saying pilots are so exhausted, it s the company s number one safety threat. in a statement, southwest saying weather and airspace delays led to fatigue in march, and that calls from pilots too tired to fly are a result of the system working as designed. this is the industry certainly paying a price for perhaps underestimating how quickly travel would rebound after covid. reporter: and now, with the ba.2 subvariant fueling a fresh covid wave, federal officials this week extending the transportation mask mandate until at least may 3rd. new cases and hospital admissions now up 10% or more in many parts of the country. once something becomes dominant, usually about a week or ten days later, you start getting a pretty good sense of what s happening with hospitalization. certainly by two weeks, i think we ll have a much clearer picture. reporter: keep in mind, on average, more than 2 million people are already screened at