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Estes Model Rocket Engine, Model 1/2 A3-4T, Pack of 24

(in stock)


Each pack contains igniters, igniter plugs, and recovery wadding. Letter indicates engine's maximum total impulse (equal to the engine's thrust in Newtons times the length of engine burn in seconds): A=2.5 N-sec, B=5 N-sec, C=10 N-sec. First number indicates engine's average thrust in Newtons. Second number is the delay time in seconds between end of thrust and start of ejection charge.

For example, an A6-4 engine has the same thrust and delay time as a B6-4 engine but burns only half as long. The 1/2A3-4T engine has half the average thrust of an A engine and is smaller than standard size (denoted by the "T").

Note: Rocket engines contain flammable solid material; there is an additional hazardous shipping charge for each shipment.

Note: Residents of CA, ND, NJ, and RI may be subject to additional state age or permit requirements when purchasing this item.


Shipping Information or Purchase Restrictions
  • Exclamation icon Flammable Solid - This product is/contains a DOT regulated hazardous material. Your order will incur a hazardous materials fee. Orders shipping to HI and AK are subject to review and may incur additional shipping charges.
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