B4-4 Engines

The Estes B4-4 Engine is an excellent educational tool for classrooms, science clubs, and STEM enrichment programs. This 18 mm, single-stage engine is ideal for student-built model rockets weighing less than 3.5 ounces, offering a reliable and predictable flight experience that supports hands-on learning in physics, engineering, and aerospace topics. Its moderate thrust and 4-second delay give students time to observe key phases of flight—from launch to apogee to recovery.

With a thrust profile designed for smooth, controlled boosts and dependable deployment, the B4-4 helps reinforce concepts such as force, acceleration, and Newton’s Laws. The 4-second delay ensures recovery systems deploy near peak altitude, making each launch a clear demonstration of trajectory and timing. It's a dependable choice for educators who want safe, repeatable results across multiple launches.

Each package includes three B4-4 engines, four starters, and four starter plugs, providing sufficient materials for small group projects and lab-based rocket builds. The extra starter in each pack adds flexibility and peace of mind when planning classroom launch days. Estes' reputation for safety and performance means educators can confidently integrate model rocketry into their curriculum.

Whether you're guiding a single classroom launch or leading a schoolwide rocket event, the B4-4 engine provides a balance of safety, performance, and educational value. It pairs well with a wide range of Estes kits and enables students to directly engage with core STEM concepts in an exciting, hands-on format.

Estes B4-4 Model Rocket Engines are compatible with a large number of Estes rocket kits, including but not limited to: 

• 1225 Alpha
• 1292 Wizard
• 1261 Baby Bertha
• 1946 Boosted Bertha
• 1948 Big Bertha
• 1949 Viking
• 2008 Generic 2X
• 2021 Cadet
• 2056 US Army Patriot
• 2092 Mongoose
• 2169 Dragonite
• 2178 Hi-Flier
• 2452 Athena
• 2483 Phantom Blue
• 7000 Bull Pup 12D
• 7220 Crossfire ISX
• 7245 Comanche-3
• 7259 Nike-X
• 7281 Corvetter
• 7284 Starship
• 7291 Space Corps Centurion

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