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The Malewicki equations (or Fehskens–Malewicki equations) for sub-sonic endo-atmospheric rocket flight describe the maximum altitude and coast time of a vehicle such as a model rocket. Aerospace engineer and inventor Douglas Malewicki first published them as a technical report by the model rocket company Estes Industries in 1967.
References
Model Rocket Altitude Prediction Charts Including Aerodynamic Drag, Douglas J. Malewicki, Technical Report No. TR-10, Estes Industries, Inc., Penrose, Colorado, USA, 1967