Switzerland has placed flight restrictions on 30 single-seat F-5E Tiger fighters after airframe cracks were discovered on one of the planes.
The cracks were found during an inspection of the aircraft. One was described as serious.
"After a joint risk analysis with armasuisse and RUAG (a Swiss technical company), the Air Force has decided to take preventive measures," the government said.
Aircraft with structural cracks are excluded from flight service until repaired and aircraft that have not yet been inspected are temporarily grounded.
The government said the inspection process for each plane is about two weeks. The inspection process is expected to be completed in the second quarter of this year.
Specific details of the cracks were not given.
Switzerland said the restrictions do not apply to F-5F — double seat — aircraft flown by its Air Force.
The F-5 Tiger was manufactured by Northrop Corporation and first came into service with the U.S. military in 1962.
