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What CO detection do you use?

Webb

Well Known Member
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Last year I put a CO Guardian in my Bonanza. I didn’t bother to take the button card down. On my last flight, the Guardian had a yellow warning light come on. No red or flashing red bit just a notice of a trace amount of CO. The card showed nothing.

No heat on, nothing different than a normal day with usual ventilation.

So I pulled the scat hose from the heat muff to the air box for my first search. The picture shows what was found on the backside. It looks cut, most likely a rub when the new engine was installed. So when I put the new one on, I will make darn sure it is clear from any potential edges that can cause a repeat.

Point is, carbon monoxide can show up when least expected. Please review how can identify it.

If you are using a button card, do you trust it? I don’t.
 

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I am gonna bite the bullet and get a LightSpeed Delta headset with the built in CO detector.

My LightSpeed Sierra is officially for sale. Actually it is my backup that is for sale…. You know the one your wife never wears :)
 
CO Detector

Forensics CO Detector on mine. Very small, has small mounting case (with 3m tape) , stuck right to panel in line of site eye level. Audible + visual warnings. Maddening though, as I can never get 0ppm in climb or slow flight. 14-25ppm usually. Clears easily when in cruise.
 
CO in the cabin..........

Maddening though, as I can never get 0ppm in climb or slow flight. 14-25ppm usually. Clears easily when in cruise.

Hmmmm... Your firewall should not let any CO in the cabin area. Is it time to check all your firewall passthroughs? And make sure the firewall is sealed in the proper areas..... Just a thought.........:cool:
 
After my recent experience, I’m encouraging all pilots to use some type of active monitoring device. A one time static detector (AKA card) only shows CO has been detected but since it is passive, there is no alert and you can’t tell when it detected it unless you were looking at it often. And it’s a one shot deal. My card didn’t detect the trace and it makes me wonder how often pilots put a fresh card in.

You can get a battery portable for under $50 with an alarm.

My in-panel detector alerted me to a problem. And I found it and fixed it before I needed to start using heat which would have greatly increased the PPM.

Since we do so many things for safety reasons while building and flying, I think this topic belongs at the top of the list.

Who knows what it may tell you if you put one on board and didn’t have one.

Your call.
 
CO detector alarm.....

You can get a battery portable for under $50 with an alarm.

All good points. The card is old technology and, at the time, the only reasonable thing available. Technology has made them obsolete, I think. CO is a nasty villain being odorless and tasteless. I nearly died of CO poisoning in a cabin outside of Yellowstone years ago so have some experience :eek::eek::eek:. Not much fun.

Make sure your CO alarm is audible wearing your ANRs. I know some pilots who have put theirs on their shoulder harness to be able to hear it....
 
Hmmmm... Your firewall should not let any CO in the cabin area. Is it time to check all your firewall passthroughs? And make sure the firewall is sealed in the proper areas..... Just a thought.........:cool:

In most of our airplanes the exhaust comes into the cabin through the tailcone. It would be difficult to plug this path as it must be open for the controls to pass. The best one can do is try and seal the canopy and wing passages well so the cabin underpressure is minimized.

That said, 25 ppm is quite a lot. I would look into redesigning the exhaust geometry, either to the side or extending further down. A couple of inches can make a big difference (she said).

Back to the OP. The card detectors are next to useless: if you are lucky enough to look at it as it turns black, you're already incapacitated. For many years I used the $120 digital ones from Spruce, those were fine. Then a few years ago I bought a $30 chinesium knock-off from eBay and tested them side-by-side. I was surprised to find that the $30 one was superior in every respect: much faster reaction, louder alarm, bigger more legible screen, common batteries. YMMV, but at those prices get two...
 
Here is the link to the story about a friend of mine. Please make sure you have some sort of good CO detector. Dan was very very fortunate. Listen to the podcast if you can.

https://www.aopa.org/training-and-safety/online-learning/real-pilot-stories/dan-bass-accident-photos

I personally use the Forensics CO detector but have it installed directly in front of me so I can see the light flashing if it detects a problem. The aural alarm is impossible to hear for me. The are other and better units listed above but please get something more than the card type or the $30 home detector type.

Keith
 
Hmmmm... Your firewall should not let any CO in the cabin area. Is it time to check all your firewall passthroughs? And make sure the firewall is sealed in the proper areas..... Just a thought.........:cool:

In most of our airplanes the exhaust comes into the cabin through the tailcone. It would be difficult to plug this path as it must be open for the controls to pass. The best one can do is try and seal the canopy and wing passages well so the cabin underpressure is minimized.

That said, 25 ppm is quite a lot. I would look into redesigning the exhaust geometry, either to the side or extending further down. A couple of inches can make a big difference (she said).


For sure will be doing all of that at next condition. Already have an email out to Vetterman for entire new exhaust system. Has the old style with ball joints that are now frozen and probably leaky slip joints. Has the old dog-bone connectors. I didnt build it. But, slowly making her "mine" . The detector was a must have before I ever started my transition training.
 
Maddening though, as I can never get 0ppm in climb or slow flight. 14-25ppm usually. Clears easily when in cruise.

We get exhaust gasses in the cabin that enter through the tailcone. Full rich mixtures are high in CO because there was not enough oxygen in the mix to completely combust the carbon in the fuel into CO2. Leaning as you climb and in slow flight (a low power setting) can help.
 
How did you interface? Is it a separate interface directly to the Skyview Network, or do you pin it into the main EFIS harness?

It's not a network device; it gets one of the pins on the EMS (I'll have to look at my schematics to see which one I used). Dynon has instructions on pin-out and widget configuration. Easy-peasy.

ETA: Just checked... +5V and GND using the same source from the EMS that is used for A/P servos, and I used pin 23 for signal from the Aithre Shield. Details are here https://drive.google.com/file/d/1qY-dXOeHNVgmdSXtAVRAEtdPMsJzaY4C/view

(One bit of advice...I didn't load the sensor file from Aithre, as they didn't actually have it at the time, had to email Dynon, but that aside, I simply downloaded the existing file from the EFIS, edited it to add the new sensor definition for the CO monitor, and then uploaded the modified file; I wanted to be sure that everything else was untouched).
 
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It's not a network device; it gets one of the pins on the EMS (I'll have to look at my schematics to see which one I used). Dynon has instructions on pin-out and widget configuration. Easy-peasy.

ETA: Just checked... +5V and GND using the same source from the EMS that is used for A/P servos, and I used pin 23 for signal from the Aithre Shield. Details are here https://drive.google.com/file/d/1qY-dXOeHNVgmdSXtAVRAEtdPMsJzaY4C/view

(One bit of advice...I didn't load the sensor file from Aithre, as they didn't actually have it at the time, had to email Dynon, but that aside, I simply downloaded the existing file from the EFIS, edited it to add the new sensor definition for the CO monitor, and then uploaded the modified file; I wanted to be sure that everything else was untouched).

I appreciate the info…the Aithre Shield looks to be a convenient addition.Where on your EFIS does the CO level display?

Actually, I have an AFS 5400 EFIS. It does use a Skyview Network and Dynon’s SV-200 EMS but the EFIS itself is different (pin outs for widgets is not mentioned much in the install manual). I’ve yet to talk to Aithre, about pins and configuration, but preliminarily it looks like Pin 1 off the EMS is where the signal is recommended. I wonder if I could reconfigure and use Pin 12 (coolant temp) instead.

Pin 1 Volts 1
Pin 18 Sensor 5V
Pin 17 Sensor Gnd (or any other SV-EMS ground 3, 5, 13, 16, 17, 30)
 
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I appreciate the info…the Aithre Shield looks to be a convenient addition.Where on your EFIS does the CO level display?

Actually, I have an AFS 5400 EFIS. It does use a Skyview Network and Dynon’s SV-200 EMS but the EFIS itself is different (pin outs for widgets is not mentioned much in the install manual). I’ve yet to talk to Aithre, about pins and configuration, but preliminarily it looks like Pin 1 off the EMS is where the signal is recommended. I wonder if I could reconfigure and use Pin 12 (coolant temp) instead.

Pin 1 Volts 1
Pin 18 Sensor 5V
Pin 17 Sensor Gnd (or any other SV-EMS ground 3, 5, 13, 16, 17, 30)

See pp. 6ff in the installation manual, available on-line.
 
See pp. 6ff in the installation manual, available on-line.

Thank you. The Advanced Flight 5000-series implementation of the SV-EMS 220 is different than Dynon's and the Dynon install manual (can't find page 6ff in either the AFS or Dynon manual) doesn't appear to be relevant to my installation. In the upgrade from my 4500 EFIS to the 5400 EFIS, I became intimately familiar with every frickin' DB pin in the system. I think that your Dynon pin-out scheme is likely different than my Advanced Flight version. That said...I'm pretty confident that between Aithre and AFS...I can get the info I need. I do appreciate your help.
 
Thank you. The Advanced Flight 5000-series implementation of the SV-EMS 220 is different than Dynon's and the Dynon install manual (can't find page 6ff in either the AFS or Dynon manual) doesn't appear to be relevant to my installation. In the upgrade from my 4500 EFIS to the 5400 EFIS, I became intimately familiar with every frickin' DB pin in the system. I think that your Dynon pin-out scheme is likely different than my Advanced Flight version. That said...I'm pretty confident that between Aithre and AFS...I can get the info I need. I do appreciate your help.

Not the AFS or Dynon manuals. The Aithre manuals.

https://aithreaviation.com/pages/resources
 
Ah....

ETA: Thanks. Looks pretty straightforward.

,

For Advanced, you can use either the EX 2.0 analog output or you can use the EX 3.0-s serial version (only available through Advanced or Aithre). The difference is that the EX 3.0-s uses an RS-232 output and the EX 2.0 outputs voltage. Many Advanced owners (myself included) have very limited analog pins available. So, we worked with Advanced to provide the serial option if that is required.

-Jim Ruttler, Aithre founder
RV-10, built
 
For Advanced, you can use either the EX 2.0 analog output or you can use the EX 3.0-s serial version (only available through Advanced or Aithre). The difference is that the EX 3.0-s uses an RS-232 output and the EX 2.0 outputs voltage. Many Advanced owners (myself included) have very limited analog pins available. So, we worked with Advanced to provide the serial option if that is required.

-Jim Ruttler, Aithre founder
RV-10, built

Thank you for the input. Pin 1 is readily available so I would likely just go that route. I kind of like the Aithre concept over the Sentry because I don't always fire up the Sentry (three different devices competing for a wifi slot on my iPad) and I kind of like the under-the-panel concept of the EX 2.0. Where does CO come up for display? It appears to be the "Maintenance" button.
 
For those that are using the Forensic CO detector (or similar), what do you do with the detector after the 3 year life? Does it get pitched and need to buy a new one?
Any portable digital detectors units out there that have long life (>10 years) detectors or allow for detector replacement?

My ideal detector would be stand alone (no connection to anything to get a warning) with a 2-5 year battery life and 10 year detector life, small like <2”x2”, fast response, and around $100.
 
Thank you for the input. Pin 1 is readily available so I would likely just go that route. I kind of like the Aithre concept over the Sentry because I don't always fire up the Sentry (three different devices competing for a wifi slot on my iPad) and I kind of like the under-the-panel concept of the EX 2.0. Where does CO come up for display? It appears to be the "Maintenance" button.

Advanced displays the Aithre Carbon Monoxide output in a dedicated cabin/environmental panel from the CHECK button on the right. CO is displayed along with all other Aithre health related data available in the form of a graphical engine gauge (e.g. RPM).
 
Thanks Paul Dye, (post below), for the notice of difference between CO or carbon monoxide and CO2 or carbon dioxide. It is carbon monoxide or CO that comes from incomplete combustion of fuel in engines and what I meant to refer to.
(Maybe because I was an ICU nurse for nearly three decades I still have CO2 on the brain.) :)

I don't currently have a CO detector but plan on getting one in the near future... Thinking of an early Christmas present for myself! :)

I have thought of what to do in the event of suspected CO contamination. The symptoms can include anything from headache, increase heart rate, sluggish feeling, fatigue. I had an exposure from leaking exhaust in a car when I was in my early 20's. Over the course of about 10 minutes, I went from feeling fine and wide awake to an EXTREMELY tired feeling and yawning. I stopped, got out and within a few minutes felt fine again.

Here's my self-made checklist to deal with suspected CO poisoning. Would be interested in others as well.

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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I don't currently have a CO2 detector but plan on getting one in the near future... Thinking of an early Christmas present for myself! :)

I have thought of what to do in the event of suspected CO2 contamination. The symptoms can include anything from headache, increase heart rate, sluggish feeling, fatigue. I had an exposure from leaking exhaust in a car when I was in my early 20's. Over the course of about 10 minutes, I went from feeling fine and wide awake to an EXTREMELY tired feeling and yawning. I stopped, got out and within a few minutes felt fine again.

Here's my self-made checklist to deal with suspected CO2 poisoning. Would be interested in others as well.

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.

While I haven't studied the possible scenarios for this, I have to assume the most common by far is coming in through the heat vent. Shutting that off should eliminate it and opening the vent to push clean air towards your face should help as well. Don't bother with leaning, as CO2 is produced from combustion and is still produced in large quantities regardless of how lean you go. As long as the vent is pushing clean air towards your face in good volume, it would seem that you should be able to maintain enough CO2 free air intake to get the plane down without an engine shut down.
 
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Ya’ll do know there is a significant difference between CO and CO2, don’t you….?

Paul
 
Skyview displays the Aithre CO sensor output just fine. Needs a little software file uploaded but instructions are good. Had it now for two years and works fine.
 
Anyone have any personal experience with the Geiger ""Thin Air" portable CO detector (sold by Spruce, Sportys, etc), or any of the other key chain / portable style detectors that are now available?
 
Anyone have any personal experience with the Geiger ""Thin Air" portable CO detector (sold by Spruce, Sportys, etc), or any of the other key chain / portable style detectors that are now available?

I carry a Sensorcon AV8 for planes that don't have a built in detector and have had a good experience with it (accurately alerted to an exhaust leak and confirmed both partial and complete fix). It's nice and loud, and I like have a numeric reading available. It is a little bit bulky -- not really a keychain thing, but no problem to toss in a bag.

One of the other members of the flying club I'm in has a Toxin Sensors that changes the frequency of its beeps in relation to the levels, and he quite likes that.
 
I am curious about all the people with a build in detectors.

Currently I have a portable one which I forget half the time as I also use it in the shop and its frequently there when I need it at the airport... .

What stops me from putting a build in one in my airplane is that from what I gather they all have a fairly short shelf live (couple of years) and I don't want something else that I have to remove from the panel and send to the manufacturer every couple years. Seems expensive and something else I need to track on my annual inspection list.

Thx

Oliver
 
Mickey,
I use this same unit but leave it on all the time. The batterys normally lasts at least 8 months. Saves me from remembering to turn it on.
Keith
 
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