[Zaphod58]

They can’t. The USAF doesn’t have enough airlift as it is, and the -135 plays a vital role in that mission, as well as the tanker mission. With only the KC-10 to take over that would leave no tankers left to perform the mission if they grounded the -135 as a precaution.

[topher]

It is unclear if this is maintenance or terrorism.

But there was a case in the US Navy where an admiral took his carrier task force and was in a stand down mode.

There were just too many accidents (preventable accidents, that is) happening.

They straightened things out, and then went back into operation.

This admiral, I am pretty sure, became the CNO at some time after this.

I believe his name was Kelso. And I am not sure of the time frame, but it was either during the presidency's of George H. W. Bush or Bill Clinton.

[topher]

The USAF did this when it was found that there were airframe problems with F-15's because of age. They stood down all F-15's.

The USAF needs to have a backup plan -- of some sort.