Airlines struggling to staff their planes have cancelled or delayed thousands of US flights over the long <a href="https://www.thenationalnews.com/world/us-news/2022/06/30/is-july-4-a-federal-holiday-in-the-usa/" target="_blank">July 4 holiday weekend.</a> As of Sunday morning, with Americans gearing up for Independence Day celebrations on Monday, more than 1,297 flights within, into, or out of the US had been cancelled, and more than 11,730 were delayed, according to flight tracking service<a href="https://flightaware.com/live/cancelled" target="_blank"> flightaware.com.</a> The numbers on Friday and Saturday were grim as well, with thousands more flights cancelled or delayed. The airport chaos is prompting a record level of road travel by Americans seeking to dodge flight trouble, a travel industry group said. For days, amid a surge in travel as summer rolls in, horror stories have abounded as travellers have been stranded at airports, unable to reach their destinations. The airline industry was devastated in the early stages of the Covid-19 pandemic as people stayed close to home, but air travel has rebounded as health measures have eased. Although federal Covid-19 relief spared airlines from laying off staff, tens of thousands of workers left the industry after carriers urged early retirement. Today's industry has about 15 per cent fewer staff compared with the pre-pandemic period to handle about 90 per cent of pre-2020 passenger volume, analysts at Third Bridge consultancy estimated. The travel chaos has drawn scrutiny from Transportation Secretary Pete Buttigieg and others in Washington. On Saturday, Mr Buttigieg tweeted a series of tips on what to do if one's flight is cancelled, such as whether to accept travel points or miles as compensation, or demand a cash refund. "You can often negotiate on this. That's between you and the airline," Mr Buttigieg wrote. The travel season is at full speed, with 2,490,490 people screened at airport checkpoints nationwide on Friday, the most since February 2020, just before the Covid shutdown in the US, the Transportation Security Administration said. "We are back to pre-pandemic checkpoint volume," the TSA tweeted. Delta pilots walked along informational picket lines at several airports on Thursday to demand a new contract and complain of overwork, among other issues. "Quite frankly, it's irresponsible scheduling, over scheduling. Coming out of the pandemic, we're scheduling more flights than we have people to fly them," Delta pilots association union leader Jason Ambrosi told CNN on Saturday. <i>- AFP contributed to this report</i>