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NTSB Asks FAA To Require CO Detectors For GA Aircraft

CO detector

Walt: Do you have a preferred unit that you install? I will install one and hope that a different “certified” model isn’t required later by the gov.

Don Broussard
RV9 Rebuild in Progress
57 Pacer
 
Mine

Installed mine during build.
Really simple; all details are in Garmin G3X install manual.
Relatively cheap.

They are easy to install during build if using a glass panel, there is no reason not too. JMHO
 
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I'm leaning towards the Forensics. Recommended by an FAA Safety Inspector/Friend.
 
Forensics Lab for me

I use this: https://www.forensicsdetectors.com/products/car-vehicle-aircraft

Also have the little stick on 'color dot' detector: https://www.mypilotstore.com/MyPilo...RY8YJ7-jJNIH6-64CdIDD3wdCrP7k45xoCoDkQAvD_BwE

That article is a hoot! It reminds me of a Safety message on a military base Marquee '47 Private Vehicle deaths this year, 37 wearing seat belts' You intuitively get the meaning but the actual information given doesn't support the desired conclusion, in fact it supports the opposite.

CO detectors may save your life, that's true. They may not help you at all, also true. The data lent by NTSB supports the latter. My Foresnics device has stopped functioning a few times, needing replacement. So far the useful life is less than a year. How much less I have no idea. The Aussie (Kiwi?) that runs that company is great to work with and a fun guy to talk to. When did my device stop working?...Who knows! There isn't any kind of functional built in test. If you want confidence in those devices you have to test them pretty regularly (before each flight?), and DON'T shove them up your car's tailpipe!

The color dot indicator also is predictably dead in the 12 months advertised. When do they become ineffective? I check them when I buy a new lot but after that have no idea.

Hypobaric Chamber training is probably a more reliable tool in your arsenal, good for all kinds of Hypoxia not just Hypemic Hypoxia.

Nice effort by NTSB, but not a valid Safety message. Imagine if the FAA agreed: We would then need to know that it works or should be working prior to flight, and if it does not?


Safety is no accident
 
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My personal experience

I had a CO experience in a car when I was 20 in the navy. Me and a buddy were heading to Pensacola after work. Our ship was in the yards in Mobile, AL. Got in my car and headed across Mobile Bay. By the time we were a mile or two down the bridge we were both yawning uncontrollably. I felt lots of heat floating in from under the back seat and quickly realized what was happening. Rolling the windows down we were able to get our heads out just enough. Made it to the eastern shore and got it fixed. Huge crack in the muffler. I can see how quickly this can become a MAJOR emergency real fast.

I've looked at CO detecters for the plane but admit I don't have one... yet. I want one before my next cross country. In the mean time, I devised an area of my checklist in case I notice those same type of symptoms.

cabin heat …..off
mixture …..aggressively lean
cabin …..vents open-> close

NOTE: If leaning and venting fails, shut
down engine and again vent
cabin. While holding breath,
restart then shutdown & vent as
needed to make airport or
suitable off field landing site.
Declare emergency.
 
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Interesting. Coincidentally just installed the Aithre Shield EX 2.0 behind the Dynon HDX in my RV12 this past week. It's nice having a 'set it and forget it' install with alerts.
 
What if my plane leaks so much air under the canopy that I always have a fresh air supply in the cabin? ;):D
 
A CO detector is probably a good idea, but is that something that needs a regulation?

Based on the NTSB review, in 38 years of data there have been 31 CO-related accidents. And one of those did have a CO monitor installed.

If memory serves 99% of GA accidents are pilot error (split between running out of gas and loss of control?), perhaps mandating more frequent flight reviews would give a better safety outcome than mandating CO detectors.
 
I use the Aithre in my own airplane and with my panel installs.

Same here...wired to Dynon SkyView, works great! Install was a piece of cake, good for 10 years before refurbishment is required. Sensitive enough to pick up the CO levels in the outside air to a 1 PPM match with SCAQMD data. And pretty inexpensive to boot.
 
I am curious. Can blood oxygen measurements by an apple watch be used to detect carbon monoxide poisoning?

Either way I do agree that we don't need another regulation on this. Knowing the FAA they will require one in my open cockpit DR-1 ... .

Oliver
 
I am curious. Can blood oxygen measurements by an apple watch be used to detect carbon monoxide poisoning?

Either way I do agree that we don't need another regulation on this. Knowing the FAA they will require one in my open cockpit DR-1 ... .

Oliver

No, one of the dangerous things about CO is that it has an even higher (240x) affinity for hemoglobin than oxygen, and a pulse oxygen reader cannot distinguish between hemoglobin saturated with CO vs Oxygen, so it will be falsely high in the case of CO poisoning.
 
C/O monitors

Pulse oximeters are NOT an indicator of C/O levels. They read the red blood cells which the C/O has a lot greater of affinity to attach than O2. You can be at lethal levels of C/O and the pulse ox will read fine. I also think the colored dot detectors are worthless. By the time the dot changes, you are probably at a lesser mental capacity to realize it. I personally have a home battery operated unit in my RV. Just make sure the detector is less than 10 years old. The sensors go bad after that. ( And check your smoke and C/O detectors for age in your house, please). Ben. (FYI 30 year EMT and firefighter)
 
I personally have a home battery operated unit in my RV. Just make sure the detector is less than 10 years old.

As I understand it, the problem with home units being used in aircraft (or boats, for that matter) is that they take a much longer time to respond, as their design environment is radically different.

The Forensics Detectors mentioned above, among many many others, explain ti on their website (q.v.):

Can I Use a Home CO Detector for Aircraft?

No, that is a bad idea. A typical CO home detector will not suffice as it will alarm too late for such a small confined space. A home CO alarm is programmed to alarm at 70 ppm in 60 minutes. This is way too slow and the alarm trigger point is too high.

Or Aviation Consumer:

Residential Detectors

There are dozens of household CO detectors, some with prices not much above those of the chemical spot detectors. We do not recommend any of the residential detectors as most follow Underwriters Laboratories spec UL-2034, which requires a time delay before the unit will alarm once a given level of CO is present. That’s to cut down on calls to 911 for false alarms. Under the UL spec, if the unit has a digital readout, it cannot show CO concentrations below 30 PPM. The unit will not sound an alarm until CO reaches 70 PPM and remains there for four hours. At a concentration as high as 400 PPM, the unit will generally not alarm for 15 minutes.

Given the effect of flight at altitude in combination with low-level CO poisoning, we think it’s quite likely a pilot would be incapacitated well before a household detector would alarm in flight.
 
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I use one of these bad boys. Very small and I can hear the beep and see the light. Good attention getter. I know it works too because it went off while I was in line for departure at OSH.

Co detector
 
CO detector temp range

Looked at both Mel's and Walts units good to -10* C. kind of a joke around most the places I fly for 4 month out of the year.
 
I also have the Aithre wired into my Skyview. Works great and was. Simple to install. Interesting to see readings change during taxi and flight.
 
If you're interested in the Sensorcon CO monitor, you can get 20% off at their website. There is an article reviewing the detector in Flyer magazine (UK Feb 2022) that explains a lot. I have no connection to the company, just found a little known good deal ... use code Aircraft2021

And for what it's worth, the website states: "... designed and assembled in our Western New York Facility"

Sensorcon AV8 Inspector and AV8 Inspector Pro

https://www.sensorcon.com/pages/av8-inspector-collection
 
If you go west, VFR, from the eastern parts of the country, after a while you'll see the mountains in the distance. That is a helpful CO detector.

Dave
Boulder, CO
 
G3X

For those that use a CO2 detector with the G3X system. The CO2 detector shows being connected to the GDU460 via an RS-232 bus. The G3X diagram shows the audio will then be ported from the GDU-460 to the GMA245 via wiring. The Garmin manual also states the CO2 message traffic will be shared from the GDU460 via the CAN bus.

The question is, will the audio alert still transfer from the GDU460 to the GMA245 if the CO2 detector is linked into a 2nd GDU460 on the CAN bus that is not directly ported into the GMA 245 (PFD vs MFD sort a speak).

Whew, that was a mouthfull of numbers. I'll call the G3 experts monday, but thought it worth asking. Sorry for the scope creep, trying to update a drawing diagram and curious if this path works.
Capture 1.PNG
 
Just me

For those that use a CO2 detector with the G3X system. The CO2 detector shows being connected to the GDU460 via an RS-232 bus. The G3X diagram shows the audio will then be ported from the GDU-460 to the GMA245 via wiring. The Garmin manual also states the CO2 message traffic will be shared from the GDU460 via the CAN bus.

The question is, will the audio alert still transfer from the GDU460 to the GMA245 if the CO2 detector is linked into a 2nd GDU460 on the CAN bus that is not directly ported into the GMA 245 (PFD vs MFD sort a speak).

Whew, that was a mouthfull of numbers. I'll call the G3 experts monday, but thought it worth asking. Sorry for the scope creep, trying to update a drawing diagram and curious if this path works.
View attachment 21326

I have a separate audio from the gd-40 to the gma245.
I am still trying to figure out to display the co value on the gdu, but it is not a priority for me, so i havent bother to think too hard about this.

But i get the audio alerts and have the separate idiot light and reset switch above the gdu
 
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GD-40

We installed a GD-40 in the -10 and have it wired into the audio panel for audible alerts and the Dynon as well so it pops up an alert on the screens. There is also a red warning led on the panel and a reset/test button. I had an experience in a van that had an exhaust leak. Started feeling not well and layed down in the back row that I had all to myself. Well no one knew but it had an exhaust leak and a bug had crawled into one of the floor drains and died, sticking the drain open. The symptoms are very hard to pinpoint as it’s such an uncommon thing to happen. Of course a co detector is a waste of time and money……….until you need it!
 
I have had a GUARDIAN CO Detector wired to my DYNON SkyView since 2012 so no whining about it for me. The visual alarm activates the master caution while the audio alarm is hardwired into my intercom. You can see the module next to the Co-Pilot display on my panel.

Completed Panel 2021.jpg

:cool:
 
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Oshkosh Talk

I listened to the Hypoxia talk at Oshkosh 2021, it was very informative.

One thing I didn't know is that the onset of hypoxia from CO posioningcannot be self diagnosed.

If one thinks they will be able to tell if they are having the early symptoms and be able to open up a vent and prevent hypoxia, the real life data does not show this. I think the euphoria one gets during the early stages overwhelms the ability to self detect. One thing his data showed is that the blood oxygen saturation level goes UP with the onset of hypoxia due to CO causing false readings. In fact, the suggestion was made that a higher than normal blood oxygen level may be an early sign of hypoxia. JMHO.

Corrected: normal hypoxia can be noticed and treated if personnal symptons are recognized. But CO poisoning will come on without warning.
 
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GD-40

Panel space required for indicator & selftest button. Circuit board is mounted under the panel.
 

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I listened to the Hypoxia talk at Oshkosh 2021, it was very informative.

One thing I didn't know is that the onset of hypoxia cannot be self diagnosed.

I don't really agree with this statement. In Navy/Marine aviation we trained in the hypobaric chamber specifically to acquaint ourselves with recognizing hypoxia onset.

Flight rules said we were to wear 100% oxygen from start up to shut down, but in practice most of us just self monitored and breathed the oxygen when needed. Operating without supplemental oxygen at a cabin altitude in the mid 20s was pretty standard even if the texts said it wasn't possible.

Had a flight early on as a 1Lt in the back of a two seater with a crusty Colonel who asked me to take off my mask and secure my oxygen during a X-Cntry in the high 40ks' because he needed a smoke. Nearly 30k' cabin alt and all the CO that goes with cigarettes.

Not smart, not right, but self monitoring one's oxygen saturation is entirely doable. Something that can be learned in a controlled environment.

The accounts of those that have survived hypemic hypoxia by CO inhalation seem to all include the classic symptoms prior to being disabled. Perhaps not recognized due to lack of experience, but all there.

Strolled into my walk in fridge in my brewery one day and got three steps in and realized there was no oxygen through the rapid onset of hypoxic hypoxia (yah, hypoxic hypoxia...it's a real term). A large CO2 bottle had leaked out overnight and displaced most, if not all of the breathable air at nose level. You'd think you would detect the sting of the CO2 but when it's really cold you miss it. Unfortunately folks in the beer/wine industry die every year this way. (Usually bending over the side of an active or recently emptied fermenter) Those sessions in the hypobaric chamber helped me that day and can help any aviator, good stuff and available to all.

Recommend following FARs on oxygen use, and get some hypobaric chamber training, or the new normobaric hypoxia chamber! It can save your life.
 
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I listened to the Hypoxia talk at Oshkosh 2021, it was very informative.

One thing I didn't know is that the onset of hypoxia cannot be self diagnosed.

If one thinks they will be able to tell if they are having the early symptoms and be able to open up a vent and prevent hypoxia, the real life data does not show this. I think the euphoria one gets during the early stages overwhelms the ability to self detect.

John,
Respectfully, I think you're confusing basic hypoxia with carbon monoxide (CO) poisoning. Stated simply, hypoxia is a deficiency in the amount of oxygen (O2) reaching body tissues. There are 6 different types of hypoxia, each brought about by different conditions external or internal to the body.

In the USAF, we hit the altitude chamber every 4 years specifically to experience our own personal hypoxia symptoms, and how they change over time. It was that very training that helped me recognize my own hypoxia event in the F-4, which I dealt with immediately as I was trained. My symptoms: An unusual warm feeling all over, fuzzy stars along the visual periphery with associated gray tunneling, loss of color acuity, and cyanosis (purpling) of my fingernails. I gang-loaded my O2 regulator to 100%/Emergency, and fealt better immediately. That was hypoxic hypoxia, a general lack of sufficient oxygen to the body. The onset of most hypoxia symptoms can most definitely be diagnosed...

...but not always.

Carbon monoxide causes hypemic hypoxia, when the body is unable to transport a sufficient supply of the oxygen that is available. Because the CO molecules 'displace' the O2 molecules in the red blood cells, they reduce the amount of O2 being carried to the brain, eyes, and tissues. Hypoxia from CO poisoning is much more insidious than other forms of hypoxia. It impairs the brain's functions, judgement, and mental faculties such that you cannot mentally process that it's happening to you, what to do about it, or even recognize that something must be done. Replenishing the lungs with O2 may not clear up the problem, depending on how much CO has been absorbed by the red blood cells--there's no room for the good O2 molecules.
 
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Thank you

John,
Respectfully, I think you're confusing basic hypoxia with carbon monoxide (CO) poisoning. Stated simply, hypoxia is a deficiency in the amount of oxygen (O2) reaching body tissues. There are 6 different types of hypoxia, each brought about by different conditions external or internal to the body.

In the USAF, we hit the altitude chamber every 4 years specifically to experience our own personal hypoxia symptoms, and how they change over time. It was that very training that helped me recognize my own hypoxia event in the F-4, which I dealt with immediately as I was trained. My symptoms: An unusual warm feeling all over, fuzzy stars along the visual periphery with associated gray tunneling, loss of color acuity, and cyanosis (purpling) of my fingernails. I gang-loaded my O2 regulator to 100%/Emergency, and fealt better immediately. That was hypoxic hypoxia, a general lack of sufficient oxygen to the body. The onset of most hypoxia symptoms can most definitely be diagnosed...

...but not always.

Carbon monoxide causes hypemic hypoxia, when the body is unable to transport a sufficient supply of the oxygen that is available. Because the CO molecules 'displace' the O2 molecules in the red blood cells, they reduce the amount of O2 being carried to the brain, eyes, and tissues. Hypoxia from CO poisoning is much more insidious than other forms of hypoxia. It impairs the brain's functions, judgement, and mental faculties such that you cannot mentally process that it's happening to you, what to do about it, or even recognize that something must be done. Replenishing the lungs with O2 may not clear up the problem, depending on how much CO has been absorbed by the red blood cells--there's no room for the good O2 molecules.

Thank you for clearing this up.
 
My understanding of chemistry is that if you run lean-of-peak, CO poisoning is unlikely. Could happen when climbing at rich settings I suppose.
 
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