Four Forces

An interactive 3D visualisation of lift, weight, thrust, and drag — explore how an aircraft climbs, descends, and holds level flight.

Static diagrams show what the four forces are and which direction they act. What they cannot show is how the forces change relative to each other as the pilot changes speed or attitude. A student who has only seen diagrams may be able to name the forces but won’t yet have the intuition for why reducing power causes a descent, or why raising the nose alone is not enough to climb.

This tool makes the force balance dynamic. Because the arrows resize in real time as you move the sliders, the relationship between pilot input and force output becomes something you can feel your way through rather than just recall. That is the gap it closes: between “I’ve memorised the four forces” and “I understand how they interact.”

banking

Aircraft: Bristol F.2B (First World War) — public domain, Canadian Ingenium museum

Description

The Four Forces tool shows a 3D aircraft with four labelled force arrows — lift, weight, thrust, and drag — that grow and shrink in real time as you adjust the controls. Two gauges show airspeed and rate of climb or descent.

There are two sliders:

• Power — increases or decreases engine thrust
• Attitude — pitches the aircraft nose up or down

As you move the sliders, the arrows and gauges update to show the new balance of forces and where the aircraft is headed. A physics model drives the response; the airflow particle stream and weight-component decomposition during climbs make the underlying mechanics visible. Multiple embeds on a page (or across tabs) synchronise via BroadcastChannel, useful for presenter/slide pairing.

For instructors

Use it during ground briefings to show concepts that are otherwise hard to describe:

• Straight and level flight — demonstrate that lift equals weight and thrust equals drag, and how changing one force disturbs the balance
• Climbing and descending — show how excess thrust produces a climb, and how reducing power causes a descent even with the same attitude
• The stall — if your aircraft’s stall speed is configured, the tool shows lift collapsing and the nose dropping when speed falls too low
• Turns — enable the bank control to show how lift must increase to maintain altitude in a turn, and how total drag rises as a result

The tool works in any modern browser — a laptop or tablet connected to a projector is all you need.

For trainees

Try it yourself between lessons to build intuition:

1. Set full power and watch the aircraft accelerate and climb
2. Reduce power gradually — notice how the rate of climb decreases, and what throttle setting holds level flight
3. Raise the nose at low speed and observe how the drag arrow grows relative to thrust
4. Lower the nose and add power — watch how quickly speed and lift recover

Experimenting here costs nothing and reinforces what you cover in the air.

Embedding this component

<script type="module">
  import 'https://unpkg.com/@open-aviation-solutions/components/dist/lib/define.es.js';
</script>

<four-forces height="400px" model-path="/path/to/aircraft.glb"></four-forces>

Attributes

Attribute	Default	Description
height	400px	CSS height of the component
model-path	/aircraft.glb	URL to the GLTF aircraft model file
v_ne	—	Never-exceed speed (kts). Sets ASI scale maximum and draws red radial line
v_no	—	Normal operating speed (kts). Top of green arc, bottom of yellow arc
v_1	—	Stall speed clean (kts). Bottom of green arc
cruise-kts	100	Airspeed at nominal cruise. Calibrates the ASI needle to the aircraft’s actual speed range
banking	—	Boolean. When present, shows a bank angle slider. Banking tilts the lift vector and displays its vertical and horizontal components
show-help	—	Set to "false" to hide the in-component help (?) link

Dependencies

Requires three (≥ 0.184) as a peer dependency:

npm install three @open-aviation-solutions/components