Total Impulse
355.0Ns
Burn Time
1.74s
Avg Thrust
203.0N
Max Thrust
433.0N
Thrust Profile (N)
1.74s Burn WindowEngineered by Contrail Rockets, the I221-PVC is a 38mm solid rocket motor designed for high-power rocketry (HPR). As an official I-class motor, it delivers a total impulse of 355.0 Ns over a 1.74 second burn window.
With an average thrust of 203.0 N and a peak of 433.0 N, it features a regressive thrust curve optimal for heavy rockets requiring high off-the-pad acceleration.
Technical Specifications
Tripoli Rocketry Association, Inc.Diameter 38 mm
Length 719 mm
Hardware 38 28 M PVC (370CC)
Delays (s) P
Specific Impulse 289.5 s
Peak Thrust 482.75 N
Peak Time —
T/W Ratio 29.15
Propellant Standard
Profile regressive
Type hybrid
Sparky No
Mass Budget
710g TotalCasing (Dry)
585.0g
82.4%
Propellant
125.0g
17.6%
Live Sizing
Flight Envelope
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