Boeing is conducting tests to prepare the Delta III rocket for its flight next year, after two initial launch failures.
Boeing and the Delta second-stage engine supplier Pratt & Whitney say they are "very encouraged" by initial results from the improved RL10B-2 second stage engine combustion chamber brazing process.
Voids in the brazing process caused weakened joints in the combustion chamber, contributing to the failure of the second Delta III launch last May.
P&W has produced six RL10 combustion chambers using the new process and more will follow before it declares the production method a success.
Source: Flight International