# Mass-Spring system on an accelerating jet

Imagine a perfect mass spring system. If it's put on an accelerating plane, how will the motion change? Is the plane's acceleration like a driving/damping force, where:

$$F_{\text{driving}} = \text{mass} \times \text{plane's acceleration}$$

• Flip the question around (so to speak) what if, instead of running the problem horizontally you hung the mass from the spring? – dmckee Mar 28 '15 at 20:42

The acceleration of the plane will cause an offset in the motion of the mass/spring system; if it was centered on x=0 when the plane was stationary, its motion will now be centered around $x = -\frac{m\cdot a}{k}$ where $k$ is the spring constant, and $F = m\cdot a$ is the force needed for the mass to accelerate with the plane. If the plane is accelerating in the +x direction, the displacement will be in the -x direction.