KUSA – The Federal Aviation Administration has proposed a $474,000 civil penalty against Frontier Airlines for allegedly lacking required medical supplies on hundreds of flights last summer.

The FAA alleges that Frontier personnel installed aircraft emergency medical kits on 11 planes that lacked either injectable epinephrine or atropine in June and July of 2017.

According to the FAA, the Denver-basked airline was made aware it was operating with faulty emergency medical kits on July 10, 2017.

The next day, Frontier applied for an exemption allowing it to continue flying with those medical kits, the FAA said. That exemption was granted on September 16, 2017.

Before the exemption was granted, however, the FAA alleges that Frontier continued to operate the 11 aircrafts on revenue flights between July 11 and July 27.

In a statement to 9NEWS, Frontier said the issue was corrected within days of them becoming aware of it, and that current kits are fully compliant:

“There was a national shortage of certain medication in 2017 and Frontier was supplied with medical kits that were not clearly identified as being deficient. We corrected the issue within days, and medical kits currently in use are fully compliant. We intend to challenge the FAA’s position at an upcoming informal hearing.”