This record contains the global flight data variables measured at the aircraft center of mass location. The variables are divided into the following categories:

Mass and Forces

This category contains the total mass (mTot) and inertia tensor (Ixx, Iyy, Izz, Ixy, Ixz, Iyz) such that the contribution from the variable mass properties of the fuel tank (for aircraft with combustion engines) is also included. The loadFactor is the total lift force divided by the gravitational force, and thus it is analogous to the G-force along the body z axis. 

Position and Orientation

This category contains the aircraft position in the world frame (positionAC), its orientation in Euler angles (phi, theta, psi), angle of attack (alpha), sideslip angle (beta), track angle (track) and flight path angle (gamma). Additionally, it contains a dedicated variable for altitude (alt), which actually equals -positionAC[3].

Velocities

The aircraft velocity is resolved in two frames of reference, namely in the world frame (vWorld) and the aircraft body frame (vBody), which are also shown in Figure 1. The total velocity (vTot) is the magnitude of the aircraft velocity vector. Additionally, this category contains the aircraft Mach number (mach) and ground speed (vGround), which is the velocity of the aircraft projected on the world x-y plane.

Figure 1: World frame and body frame.

Atmospheric Properties

This category contains the pressure (pAlt), static temperature (Talt), air density (rhoAlt), speed of sound (aAlt) and dynamic viscosity (muAlt) at the flight altitude as well as the dynamic pressure (qAC).