June 12 The stealthy F-35 fighter jets made by
Lockheed Martin Corp remained temporarily grounded at a
U.S. Air Force base in Arizona on Monday because of
irregularities in pilots' oxygen supplies, an Air Force
Training flights were grounded on Friday and had been
scheduled to resume on Monday.
The pause in operations continued so the Air Force could
study the issue with pilots, maintenance workers and medical
professionals, the base spokeswoman said.
(Reporting by Mike Stone; Editing by Jonathan Oatis)