X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from smtp102.vzn.mail.dcn.yahoo.com ([209.73.179.140] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with SMTP id 1148933 for flyrotary@lancaironline.net; Sat, 10 Jun 2006 11:49:07 -0400 Received-SPF: neutral receiver=logan.com; client-ip=209.73.179.140; envelope-from=pjmick@verizon.net Received: (qmail 81521 invoked from network); 10 Jun 2006 15:48:23 -0000 Received: from unknown (HELO ?192.168.1.44?) (pjmick@verizon.net@71.111.168.206 with plain) by smtp102.vzn.mail.dcn.yahoo.com with SMTP; 10 Jun 2006 15:48:22 -0000 Message-ID: <448AEA1E.8040802@verizon.net> Date: Sat, 10 Jun 2006 08:49:50 -0700 From: Perry Mick User-Agent: Mozilla/5.0 (Windows; U; Win98; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 To: flyrotary@lancaironline.net Subject: Re: [FlyRotary] Re: Ignition Failure Content-Type: multipart/alternative; boundary="------------000104040803010208070902" This is a multi-part message in MIME format. --------------000104040803010208070902 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit The crank angle sensor is a single point of failure. There is only one, so it's not redundant even if you have two controllers. However from my experience driving RX-7s (70 miles round trip to work for the last 10 years) I've never seen one fail. Haven't seen an ECU fail either. Occassionally one of my cars wouldn't start, I would unplug and then reseat the crank angle sensor connector and it would then start. I've only seen this phenomenon on one car. Probably just needed some contact cleaner. Generally I think any problem with the crank angle sensor would mean the engine wouldn't run at all. Might be good to have one controller running on the stock crank angle sensor and a second running from an independent sensor on the e-shaft front pulley. You can't have redundancy everywhere. I have one cranks sensor and one ecu and my engine has never quit running in 600 hours. If you really want redundancy build a plane like a twin-engine Defiant, that can truly fly on one engine. Perry ----------------- I understand that it's totally natural to feel defensive in this situation. I know you may find this hard to believe, but the goal of the post is to help others reduce risk. It's not a personal attack. There's no rotary reference in it anywhere. As far as the readers know it's a piston engine. But I hope there's at least one person on this list that sees value of looking at the other causes. The essence of the post is accurate. Doesn't matter if you are near home base or not. Ignition failure is very high risk item. An ECU that was better at self diagnoses would have greatly reduced your risk. On your car, it would be recognized immediately. Ecu would say "Hey, my cam sensor just went thru it's normal 50 pulses per revolution with the normal 5 and 8 ms. gaps. But I didn't get the normal 20 pulses and signal gaps from the crank sensor. Turn on warning lamp and crank code. Use cam sensor for timing info." You don't see value in discussing stuff like this? If you guys just used toothed wheel with pulse gaps, then the ECU could easily self diagnose. You know what was cool on the other list? Guys came back with "confessions" of how this parallels a problem they encountered. 2 guys said, "yeah, I had partial failure, thought it was x, took off only to find it was y". Then other guys described changes they made to system that totally eliminated the risk. Some really creative stuff. Then we discussed just how risky crank sensor really is...we see one ever 1 1/2 to 2 years. Etc. Etc. Very positive experience that may save someone's life. That's the goal. -al wick Artificial intelligence in cockpit, Cozy IV powered by stock Subaru 2.5 N9032U 200+ hours on engine/airframe from Portland, Oregon Prop construct, Subaru install, Risk assessment, Glass panel design info: http://www.maddyhome.com/canardpages/pages/alwick/index.html On Fri, 09 Jun 2006 23:30:00 -0400 John Slade > writes: Hi Tim, Isn't it wonderful how stories get twisted around as they fly from list to list. Obviously this particular twisted story relates to my recent experience, so let's dilute the fun a little by adding some truth. --------------000104040803010208070902 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit The crank angle sensor is a single point of failure. There is only one, so it's not redundant even if you have two controllers. However from my experience driving RX-7s (70 miles round trip to work for the last 10 years) I've never seen one fail. Haven't seen an ECU fail either. Occassionally one of my cars wouldn't start, I would unplug and then reseat the crank angle sensor connector and it would then start. I've only seen this phenomenon on one car. Probably just needed some contact cleaner.

Generally I think any problem with the crank angle sensor would mean the engine wouldn't run at all.

Might be good to have one controller running on the stock crank angle sensor and a second running from an independent sensor on the e-shaft front pulley.

You can't have redundancy everywhere. I have one cranks sensor and one ecu and my engine has never quit running in 600 hours. If you really want redundancy build a plane like a twin-engine Defiant, that can truly fly on one engine.

Perry

-----------------
I understand that it's totally natural to feel defensive in this situation. I know you may find this hard to believe, but the goal of the post is to help others reduce risk. It's not a personal attack. There's no rotary reference in it anywhere. As far as the readers know it's a piston engine.  But I hope there's at least one person on this list that sees value of looking at the other causes.
 
The essence of the post is accurate. Doesn't matter if you are near home base or not. Ignition failure is very high risk item. An ECU that was better at self diagnoses would have greatly reduced your risk. On your car, it would be recognized immediately. Ecu would say "Hey, my cam sensor just went thru it's normal 50 pulses per revolution with the normal 5 and 8 ms. gaps. But I didn't get the normal 20 pulses and signal gaps from the crank sensor. Turn on warning lamp and crank code. Use cam sensor for timing info." You don't see value in discussing stuff like this? If you guys just used toothed wheel with pulse gaps, then the ECU could easily self diagnose.
 
You know what was cool on the other list? Guys came back with "confessions" of how this parallels a problem they encountered. 2 guys said, "yeah, I had partial failure, thought it was x, took off only to find it was y". Then other guys described changes they made to system that totally eliminated the risk. Some really creative stuff. Then we discussed just how risky crank sensor really is...we see one ever 1 1/2 to 2 years. Etc. Etc. Very positive experience that may save someone's life. That's the goal.
 

-al wick
Artificial intelligence in cockpit, Cozy IV powered by stock Subaru 2.5
N9032U 200+ hours on engine/airframe from Portland, Oregon
Prop construct, Subaru install, Risk assessment, Glass panel design info:
http://www.maddyhome.com/canardpages/pages/alwick/index.html
 
 
 
On Fri, 09 Jun 2006 23:30:00 -0400 John Slade <sladerj@bellsouth.net> writes:
Hi Tim,
Isn't it wonderful how stories get twisted around as they fly from list to list. Obviously this particular twisted story relates to my recent experience, so let's dilute the fun a little by adding some truth.

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