The FAA changed the standard average passenger / bag weights this summer. Delta implemented the changeover on August 31. Drumroll ... you all got fatter Everyone magically weighs 15 lbs heavier than they did a month ago, at least in the eyes of the Feds. Standard checked bag, and heavy bag weights increased, too.

this is effective across all fleets, but on average, this equates to about 3,000 extra lbs on a B738 or A320, and about 6,000 extra lbs on an A330 that gets lugged around. The A220s and A320s are particularly sensitive as they are usually up against max structural landing weight if you have a full passenger load and need to carry an alternate for dispatch.

You would think this is the case, but its not how the FAA computes things for weight and balance. Those bags in the overhead bins are INCLUDED in your average passenger weight. The minute they need to be gate checked, its an extra 35 lbs per bag hit on the payload. The gate agents know the flight is Payload Optimized and will try extra hard to not have to gate-check bags. If the FAs close the bins early when they aren't really "full" you'll be leaving standbys at the gate in favor of "weight" that has to be added to the belly as gate-checked bags (even though those bags were going to be on the airplane regardless).