I've been talking to some of my less-frequent-flier colleagues recently, and I was surprised to find out that almost all of them believe that airlines make a frequent practice of canceling not-quite-full flights. They don't seem to think through the rescheduling havoc this can wreak.

Has anyone else found this idea prevalent out there? Other misconceptions about airline behavior?

I fly to a lot of smaller airports through ORD. People don't understand that "weather" means more than rain/snow at the origin or destination of a flight so when the GA says a flight is cancelled for weather they think it is due to no one on the flight to BFE.

In my experience though most of those flights are more full than flights on larger planes. My flight to CID on Sunday was oversold by 10.

I think the rumor that flights get cancelled due to light loads goes hand in hand with the same plane going back and forth to the same airports all day. Many people on my SYR-ORD flights thought the plane would turn around and go right back to SYR. Infrequent flyers need to justify things in a way that makes sense to them. "weather is fine here so it's not weather", "I see plenty of pilots so it's not crew" "it must be low #s on the flight...i only see 30 people in the boarding area"

Could there be a bit of truth in some cases?

For example, a heavily loaded flight has no plane because the plane has mechanical problems or is stuck at some other airport due to weather or missing crew. Then the airline takes a plane from a lightly loaded flight to fly the heavily loaded flight, resulting in the lightly loaded flight being cancelled.

The other thing is, many airlines treat non-elite passengers so poorly that many people think cynically about the airline's motives whenever there is some kind of problem.

Frankly, they treat everyone poorly, especially in cases of delays and cancellations... No wonder there are so many misconceptions!

The number one infrequent flier misconception is that full flight = all seats taken. In other words, "they said it was full and that poor guy couldn't get on, but I see all these empty seats", not realizing that weight, not seats, is the deciding factor in full.

This bites the little birds a lot - they need extra fuel for some rough weather or are carrying a bit of extra cargo so they have to take off with a few seats empty but are still technically full.