I started with a zoom interview with a panel of 5-6 current employees, then proceeded to have in person site interviews. Overall, the process was moderately difficult. Just be prepared and you'll do just fine.
Supervisor applicants have rated the interview process at Northrop Grumman with 3 out of 5 (where 5 is the highest level of difficulty) and assessed their interview experience as 100% positive. To compare, the company-average is 74.2% positive. This is according to Glassdoor user ratings.
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