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 5.0.8) with SMTP id 990211 for flyrotary@lancaironline.net; Sat, 18 Feb 2006 14:08:52 -0500 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 AABB9Q6EFA6WBYC2 for (sender ); Sat, 18 Feb 2006 11:07:49 -0800 (PST) Received: (from alwick@juno.com) by m12.lax.untd.com (jqueuemail) id LHHXYUMF; Sat, 18 Feb 2006 11:06:57 PST To: flyrotary@lancaironline.net Date: Sat, 18 Feb 2006 11:05:23 -0800 Subject: Re: [FlyRotary] Re: Another Turbo? Message-ID: <20060218.110602.2184.2.alwick@juno.com> X-Mailer: Juno 5.0.33 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary=--__JNP_000_56ce.27d5.0ad1 X-Juno-Line-Breaks: 8-6,7-8,17,23-24,26-27,31-32,35-44,46,54,56-59,61-66,70-72,74-76,78-89,90-32767 From: al p Wick X-ContentStamp: 12:6:172247049 X-MAIL-INFO:3debeb1bceb37ffee7472f1b672f23da0b9ea32f8b8ac35bce8ba39e8b3e8b6e27e31ec7eb5f1bae1b8ece5723776f57feb38fe3eaf3d77f7f4b2efb8f3ef30efb034be3fa1f875af7fe7a4383efd3139f5e9b5edbe72a37aabb77f7dedadadf973ad3ce631a5b X-UNTD-OriginStamp: L941HVjjYzDhN3itp//mkJXVLoD5PbzJnouYQwAnHPk7BK95wHP2wQ== 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_56ce.27d5.0ad1 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Of course it was the exhaust side that died. I just wasn't thinking. A real good method to reduce your risk is to assume every failure will happen to you. Once you make that assumption, the next step is to make your engine insensitive to the failure. So, a screen at exhaust header would be a good example. We know it wouldn't last, but the concept is valuable. Perhaps a little dip in your exhaust manifold would be enough to slow down the debris. Just a little bend in the tubing might be enough. Moving the turbo further from the exhaust port. Every inch reduces risk. It's not going to take much of a change to reduce your risk to near zero. Only after you've give thought to reducing the EFFECT of the failure, do you consider ways to prevent the failure. So for John, sounds like going to larger turbo will keep the rpm below failure zone. That's his preventive action. I"m considering that and measuring turbo rpm dynamically. Not sure if I can do it. But it would give me huge advance notice of turbo problem. So if you both take action to prevent fault, AND action to reduce the effect, you've got good system. For my plane, I'm going to assume every thing that happened to John will happen to me. I don't plan on allowing myself to say stuff like "that's because it's a rotary". That serves little purpose. So I place great value in his and other peoples reports. Sure appreciate all the suggestions. Between the private postings and list postings I've got quite a list of action items now. I'll post it here if you guys interested. -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, 18 Feb 2006 09:41:51 -0800 "Todd Bartrim" writes: Yea, I'm starting to remember something about this now, as I was quite surprised at the time that the fragment from the exhaust turbine had gone back up into the engine. An intercooler won't help you there and a screen isn't possible either. But really what are the odds that this would happen (I mean for anyone other than John" Turbo Killer" Slade)? Was this just an anomaly or is this a common failure. Some of you follow some of the rotary auto racing lists, have you heard of this type of failure before? I guess what I'm asking is this something us turbo guy's should worry about and if so is there anything we can do about it? Todd (need to turn off the Olympics and get back to building my shop) -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]On Behalf Of John Slade Sent: Saturday, February 18, 2006 7:45 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Another Turbo? As for strainers, I don't believe John's blown turbo had any damage on the compressor side. IIRC, he believes the turbine side somehow through a piece back into the engine. I'm confident that he'll correct me if I got that wrong :-) Which turbo are we talking about? The second turbo sent turbine fragments back into the exhaust port and took out an apex seal. This cost me a housing, a set of seals and a drive to North Carolina. I'm pretty confident that there was no engine damage from this current failure where a turbine blade broke off. Yes, I do have an intercooler. John (off to install the big one) -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_56ce.27d5.0ad1 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: quoted-printable Message
Of course it was the exhaust side that died. I just wasn't thinking. <= /DIV>
 
A real good method to reduce your risk is to assume every failure will= =20 happen to you. Once you make that assumption,  the next step is to = make=20 your engine insensitive to the failure. So, a screen at exhaust header = would be=20 a good example. We know it wouldn't last, but the concept is valuable. = Perhaps a=20 little dip in your exhaust manifold would be enough to slow down the debris= .=20 Just a little bend in the tubing might be enough. Moving the turbo further = from=20 the exhaust port. Every inch reduces risk. It's not going to take much of a= =20 change to reduce your risk to near zero.
Only after you've give thought to reducing the EFFECT of the failure, = do=20 you consider ways to prevent the failure. So for John, sounds like going to= =20 larger turbo will keep the rpm below failure zone. That's his preventive = action.=20 I"m considering that and measuring turbo rpm dynamically. Not sure if I can= do=20 it. But it would give me huge advance notice of turbo problem.
 
So if you both take action to prevent fault, AND action to reduce the= =20 effect, you've got good system.
 
For my plane, I'm going to assume every  thing that happened to = John=20 will happen to me. I don't plan on allowing myself to say stuff like "that'= s=20 because it's a rotary". That serves little purpose. So I place great value = in=20 his and other peoples reports.
 
Sure appreciate all the suggestions. Between the private postings and = list=20 postings I've got quite a list of action items now. I'll post it here if = you=20 guys interested.

-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, 18 Feb 2006 09:41:51 -0800 "Todd Bartrim" <bartrim@gmail.com> writes:
    Yea, I'm starting to remember something about= this=20 now, as I was quite surprised at the time that the fragment from the = exhaust=20 turbine had gone back up into the engine. An intercooler won't help you = there=20 and a screen isn't possible either. But really what are the odds that = this=20 would happen (I mean for anyone other than John" Turbo Killer" Slade)? = Was=20 this just an anomaly or is this a common failure. Some of you follow some= of=20 the rotary auto racing lists, have you heard of this type of failure=20 before?
    I guess what I'm asking is this something us = turbo guy's=20 should worry about and if so is there anything we can do about=20 it?
 
Todd    (need to turn off the Olympics and get = back to=20 building my shop)
-----Original Message-----
From: Rotary motors in = aircraft=20 [mailto:flyrotary@lancaironline.net]On Behalf Of John=20 Slade
Sent: Saturday, February 18, 2006 7:45 AM
To:= =20 Rotary motors in aircraft
Subject: [FlyRotary] Re: Another=20 Turbo?

= As for=20 strainers, I don't believe John's blown turbo had any damage on the=20 compressor side.  IIRC, he believes the turbine side somehow = through a=20 piece back into the engine.  I'm confident that he'll correct= me=20 if I got that wrong :-) 
&= nbsp;
Which turbo are we talking about?
The second turbo sent turbine fragments back into the exhaust = port=20 and took out an apex seal.
This cost me a housing, a set of seals and a drive to North=20 Carolina.
 
I'm pretty confident that there was no engine damage from this= =20 current failure where a turbine blade broke off.
 
Yes, I do have an intercooler.
John (off to install the big one)
 
 
 

-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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