Principal Engineer Quality: Bachelor of Science Degree in a STEM (Science, Technology, Engineering, and Mathematics) field with a minimum of 8 years of engineering experience in Quality Assurance, Manufacturing, Process, or Mechanical Engineering; Masters Degree in a STEM (Science, Technology, Engineering, and Mathematics) with a minimum of 6 years of engineering experience in Quality Assurance, Manufacturing, Process, or Mechanical Engineering. The above salary range represents a general guideline; however, Northrop Grumman considers a number of factors when determining base salary offers such as the scope and responsibilities of the position and the candidate''s experience, education, skills and current market conditions.