American Airlines (AA, Dallas/Fort Worth) has joined Southwest Airlines (WN, Dallas Love Field) in announcing that it has now cancelled all B737-8 flights up to August 2019. The two airlines combined cancelled approximately 275 flights per day as a result of the type's grounding, Seeking Alpha has reported.

While Boeing (BOE, Washington National) is working on certifying a software fix to its Maneuvering Characteristics Augmentation System (MCAS), operators around the world are forced to either cancel flights, defer the retirement of older aircraft the MAX aircraft were due to replace, or wet-lease in capacity from other carriers.

Being slightly more optimistic, United Airlines (UA, Chicago O'Hare) has removed its fourteen B737-9s from the schedule until early July. Chief Financial Officer Gerald Laderman reassured investors in the company's Q1 earnings call that United also still expects delivery of another sixteen aircraft of the type later this year, despite the current grounding.

American currently has twenty-four B737-8s in its fleet, while Southwest is the type's largest operator with thirty-four aircraft.