Captain Stephen Wearing, who has flown for BA for 29 years, described what greeted him when he flew into Heathrow at the weekend as "the worst chaos I've ever seen".
He called the situation "unbelievable" and said he'd had to drive a cancer-stricken passenger home from Heathrow after a delay of nearly four hours on the tarmac left the elderly man stranded.
The problems continued with delays at Gatwick and mass cancellations of short-haul flights from Heathrow.
Some passengers were not offered free food or water on the planes, and most left London's airports without luggage they had checked in, only to find hotels' "surge" pricing put rooms at more than £1000 per night.
Passengers vented their fury at BA online, after little or no information was provided at airports.
Laura Thomson and Sam Sciortino, from Woking in Surrey, were forced to postpone their Greek island wedding after their bridesmaids were grounded at Heathrow.
Marcia Thomson, Laura's sister-in law and bridesmaid, said: "You couldn't make it up. I am just a shell of myself right now. We are absolutely shattered".
Experts believe BA will face compensation payouts in excess of £50 million but stands to lose the same again in goodwill payments and lost custom.
The company's new chief executive was under fire, with questions asked as to his suitability for the role after a career in low-cost airlines.
Many of the airlines' IT systems had been recovered but BA warned passengers not to arrive at Heathrow today until 90 minutes prior to their scheduled departure time.