Hybrid Rocket Motor Guide

1. Introduction

Scope, goals, and how to use this guide

This reference consolidates design, manufacturing, testing, safety, and learning practices for a paraffin/N2O hybrid rocket motor in a university‑preparatory context.

2. Safety & Regulatory Compliance

U.S. federal rules, NFPA guidance, institutional oversight

• Institutional permission and supervision required.
• Reference NFPA 1122 (Model Rocketry) and applicable institutional policies.
• Maintain written test plans, checklists, and range safety procedures.

3. Design & Engineering

Propellants, chamber pressure, materials, injector, nozzle

Operating Pressure

Recommended starting range: 300–500 psi for educational static tests.

Materials

Evaluate 6061‑T6 Aluminum, 4130 Steel, and 304 Stainless Steel with conservative safety factors.

Injector

Simple showerhead injector with angled holes for swirl and mixing.

3.5 Ignition Systems

Options, tradeoffs, sequencing

• Pyrotechnic igniter (recommended for first prototype).
• Hot‑wire / e‑match with staged oxidizer flow.

4. Manufacturing & Assembly

Machining, casting, assembly, leak checks

Leverage machine shop and 3D printing for molds and fixtures. Document every step.

5. Testing & Instrumentation

Test stand, DAQ, procedures

Vertical tripod stand with load cell; log thrust and chamber pressure at ≥1 kHz.

6. AI‑Assisted Learning

Tutoring, design checks, analysis scripts

Use AI to explain concepts, verify calculations, generate analysis code, and draft documentation—always verify outputs.

7. Project Management & Documentation

Timeline, reviews, reports

Follow a 12‑week plan with PDR, CDR, hot‑fire, and final report milestones.

9. References

• NASA Glenn – Rocket Thrust Equations
• ATF – Hobby Rocket Motors (2004R‑7P)
• Nakka – Mechanical Design, Igniters, STS‑5000