From: "Marvin Kaye" <marv@lancaironline.net>
Subject: visit with BIll Bradburry
To: flyrotary
Date: Sun, 18 Feb 2007 09:17:59 -0500
Message-ID: <web-1845241@logan.com>
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I had the good fortune to visit Bill Bradburry and his project yesterday.  It 
was a little nippy, but we survived the cold and Bill treated Don Gordon 
(another Lancair 320 flier) and myself to a thorough inspection of his Renesis 
installation, one that was quite impressive.  Compared to my Lancair 360, the 
space behind Bill's engine between the alternator and the firewall is 
absolutely cavernous.  He put the space to excellent use with his dual-pass 
radiator installation, which had a nicely crafted fiberglass plenum and input 
duct.  Everything on Bill's engine is readily accessible and his exhaust 
system is really beefy and well built.  We visited most of the systems, 
discussed those things that he'd have done a little differently if he knew 
then what he knows now, but in general it looked like his initial approaches 
with just about everything were right on target.

We dealt with a couple little electrical problems he'd discovered, nothing 
earth shaking, just simple wiring issues.  It was rewarding to be able to zero 
in on the problems in short order and lay them to rest.  We discussed others 
of the systems and one thing came to mind, which we discussed a bit, I thought 
I'd share it here.  Bill's ignition system, like most, includes a separate 
circuit for the igniters controlled by a single fuse.  Referring back to 
experience from the Eagle 540 installation which has 8 LS1 coils, one per 
spark plug, I observed that our coils were each treated to their own circuit, 
all fed by a free-standing fuse panel with 8 7.5-amp fuses, one per coil. 
 This means if any one coil were to fail and cause its fuse to blow we would 
still have 7 coils in full operation allowing the engine to keep running long 
enough to land and solve the problem with the failed coil.  Putting each 
ignitor on its own 7.5 or 10 amp circuit would offer that same level of 
redundancy, and would keep the remaining 3 plugs firing even if one coil were 
to fail and take out its associated fuse.  Something you may want to consider 
for your rotary installation.

Speaking of fuses vs breakers... there have been great arguments in both 
directions here and I'm not going to join in... this is a personal decision we 
each have to make and I know we will do so based on what we've learned and are 
comfortable with.  As far as fuses go, though, there is a little bit of 
circuitry that can be added to each fuse that will allow one to determine 
which fuse has blown, should one do so, from the briefest of glances at the 
fuse panel.  It includes a single LED mounted alongside each fuse, the way of 
its installation causing the LED to illuminate when the fuse blows.  I have a 
drawing of the circuit, it's very simple, requiring nothing more than an LED 
and a single current-limiting resistor, attached to each fuse circuit.  I'll 
dig it out and send it along when I locate it.  It actually came from a Sport 
Aviation article and may very well be online someplace already.

Well, that's about it for now.  I just wanted to thank Bill publicly for his 
hospitality and remind everyone to visit their fellow builders whenever they 
can.  It's always educational, great fun, and a way to put a faces to those 
names you've been seeing on all these emails for so long.  Enjoy!

   <Marv>