# Accelerations and rates at a far away point.

1. Aug 17, 2010

### jean507

Considering I know the accelerations [ax, ay, az] and angular rates [p, q, r] at the center of gravity (cg) of an airplane. How can I calculate the accelerations and angular rates at the pilot's position (p).

I have information about the distance between the cg and the pilot's position which could be characterized by a 3 dimensional vector (R).

Any help would be appreciated.

Best regards to all.

Last edited: Aug 17, 2010
2. Aug 18, 2010

### AJ Bentley

You can't.
There isn't enough information.

Consider a simple situation where the COG measures a vertical acceleration. With no forward acceleration but a non-zero rotation in pitch.
This motion could indicate that the craft is climbing rapidly in a pure vertical accelerated ascent and rotating, or it could mean that it is spinning around an axis (looping).

You need the velocities. (Or you need to be able to derive them - which means integrating the acceleration over time)

3. Aug 18, 2010

### jean507

I understand what you mean with your example, this is exactly what I could not understand (how to differentiate between a rate and an acceleration as they could have the same effect on a far away point).

I have a continuous signal over time. I am working with a flight simulation environment. As matter of fact, I am already integrating the accelerations twice to get the speeds and displacements.

Is it possible to do then? How?