"Boomerang Flight Dynamics"

11 March 2022
12:00 pm to 1:00 pm
"Boomerang Flight Dynamics"
John Vassberg, PhD
Chief Design Officer

ABSTRACT:  Aerodynamic characteristics and flight dynamics of boomerangs are investigated. A basic aerodynamic model, developed in the 1960’s, is expanded upon using Blade Element Theory. The new aerodynamic model is coupled with a gyroscope model for rudimentary analyses. Some significant findings are made regarding the radius of a boomerang’s circular flight path, the required inclination angle of its axis-of-rotation, its trim state, as well as its dynamic stability. These discoveries provide a basic understanding of how the interplay between aero- dynamic forces and moments, and gyroscopic precession combine to return the boomerang to its rightful owner by way of a circular flight path.
      A traditional V-shaped boomerang design is developed as a case study for further detailed analyses. Unsteady Reynolds-averaged Navier-Stokes solutions provide accurate aerodynamic characteristics of the subject boomerang. The high-fidelity aerodynamic model is coupled with the equations of motion to provide accurate six-degree-of-freedom simulations of boomerang flight dynamics. Boomerang orientation during its flight trajectory is described by the classical Euler angles.

BIO:  Dr. Vassberg is currently the Chief Design Officer of JetZero, a new start-up company focused on dramatically reducing aircraft emissions for the commercial transport industry.
      After almost 40 years with Boeing, Dr. Vassberg recently retired as the Chief Aerodynamicist and Technical Lead of BCA Advanced Concepts Design Center in Southern California. He was a Boeing Technical Fellow, is an AIAA Fellow, and recipient of the AIAA Aerodynamics Award in 2012 and the International Cooperation Award in 2017. Prior to this, he was the Chief Aerodynamicist of Boeing’s Phantom Works and Research & Technology organizations, and as such, he was the Principal Investigator of the Advanced Joint Air Combat System, Speed-Agile Configuration Development (SACD) and Over-Wing Nacelle programs. The SACD Program received the 2013 Aviation Week Laureate Award in Aero and Propulsion.
      Dr. Vassberg received his PhD from the University of Southern California in 1992, and his MS and BS from Texas A&M University in 1981 and 1980, respectively, all in Aerospace Engineering.