Sept 13 (Reuters) - A strike beginning Friday by more

than 30,000 of Boeing's ( BA ) U.S. West Coast factory workers will

make it harder for the planemaker to meet a 737 MAX production

target and stabilize the its supply chain, CFO Brian West said

on Friday.

West also told the Morgan Stanley Laguna Conference he

expects third quarter margins from the company's defense and

space unit to be negative, similar to those in the second

quarter.