Acceleration Environment Coordinate

Acceleration Environment Coordinate System Used in NASA-STD-3000

This system is based on the direction a body organ (e.g., the heart) would be displaced by acceleration. Table II in this figure (and in particular, system 4, which is based on displacement of body fluids) explains the most commonly employed terms.

Figure 5.3.1-1 (Part 1 of 2) Acceleration Environment Coordinate System Used in MSIS

Acceleration Environment Coordinate System in picture format

Reference: 101, NASA-STD-3000 436

Figure 5.3.1-1(Part 2 of 2) Acceleration Environment Coordinate System Used in MSIS

LINEAR MOTION

Direction of Acceleration

Inertial Resultant of Body Acceleration

Acting Force

Acceleration Description

Reaction Force

Verticular Description

Forward

+a_x

Forward accel.

+G_x

Eye Balls In

Backward

-a_x

Backward accel.

-G_x

Eye Balls Out

Upward

-a_z

Headward accel.

-G_z

Eye Balls Down

Downward

+a_z

Foorward accel.

+G_z

Eye Balls Up

To Right

+a_y

R. Lateral accel.

+G_y

Eye Balls Left

To Left

-a_y

L. Lateral accel.

-G_y

Eye Balls Right

ANGULAR MOTION

Roll Right

-R_x

Cartwheel

Roll Left

-p

+R_x

Pitch Up

-R_y

Somersault

Pitch Down

-q

+R_y

Yaw Right

+R_z

Pirouette

Yaw Left

-r

-R_z

Reference: 380; NASA-STD-3000 435

Footnotes:
Large letter, G, used as unit to express inertial resultant to whole body acceleration in multiples of the magnitude of the acceleration of gravity.
Acceleration of gravity, g, = 980,665 cm/sec² or 32.1739 ft/sec².