A federal probe into how an air traffic controller’s error put two jets in danger of colliding over Hawaii shows the worker didn’t believe he was ready to direct aircraft from the radar station where he was assigned and had asked for more training.

The incident involved a Japan Airlines flight from Tokyo and a United Parcel Service flight from Louisville, Ky., as they approached Hono­lulu Airport on Jan. 14. Federal Aviation Administration investigation documents obtained through the Freedom of Information Act show the jets came within 300 feet of each other vertically and less than two miles horizontally before changing course to avoid getting too close.

FAA rules required the planes to be separated by at least 1,000 feet vertically or three miles horizontally.

The agency said it acted swiftly once it learned of the incident, took the controller off operational duties and gave him additional training.

"The FAA is committed to ensuring the safety of our nation’s airspace for the traveling public, and we take seriously and investigate all reported infractions," the agency said in a statement.

The incident and investigation were first reported by Hawaii News Now.

The controller had a little more than two years’ experience with air traffic control, an FAA memo said. He earned certification to operate the radar station he was manning Dec. 24 — a few weeks before the incident — but said he didn’t feel adequately prepared for the job.