Prime Contractors

Six companies dominate the defense aerospace internship landscape: Boeing, Lockheed Martin, Northrop Grumman, RTX (Raytheon), L3Harris, and General Dynamics. Together they hire thousands of interns every year and run some of the most structured internship-to-career pipelines in the industry.

What makes prime contractor internships different from startups or government programs:

• Scale. Northrop Grumman alone hires ~2,000 interns per year. Boeing places thousands across 15+ locations.
• Structure. Formal programs with defined start/end dates, mentorship, and performance evaluations. Return offers for top performers.
• Security clearances. Most positions require or lead to a Secret or Top Secret clearance — a career accelerator in the defense sector.
• Early deadlines. Boeing Engineering closes in October. Lockheed Martin HS closes in December. If you're looking in March, your best options are the rolling programs at Northrop Grumman, L3Harris, and RTX.

Boeing

The largest aerospace company in the world. Interns work across engineering, finance, IT, supply chain, and manufacturing at 15+ U.S. locations. The engineering track is the flagship — but it closes in October, six months before most students start looking. The finance internship (still open until March 11) is a way in the door. The Core Plus Aerospace program places high schoolers in manufacturing roles at Boeing factories in Washington and South Carolina.

Lockheed Martin

The world's largest defense contractor. Interns are placed across four business areas: Aeronautics (F-35, F-16), Missiles and Fire Control, Rotary and Mission Systems, and Space (Orion, GPS satellites). The high school Space internship places students aged 16+ at Lockheed facilities for paid work — one of the few HS programs at a major prime. College positions are posted rolling starting in fall. Most require security clearance, which means US citizenship.

Northrop Grumman

Roughly 2,000 interns per year on a rolling basis — one of the largest and most accessible prime contractor programs. Interns work on the B-21 Raider, space systems, cybersecurity, and advanced weapons. The wide pay range ($15–46/hr) reflects the variety of roles from technician to graduate engineering. The rolling deadline makes Northrop one of the best options if you've missed other deadlines.

RTX / Raytheon

Three business units: Raytheon (missiles, defense electronics), Pratt & Whitney (jet engines), and Collins Aerospace (avionics). College internships run 10–12 weeks and are posted September through March. RTX also runs a rare paid HS internship for graduating seniors focused on manufacturing and aerospace. Three units means three different cultures — Pratt & Whitney in East Hartford feels different from Raytheon in Tucson.

L3Harris

Named a Top 100 Internship Program. Specializes in communication systems, electronic warfare, space and intelligence systems, and sensors. Rolling admissions with no single deadline. The pay floor ($14/hr) is lower than other primes, but engineering and software roles pay $25–38/hr. Some positions accept non-citizens with work authorization — more flexible than most primes. Melbourne, FL is the headquarters and has the most intern positions.

General Dynamics — Electric Boat SHIP

One of the only paid high school internships at a major defense contractor. The SHIP (Summer High School Intern Program) places HS juniors at Electric Boat's submarine shipyard for eight weeks of paid work on Virginia-class and Columbia-class nuclear submarine construction. Limited to Groton, CT and North Kingstown, RI. Must be a US citizen who has completed junior year by June.