As a company that has recorded $13 billion in after-tax profits over the past five years, Boeing recognizes it cannot stand pat on salary. It has offered 11% over three years, plus a series of sweeteners, and says the average worker would gain $34,000 over three years. The union is seeking a 13% increase. Health care, pensions and other items also separate the two sides.

Outsourcing remains a key issue. For years, Boeing has been increasing the amount of outsourcing in its aircraft. Today, about 70% of the work on Boeing aircraft is done by outside employees.

"Boeing never has made 100% of the airplanes it builds," says Boeing spokesman Marc Birtel. "Sourcing from suppliers domestically and internationally has always been part of the Boeing business model and any other aerospace manufacturer's model."

As outsourcing has increased, he notes, "a number of our legacy airplane programs e.g. the airplanes other than the 787 are now comparable to the make/buy percentages for the 787, predominantly resulting from the sale of several former Boeing-owned operations."

The IAM says it is determined to protect the jobs it still has.

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