Total Impulse
2441.0Ns
Burn Time
6.40s
Avg Thrust
379.0N
Max Thrust
1036.0N
Thrust Profile (N)
6.40s Burn WindowEngineered by Contrail Rockets, the K404-SP is a 75mm solid rocket motor designed for high-power rocketry (HPR). As an official K-class motor, it delivers a total impulse of 2441.0 Ns over a 6.40 second burn window.
With an average thrust of 379.0 N and a peak of 1036.0 N, it features a regressive thrust curve optimal for heavy rockets requiring high off-the-pad acceleration.
Technical Specifications
Tripoli Rocketry Association, Inc.Diameter 75 mm
Length 1016 mm
Hardware 75 40 S SP (2050CC)
Delays (s) P
Specific Impulse 354 s
Peak Thrust 670.65 N
Peak Time T+ 0.011s
T/W Ratio 9.31
Propellant Standard
Profile regressive
Type hybrid
Sparky No
Mass Budget
4150g TotalCasing (Dry)
3447.0g
83.1%
Propellant
703.0g
16.9%
Live Sizing
Flight Envelope
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Comparable K-Class Alternatives
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