All the while, company owner Daniel Stegeman said, Levitt was flying "off and on" for the business, ferrying aircraft from its Chester County headquarters to points of sale across the Northeast.
Hours before he landed in handcuffs, Levitt had supervised a flight between West Chester and Rhode Island, Stegeman said.
"I'm not entirely sure what to say," Stegeman said Tuesday. "I had no idea. I'm a tiny guy with a tiny company who was trying to help out a guy."
Levitt, who was released on $250,000 bail Monday, could not be reached for comment.
FAA regulations require preflight drug tests only for pilots with large commercial airlines. DCS Aviation would not necessarily be required to regularly test its pilots, said Jim Peters, an agency spokesman.
Pilots under 40 are, however, required to receive medical evaluations every four years and sign a document professing they are not addicted to alcohol or drugs, Peters said.
How long Levitt, a former Navy pilot, had held his general aviation license remained unclear Tuesday, as did the last time he was evaluated by a doctor.
No one was injured by the shot Levitt allegedly fired just before midnight Saturday from his .40-caliber Sig Sauer Elite. The bullet went through two neighboring apartments before becoming lodged in an upstairs neighbor's floor.
When township police responded to Levitt's apartment near the intersection of Route 1 and I-95 in Langhorne on Friday, he told them that he had been sleeping with the gun under his pillow and that it must have gone off when he had a bad dream.
Officers questioned the story after finding drug paraphernalia in the apartment, including packets decorated with images of skulls and crossbones, and automatic weapons, according to court filings.
Levitt initially said that the drugs probably belonged to a relative who stayed with him during Hurricane Sandy, according to the probable cause affidavit filed for his arrest. He later admitted his addiction, investigators said, but maintained that he had not intentionally fired the weapon.
Detectives also found literature from a drug rehab facility in the apartment.
While Stegeman said Tuesday that he had heard of Levitt's arrest, he was not aware that the pilot had purportedly admitted to repeated drug use.
"He came highly recommended to us," the business owner said. "We tested him for his skills. But we do not do drug testing."
He added: "He's not going to be flying for us again."
Levitt faces charges of drug possession, reckless endangerment, and discharging a firearm into an occupied structure. He is scheduled to appear for a preliminary hearing Thursday.
Contact Jeremy Roebuck at 267-564-5218, firstname.lastname@example.org, or @jeremyrroebuck on Twitter.