Roller Coast Physics - G Force sensing Application for iPhone and iPod Touch


New member
For all of those with iPhones and iPod Touches you can download an app called "Roller Coast Physics" that is really quit interesting. It is designed for roller coasters to see what sort of G-Forces you are pulling, but we used it on our trip to Europe to see what the plane was pulling during take off, landing and turbulence.

What we found was that during our rather smooth flights the most G-Forces pulled (so the most movement you would feel) was during taxi and the plane bouncing over the uneven concrete. During flight you would barely ever see (even during turbulence) more then 5-10% +/- 1G. Take off would provide very little deviation from 1G and landing would sometimes pop up to 2G for a millisecond or two as the wheels touch down.

Since modern aircraft are designed to handle many Gs over and under gravity you can see how little effect turbulence has on the actual aircraft.


Staff member
I have to agree. On some of the runways/flights I've been on, the ride during taxi is probably what I'd consider light to moderate. Some of those old DC9 aircraft have poor shocks on them, and the plane bounces annoyingly.

Did you have your meter out during any turbulence?


New member
Yeah, we had it out during some of what little turbulence we experienced. During cruise I would classify what we experienced as light and it barely registered at all on the accelerometer of the iPod Touch using the Roller Coaster Physics app. Some of the lower level turbulence we experienced during landing was a little more intense but I would still classify it as light and it maybe registered as 5-10% +/- 1G on the iPod.

Moving the iPod to place it on the tray table produced more noticeable accelerations then the actual aircraft was producing!