STRUCTURAL ANALYSIS

Rail Guide Loads

Launch rail attachment strength and lateral load analysis.

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01

Launch Forces

Force on rail guides during launch comes from:

  • Thrust misalignment
  • Crosswind
  • Asymmetric drag
Lateral Force
Fguide=m×alateralF_{guide} = m \times a_{lateral}
Typical lateral loads: 5-20% of thrust for well-aligned rockets.
02

Guide Placement

Minimum Separation
Lsep>2×DL_{sep} > 2 \times D

Optimal placement:

  • One guide near aft end
  • One guide at or forward of CG
03

Attachment Strength

Guide TypeStrengthWeightDrag
Launch lug (tube)LowLowHigh
Button (Delrin)ModerateLowLow
Button (Aluminum)HighModerateLow
Conformal rail guideHighestModerateLowest
For high-power rockets, use rail buttons or conformal guides. Launch lugs create significant drag at high velocities.

SOURCES

References

Community Resources

  • Launch rail guides

    Rocketry Forum discussion on guide types and installation

  • Rail Guides — Rocket Lab Delta

    Comparison of rail guide types with recommendations

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