Estes Rocket Motors - B4-2 (Pack3)

This bulk pack of 72 Estes Rocket Motors B4-2 (Pack3), part number D-ES1601, provides dependable 18 mm single-stage power for model rocket flights. The B4-2 is designed for rockets weighing less than 4 oz (113 g), including the engine, and features a 2-second delay for smooth deployment.

Each Pack3 includes engines, starters and plugs so you can prepare multiple flights efficiently. The B4-2 offers a balanced thrust curve and total impulse suited to lightweight models within the stated lift weight.

Key Specifications

• Length: 2.8 in. (7 cm)
• Diameter: 18 mm
• Estimated Weight: 0.66 oz (18.7 g)
• Total Impulse: 5.00 N-sec
• Time Delay: 2 seconds
• Estimated Max Lift Weight: 4.0 oz (113 g)
• Max Thrust: 13.20 N (3.0 lbs)
• Thrust Duration: 1.10 seconds
• Initial Weight: 0.66 oz (18.6 g)
• Propellant Weight: 0.27 oz (7.6 g)
• Quantity Per Pack: 3

What’s Included Per Pack

• 3 x B4-2 rocket engines
• 4 x starters
• 4 x plugs