Do You Have a CO Detector? Every pilot is trained in private pilot training how
insidious and deadly CO is and how easy CO can enter the cabin via single engine heater
system malfunctions, twin-engine 100LL burning nose heaters and just plain old
exhaust leaks that can get in the cabin.
The FAA now "recommends" that aircraft
owners install a CO detector in their aircraft via this
This SAIB is in response to a National Transportation Safety
Board (NTSB) investigation of an accident on December 17, 2000, where a Beech
Model BE-23 aircraft impacted terrain killing the commercial-rated pilot, the
sole occupant of the airplane. The NTSB determined the probable cause of the
accident was in part “the pilot’s incapacitation due to carbon monoxide (CO) and
a fractured muffler.”
Read the FAA CO Detection and Prevention Report
CSOBeech visitor Paul S. has the following thoughts on CO:
VERY informative...... WITHOUT an exhaust system failure....(( from appendix
==> panel mounted CO detectors are the best indicators, across the board,
based on location.
==> lower left at pilot's legs in a low wing is consistently the highest
level reading location.
==> low wing aircraft have twice the LEVEL of recorded CO in normal
operations as high wing.
==> low wing aircraft have twice the NUMBER of recorded CO events in normal
operations as high wing.
==> alarm levels should be set at 35ppm
I have been chasing a slight CO intrusion with certain vent/heat/air settings
in my N35.
I have determined that the left wing fresh air vent is a major culprit on the
ground & in climb.
Peaks have been at 75ppm.
My wife & I both can "feel" anything above 20ppm after a few minutes.
I have purchased a CO Guardian panel unit that will display 10ppm and higher.
I have been using an UEi calibrated hand-held CO detector/recorder in flight.
If I close all my fresh air vents & the front heat vents (leaving only heat
or unheated air coming out at the back seat footwell, my suction (hat shelf &
baggage floor) draws exhaust back in from the rear fuselage thru the shoulder
harness inertia reel ceiling openings.
Even LOP in cruise I can see as high as 25ppm in the back seats.
Be careful up there.
Click the below image for a larger version:
See my Kidde CO Detector Cockpit Alert
HERE. It's CSOB available from Wal~Mart, Home Depot and Lowes for something
like $30 and has a nice digital display of the CO PPM level that it is seeing.
Kidde Model #: KN-COPP-B P/N:
900-0146 / User Manual
Previously Mounted in my B55
This model CO Detector helped
my buddy in his N35 Bonanza get a heads up on his exhaust system while he was
flying across Florida.
After I had installed my Kidde CO Detector, my buddy Don
liked it's footprint and the general idea of some CO warning device. So he got
one for his N35 and not long after putting it in his plane he was on a trip with
his elderly Mom from Tampa to Miami and the detector went off.
opened all the windows he could and got on the ground quickly. What he found was
that his exhaust system on the right side had separated from the pipe to the
inlet of the muffler. Need I say more? Imagine something like this happening at
night on a long trip at cruise altitude......no, let's not! Nuff said.......
Here is the one I'm using today since the one
above reached "End Of Life" in 2018. A whopping $20 at any Home Depot store.
Here is another new option @ ~$100, for a compact sized panel mounted (2.7" x 2") sensitive detector available at Amazon
Recently, another CO save story surfaced from
a Bonanza owner, Paul S., that had seen my Kidde CO Detector and put one of them
in his recently purchased Bonanza. His pre-flight includes checking the stored
values in the CO detectors memory. He found a 31 ppm value in the memory and
went hunting for the source of the leak.
He stopped at Paul McCracken's (RIP) repair facility at
in McKinney, TX and had his exhaust system inspected. They found muffler cracks
in seams that, if left undiscovered, would have created quite a problem down the
Here is Paul's account:
I'd stopped @ Biggs' on my way home. CO of 31ppm and some
slight exhaust residue on the cabin heat SCAT. Flew to Paul McCracken's (see
above muffler photo). I also run LOP & still had some low levels of CO this past
Made an effort to seal up the cabin & improve the heating last
annual and this winter had very low 17 to 20 ppm values. I have the V35 scoop
mod for overhead fresh air, a side scoop to vent from the hat shelf AND a bottom
scoop to vent from the baggage area. With partial heat cabin on, the overhead
fresh air scoop taped over and the front fresh air vents taped over, I suck
exhaust in thru the tail into the cabin thru holes for the shoulder harness
inertia reels (also installed @ annual) Confirmed with sensitive CO monitor &
various flights. Now I do not tape over the inlets, and the heat still is
sufficient. No CO.
Early warning system? You bet! Remember, CO is
invisible and has no detectable odor so it is incredibly insidious.
Another CO tip: Running
GOP or Lean of Peak dramatically reduces CO
(still unhealthy levels but reduced), so you
Rich of Peak Operators take note that you have another reason to get off that
fuel wasting and harmful engine operating zone.
Below is a picture of what Bonanza owner Nathan
L., found after seeing that his CO detector card had turned dark!
And here is his
quote: "I am switching to a mounted alarm such as the ones you find in
your house. I feel lucky I saw the color in the detector change but an alarm
would have alerted me sooner. i was already tired and drowsy, flying at night,
and the only one awake in the plane. I shudder to think of the consequences if I
had not noticed this."
In most cases we are flying
decades old equipment and components. Items like this need to be checked
thoroughly for integrity as this is one of the things that can kill you and your
passengers! It would be wise to perform thorough exhaust system inspections,
especially on older exhaust components AND install some form of CO
warning/detection device. Just my humble opinion.
Periodically test your CO Detector with this CO
Beech Lister Stu B. uses the Testo 317-3 unit. A
professional level instrument. Seen on Ebay brand new for $215.
HERE for $204 on 1/11/2009
Aeromedix has an aviation
CO Detector Model #2010, currently selling for $179.
The CO Experts Monitor model 2010 provides both
audio and visual alarms starting at 7 PPM, while UL - 2034 listed CO alarms
are required to begin alerts at 30 PPM! This low level alert bests all UL
listed CO detectors by 23 PPM!
For other certified CO Detectors for your Aircraft
see: CO GUARDIAN
Check out the FAA SAIB #CE-10-19 on CO Detectors
Check out the FAA Report on CO Detection and