A3-4T Engines

The Estes A3-4T engine is a mini single-stage model rocket engine designed for lightweight rockets, making it an excellent choice for classroom launches, student projects, and hands-on STEM programs. With a total impulse of 2.50 N-sec and a peak thrust of 6.80 newtons (1.5 lbs), this 13 mm diameter engine reliably powers rockets weighing up to 2.0 ounces (57 g). Its 4-second delay allows for a steady coast phase before ejection—helping students observe controlled flight and proper recovery system deployment.

Engineered for rockets that benefit from moderate thrust with a longer delay, the A3-4T features a thrust duration of 0.60 seconds. This balance of boost and delay makes it ideal for flight demonstrations, classroom experiments, and group launches where flight predictability and recovery timing are important for learning outcomes.

Each pack includes four A3-4T engines, four starters, and four starter plugs—providing everything educators need for multiple launches in a classroom or group setting. The inclusion of starters and plugs ensures reliable ignition, making launch preparation easier and allowing more time for instruction and experimentation.

Backed by Estes’ reputation for quality and dependable performance, the A3-4T engine supports hands-on learning in STEM education. Its consistent thrust, balanced delay, and classroom-friendly packaging make it a trusted choice for educators leading model rocketry programs.

ATTENTION: Estes Industries, LLC requires all purchasers and users of Estes® Model Rocket Engines to adhere strictly to all applicable local, state, and federal laws, regulations, and safety standards. The user assumes all responsibility for the safe and lawful use of Estes® products. Estes Industries, LLC expressly disclaims any and all liability for personal injury, property damage, or other loss resulting from the misuse, improper handling, or unauthorized application of its model rocket engines.