X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 01 Oct 2007 12:09:23 -0400 Message-ID: X-Original-Return-Path: Received: from mtao02.charter.net ([209.225.8.187] verified) by logan.com (CommuniGate Pro SMTP 5.1.12) with ESMTP id 2362087 for lml@lancaironline.net; Mon, 01 Oct 2007 10:52:50 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.225.8.187; envelope-from=troneill@charter.net Received: from aarprv06.charter.net ([10.20.200.76]) by mtao02.charter.net (InterMail vM.7.08.03.00 201-2186-126-20070710) with ESMTP id <20071001145204.CCUV27011.mtao02.charter.net@aarprv06.charter.net> for ; Mon, 1 Oct 2007 10:52:04 -0400 Received: from axs ([75.132.198.100]) by aarprv06.charter.net with SMTP id <20071001145204.OLCY14098.aarprv06.charter.net@axs> for ; Mon, 1 Oct 2007 10:52:04 -0400 X-Original-Message-ID: <007001c8043a$a368ae60$6501a8c0@axs> From: "terrence o'neill" X-Original-To: "Lancair Mailing List" References: Subject: Re Static Thrust X-Original-Date: Mon, 1 Oct 2007 09:52:07 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_006D_01C80410.BA58AAA0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3138 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3138 X-Chzlrs: 0 This is a multi-part message in MIME format. ------=_NextPart_000_006D_01C80410.BA58AAA0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Just excellent data! =20 So your 42 lbs mass is being accellerated at 80% available (rpm) power, = your prop producing 220 lb. f. initial thrust, for 5.24 ft/sec/sec = accelleration ... without rpm increase to 62 mph. =20 Let's see, how can this be looked at for prop efficiency (n)? ... the = ave. torque for 99HP @ 2230 rpm would be about 240 lb.ft., and with = equal blade spanwise loading, about an approximate load center radius of = 1.25 ft. or less, or about 190 lbs. of torqueing force (drag)there, = assuming the drag is coming from the same radii as the thrust-lift... = and the prop produces thrust of 220 lb. f (like, lift)... actually much = more but some is swirled into anti-torque... How to think of this as efficiency? Is there a formula for that? Anyway, this info is reassuring and I shall proceed, and will publish = the results when I finally get flying.... Tested my 1990 wing tanks for leaks last week, and one seemed to; so = took off the drain valves and the gascaps, and found old O-rings on the = valve and one on the bolt throuogh the cap, and cleaned all up and = replaced the O-rings, and (VERY tankfully) that fixed it. I'll try the = silicon grease on the cap's lever base, as it had a lot of friction. Many thanks, Paul. =20 ----- Original Message -----=20 From: Paul Lipps=20 To: lml@lancaironline.net=20 Sent: Sunday, September 30, 2007 10:21 PM Subject: [LML] Static Thrust PSL 30.06", PSFC 29.72", MAP 28.25 Avg", OAT 15C, 2230 RPM, Thrust 220 = LB, HP=3D125 X2230/2800X28.25"/28.4"*=3D99HP.=20 ELIPPSE three-blade prop. 220 lb/(1350 lb/32.17) =3D 5.24 ft/sec^2 = initial acceleration=3D 17.3 sec to 62 mph without rpm increase and 784 = ft. * 28.4" is the typical MAP at SL conditions, a 1.5" drop across the = carburetor. There I was,sight-seeing around my home, wondering why my wing fuel = caps were so hard to close when I fueled it up, when I looked out at my = right wing. There was the cap sticking up 1/4"! Looking to the left, = same thing. I slowed down and returned to SMX. 'Turns out the cam lever = had so much friction it really wasn't seating and pulling the cone up = into the rubber donut. I applied silicon grease at the base of the cam = lever and between the donut and cone. 'Locking just fine now! ------=_NextPart_000_006D_01C80410.BA58AAA0 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
Just excellent = data! =20
So your 42 lbs mass = is being=20 accellerated at 80% available  (rpm) power, your prop producing 220 = lb. f.=20 initial thrust, for 5.24 ft/sec/sec accelleration ... without rpm = increase to 62=20 mph. 
Let's see, how can = this be=20 looked at for prop efficiency (n)?   ... the ave. torque = for 99HP=20 @ 2230 rpm would be about 240 lb.ft.,  and with equal blade = spanwise=20 loading, about an approximate load center radius of 1.25 ft.  or = less, or=20 about 190 lbs. of torqueing force (drag)there,  assuming the drag = is coming=20 from the same radii as the thrust-lift... and the prop = produces thrust of=20 220 lb. f (like, lift)... actually much  more but some is swirled = into=20 anti-torque...
How to think of = this as=20 efficiency? Is there a formula for that?
Anyway, this info = is reassuring=20 and I shall = proceed, and=20 will publish the results when I finally get flying....
 
Tested my 1990 wing = tanks for=20 leaks last week, and one seemed to; so took off the drain valves and the = gascaps, and found old O-rings on the valve and one on  the bolt = throuogh=20 the cap, and cleaned all up and replaced the O-rings, and (VERY = tankfully) that=20 fixed it.  I'll try the silicon grease on the cap's lever base, as = it had a=20 lot of friction.
 Many thanks, = Paul. =20
----- Original Message -----
From:=20 Paul=20 Lipps
Sent: Sunday, September 30, = 2007 10:21=20 PM
Subject: [LML] Static = Thrust

PSL = 30.06",=20 PSFC 29.72", MAP 28.25 = Avg", OAT 15C,=20 2230 RPM, Thrust 220 LB, HP=3D125=20 X2230/2800X28.25"/28.4"*=3D99HP. 
 
ELIPPSE three-blade prop. 220 lb/(1350 = lb/32.17) =3D 5.24=20 ft/sec^2 initial acceleration=3D 17.3 sec to 62 mph without rpm = increase and 784=20 ft.
 
* 28.4" is the typical MAP at SL conditions, a = 1.5" drop=20 across the carburetor.
 
There I was,sight-seeing around my home, = wondering why=20 my wing fuel caps were so hard to close when I fueled it up, when I = looked out=20 at my right wing. There was the cap sticking up 1/4"! Looking to the = left,=20 same thing. I slowed down and returned to SMX. 'Turns out the cam=20 lever had so much friction it really wasn't seating = and pulling the=20 cone up into the rubber donut. I applied silicon grease at the base of = the cam=20 lever and between the donut and cone. 'Locking just fine=20 now!
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