Total Impulse
225.0Ns
Burn Time
1.85s
Avg Thrust
121.0N
Max Thrust
294.0N
Thrust Profile (N)
1.85s Burn WindowEngineered by Contrail Rockets, the H121-HP is a 38mm solid rocket motor designed for high-power rocketry (HPR). As an official H-class motor, it delivers a total impulse of 225.0 Ns over a 1.85 second burn window.
With an average thrust of 121.0 N and a peak of 294.0 N, it features a neutral thrust curve optimal for heavy rockets requiring high off-the-pad acceleration.
Technical Specifications
Tripoli Rocketry Association, Inc.Diameter 38 mm
Length 516 mm
Hardware 38 20 S HP (185CC)
Delays (s) P
Specific Impulse 208.5 s
Peak Thrust 265.51 N
Peak Time T+ 0.04s
T/W Ratio 20.15
Propellant Standard
Profile neutral
Type hybrid
Sparky No
Mass Budget
612g TotalCasing (Dry)
502.0g
82.0%
Propellant
110.0g
18.0%
Live Sizing
Flight Envelope
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Comparable H-Class Alternatives
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