Calculateur de Rapport Poussée/Poids
Calculez le rapport poussée/poids d'un véhicule spatial.
Thrust-to-Weight Ratio
1.4128
Thrust-to-Weight Ratio vs Thrust
Formule
## Thrust-to-Weight Ratio The TWR determines whether a vehicle can lift off and how quickly it accelerates. ### Formula **TWR = F / (m * g)** - *F* = engine thrust in newtons - *m* = total vehicle mass - *g* = local gravitational acceleration TWR must exceed 1.0 for liftoff. Most launch vehicles aim for 1.2 to 1.8 at ignition.
Exemple Résolu
Saturn V first stage: 7 607 000 N thrust, 549 054 kg.
- 01TWR = F / (m * g)
- 02Weight = 549054 * 9.80665 = 5 384 000 N
- 03TWR = 7607000 / 5384000
- 04TWR = 1.413
Questions Fréquentes
Can a TWR below 1 be useful?
Yes, for in-space manoeuvres. Ion engines have tiny TWR (0.001 or less) but accumulate large delta-v over time.
Why not maximise TWR?
Very high TWR means excessive acceleration, which wastes fuel fighting drag in the lower atmosphere and stresses the structure.
Does TWR change during flight?
Yes. As fuel burns the mass decreases while thrust stays roughly constant, so TWR increases throughout the burn.