Carbon monoxide

C

clarkmueller

Pre-Flight
Joined
Apr 2, 2012
Messages
91
Location
San Jose, CA
Display Name
Display name:
Clark
It's my hope that I don't have anything to contribute to Lessons Learned very often, but today I had an experience that I hope can help some others.

While on a relatively short flight back to home base with a couple of friends today, my carbon monoxide detector began alerting, and then indicated a rapid rise in carbon monoxide. We flushed the cabin and made a precautionary landing, and the hunt is now on for the source of the leak.

I'm sharing this here because while mostly a non-event in its outcome, this experience has made me a believer that everyone should fly with a proper carbon monoxide detector.

When I bought my airplane, I stuck a disposable CO detector on the panel. A CFI told me to throw it away, which gave me a push a few months ago to buy a Tocsin CO detector. Today, I was very happy to have it. The alerting functionality and the ability to see whether the CO levels were going up or down was invaluable. I'm very confident that without the alerting, I likely would never have noticed a problem until it was much more advanced.

If you're still using one of the disposable ones... throw it away and get something better!
 
Did you still have the disposable stuck to the panel? Did it "alert" indicating a problem?

I'm just wondering if the stick-ons are worthless or just slow to react (almost worthless)?

-Skip
 
Glad everyone was o.k.

Sticky's are better than nothing. I would imagine the important thing is make sure they are in date.

Slow down, open a window and land ASAP.
 
txflyer said:
Glad everyone was o.k.

Sticky's are better than nothing. I would imagine the important thing is make sure they are in date.

Slow down, open a window and land ASAP.
Click to expand...
And lean.

Running at peak or leaner makes a dramatic reduction in the engine out CO.
 
Skip Miller said:
Did you still have the disposable stuck to the panel? Did it "alert" indicating a problem?

I'm just wondering if the stick-ons are worthless or just slow to react (almost worthless)?

-Skip
Click to expand...

I kept it around for a while, but it was long past its best by date, so I tossed it before this happened. I do agree that the stickies are better than nothing, but I definitely place a value on the audible alerting.
 
This is very true. I use a digital co detector in the Pitts on every flight. The co levels are very noticeably higher when the mixture is rich. I believe every pilot should use a REAL co detector. I put one of those card ones in the tail pipe of my truck. Never did see it change color. My digital detect indicated hi levels of co within seconds. Just sayin.

Capt. Geoffrey Thorpe said:
And lean.

Running at peak or leaner makes a dramatic reduction in the engine out CO.
Click to expand...
 
Go to the Carbon Monoxide chamber in OKC and learn how you will react to it.
I've done the hypoxia one. It was awesome.
 
Skip Miller said:
Did you still have the disposable stuck to the panel? Did it "alert" indicating a problem? I'm just wondering if the stick-ons are worthless or just slow to react (almost worthless)? -Skip
Click to expand...
Skip - I use the stick-on detectors and they work. During a routine panel scan shortly after takeoff I noticed the color had changed to sky blue. It was the first cool morning of the season and the first time I had flown with all the fresh air vents closed. I immediately opened both wing vents in the C172 and was prepared to open my side window if needed. Took just a moment but as the cabin was flushed with air the color returned to normal. It took lots of tests with a digital CO reader before we figured out where the leak was coming from as the internal exhaust components / mufflers showed no signs of leaking. Turned out to be worn door seals.

Attached pic was taken by friend in the right seat during the flight. Here's a link to the one I have in the plane:
http://www.aircraftspruce.com/catalog/pspages/llifecodetectors.php
 

Attachments

  • CO-120212.jpg
    CO-120212.jpg
    70.6 KB · Views: 257
The DEAD STOP will alert in the Navion. This only happens to me when I'm sitting stationary on the ramp with the canopy open. Apparently the exhaust will pool in the cabin that way. With any forward airspeed, it's less of an issue. Inside the Navion canopy is higher pressure than the outside and most of the air flows in via the tail cone.
 
I've been very happy with a CO Experts line of alarms. I stick one on my panel with Velcro but you can put it on the floor or most anywhere. I think they are guaranteed for five years and the one I had a few iterations ago started beeping after three or four years with an end of life message. I wrote to Aeromedix and they sent me a brand new one.

It is accurate (yep, it'll sometimes go off when running the engine with the cowl off and full rich), compact, and lasts a long time. I love it and I too won't fly without some sort of CO detector.
 
We're real sensitive to CO now that we almost always fly with a parrot in the back seat.
 
Henning said:
:rofl::rofl::rofl: That's not a CO chamber, that's a pressure (or rather vacuum) chamber.
Click to expand...


I know. I have actually ridden that chamber.
My CFI took us there to show us hypoxia. I always joked "When do we get to do the carbon monoxide chamber?"
 
I would never be satisfied with just the stick-on indicator. When I was flying, I always had a CO monitor that would sound an alert, and even THAT was not enough to overcome the stupidity that set in one time when it went off.

I had been flying a year and was not yet instrument rated. The FBO had sold the 172 I had learned in, and a nice old gentleman let me fly his nice old 182 for a year or so until I bought my first plane (in which I got my instrument rating). This was a 1959 182 with an enclosed baggage compartment so that there was a rear shelf behind the back seat over the baggage compartment.

The son of the owner as a mechanic (and instrument rated pilot, although now I realize that, almost certainly, there was no way he was current). He had performed an annual on an Arrow for an airline pilot friend of his, and his mission was to fly the Arrow down to Fernandina Beach, FL from our home in NC to deliver it to the owner. The owner was then to fly us back to Allendale, SC, where the 182's owner would meet us and we would fly back home.

The mechanic invited me to fly left seat in the Arrow to get some retract time and experience instrument flying, so of course I accepted. The trip down was uneventful. The non-instrument 182 owner had scud run down to Allendale. The three of us then flew the 182 back home: me left seat, the mechanic right seat, the old man in the back seat. My flight bag (with the CO monitor in mesh side pocket) was on that back shelf, and of course we forgot all about it.

I was VERY stressed just flying the plane in the soup, sweating and concentrating. (This old 182 had ancient instruments in a haphazard arrangement, with the the old style Heading Indicator that operated like a whiskey compass "rotating backwards" [no DG type presentation], and the Attitude Indicator was this abstract thing that had no blue anywhere on it.)

We started hearing this chirping sound and had no idea where it was coming from. The two of us in the front seat are doing all we can just to keep the proper side up. The chirping goes on and on. Finally the old man in the back seat finds the source: my CO monitor. Our nerves were so frazzled and the alarm was hurting our concentration SO WE TOLD HIM TO THROW THE DAMN THING OUT!! I can't remember if he actually did or not, but somehow it never crossed our minds that we were actually being poisoned by carbon monoxide or not! I think that, eventually, we opened a window. We were near our destination/origin and continued on.

I firmly believe in a an audible alarm over the stick-on silent unit. There is no WAY that we would have noticed a color change on the latter, as it simply is not a part of the instrument scan.

Wells
 
I always thought that CO poisoning would be a rather pleasant way to go, so I don't bother with monitoring it.
 
SixPapaCharlie said:
I know. I have actually ridden that chamber.
My CFI took us there to show us hypoxia. I always joked "When do we get to do the carbon monoxide chamber?"
Click to expand...

We drove by the testing chamber on the tour, but didn't get to stop. I've always wanted to do it but I hear it's hard to get into or schedule.

You going through a CO chamber testing would explain a lot! :lol:
 
SixPapaCharlie said:
Put it on your bucket list.
It is a really cool experience
Click to expand...

Try going the other way and pressurizing up for a PPO2 2.5+ and taking a CNS O2 hit, it's interesting as well to see what happens to yourself when you go O2 rich. If you dive decompression dives and use O2 on deco, or air diving below 190', it's good to know your onset symptoms, because if it hits you underwater, you're probably going to die.
 
overdrive148 said:
This is the driving force behind doing it for me. Other than that it's cool and my dad did it for his RAF training.

Click to expand...

That is a great motivator but let's not forget the flatulence.
When else can you sit in a tube with mixed company you have never met and just tare it up and act like it's normal
 
Henning said:
I always thought that CO poisoning would be a rather pleasant way to go, so I don't bother with monitoring it.
Click to expand...
Yeah, but if you're unlucky, you'll survive it, and THAT can be uncomfortable.

I've told this story a number of times, but I got CO poisoning back in the early '70s. I was a CAP cadet, and flew in the right seat of a Mooney with two senior members in a ~400 mile night flight in a Mooney. Both the senior members were long-time pilots, and the PIC was a WWII B-25 pilot.

We got to Des Moines about 9 PM. The pilot really slammed the landing, and we kidded him about it.

At the terminal, the two adults decided to get a drink, and I started exploring the terminal. However, after a few minutes of walking, I started getting extremely dizzy. There was no way I was going to stay upright, so I did an emergency landing right in front of the airline terminals.

Now, in the Midwest in the '70s, when a teenager started staggering around and collapsed to the floor, there was only one reason: Drugs. I was hauled off to the security office by a cop with a clamp-like grip on my upper arm. I told them where to find my companions.

When they showed up, everyone started comparing notes I was dizzy, and the guy who'd ridden in the back seat had an absolutely splitting headache. The pilot was fine. We discussed it, and the back seater mentioned smelling exhaust when the engine started but not afterwards. We figured it was CO.

We went to our hotel. I basically collapsed for the rest of the night; the guy with the headache suffered. The pilot went out and got another drink.

The next day, the A&Ps found two holes the size of silver dollars in the heater manifold. We actually flew home the next day, with the heater off.

Since then, I've been reeeeallll sensitive about Carbon Monoxide. Despite what you might think, open-cockpit airplanes are not immune...the cockpit is a low-pressure area where CO can accumulate. Got a friend who got poisoned in a Starduster. About five years ago, we opened the heat exchanger during the annual and found soot all over inside one half...fortunately, the half that was feeding the carb heat.

I've got a meter I take up occasionally in my Fly Baby. I've measured as high as 80 PPM on the ground... wind from rear right quarter, probably combining with the prop blast to whip exhaust into the cockpit. Straight zeros (so far) in flight.

Ron Wanttaja
 
wanttaja said:
Since then, I've been reeeeallll sensitive about Carbon Monoxide. Despite what you might think, open-cockpit airplanes are not immune...the cockpit is a low-pressure area where CO can accumulate.
Click to expand...

Yep, the only time's I've seen the deadstop in the Navion turn was when the canopy was OPEN.
 
Henning said:
Makes me wonder what a regular pulse oximeter reads when you have CO poisoning? From what I understand it's a color densitometer, and CO makes it go red even when cyanotic.:dunno:
Click to expand...

That is exactly what happens. These fancier $5000+ CO have a better color differentiation (uses multiple wavelengths) to differentiate oxygen and CO absorptions.
 
My Swift is bad to suck CO in through the tail cone, especially on the ground with windows closed. I have a stick on type and it has turned dark. I crack a window and it clears up. I am pretty sensitive and get a headache immediately behind my ears when exposed to CO. The Stick on has turned colors anytime I've had the problem and it returns to normal much faster than my headache subsides.

I had an exhaust crack in my Starduster Too. Giving my daughters rides (separately), both said they didn't feel good and asked to land and neither is prone to airsickness. I wasn't feeling anything in the rear seat. After second one felt bad, I checked and found exhaust crack. Low pressure in cockpit was sucking exhaust into front pit badly.


Sent from my iPhone
 
Henning said:
Makes me wonder what a regular pulse oximeter reads when you have CO poisoning?
Click to expand...

To add to FlyingRon's comment, a PulseOximeter cannot be relied upon to detect carbon monoxide, only for oxygen saturation. In fact, a person dying of CO poisoning could read near 100% PO2.
 
Let'sgoflying! said:
To add to FlyingRon's comment, a PulseOximeter cannot be relied upon to detect carbon monoxide, only for oxygen saturation. In fact, a person dying of CO poisoning could read near 100% PO2.
Click to expand...
Now that's some good stuff.....could be the makings of a great article or two. :yes:
 
Let'sgoflying! said:
To add to FlyingRon's comment, a PulseOximeter cannot be relied upon to detect carbon monoxide, only for oxygen saturation. In fact, a person dying of CO poisoning could read near 100% PO2.
Click to expand...

What I'm wondering is the O2 reading even useable for O2 when you have CO poisoning, I don't think it would be, I think it would reporting 100% even if there was no free oxygen left in the blood.
 
Henning said:
What I'm wondering is the O2 reading even useable for O2 when you have CO poisoning, I don't think it would be, I think it would reporting 100% even if there was no free oxygen left in the blood.
Click to expand...

Not sure Henning. Must try it sometime. Ah, you go first!
 
Skip Miller said:
Did you still have the disposable stuck to the panel? Did it "alert" indicating a problem?

I'm just wondering if the stick-ons are worthless or just slow to react (almost worthless)?

-Skip
Click to expand...
I inspected an aircraft a couple years ago that had one, it was still in the wrapper. I ,mentioned that it won't work that way. then he told me when he takes it out of the wrapper it turns black the next flight.

I pulled his mufflers and showed him why.
 
Old Thread: Hello . There have been no replies in this thread for 365 days.
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.
Back
Top