Originally Posted by
apodo77
The last time I flew WN (3x in 2017) there was actually empty bin space and a breeze to carry on. Same for Frontier in 2016 (flew twice). All just anecdotal evidence of course.
One thing is certain in my 275+ segments the past 2.75 years on DL is that OHB runs out on almost every flight I have been on including me having to check my bag when connections are running late (even in F twice).
Business heavy routes on Southwest will also fill up, but in general the OHB do fill up less quickly (in my experience). All anecdotal, but one of the big benefits to Southwest of free checked bags is that it speeds up their turn time for the very reason that people are (on average) less likely to fight over OHB space meaning boarding is faster.
Delta flights (and quite frankly legacy carrier flights in general) are slowed down by the fight for OHB space. There's a reason Delta earmarks a ridiculous 40 minutes for boarding - once you take into account Delta's inefficient boarding order (which in fairness is mostly matched by other legacy's bad boarding process) and the inevitable "out of OHB space" shuffle at the end it often does take 35-40 minutes on a 739 or 752/3 whereas Southwest can reliably get people on board and seated in 15 minutes.