On the ground … finally. We’d been dodging buildups all morning over the Alps on our flight from Portoroz, Slovenia to Friedrichshafen, Germany. I do not like to get trapped in icy clouds over high terrain, so we climbed as much as we could to stay above it, eventually being at FL220 and still needing zigs and zags to stay out of the cumulus. It’s very common on a hot summer day in the alpine areas, even if you take off early, as we did. Flying a straight line, as originally planned, turned out to be nearly impossible.

Of course, we were on oxygen, using masks (above FL180) and relying on our large built-in oxygen tank. Still, something was wrong … I could feel it, but I didn’t know what it was. I had a headache, and a funny, itchy feeling in my hands and feet. The controller said he had called us three times, but he must have been mistaken because I hadn’t heard our call sign in a long while. I tried to find my pulse oximeter but couldn’t remember where I had placed it. I was tired.

The cloud buildup out the window and the in-cockpit weather portrays the kind of flight Timm and Gerda experienced from Portoroz, Slovenia to Friedrichshafen, Germany.

Gerda woke me up; she was the pilot flying that day. I was in the right seat working the radios and navigation. She pointed down to the oxygen hose which connects my mask to the aircraft system, and later explained that I had been sitting on the hose and created my own oxygen supply starvation. Hypoxia! After a while, I was feeling better. The headache remained for a couple of hours, but everything else was normal again. We started our descent on the northern side of the Alps and the weather improved – all was good.

Really? Had we really been well prepared for a situation like this? Some doubts remained and we remembered that we had a long-standing invitation to meet Piotr and Agata from Aero Poznan to attend their hypoxia course. Very soon after my oxygen event, we sat in the Aero Poznan full-motion SR22 simulator, learning more about hypoxia and how to survive.In general aviation, there are no existing requirements for pilots flying airplanes certified up to 25,000 feet to receive any practical training in detecting hypoxia. For airplanes flying above those levels, pilots need to obtain some theoretical and practical training to receive the Federal Aviation Administration (FAA) High Altitude Endorsement or pass its European equivalent, the High Performance Airplane course. Those trainings deal with problems related to pressurized cabins and how to don an emergency oxygen mask, or how to execute an emergency descent. During the course we learned about hypoxia symptoms – but we didn’t have the chance to experience them firsthand. That’s where Aero Poznan’s Hypoxia Awareness Training kicks in – they allow pilots to experience real hypoxia symptoms while flying in one of their simulators.

Here’s how it works:

Aero Poznan uses a device called ROBD2, an acronym for “Reduced Oxygen Breathing Device,” made by Environics®. This certified device was developed in a naval aerospace medical research laboratory. It provides an air/gas mix through a conventional oxygen mask and varies the amount of oxygen in the air provided to the pilot. It features an integrated oximeter, an oxygen content analyzer and an emergency button which would immediately deliver 100 percent oxygen, if needed. While the oxygen content is varied from sea level to altitude, a professional medical team is standing by in case of any intolerance or medical problems – which Piotr pointed out has never occurred.

The ROBD2 device enables hypoxia induction at different altitudes up to 34,000 feet. Achievable oxygen saturation levels vary from 4.4 to 21%. It includes a heart rate monitor that continuously displays a participant’s physiological data.

Timm in the SR22 simulator during the hypoxia training.

I was sitting in the left seat of Areo Poznan’s SR22 simulator, in which I had previously spent many hours with my clients in the left seat for IFR or emergency procedure training. I had never been there with an oxygen mask on my face, and especially not with the expectation to experience oxygen starvation and hypoxia. Marta Molinska and Roscislaw Stepaniuk were with me. Marta holds a Poznan University MA in psychology and is currently working on her PhD thesis in the field of cognitive science, especially spatial imagery, hypoxia, sleep deprivation and polar environment. She also heads the human lab activities at Aero Poznan, where she authored the theoretical parts of the Hypoxia Awareness Training. Before joining Aero Poznan, Roscislaw was a military pilot on the Mig-21 and F-16 fighters and commander of the 31st Tactical Air Base in Krzesiny, Poland. He brings his practical knowledge into the hypoxia training.

Marta started the training with a onehour lecture on hypoxia. Although I’m rated in pressurized airplanes as both an instructor and examiner, and teach human performance and limitations at our flight school, there were some aspects in her presentation I hadn’t thought about before. Then I was strapped into the familiar SR22 cockpit with a mask and headset, taking off from Innsbruck, Austria, surrounded by high terrain. I followed the commands Roscislaw was giving from his backstage instructor station. I was alone in the cockpit and there was nothing unusual as I departed and started my climb to altitude. I was “flying” VFR and made a couple zigzag turns to clear the fast-rising terrain. Of course, I was expecting something to happen, but so far all was good. At one point I overshot a turn and at another I did not level at the exact altitude Roscislaw gave me. But as I know, simulators are not perfect, so the reason was obvious. Still nothing happened; there was a beautiful view. I felt my heart pound faster than usual and I was getting a little headache. I hadn’t even reached 8,000 feet, so there was no reason to worry. Breathing through my mask was taking more effort than usual. For a moment, I lost situational awareness. I told myself I wasn’t so good at navigating VFR in the mountains; I was more of a flatlander.

Roscislaw called for another turn, but it seemed that he erred because that took me on a direct path into a huge mountain … then the stall warning horn went off. It looked like they were playing tricks on me in the sim – I know I’ve done that to others. I tried to lower the nose but the airplane was in a steep right turn … or was it a left? I attempted to find the “LVL” button on the autopilot – that’s what I’ve taught hundreds of times to my students in case they lost command of the aircraft. But it seemed that the button was missing … how can that be? The aircraft went into a steep spiral. I started thinking about pulling CAPS but I still had no idea what was going on. Roscislaw called out “Pull!” and I pulled on the yoke, but the aircraft was turning even faster. “Pull CAPS, CAPS, CAPS!” Roscislaw calls, and then I understood. The rest of the flight was under canopy. I was a little disappointed that the training was over so fast and that I didn’t reach the flight levels where we had planned to do the hypoxia training.

Back in the classroom, we discussed my flight in every detail, with sound and video from a GoPro camera that was used to illustrate what happened. First, the flight had been longer than I thought. Second, the ROBD2 device seemed to have worked well – only that they started my oxygen starvation at a much lower altitude than I had expected. “We needed you to be surprised,” they said. “In reality, it will be a surprise when you’re struck with hypoxia.” My thoughts went back to the scenario where I had sat on my oxygen hose, and I agreed. Reality is to expect the unexpected. The only trick they had played on me was the early start of the device – fair enough. All other misbehavior had been my own! Oh well …

My flying skills degraded significantly while I suffered from the starvation. Even worse, there were parts of the flight I do not remember at all. My communication was significantly impaired, both hearing and talking. And the “LVL” button was not the only button I was unable to find. At least twice I tried to dial a heading into the altitude bug. The “ball” was all over the place in turns. I forgot to adjust the mixture and my power settings lacked attention. But most importantly was that I had completely lost situational awareness. I do not remember where I was when Roscislaw called for CAPS. And the most sobering fact, obviously, is that the decision to pull no longer was my own. In a real scenario, I might have missed that decision as well. What an eye opener!

The other part to remember is how my body reacted. “While many people have similar symptoms,” Marta explains, “nobody reacts the same. For Piotr, as an example, itching is the first symptom.” For me, it seems to start with a headache. I know this from previous flights when I tried to save oxygen on long ferry flights. I know that my body reacts with a headache when my pulse oximeter shows 90 or less. That day, during the Hypoxia Awareness training, it was below 80 – not good, but a valuable experience.

Was it worth the effort? Absolutely! It’s a very different thing when you teach hypoxia in a classroom to students versus experiencing it firsthand. And the simulator, of course, is the safest place to experience your individual symptoms.

Give it a try, members can visit Aero Poznan to learn more – especially about yourself.

Timm Preusser is the international provost of COPA University. Based in Germany, he has served as the international director on the COPA Board twice since 2003, and for more than 10 years, he and his wife, Gerda, have organized all European CPPPs. He is an active CPPP flight and ground instructor, specializing in Cirrus transition and recurrent training in Europe.