Exposed to the hot exhaust emitted by four General Electric F118-100 engines, the B-2's aft deck has faced cracking problems for several years. The USAF has sustained the type's structural integrity through a series of interim structural repairs.
© Staff Sgt Bennie Davis III/US Air Force
Northrop's engineers have now identified a permanent solution to the problem, which requires installing a redesigned structure, says aft deck upgrade programme manager Chuck Osberg.
Details of the redesigned structure have not been disclosed, but the fix involves geometrically reconfiguring the basic materials in the aft deck, Osberg says. The redesigned shape is similar to the previous structure, but the reconfigured materials allow the "deck to breathe, if you will", he says.
The outer mould line of the B-2 will be unchanged with the reconfigured aft deck, he adds. The shape of the B-2's outer skin is a major factor in measuring the aircraft's radar cross-section.
The USAF has decided to launch an accelerated production programme that effectively skips a development and demonstration phase, Osberg says. Northrop expects to have a contract completed in the near term to begin the installations.