Paul Njoroge, representing the families of Ethiopian Airlines Flight 302, testifies before a House Transportation and Infrastructure Aviation Subcommittee hearing on "State of Aviation Safety" in the aftermath of two deadly Boeing 737 MAX crashes since October, in Washington D.C., July 17, 2019.

A man whose family was killed in the crash of a Boeing 737 Max in Ethiopia in March slammed the manufacturer and told lawmakers at a congressional hearing Wednesday to scrutinize the Federal Aviation Administration, which approved the now-grounded planes two years ago.

Paul Njoroge lost his wife, three small children and his mother-in-law on Nairobi-bound Ethiopian Airlines Flight 302, a Boeing 737 Max 8 that crashed minutes after takeoff from Addis Ababa, killing all 157 people on board. It followed the crash of another Boeing 737 Max, Lion Air Flight 610 in Indonesia, in October. All 189 people on that flight were killed.

The twin crashes prompted aviation officials around the world to ground the jets in mid-March. Investigators have implicated an anti-stall system in both crashes. Boeing has developed a fix for the software to make it less aggressive and give pilots greater control of the aircraft, a newer version of Boeing's workhorse 737 that's been flying since the 1960s. Regulators have not said when they will allow the planes to fly again.

The House aviation panel is hearing from Njoroge as well as well as union officials representing pilots, mechanics and flight attendants at its third hearing on the 737 Max crashes.

"I miss their laughter, their playfulness, their touch," Njoroge said of his family in written testimony. "I am empty. I feel that I should have been on that plane with them. My life has no meaning. It is difficult for me to think of anything else but the horror they must have felt."

Lawmakers have not yet questioned Boeing officials, engineers or whistleblowers, and Njoroge urged the House panel to do so.