It was a hot (for Canada) and sunny day. Ground temperature was 36 degrees Celcius.

I was flying a DA20-C1 with an instructor on that day. The DA20-C1 is a low wing airplane sporting a big bubble canopy that provides an expansive view outside, which is fantastic.

However, the bubble canopy’s downside is that it has a tendency to make the temperature inside the cabin rise to dangerous levels on sunny summer days. So the instructor and I were sweating profusely, and we couldn’t wait to get airborne and to climb to some cooler air at altitude.

It was also a slow day, I was bored, so we decided to verify the adiabatic lapse rate in dry air. At ground school we are told that the temperature gets roughly 3 degrees Celcius cooler for each 1000 feet of altitude. So to make a long story short, we climbed to 12,000 feet, I opened the side window and extended my hand outside, and, sure enough, little frosty flakes hit my hand. The OAT was indicating zero degrees Celcius, the freezing point. 3 degrees multiplied by 12 times a thousand feet yields zero degrees.

Satisfied that we had confirmed what was in the books, we continued to wander around in the zone and had lots of fun doing it.

Later on that flight, we also simulated an engine fire, in which we dived to extinguish it. That’s when I noticed that this maneuver could damage eardrums because of the rapid descent.