Traveling in large groups is uncomfortable for many reasons: cramped spaces, unfriendly service, and lousy food. Everyone has their pet peeves.
But regardless of whether you are in business class or coach, where some incriminating circumstances can be alleviated, temperature and humidity are the best indicators of how pleasant a flight will be. So, I bought a temperature and humidity gauge and measured boarding and cruising altitude temperatures on some of my recent flights.

Temperatures above 80F are considered uncomfortable, and your car’s default temperature position is set to 72F. The chart below shows that the temperature on some Delta flights is out of control, but many other airlines appear to struggle or care less about maintaining healthy comfort levels.
We’ll keep aggregating and reposting as we fly those “friendly skies.” Based on those aggregates, we will decide what to fly next.