Fast n' Furious
Line Up and Wait
I attended my every four year mandatory physiological training a couple of weeks back. Part of that is the altitude chamber exercise. As most of the folks on this site might never have been exposed to this sort of training, I thought I'd give an overview on what it's all about.
First, the ground school. Everything you wanted to know about flight physiology, respiration, oxygen systems, common flight medicine issues and the chamber briefing.
The ride itself. Started off with an equipment check of the mask, the oxygen hookup, and the communication system. Pretty standard stuff although the mask used in the chamber is a bit different than the quick donning masks we use in the airplane.
To ensure that you don't have any sinus issues you get a quick bounce from sea level to 6000 feet and then right back down. If all is well, the mask goes on and you do a twenty minute pure oxygen saturation to get your level up and get as much nitrogen out of your system as possible. Then the mask comes off and it's time to take the rapid decompression exercise.
The instructor will climb the cabin at about 1000 feet per minute to about 10000 feet and then you'll expereince the "rapid D". As the cabin climbs to 18000 in a couple of seconds, fog will form and the temperature will drop noticably. That is also your cue to put the mask back on and select 100 percent oxygen.
Once that exercise is stabilized it's time to climb to 25000 for the hypoxia exercise. This is always fun. Off comes the mask and my first task is to write my name on the worksheet and then do five easy math problems consisting of simple addition and subtraction. I get these done in a minute and then I'm asked to write down any symptom of hypoxia that I'm expereincing. Nothing so far and my oxygen saturation is good at 94%.
During the second minute I start tracing my way through a maze drawn on the worksheet. Things go well and at the end of the second minute my oxygen saturation is about 80% and my right arm is a bit tingly. Still good to go as I could put my mask on immediately if I needed to.
Minute three has me looking at an approach plate and a color wheel. The colors are muddy and the words and numbers are getting tough to read. My head is getting light, my arm still tingles but other than that, I don't feel too bad. Again, if I really needed to put my mask on, it wouldn't be a struggle. My oxygen saturation level though has dropped to 65% and it's now dropping like a greased brick.
I got my third and final symptom of hypoxia at about four minutes and fifteen seconds which was a general tightening of my chest. My saturation was below 50% and while I put my mask on unassisted, it wouldn't have been too much longer before I would have needed help. Assuming there was help available. B)
It took a while to get my saturation level back up once the mask went back on and I used that time to note how my vision improved. The approach plate was now easily readable and the colors on the wheel were vivid and sharp when just a few minutes before looked like shades of grey.
Exercise over, down we go go back to sea level in a steady descent but at good rate.
I was happy to note that my known symptoms of hypoxia really haven't changed since my baseline flight years back. I would recommend the expereince to everyone.
First, the ground school. Everything you wanted to know about flight physiology, respiration, oxygen systems, common flight medicine issues and the chamber briefing.
The ride itself. Started off with an equipment check of the mask, the oxygen hookup, and the communication system. Pretty standard stuff although the mask used in the chamber is a bit different than the quick donning masks we use in the airplane.
To ensure that you don't have any sinus issues you get a quick bounce from sea level to 6000 feet and then right back down. If all is well, the mask goes on and you do a twenty minute pure oxygen saturation to get your level up and get as much nitrogen out of your system as possible. Then the mask comes off and it's time to take the rapid decompression exercise.
The instructor will climb the cabin at about 1000 feet per minute to about 10000 feet and then you'll expereince the "rapid D". As the cabin climbs to 18000 in a couple of seconds, fog will form and the temperature will drop noticably. That is also your cue to put the mask back on and select 100 percent oxygen.
Once that exercise is stabilized it's time to climb to 25000 for the hypoxia exercise. This is always fun. Off comes the mask and my first task is to write my name on the worksheet and then do five easy math problems consisting of simple addition and subtraction. I get these done in a minute and then I'm asked to write down any symptom of hypoxia that I'm expereincing. Nothing so far and my oxygen saturation is good at 94%.
During the second minute I start tracing my way through a maze drawn on the worksheet. Things go well and at the end of the second minute my oxygen saturation is about 80% and my right arm is a bit tingly. Still good to go as I could put my mask on immediately if I needed to.
Minute three has me looking at an approach plate and a color wheel. The colors are muddy and the words and numbers are getting tough to read. My head is getting light, my arm still tingles but other than that, I don't feel too bad. Again, if I really needed to put my mask on, it wouldn't be a struggle. My oxygen saturation level though has dropped to 65% and it's now dropping like a greased brick.
I got my third and final symptom of hypoxia at about four minutes and fifteen seconds which was a general tightening of my chest. My saturation was below 50% and while I put my mask on unassisted, it wouldn't have been too much longer before I would have needed help. Assuming there was help available. B)
It took a while to get my saturation level back up once the mask went back on and I used that time to note how my vision improved. The approach plate was now easily readable and the colors on the wheel were vivid and sharp when just a few minutes before looked like shades of grey.
Exercise over, down we go go back to sea level in a steady descent but at good rate.
I was happy to note that my known symptoms of hypoxia really haven't changed since my baseline flight years back. I would recommend the expereince to everyone.
