X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 06 May 2010 17:11:59 -0400 Message-ID: X-Original-Return-Path: Received: from qmta03.emeryville.ca.mail.comcast.net ([76.96.30.32] verified) by logan.com (CommuniGate Pro SMTP 5.3.6) with ESMTP id 4250164 for lml@lancaironline.net; Thu, 06 May 2010 14:15:00 -0400 Received-SPF: pass receiver=logan.com; client-ip=76.96.30.32; envelope-from=j.hafen@comcast.net Received: from omta15.emeryville.ca.mail.comcast.net ([76.96.30.71]) by qmta03.emeryville.ca.mail.comcast.net with comcast id EBrs1e0011Y3wxoA3JERQl; Thu, 06 May 2010 18:14:25 +0000 Received: from [10.0.1.4] ([24.17.111.171]) by omta15.emeryville.ca.mail.comcast.net with comcast id EJEQ1e00B3hvfg88bJEQ8F; Thu, 06 May 2010 18:14:25 +0000 From: John Hafen Mime-Version: 1.0 (Apple Message framework v1078) Content-Type: multipart/alternative; boundary=Apple-Mail-33-657203473 Subject: Re: [LML] Re: Cabin Door Window-IV-P X-Original-Date: Thu, 6 May 2010 11:14:23 -0700 In-Reply-To: X-Original-To: "Lancair Mailing List" References: X-Original-Message-Id: <77100001-11FA-4655-B5FB-155E2E498189@comcast.net> X-Mailer: Apple Mail (2.1078) --Apple-Mail-33-657203473 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 Are you sure the noise wasn't from dosing off and nodding forward, = hitting the top of your headset on the ceiling -- and hearing a "thump" = in your headset before waking up again? Happens to me all the time. Found out there's nothing wrong with the = plane. John Hafen On May 5, 2010, at 6:24 PM, Colyn Case wrote: > My noise didn't sound like it was coming from the engine. more like = something banging on the fuselage. Just happened 2 or 3 times and then = stopped. I had done some carbon work since the last flight so possibly = it was some bubbles popping but it seemed loud for that. >=20 > My engine is set up for 45 gph in the climb. >=20 > On May 4, 2010, at 4:23 PM, Robert Pastusek wrote: >=20 >> Colyn, >> =20 >> On the loud banging/popping, could the engine be pre-igniting? This = will definitely cause what you describe, and is definitely not good on = it. Do you climb at full rich mixture? If so, pre-ignition is not = likely=85but possible. If you are leaning in the climb, try pushing in = the mixture the next time it happens to see if that corrects it. Also, = you can get a pop/bang from =93after-fire=94 in descent with the mixture = rich. This is caused by unburned fuel being dumped into the exhaust = during descent when the engine is essentially windmilling=85not = producing much power=85 The fuel mixture will occasionally ignite in the = exhaust stack causing a definite pop/bang. >> =20 >> You=92ve got the old window for asking. I don=92t have it out = yet=85probably be June as my =93real work=94 is significantly = interfering with my fun these days, but I intend to try to get it out in = one piece so I can try to see where the break started, and why. >> =20 >> According to Ed, the crankshaft failed between the bearing journal = and the prop flange=85right in the radius. Ed says you can see a crack = through at least half the material, then the rest =93tore off=94, = bending/distorting the metal in the process. Don=92t know if this was = one of the =93bad=94 Continental cranks that got through the check of a = few years ago or not. The NTSB has the engine and is analyzing now. = Expect to hear more about this when available. >> =20 >> Bob >> =20 >> =20 >> From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf = Of Colyn Case >> Sent: Monday, May 03, 2010 6:40 PM >> To: lml@lancaironline.net >> Subject: [LML] Re: Cabin Door Window-IV-P >=20 --Apple-Mail-33-657203473 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252 Are = you sure the noise wasn't from dosing off and nodding forward, hitting = the top of your headset on the ceiling -- and hearing a "thump" in your = headset before waking up again?

Happens to me all the = time. Found out there's nothing wrong with the = plane.

John = Hafen

On May 5, 2010, at 6:24 PM, = Colyn Case wrote:

My noise didn't sound = like it was coming from the engine. more like something banging on = the fuselage. Just happened 2 or 3 times and then stopped. = I had done some carbon work since the last flight so possibly it was = some bubbles popping but it seemed loud for that.

My = engine is set up for 45 gph in the climb.

On May = 4, 2010, at 4:23 PM, Robert Pastusek wrote:

On = the loud banging/popping, could the engine be pre-igniting? This will = definitely cause what you describe, and is definitely not good on it. Do = you climb at full rich mixture? If so, pre-ignition is not likely=85but = possible. If you are leaning in the climb, try pushing in the mixture = the next time it happens to see if that corrects it. Also, you can get a = pop/bang from =93after-fire=94 in descent with the mixture rich. This is = caused by unburned fuel being dumped into the exhaust during descent = when the engine is essentially windmilling=85not producing much power=85 = The fuel mixture will occasionally ignite in the exhaust stack causing a = definite pop/bang.
Lancair = Mailing List [mailto:lml@lancaironline.net] On Behalf Of Colyn = Case
Sent: Monday, May 03, 2010 6:40 = PM
To: lml@lancaironline.net
Subj= ect: [LML] Re: = Cabin Door = Window-IV-P

= --Apple-Mail-33-657203473--