UPDATE 3-U.S. FAA chief tests Boeing 737 MAX in certification step

(Adds statement from crash victim's father, paragraph 10-11)

By Eric M. Johnson and David Shepardson

SEATTLE/WASHINGTON, Sept 30 (Reuters) - Federal Aviation Administration (FAA) Chief Steve Dickson conducted a nearly two-hour evaluation flight at the controls of a Boeing 737 MAX on Wednesday, a milestone for the jet to win approval to resume flying after two fatal crashes.

Dickson, a former military and commercial pilot, and other FAA and Boeing pilots landed shortly before 11 a.m. local time (1800 GMT) at King County International Airport - also known as Boeing Field - in the Seattle area.

Dickson is set to host a news conference following the flight.

The flight is a key part of the U.S. planemaker's long-delayed quest to persuade the FAA to lift a March 2019 grounding order triggered by 737 MAX crashes in Ethiopia and Indonesia that killed 346 people within a five-month period.

The accidents plunged Boeing into its worst-ever crisis, strained its relationship with the FAA, threw into question the U.S. regulator's position as the standard-bearer for global aviation safety and prompted bipartisan calls in Congress to overhaul how the FAA certifies new airplanes.

Dickson has repeatedly said he would not sign off until he flew it himself and was "satisfied that I would put my own family on it without a second thought."

Dickson tested a number of Boeing design and operations upgrades intended to prevent similar disasters. In both crashes, a flawed control system known as MCAS, triggered by faulty data from a single airflow sensor, repeatedly and forcefully pushed down the jet's nose as pilots struggled to intervene.

If Dickson's flight and broader reviews go well, the FAA is seen as likely to lift its U.S. grounding order in late November, industry sources said, putting the MAX on a path to resume commercial service potentially before year-end.

That timeline jibes with comments last week from Dickson's counterpart in Europe, Patrick Ky. He said the European Union Aviation Safety Agency (EASA) expects to lift its technical ban "not long" after the FAA, but national operational clearances needed for individual airlines to resume flying could take longer.

Michael Stumo, whose daughter was among the 157 people killed in the second 737 MAX crash, again called on the FAA and Boeing to provide the technical descriptions and test data that they are relying upon to recertify the plane.

"Without that secret data, independent experts and the public cannot confirm whether the aircraft is safe," Stumo said.

Separately, the U.S. House Committee on Transportation and Infrastructure on Wednesday unanimously approved bipartisan legislation to reform the FAA's aircraft certification process in the wake of the 737 MAX crashes. (Reporting by Eric M. Johnson in Seattle and David Shepardson in Washington; additional reporting by Tracy Rucinski in Chicago; editing by David Gregorio and Steve Orlofsky)