Unified Flight Mechanics and Aeroelasticity for Accelerating, Maneuvering, Flexible Aircraft
Abstract
This paper reveals new insights in the aeroelasticity and flight mechanics of flexible aircraft by obtaining and solving the equations of motion for a flexible, accelerating, rotating aircraft. We illustrate the approach for three cases of increasing complexity: The first case is a "sprung" pendulum. It shows when rigid body angular velocities can be important in the flexibility equations as they approach as the flexible frequencies. The second ease is a typical section airfoil on an accelerating, rotating fuselage. It applies Lagrange's equations to a longitudinal problem in inertial coordinates, then transforms the equations to noninertial, body - fixed coordinates for solution. It also shows when rigid body rotations and longitudinal accelerations must be included in the flexibility equations. The third case is the general longitudinal/ lateral motion of all accelerating, rotating, flexible vehicle. Rather than setting up the general problem in inertial coordinates and then transforming to body fixed coordinates, instead we use the idea of "quasi coordinates". We establish a general form for Lagrange's equations in the noninertial, body fixed coordinates. The paper gives the general equations and reduces them to a special case of a "flat airplane. It also gives guidelines as to when the rigid body rotations and accelerations are important factors in the flexibility equations.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 2000
- Accession Number
- ADP010479
Entities
People
- James J. Olsen