X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from rv-out-0910.google.com ([209.85.198.190] verified) by logan.com (CommuniGate Pro SMTP 5.1.11) with ESMTP id 2226221 for flyrotary@lancaironline.net; Thu, 02 Aug 2007 02:25:24 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.198.190; envelope-from=wdleonard@gmail.com Received: by rv-out-0910.google.com with SMTP id c27so296161rvf for ; Wed, 01 Aug 2007 23:24:46 -0700 (PDT) DKIM-Signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:references; b=pAooNN2c8VQQAUfwta4R0YEPW7SxEj8wRNhgawXjJS5YkffXDEyFbCl5wjeJfKhN+pViOCQnFMaVUjGkNg/FAWNCtnjp0zibAg/Ghu8BDUxbQ+OYXaeel30ogQ/AY782/v9G/hN33tPZvPuLI6iittZIX8igil6S2bsAUtuzKYA= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:references; b=pX3koBkkRyJGjmmmhb/QlalF2gC9X37dIz97Xwwc+t+EeANMRMwa2o/d4V8iPFMLHD93sP/207GEvbkkpeY3VVX0epxwTPVWwCN+LdbmxuXRA2hL3xrLvbiiVzXIQ82plqBBh5sPe8rOmK6LRg5QFGjkjov1IZ5UtEwhjtIklZU= Received: by 10.115.58.1 with SMTP id l1mr1491499wak.1186035885207; Wed, 01 Aug 2007 23:24:45 -0700 (PDT) Received: by 10.115.54.9 with HTTP; Wed, 1 Aug 2007 23:24:44 -0700 (PDT) Message-ID: <1c23473f0708012324w1c626404hfbe8158f14a9014d@mail.gmail.com> Date: Wed, 1 Aug 2007 23:24:44 -0700 From: "David Leonard" To: "Rotary motors in aircraft" Subject: Re: [FlyRotary] Redundant systems In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_67688_18813858.1186035884922" References: ------=_Part_67688_18813858.1186035884922 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Thanks for the report Gaylen. Glad to hear you are down safe. Strange about the blown circuit. Is it possible that there is something ne= w that made the coil burn more juice? --=20 David Leonard Turbo Rotary RV-6 N4VY http://N4VY.RotaryRoster.net http://RotaryRoster.net On 8/1/07, Gaylen Lerohl wrote: > > A few weeks ago Ed Anderson reported a failed circuit breaker feeding > both coils. He urged that we make our systems redundant where possible, > with separate circuits and circuit protection to each. I second his plea > and share my recent experience as reinforcement. > > > > I have about 60 flight hours and about 15 ground hours on my RV8. It is > powered by a 13B with the stock Mazda coils. Tracy recently updated my > EC2 and I installed it Saturday. After a half hour ground run adjusting > the MAP table I shut down and installed the cowl. Taking Tracy's advice = I > took off, stayed near the airport and did the Mode 9 programming at > altitudes of 7,000' to 10,000' AGL. I did several simulated approaches > and landings at altitude enjoying the smoother running engine compared wi= th > the previous iteration of the program. Also spent time among the puffy > clouds and cooler air above the haze layer! After 1.5 hours I began > simulating another approach but when I pulled the power to idle the engin= e > quit. Emergency procedures were fruitless. Even shutting down the entir= e > system and attempting a power-up didn't result in an engine start. I was > several miles from the field at about 7,000 AGL. I set up an 85 KT glide= , > and decided to land on a runway with a six KT tailwind to avoid flying ov= er > a residential area or over a lake on the approach to an alternate runway. > I arrived over the approach end of the runway on a crosswind leg with > 1500' to lose so I began a tight pattern flying a descending left turn to > lose altitude and position myself for the landing. I lost 500 feet in th= e > first 180 degrees and about the same in the second 180 degrees. I rolled > out on final high and hot, shut off all the electrics, landed long but > without incident. It all went pretty well other than the fact I forgot t= o > roll in flaps when I could have used the drag to get me down sooner. > > > > I use fuses for circuit protection so the first troubleshooting step was > to check the fuses =96 all were OK! I suspected the coils were involved > because the tachometer was reading zero even though the engine was > windmilling. The tach is driven by a signal from the trailing coil. Usi= ng > the new diagnostic features, the injectors were clicking OK but there wa= s > no spark. Tracy reminded me of Ed Anderson's post about the failed > breaker feeding both coils. Upon close examination the fuse had not blow= n > but apparently it has been warm because it had warped. It was in the fus= e > holder but somehow was not making contact. Replacing the fuse cured the > problem. > > > > I am now a firm advocate of redundancy! I have added a circuit to power > the coils separately and plan to replace the essential bus fuse panel wit= h > circuit breakers. I share this experience to urge those of you who use a > single circuit to power your coils, your fuel pumps, your EC2 or any othe= r > critical systems to modify your wiring so a single circuit failure doesn'= t > place you in a dangerous position. Mine ran for about 75 hours. It was > just a stroke of good fortune that the failure occurred while near the > airport at an altitude higher than I usually fly. > > > > Here are a couple of data points that may be of interest: > > The fixed pitch wood prop windmilled at a 100 KT glide, rate of > descent about 1000 FPM. > > The prop stopped at about 90 KT. > > > > Fly safe! > > Gaylen Lerohl > > RV8 > > Alexandria, Minnesota > > > > > > ------=_Part_67688_18813858.1186035884922 Content-Type: text/html; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
Thanks for the report Gaylen.  Glad to hear you are down safe.&nb= sp;
 
Strange about the blown circuit.  Is it possible that there is so= mething new that made the coil burn more juice? 

--
David = Leonard

Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.net
htt= p://RotaryRoster.net
On 8/1/07, G= aylen Lerohl <lerohl@gctel.net> wrote:

A few wee= ks ago Ed Anderson reported a failed circuit breaker feeding both coils.  He urged that we make our systems redundant where possible= , with separate circuits and circuit protection to each.   I second his plea and share my recent experience as rei= nforcement.

 

I have ab= out 60 flight hours and about 15 ground hours on my RV8.  It is powered by a 13B with the stock Mazda coils.  Trac= y recently updated my EC2 and I installed it Saturday.   After a half hour ground run adjusting the MAP table I = shut down and installed the cowl.  Taking Tracy's advice = I took off, stayed near the airport and did the Mode 9 programming at altit= udes of 7,000' to 10,000' AGL.   I did several simulated approaches and landings at alti= tude enjoying the smoother running engine compared with the previous iterat= ion of the program.  Also spent time among the puffy clou= ds and cooler air above the haze layer!   After 1.5 hours I began simulating another approach but= when I pulled the power to idle the engine quit.  Emerge= ncy procedures were fruitless.  Even shutting down the en= tire system and attempting a power-up didn't result in an engine start.   I was several miles from the field at about 7,000 AGL.<= span>  I set up an 85 KT glide, and decided to land on a runway= with a six KT tailwind to avoid flying over a residential area or over a l= ake on the approach to an alternate runway.   I arrived over the approach end of the runway on a cros= swind leg with 1500' to lose so I began a tight pattern flying a descending= left turn to lose altitude and position myself for the landing. = ; I lost 500 feet in the first 180 degrees and about the same in the second 1= 80 degrees.  I rolled out on final high and hot, shut off= all the electrics, landed long but without incident.  It= all went pretty well other than the fact I forgot to roll in flaps when I = could have used the drag to get me down sooner.

 

I use fus= es for circuit protection so the first troubleshooting step was to check th= e fuses =96 all were OK!  I suspected the coils were invo= lved because the tachometer was reading zero even though the engine was win= dmilling.   The tach is driven by a signal from the trailing coil.<= span>  Using the new diagnostic features,  th= e injectors were clicking OK but there was no spark.  Tra= cy reminded me of Ed Anderson's post about the failed breaker feeding both = coils.   Upon close examination the fuse had not blown but appar= ently it has been warm because it had warped.  It was in = the fuse holder but somehow was not making contact.  Repl= acing the fuse cured the problem.

 

I a= m now a firm advocate of redundancy!  I have added a circ= uit to power the coils separately and plan to replace the essential bus fus= e panel with circuit breakers.=20  I share this experience to urge those of you who use a s= ingle circuit to power your coils, your fuel pumps, your EC2 or any other c= ritical systems to modify your wiring so a single circuit failure does= n't place you in a dangerous position.   Mine ran for about 75 hours.  It was = just a stroke of good fortune that the failure occurred while near the airp= ort at an altitude higher than I usually fly. 

 

Here are = a couple of data points that may be of interest:

          The fixed = pitch wood prop windmilled at a 100 KT glide, rate of descent about 1000 FP= M.

          The prop s= topped at about 90 KT.

&n= bsp;

Fly safe!=

Gaylen Lerohl

RV8

Alexandria, Minnesota

 

 




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