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Workers vote on Thursday on Boeing ( BA ) labor deal

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Two-thirds majority needed to strike on Friday

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New CEO Ortberg urges workers to accept the deal

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Boeing ( BA ) wrestling with production delays, mounting debt

(Adds details of talks with workers, voting, paragraphs 7, 15)

By Joe Brock, Allison Lampert and Carolina Mandl

SEATTLE, Sept 12 (Reuters) - Boeing's ( BA ) U.S. West

Coast factory workers stood in long lines to vote on Thursday on

a much-criticized new contract, some loudly calling for a

strike, piling pressure on the planemaker as it wrestles with

chronic production delays and mounting debt.

A potential strike could start on Friday, which would be a

big early blow to new CEO Kelly Ortberg, brought on last month

to restore faith in the planemaker after a door panel blew off a

near-new 737 MAX jet in mid-air in January.

Roughly 30,000 workers who produce Boeing's ( BA ) 737 MAX, 767 and

777 jets in the Seattle and Portland areas are voting on their

first full contract in 16 years.

Polling will close at 6 p.m. PT and the result will be

announced this evening, the International Association of

Machinists and Aerospace Workers (IAM) said. If a strike is

sanctioned, it could start at midnight.

The proposed deal includes a general wage increase of 25%, a

$3,000 signing bonus and a pledge to build Boeing's ( BA ) next

commercial jet in the Seattle area, provided the program is

launched within the four years of the contract.

Although the IAM leadership recommended its members accept

the deal on Sunday, some workers have responded angrily, with

many arguing for the originally demanded 40% pay rise and

lamenting the loss of an annual bonus.

On Thursday, a line of workers waiting to vote snaked along

the street outside the union's offices in Renton, the Seattle

suburb where Boeing ( BA ) makes its best-selling 737 jet. Some held

signs and others chanted "strike". All of several Boeing ( BA ) workers

who spoke to Reuters said they were voting to strike, and were

confident the bulk of union members would do the same, although

more than 20 declined to say what they planned.

Under complicated union rules

, two thirds must vote in favor of a strike for the action

to begin. With anything less than that, the contract will go

into effect.

"I'm ready to go on strike for as long as necessary to get

everything that we deserve," said Josh King, a 36-year-old

quality inspector. "Normally, a strike doesn't bring a worse

offer, it always brings a better offer."

In a sign some workers were already preparing for picket

lines, one union member left the meeting on Wednesday carrying a

placard under her arm that read: "On Strike Against Boeing."

Workers have been protesting all week in Boeing ( BA ) factories in

the Seattle area that assemble Boeing's ( BA ) MAX, 777 and 767 jets.

One member wearing a high-visibility vest shouted, "time to

strike, baby!" as he exited the building after casting his

vote.

Shares in Boeing ( BA ) were up 0.4% in afternoon trading.

ORTBERG'S PLEA

Boeing shares are down 36% this year on concerns over safety,

production and a $60 billion debt burden. A strike would pile on

the financial pain and add to delays in delivering planes to

airlines already struggling with capacity shortages.

According to a note from TD Cowen, a 50-day strike could

cost Boeing ( BA ) an estimated $3 billion to $3.5 billion of cash

flow. The Boeing ( BA ) workers' last strike in 2008 shuttered plants

for 52 days and hit revenue by an estimated $100 million per

day.

Boeing ( BA ) faces multiple challenges if there is a strike: it

will need to decide how to respond at the bargaining table,

after saying it had offered everything it could, as well as

secure factories full of extremely valuable, partially built

planes, without union workers to do the job.

S&P Global Ratings said an extended strike could delay

the planemaker's recovery and hurt its overall rating. Both S&P

and Moody's rate Boeing ( BA ) one notch above junk status.

On Wednesday, Ortberg sent a letter to workers, urging them

to approve the deal.

"A strike would put our shared recovery in jeopardy, further

eroding trust with our customers and hurting our ability to

determine our future together," the letter said.

The labor talks are a key test for Ortberg, who met with the

union's main negotiator after arriving in August with a pledge

to improve labor relations and safety and ramp up production of

Boeing's ( BA ) best-selling 737 MAX passenger jet.

Ortberg and Boeing Commercial Airplanes boss Stephanie Pope

hit the floor at the company's jet assembly plants in Everett

and Renton this week to talk with workers about the proposed

deal, a source said. Boeing ( BA ) said that the average worker pay of

$75,608 would grow to $106,350 by the end of the contract,

excluding overtime.

A strike could also become an issue for airlines which

depend on Boeing's ( BA ) aircraft. Still, Michael O'Leary, CEO of

Boeing ( BA ) customer Ryanair said on Thursday that a strike

could further delay aircraft deliveries, but added he believed

that if it happened, it would be short. "We would like to see

the labor agreement sorted," he said.

Boeing ( BA ) machine repair mechanic Harold Wilson said he had

mixed emotions about the contract and wanted to see better

pensions and higher wages for younger workers.

"I think Boeing ( BA ) will be left struggling again."