Pilot Jim Nougarolles wearing the Metamax portable metabolic system on take-off at Annecy, France.
What did we study and why?
It is said that paragliders crash due to ‘human factors’, poor decision-making or pilot error. However we know very little about the bodies and brains of humans making the decision and errors. So, in Phase I, we first needed to establish some foundations. We started with the body, asking:
- What happens to our heart rates and breathing during flight?
- Why are we tired after flying? How much of the exhaustion we feel is physical?
Who did we study?
We studied four groups of pilots:
Escape Paragliding’s Chris White, Coco Lami, Joshua Sanderson and I flew a total of 9.3 hours in warm, comfortable conditions during the Chabre Open, at a mean altitude of 2236 m.
Flyeo’s Malin Lobb, Jim Nougarolles and Guillaume Gensse went through the SIV motions over Lake Annecy.
Finally, with the help of Flymaster, we downloaded all 223 public tracklogs uploaded by pilots using their combined vario and heart rate monitor, the Flymaster Heart-G. We selected out the 81 flights with heart rate data of longer than 20 minutes duration to exclude top-to-bottom flights and to make the data more comparable with the other groups’ flights.
When did we do it?
Summer of 2016 and 2017.
How did we do it?
To measure heart rate and breathing, we used Hexoskins: these were base layers containing fabric stretch-electrodes that gave continuous heart rate tracings, alongside estimates of breathing rate and depth.
The Hexoskins also contained very precise three-axis accelerometers to measure G forces. For Horacio and Tom, we also used oxygen saturation probes to measure what percentage of oxygen was bound to their red blood cells during their extreme altitude flights.
The hardest part was the calculation of energy consumption in flight. We used an instrument called a Metamax, a mask that measured the quantity of oxygen moving in and out of the body with each breath. The difference between the two values was the pilot’s oxygen consumption. Because fuel in the body is ‘burnt’ with oxygen, we could then use the oxygen consumption to estimate the pilot’s energy consumption and physical effort.
We divided the results of each flight into phases for analysis. We picked two five-minute thermal climbs and two five-minute glides from each flight, avoiding the first climb after take-off or the final glide to goal. The take-off phase was defined as the five minutes following the last recorded footfall and the ‘landing phase’ was the five minutes before touchdown.
We showed that pilots had strikingly high heart rates on take off but that otherwise, paragliding was much more about mental rather than physical fitness, though G forces could be high enough to cause loss consciousness and our breathing patterns might have implications for oxygen system design. Of course, our work also had its limitations.