(CNN) -- A nuclear missile base in Montana that failed a safety test this month has let its security chief go.
The 341st Missile Wing at Malmstrom Air Force Base operates about a third of the nation's Minuteman III nuclear missiles.
It did not relieve Col. David Lynch from his command over the security forces group because of the failure, the base said in a statement released this week. But missile wing commander, Col. Robert Stanley, will feel more confident about passing the next inspection without him.
Lynch led four squadrons and more than 1,200 people, whose duty it is to secure and protect the missile wing, which controls 150 long-range nuclear missile silos.
The 341st was the second nuclear missile wing to stumble over a safety and security inspection this year.
It received an "unsatisfactory rating" after making "tactical level errors" during one of several exercises conducted as part of the inspection.
The errors were not related to the operation of nuclear missiles, one Air Force official said. The precise issue was not disclosed.
The wing, which includes about 3,000 personnel in total, was not "decertified" to conduct nuclear operations, which would have indicated a more significant failure.
Earlier this year, another wing, based at Minot, North Dakota, did poorly in an inspection, resulting in the removal of 17 military personnel from their jobs.
A third missile wing is located at F.E. Warren Air Force Base in Wyoming.
CNN's Amanda Watts contributed to this report