Adjustments to a code for an animated mobile banner

We need help adjusting JavaScript code for HTML5 banner ads. The project consists to have a banner animated with a car crashing into a wall, but this animation must start only when moving the phone right. We have a script monitoring the alpha, beta, gamma, but we need to find a way to add a conditional statement that triggers the animation. The one we have currently works randomly and works only in portrait mode. I don't understand how the alpha angle is calculated. We also have a function written in jQuery to display 2 texts and a logo one after the other in loop, but we need to have a similar code using simple JavaScript instead of jQuery because the banner has to be very lightweight (40k max) and the jQuery file is too heavy. The animation images and the actual script will be provided. You can see what it looks like right now at this address: [login to view URL] (of course you have to see it on a mobile phone otherwise the animation won't start). Thank you!