Rocketry & Propulsion Tools

Find the centre of pressure with the Barrowman method, compare it with your centre of gravity and read the static margin in calibers — then calculate the nose ballast needed to reach a stable margin.

Estimate ballistic coefficient, stagnation-point heat flux, peak heating, peak deceleration and total heat load along a constant-angle entry — the numbers that set a heat shield's size and shape.

Simulate a model rocket's powered ascent and coast to predict apogee, time to apogee and the best motor delay — then see exactly where a chosen delay fires the ejection charge.

Fly a two-dimensional point-mass ascent: set mass, thrust, burn time, drag and a pitch-over programme, then read apogee, downrange, max-Q, max Mach and max g from a live trajectory plot.

Check the three numbers that decide whether a rocket leaves the rail safely: liftoff thrust-to-weight, rail-exit speed and the wind limit — with drag included and a pass/fail checklist.

Stack up to five stages, enter propellant, dry mass and Isp for each, and get stage-by-stage delta-v, liftoff mass, payload fraction and the margin against your mission target.

From chamber pressure, temperature, gamma, molar mass and throat size, solve the isentropic nozzle: mass flow, exit Mach, thrust, Isp, c* and the optimum expansion ratio for sea level or vacuum.

Size a recovery parachute for a target descent rate, then see the impact speed, landing energy and wind drift from deployment altitude — with spill holes and clusters included.

Compare LOX/LH2, LOX/methane, kerosene, hypergolics, solids and hybrids on specific impulse and bulk density — then size the tanks and see the delta-v the same propellant mass buys.

Paste a thrust–time curve and get total impulse, burn time, average and peak thrust, the NAR/TRA impulse class and a thrust-to-weight check against your rocket's all-up mass.