Perhaps. If the pilot knows that the ATC can see he's full of it, he might be less likely to lie.

Those who still do can be grounded and be moved into management or take up a career in politics.

I’m surprised the “fuel on board” isn’t something communicated via transponder considering previous low fuel emergencies/crashes.

It wouldn’t change anything. The line between a “mayday - fuel emergency” and any other flight waiting for a landing slot is crystal clear. Of course, in low-but-not-emergency fuel scenarios the pilots can request priority, but the ATC don’t have to oblige them.

As a rule airline pilots don't lie about this stuff. They take safety pretty seriously.

Putting a theory of "you shouldn't trust pilots" into ATC breaks the entire system.

It is a system built out of very regulated parts, very professional people, and tight controls.

Pilots are encouraged to be very forward and proactive about fuel situations because of https://en.wikipedia.org/wiki/Avianca_Flight_052

Minimum fuel requirements are calculated as "Time of fuel for cruise to certain points", which is usually good enough, but if an Airport is stupid busy, or has bad wind patterns, just a couple go-arounds will chew through your fuel way faster than the regulation expects.

Turbofan engines are also dramatically less efficient at low altitude than high altitude cruise. So holding at low altitudes because a congested airport is dealing with traffic will chew through your reserves much faster than you expect.

Ryanair flies short hops to congested airports. They will have relatively low reserves, and you should expect them to run into "Hey we are low on fuel" more often than international flights for example.

"It is a system built out of very regulated parts, very professional people, and tight controls."

Locally, this is true. Globally, not so much. I remember my friend's vivid description of a flight taken in Nepal. It was absolutely wild.

> It is a system built out of very regulated parts, very professional people, and tight controls.

also worth mentioning that most of the civil aviation regulations and SOPs regarding commercial flights are written in blood.

I mean, obviously, it's better to trust the pilots, but if they are jumping the line because "fuel low" when it's not low, well, they're not being very professional, are they?