1/2A3-4T 13mm Engines Educator Bulk Pack for Model Rockets (24) (EST1788)

The Estes 1/2A3-4T Engine Bulk Pack provides dependable power for lightweight mini model rockets and is well suited for classrooms, youth groups, clubs, and other group launch activities. The compact 13 mm engines combine a quick thrust profile with a four-second delay, making them a practical choice for compatible rockets designed for smaller fields and manageable flight altitudes.

Each bulk pack includes twenty-four 1/2A3-4T engines, thirty starters, twenty-four starter plugs, and seventy-five squares of recovery wadding. With supplies for up to twenty-four launches included in one package, the bulk format makes preparation easier for educational programs, organized events, and frequent flying sessions.

The 1/2A3-4T delivers a total impulse of 1.25 N-sec with a maximum thrust of 8.30 Newtons or 1.9 pounds. Its thrust duration is approximately 0.30 seconds, followed by a four-second delay before ejection. The engine is rated for rockets with a maximum lift weight of 1.0 ounce or 28 grams.

Each engine measures approximately 1.8 inches or 4.6 centimeters long and has a 13 mm diameter. The engine weighs approximately 0.23 ounces or 6.5 grams and contains approximately 0.07 ounces or 1.9 grams of propellant.

The 1/2A3-4T can be used with compatible mini-engine model rockets, including models such as the Star Hopper. Its compact size and consistent performance make the bulk pack especially useful for educational rocketry, group activities, club launches, and repeated flights. Always verify the rocket manufacturer's recommended engine configuration before use.

Purchasers and users of Estes model rocket engines are responsible for following all applicable local, state, and federal laws, regulations, and safety standards. Model rocket engines must be handled and used only as intended and in accordance with established model rocketry safety practices. Estes Industries, LLC disclaims liability for personal injury, property damage, or other loss resulting from misuse, improper handling, or unauthorized use of its model rocket engines.