Propellant Mass Fraction

Calculate the propellant mass fraction (PMF), a key performance metric for rockets and spacecraft, based on initial (wet) and final (dry) mass.

Initial Mass (Wet)

Final Mass (Dry)

Unit

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The chart will show mass distribution and fractions

Propellant Mass Fraction Theory & Notes

The Propellant Mass Fraction (PMF) is a measure of the vehicle's performance, indicating how much of the total mass is propellant.
It is defined as the ratio of the propellant mass (m_p) to the initial (total) mass (m_0) of the vehicle.
Formula: PMF = m_p / m_0 = m_p / (m_s + m_p), where m_s is the structural mass (dry mass).
A higher PMF generally means a more efficient design, as more mass is dedicated to fuel than structure.
This value is crucial for calculating the performance capabilities using the Tsiolkovsky rocket equation.

Open Source & Transparent

This tool is open source and the underlying logic is fully transparent. You can view the source code, understand the calculations, and even contribute improvements to make it better for everyone.

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