Journal from Qi and friends
Planes and Climate, on 50 Hours Logged


Student Pilot, ASEL
52.0 hr


Qi Linzhi

Written in

Spring 2021

I’m a plane nerd. Planes were a childhood fascination that I never got over with, and then I was lucky enough to be introduced to general aviation. Aviation’s hard dependency on fossil fuel makes it harmful to the planet.

As a forcing function to reflect on the environmental impact of my activities, I’m making myself jot down some notes after every 100 hours. Hopefully for other GA pilots and flight enthusiasts, my struggle for reconciliation is relatable.

Short run: carbon offsetting

The shortcomings of carbon offsetting deserve its own journal, but for now, fining myself for the externality of flying is the least I can do. The most consumer-friendly platform I could find for offsetting was carbonfund.org.

Lycoming POH

I/IO-360, pp. 53

My training aircraft has a Lycoming IO-360-B4A engine. According to the manufacturer, it’s rated to consume a maximum of 14.5 gallons of Avgas per hour. That is sea level, best power mixture, full throttle, and engine redlining at 2700 rpm. To get this engine output, I’d imagine you’ll have to put the plane at a nose-down attitude with full power applied, and the wings might snap off after a couple of seconds. During cruise flight, 55% power on the POH gives 6.3 gph at best economy mixture.

CO₂ Emissions by Fuel

EIA report

For offsetting purposes, I’m using 14.5 gph of Hobbs time, which translates to 266 pounds of carbon dioxide per hour. And offsetting the amount of CO₂ costs … $1.20, which is roughly 1.7% of the fuel cost at the current national average of $4.93 per gallon of 100LL. Does it feel wrong that it’s lower than the credit card transaction fee?

I’ve been finding solace in paying for twice the offsetting amount at theoretical max fuel consumption. Before going to bed every night, I tell myself that I’m flying to fight climate change.

But in all seriousness, offsetting is more about awareness than impact.

Long run: decarbonizing

What does the future look like? What are some alternatives to the gas-hungry piston and jet engines?

Pipistrel Specs

Alpha, Alpha Electro

Pipistrel produces a trainer aircraft that runs on electricity, the only aircraft certified by EASA that does not run on fossil fuel while the FAA has certified none. Pipistrel’s Alpha Electro trainer has a payload of 401 lbs and a whopping 60 minutes of endurance, or 75 nautical miles of range with a 30-minute reserve. The 270-lbs battery can be swapped in a few minutes, but it doesn’t make the plane capable of most general aviation missions. Meanwhile, Pipistrel’s Alpha trainer with the same airframe offers a 507 lbs payload with full fuel, 3.1 hours of endurance, and a 324 nm range with reserves.

To put the numbers in a grimmer context, imagine using all of Pipistrel’s payload for batteries. The drone will give us 3.2 hours of endurance and roughly 242 nm of range with reserves, still shy of its gas counterpart with a full payload. It all comes down to energy density.