GSTF Journal on Aviation Technology (JAT)

, 2:2

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

Energy-Saving Periodic Flight at Transonic Speeds

  • G. AmouyalAffiliated withDepartment of Aerospace Engineering, Technion, Israel Institute of TechnologyFlorida Inst. of Technology
  • , D. WeihsAffiliated withIsrael Institute of Technology


We examine possible energy saving by periodic changes in speed and altitude relative to steady state cruise, in the transonic regime. We develop a theoretical model of two-phase periodic flight with altitude variation in the transonic regime and compare it with a steady horizontal flight at the same average speed. The model predictions are verified by wind tunnel experiments. For example, by periodically accelerating from M=0.7 to M=1.1 while losing altitude, and then climbing back to the original height while decelerating, one can achieve savings of about 20% relative to steady flight at the same average speed and constant altitude.


Flight Mechanics Transonic Periodic Motion