Has that agreement been voted on and recognized by the NMB? No. Therefore, is it a binding document?
From the "Joint Council" document, "At an appropriate time mutually agreed to by the International Presidents of TWU and lAM after the closing of the merger transaction between American Airlines and US Airways, tile Association shall file an application with the National Mediation Board for Investigation of a single carrier representation dispute among the Carrier's Employees, and for certification of the Association as the representative of the Employees and extinguishment of the Labor Partners' pre-merger certifications at American Airlines and US Airways."
From the Q&A of the "Asociation" announcement:
"Q: When will the Association begin bargaining a combined/joint contract?"
"A. After the airlines' merger is completed and the membership approves a TWU/IAM joint representation alliance."
AND
"Q: Willi have the opportunity to vote on whether or not I am represented by the Association?"
"A: Yes. Following the completion of the American- US Airways' merger, the Associations will file representation applications with the National Mediation Board (NMB), a federal agency, which will culminate in three separate elections, one for each of the Mechanic & Related, Fleet Service and Stores classifications. You will vote in the election of the classification in which you work with others from both carriers."