AUSTIN, Texas -- Investigators say the pilot of a Texas hot air balloon that crashed and killed 16 people flew with enough Benadryl in his system to have the equivalent blood-alcohol level of a drunken driver.

National Transportation Safety Board investigators said Tuesday at a hearing in Washington that pilot Alfred “Skip'' Nichols also took sedatives and opioids that likely affected his decision-making during the July 2016 flight.

The balloon hit high-tension power lines before crashing into a pasture near Austin. It was the worst hot-air balloon disaster in U.S. history. Investigators say Nichols was told during a weather briefing before the flight that clouds may be a problem. But he allegedly replied, "we just fly in between them.''

Nichols had at least four convictions for drunken driving and twice spent time in prison. Texas Republican John Cyrier, whose district includes the crash site, thinks the NTSB will recommend that commercial hot air balloon pilots get the same medical screenings as those flying planes or helicopters.

The Federal Aviation Administration must ultimately approve any new oversight.