If you have upcoming flights on American and Delta Air Lines, you may be delayed. According to an article on MSNBC, both airlines has canceled dozen of flights on Thursday to inspect the wiring on some of their planes. These cancellations come on the heels from unsurmounted pressure from the Federal Aviation Administration.

Yesterday, American Airlines unexpectedly canceled 325 flights and is expected to cancel another 132 today. However, Delta has not officially announced the number of flights it was canceling on Thursday.

American said it began its inspections after an audit of the carrier by a joint team of inspectors from the Federal Aviation Administration and the airline. The inspections focus on proper spacing between two bundles of wires in the plane's auxiliary hydraulic system, and those wires must be installed exactly according to an FAA directive, American said.

American has completed inspections on 243 MD-80 aircraft, and about 45 planes "are still being worked on," Wagner said Thursday.

"We expect all but a few to be back in service by tomorrow," he said.

Delta expected heavy volumes Thursday at its hub at Hartsfield-Jackson Atlanta International Airport, spokeswoman Chris Kelly said. Both Delta and the Transportation Security Administration were bringing in extra staff to handle the crowd of travelers, she said.

Kelly said she didn't yet have estimates on how many passengers were affected by the flight cancellations.

Delta said its inspections are expected to be completed by Saturday.

The inspections come almost three weeks after the FAA ordered a check of all U.S. airlines' maintenance records. That was after controversy erupted over its handling of missed safety inspections at Dallas-based southwest airlines.