X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from m12.lax.untd.com ([64.136.30.75] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with SMTP id 1149253 for flyrotary@lancaironline.net; Sat, 10 Jun 2006 19:21:43 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.136.30.75; envelope-from=alwick@juno.com Received: from m12.lax.untd.com (localhost [127.0.0.1]) by m12.lax.untd.com with SMTP id AABCJYW7HAW7HX2J for (sender ); Sat, 10 Jun 2006 16:20:07 -0700 (PDT) Received: (from alwick@juno.com) by m12.lax.untd.com (jqueuemail) id LSJSXW2B; Sat, 10 Jun 2006 16:19:34 PDT To: flyrotary@lancaironline.net Date: Sat, 10 Jun 2006 16:01:27 -0700 Subject: Re: [FlyRotary] Re: Ignition Failure Message-ID: <20060610.161856.2780.2.alwick@juno.com> X-Mailer: Juno 5.0.33 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary=--__JNP_000_7943.2e63.6757 X-Juno-Line-Breaks: 8-6,12-13,18-26,28,36-37,39-40,43-44,48-53,59-60,70-71,79-90,92-93,96-104,105-32767 From: al p wick X-ContentStamp: 5:2:62848320 X-MAIL-INFO:18d8d861dd9848f838c95961b559c14c1128ad5975395885dd75ad28751c75a9d18c9d7cd8bc615c61f5dd18c1b17118f898698cb935dce86889f171e8cdec4d251cfc2525f9ec09fc2d61dc1c08e5aceccc2119dce9b16d214cbd49492da81d2d39 X-UNTD-OriginStamp: L941HVjjYzDhN3itp//mkAgTeYS8gaHkvoyndjr9VdhnOkJoww/+Tw== X-UNTD-Peer-Info: 127.0.0.1|localhost|m12.lax.untd.com|alwick@juno.com This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. ----__JNP_000_7943.2e63.6757 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit One of the creative solutions that was offered, had two crank sensors. Two ECU's. I think he said it was Tec system or something like that. One ECU and crank sensor is used for normal operation, but it activates a relay if it ever loses crank sensor. That relay powers second ECU and second crank sensor. The guy tested it by unplugging sensor and it works. I was impressed. As I told him, way better than my system. As I mentioned, this is relatively low frequency failure. But the EFFECT when it fails is pretty severe (loss of power). The frequency is so low, that it's unlikely you would experience it in your 600 hours. On top of that, you have stock wiring, so much lower risk. I know of three out of four where wiring was the direct cause. -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 Sat, 10 Jun 2006 08:49:50 -0700 Perry Mick writes: 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. -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 ----__JNP_000_7943.2e63.6757 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: quoted-printable
One of the creative solutions that was offered, had two crank sensors.= Two=20 ECU's. I think he said it was Tec system or something like that. One ECU = and=20 crank sensor is used for normal operation, but it activates a relay if it = ever=20 loses crank sensor. That relay powers second ECU and second crank sensor. = The=20 guy tested it by unplugging sensor and it works. I was impressed. As I told= him,=20 way better than my system.
 
As I mentioned, this is relatively low frequency failure. But the = EFFECT=20 when it fails is pretty severe (loss of power). The frequency is so low, = that=20 it's unlikely you would experience it in your 600 hours. On top of that, = you=20 have stock wiring, so much lower risk. I know of three out of four where = wiring=20 was the direct cause.
 

-al wick
Artificial intelligence in cockpit, Cozy IV powered by= =20 stock Subaru 2.5
N9032U 200+ hours on engine/airframe from Portland,=20 Oregon
Prop construct, Subaru install, Risk assessment, Glass panel = design=20 info:
http:= //www.maddyhome.com/canardpages/pages/alwick/index.html
On Sat, 10 Jun 2006 08:49:50 -0700 Perry Mick <pjmick@verizon.net> writes:
The crank angle sensor is a single point of failure. There is only = one,=20 so it's not redundant even if you have two controllers. However from my=20 experience driving RX-7s (70 miles round trip to work for the last 10 = years)=20 I've never seen one fail. Haven't seen an ECU fail either. Occassionally = one=20 of my cars wouldn't start, I would unplug and then reseat the crank angle= =20 sensor connector and it would then start. I've only seen this phenomenon = on=20 one car. Probably just needed some contact cleaner.

Generally I = think=20 any problem with the crank angle sensor would mean the engine wouldn't = run at=20 all.

Might be good to have one controller running on the stock = crank=20 angle sensor and a second running from an independent sensor on the e-= shaft=20 front pulley.

You can't have redundancy everywhere. I have one = cranks=20 sensor and one ecu and my engine has never quit running in 600 hours. If = you=20 really want redundancy build a plane like a twin-engine Defiant, that can= =20 truly fly on one engine.

Perry

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

-al wick
Artificial intelligence in cockpit, Cozy IV powered = by=20 stock Subaru 2.5
N9032U 200+ hours on engine/airframe from Portland,=20 Oregon
Prop construct, Subaru install, Risk assessment, Glass panel = design=20 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=20 wonderful how stories get twisted around as they fly from list to list.=20 Obviously this particular twisted story relates to my recent experience, = so=20 let's dilute the fun a little by adding some truth.

 

-al wick
Artificial intelligence in= =20 cockpit, Cozy IV powered by stock Subaru 2.5
N9032U 200+ hours on=20 engine/airframe from Portland, Oregon
Prop construct, Subaru install, = Risk=20 assessment, Glass panel design=20 info:
http://www.maddyhome.com/canardpages/pages/alwick/index.html
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