE30--