What is the fastest Boeing military jet? The question is somewhat broad and depends on what one includes. As yet, Boeing has not developed and brought into service a single original manned fighter jet. Most of its jet-powered military aircraft were inherited from its acquisitions and mergers over the years (particularly Rockwell and McDonnell Douglas). It has completely rebuilt and redesigned the old F-15 and F/A-18 aircraft, effectively producing new aircraft, but they are still based on pre-Boeing platforms.