X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [207.189.223.49] (HELO email3.peakpeak.com) by logan.com (CommuniGate Pro SMTP 4.3c5) with ESMTPS id 936299 for flyrotary@lancaironline.net; Sun, 08 May 2005 00:58:02 -0400 Received-SPF: none receiver=logan.com; client-ip=207.189.223.49; envelope-from=billdube@killacycle.com Received: (qmail 23304 invoked by uid 513); 8 May 2005 05:50:18 -0000 Received: from 207.189.221.184 by email3 (envelope-from , uid 504) with qmail-scanner-1.23 (clamscan: 0.83 Clear:RC:1(207.189.221.184):. Processed in 0.459224 secs); 08 May 2005 05:50:18 -0000 Received: from 184-221-189-207.dyn.peakpeak.com (HELO tigger.killacycle.com) ([207.189.221.184]) (envelope-sender ) by email3.peakpeak.com (qmail-ldap-1.03) with SMTP for ; 8 May 2005 05:50:17 -0000 Message-Id: <4.3.1.0.20050507224645.040eca88@mail.chisp.net> X-Sender: billdube@mail.chisp.net X-Mailer: QUALCOMM Windows Eudora Version 4.3.1 Date: Sat, 07 May 2005 22:56:33 -0600 To: "Rotary motors in aircraft" From: "BillDube@killacycle.com" Subject: Detonation? (was: Seal Hrdness) In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed It occurred to me after I sent the last note that perhaps detonation cased the apex seal grove to wallow out and the apex seal to fail. This is just a guess on my part. On a piston engine, I have seen severe detonation shear the ring lands right off the pistons. This happened on a supercharged small block with stock pistons. The detonation was very severe, but brief (drag race.) The tops of the pistons did not have time to burn and melt like they would with more marginal, but long-term, detonation conditions. The force of the detonation did the damage directly rather than the high combustion temperatures. Just a though. Bill Dube http://www.killacycle.com/Lights.htm