Posted for "Chuck Jensen" <cjensen@dts9000.com>:

 I was curious if you'd considered the failure steps involved with
 something like a cracked exhaust header or fitting.  The break will
 start dumping hot gases into the cowl area (hence the advantage of
 thermocouples as fire detectors) but one is unlikely to see the wave
 length from an actual fire before the Uvtron will be triggered.  Do you
 want to let it progress all the way to a full blown fire before you are
 alerted?  Obviously, a fuel and some electrically driven fires will be
 visually apparent early on, but it seems like exhaust system failure,
 probably one of the leading causes of fires, would not be detected until
 you had a serious issue on your hands.  Just a thought.
 
 Chuck Jensen

"""
  I used a UVtron based fire detector designed by the robotics guys to
  help robots find fires in burning buildings.  I mounted it in a small
  project box and wired it to a big red light on my panel.  It only
  detects actual fire (flames), not light.  So, it won't trigger based
 on
  glowing exhaust headers, sunlight, etc.  Attached is a picture of the
  unit with the box open. The heart of the unit is the UVtron bulb,
 which
  is the clear bulb you can see mounted on the circuit board & standing
  upright within the box.  The "warning light" is the small LED lying on
  top of the box.  I ended up using a much larger LED than what is shown
  here.  You can assemble what you see in the picture for about $150.
  Hopefully, I'll never have to find out how well it works.
  
  Mark S.
  LNCE 208TX
"""