Mountain High Cannula/Mask?

Does everyone stick to the 18k limit for the cannula and 25k for the mask,

or are these limits considered advisory only?

I use the blue mask if I'm planning to go above 18k and have been above 27k with no issues. (It is an unhelpful fire drill at 17k changing systems in a cockpit, so if you plan to go high, just start with the mask. You can fit it on the ground and hang it from the neck strap. Then pull the top strap back over the head when you get above 10k if you wish.)

It's not clear to me the regs or the physiology eliminate the cannula above 18k if you can remember to use your nose, but the mask covers the bases and looks cool in those wave picts.

What works can vary widely depending on the person, so pulse oximeter is useful to verify things are working. (A brain in la-la land is not dependable to do this on it's own. Especially in and above the 20's.)

Dress warm now...

On Tuesday, October 1, 2019 at 6:45:06 AM UTC-4, John McLaughlin wrote:
Does everyone stick to the 18k limit for the cannula and 25k for the mask,

or are these limits considered advisory only?

The legalitys are not so clear, but practically it is about remembering to breathe only with your nose with the cannula. Something I felt i could do, and so far have remembered. It is much easier to hydrate and communicate with the cannula. Just don't forget...

RR

Non smoker, rather active, good health.....may be fine.
Couch potato, smoker, heart issues, etc., may be in bad shape walking in Denver, let alone flying higher....yes, I have had to run through the Denver airport from a late flight trying to catch a connecting flight.....sucked carrying a heavy bag...
YMMV......

Yes, finger probe (I believe under $100US) will basically tell you how you're doing on O2.

On Tuesday, October 1, 2019 at 6:16:30 PM UTC-4, Charlie M. (UH & 002 owner/pilot) wrote:
Non smoker, rather active, good health.....may be fine.
Couch potato, smoker, heart issues, etc., may be in bad shape walking in Denver, let alone flying higher....yes, I have had to run through the Denver airport from a late flight trying to catch a connecting flight.....sucked carrying a heavy bag...
YMMV......

Yes, finger probe (I believe under $100US) will basically tell you how you're doing on O2.

Unless you hyperventilate. What happens then?

T8

On Tuesday, October 1, 2019 at 3:44:11 PM UTC-4, RR wrote:
On Tuesday, October 1, 2019 at 6:45:06 AM UTC-4, John McLaughlin wrote:
Does everyone stick to the 18k limit for the cannula and 25k for the mask,

or are these limits considered advisory only?

The legalitys are not so clear, but practically it is about remembering to breathe only with your nose with the cannula. Something I felt i could do, and so far have remembered. It is much easier to hydrate and communicate with the cannula. Just don't forget...

RR

There are several reasons any given person might not breathe well on a cannula at high altitude, mouth breathing is only one. Here's another: It is really easy to hyperventilate on a cannula at 20+K. Trivially easy in fact.. If you must use a cannula above 18K (which I recommend against), do not skimp on the O2, don't use a dumb ass "oxy-miser" anything above 18K. Turn up the flow. If in doubt, turn it up some more. Not a bad idea to monitor heart rate as well as O2 saturation. Tachycardia is reliable indicator of breathing problems, and it will catch hyperventilation (O2 saturation will not, key word alkalosis).

It's much easier to breathe well (and reliably) on a mask, provided the mask fits and seals acceptably well. If you aren't breathing well, hydration and communication are going to cease to matter.

T8

On Tuesday, October 1, 2019 at 3:16:30 PM UTC-7, Charlie M. (UH & 002 owner/pilot) wrote:
Non smoker, rather active, good health.....may be fine.
Couch potato, smoker, heart issues, etc., may be in bad shape walking in Denver, let alone flying higher....yes, I have had to run through the Denver airport from a late flight trying to catch a connecting flight.....sucked carrying a heavy bag...
YMMV......

Yes, finger probe (I believe under $100US) will basically tell you how you're doing on O2.

You can get them for $15 now, and better ones for $25.

According to tests, even the cheapest are accurate, it just comes down to build quality and extra features e.g. nice graph of your pulse depth (and numerical assessment of that), BlueTooth connection to your phone etc.

I just got an "Innovo Deluxe Fingertip Pulse Oximeter with Plethysmograph and Perfusion Index" for $26.99. I haven't used it in anger yet, but I'm planning to see what it says on my 12 hour flight from SFO to AKL tonight :-) It seems good so far.

https://www.amazon.com/gp/product/B0..._title_o00_s00

On Tuesday, October 1, 2019 at 5:12:51 PM UTC-7, Bruce Hoult wrote:
On Tuesday, October 1, 2019 at 3:16:30 PM UTC-7, Charlie M. (UH & 002 owner/pilot) wrote:
Non smoker, rather active, good health.....may be fine.
Couch potato, smoker, heart issues, etc., may be in bad shape walking in Denver, let alone flying higher....yes, I have had to run through the Denver airport from a late flight trying to catch a connecting flight.....sucked carrying a heavy bag...
YMMV......

Yes, finger probe (I believe under $100US) will basically tell you how you're doing on O2.

You can get them for $15 now, and better ones for $25.

According to tests, even the cheapest are accurate, it just comes down to build quality and extra features e.g. nice graph of your pulse depth (and numerical assessment of that), BlueTooth connection to your phone etc.

I just got an "Innovo Deluxe Fingertip Pulse Oximeter with Plethysmograph and Perfusion Index" for $26.99. I haven't used it in anger yet, but I'm planning to see what it says on my 12 hour flight from SFO to AKL tonight :-) It seems good so far.

https://www.amazon.com/gp/product/B0..._title_o00_s00

My Sansung Galaxy S8 phone with the Samsung Health app has a pulse oximeter.

Richard
www.craggyaero.com

On Tuesday, October 1, 2019 at 3:44:11 PM UTC-4, RR wrote:

The legalitys are not so clear [...]

FAR 23.1447 spells it out (for certificated aircraft). Above 18K the requirement is for a mask that covers nose and mouth.

The fact that some people can get away with a cannula at 26K (once) does not mean that this is a sound practice. We've had two hypoxia incidents (that I know of) at Mt Washington due to pilots emulating certain old timers. Physiology varies. Physical fitness doesn't seem to be a factor (in fact casual observation suggests the reverse :-)).

T8

RR wrote on 10/1/2019 12:44 PM:
On Tuesday, October 1, 2019 at 6:45:06 AM UTC-4, John McLaughlin wrote:
Does everyone stick to the 18k limit for the cannula and 25k for the mask,

or are these limits considered advisory only?

The legalitys are not so clear, but practically it is about remembering to breathe only with your nose with the cannula. Something I felt i could do, and so far have remembered. It is much easier to hydrate and communicate with the cannula. Just don't forget...

The Mountain high EDS units will alarm if you don't breathe frequently enough, so
that might be sufficient to remind pilots to breather through their nose.
Continuous use of an oximeter that alarms with a low SPO2% may be a useful
additional reminder to breathe properly, and I think I would use one even if I was
using a mask.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1