A Denver man was found guilty of interference with a flight crew following a three day trial.

According to court documents, Joseph Wayne Lynch II boarded a flight from Philadelphia to Denver on August 5, 2015. He had missed a connecting flight and was upgraded to first class by the airline to make up for the inconvenience.

Upon boarding, the lead flight attendant limited his alcohol due to his loud and odd behavior. He became increasingly upset when she continued to deny him further alcoholic beverages.

At numerous times during the flight Lynch placed his hand on the small of the flight attendant's back and grabbed her and kissed her neck. When told that his conduct was inappropriate he began to curse at flight attendants and other passengers.

Authorities say Lynch was so loud that the plane’s captain heard his rants in the cockpit – over radio traffic and noise cancelling headphones. Investigators say Lynch threatened to bring the plane down.

Eventually his behavior escalated to the point that the captain turned over flying duties to the first officer, locked down the cockpit and requested for law enforcement to meet them at the gate upon their arrival in Denver.

Lynch faces up to 20 years in federal prison and a fine of up to $250,000 when sentenced in May.