Skip to the mission
Exit
Mission 3 · Model Rocketry

Design a Stable Model Rocket

CGCPStatic margin 0.83 cal

2D drawing · + and − zoom, 0 resets

Illustrative model rocket. Cyan ring: centre of gravity (CG). Amber ring: centre of pressure (CP).

Educational simulation · simplified physics, illustrative values · not flight data

Learn · step 1 of 3

Parts and forces

Goal: Open the exploded view, find each part, and decide which force the fins provide.

Four forces act on a rocket in flight: thrust from the motor pushes it up, weight pulls it down, drag from the air slows it, and when it tilts, the air pushes sideways on the fins. That sideways push swings the tail back in line, like the feathers on a dart.

When the rocket tilts, which force do the fins mainly provide?

About this mission

Shape the nose and fins, add ballast and choose a motor until the centre of gravity leads the centre of pressure by one to two calibres.

You will

  • Find the centre of gravity
  • Find the centre of pressure
  • Make the design stable, and robust to a heavier motor

Concepts in this mission

  • Centre of gravity
  • Barrowman centre of pressure
  • Static margin
  • Thrust-to-weight

Part of the Model Rocketry track, with its course description and a lesson plan for each age level.

About the model

An educational simulation, not a validated engineering tool. The physics is real but simplified and the numbers are illustrative values chosen for learning; each step says what it leaves out. Do not use it to design real flight hardware.

Independence, safety and privacy

  • Interactive missions use simplified models and simulated, illustrative values. They are labelled as such and are not flight data.
  • Missions never ask for a name, school, age or contact details. Progress is stored only in this browser and can be cleared at any time. This site uses Google Analytics to count page visits and mission steps. Some of the site's existing tutorials ask visitors to sign in with a Google account. If you are under 18, check with a parent or guardian before signing in.
  • Space Academy is part of an independent ISHAVASYAM.ORG education initiative. It is not affiliated with, endorsed by, or run on behalf of ISRO, IN-SPACe, NSIL or the Department of Space.
  • Learning here does not register anyone for, or make anyone eligible for, any national or international competition. Each competition's organisers set its rules and eligibility.
  • Written for learners aged 14 to 18. Anyone may play the self-paced missions; enquiries from under-18s need a parent or guardian.
  • This Academy never teaches how to make rocket motors, propellants or energetic materials.
  • Any launch or drop test happens only under the supervision of qualified adults and within applicable local rules.
  • Simulations here are for learning. They are simplified and must not be used to design real flight hardware.

Space Academy · Space portal

Settings

View
Graphics quality
Motion
Narration

Touch and keyboard

Drag, or arrow keys
Rotate the model (select the model first with Tab)
Pinch, scroll, or + and −
Zoom
0, or the target button
Reset the view
Tab and Enter
Move between and use every control, including parts in the list
Escape
Close this window

Progress

Your progress is kept only in this browser. Nothing you do here is sent to us apart from anonymous counts of steps completed.