WASHINGTON, March 11 (Reuters) - U.S. Transportation

Secretary Pete Buttigieg said on Monday he expected Boeing ( BA )

to cooperate in investigations by the Justice Department

and National Transportation Safety Board into the Alaska

Airlines 737 MAX 9 mid-air emergency on Jan. 5.

"We respect the independence of DOJ and NTSB doing their own

work, but we're not neutral on the question of whether Boeing ( BA )

should fully cooperate with any entity - NTSB, us or DOJ. And

they should, and we expect them to," Buttigieg told a press

conference.

He said Federal Aviation Administration chief Michael

Whitaker had made clear to Boeing ( BA ) that "they need to go through

a serious transformation here in terms of their responsiveness,

their culture and their quality issues."

Boeing ( BA ) said in response it "will continue to cooperate fully

and transparently with all government investigations and audits,

as we take comprehensive action to improve safety and quality."

Boeing ( BA ) shares closed down 3%.

The aircraft manufacturer said on Friday it believed during

production of the Alaska Airlines MAX 9, required documents were

never created that should have detailed the removal of the door

plug that failed, resulting in a mid-air emergency.

Alaska Airlines said on Saturday it was "fully

cooperating" with the Justice Department in its criminal

investigation and it did not believe it was a target of the

probe.

In the aftermath of the incident, the FAA grounded the MAX 9

for several weeks, barred Boeing ( BA ) from increasing the MAX

production rate and ordered it to develop a comprehensive plan

to address "systemic quality-control issues" within 90 days.

NTSB Chair Jennifer Homendy last week criticized what she

termed Boeing's ( BA ) lack of cooperation and failure to disclose some

documents, including on the door plug opening and closing, as

well as the names of 25 workers on the door crew at the 737

factory in Renton, Washington.

"It is absurd that two months later we don't have it,"

Homendy said.

After Homendy's comments, Boeing ( BA ) provided the 25 names and

said the NTSB had only sought the names on Saturday. She plans

to send a letter to the Senate later this week detailing

Boeing's ( BA ) cooperation to date.

The FAA's Whitaker said on Monday the agency and Boeing ( BA ) hope

to define in the next 30 days the milestones the manufacturer

must meet in order to increase the MAX production rate.

An FAA audit released last week found issues with Boeing's ( BA )

manufacturing process control, parts handling and storage, and

product control.

"We're really focused on quality assurance process where

there really are gaps," Whitaker said, citing issues like

"having the employees have the right tools and training, having

the right engineering drawings, and assembling the aircraft in

the proper order."