Its so ground crew not wearing helmets wouldn't bonk there heads on the wings and leading edge.
Ground crew waking up with headaches?  Introducing Bonk-Away stripes.  The latest technology in human head protection.
Helemts are costly and eyes are inefficient.  With Bonk-Away stripes you'll never have to buy a helmet or use your eyes again.
And they're easy to apply.  Just use a piantbrush. 
You can use then anywhere!  Use them on the plane, in the cockpit or even in the hanger.
Try Bonk-Away today!
And this groundbreaking technology is available at the incredibly low price of only $19.95 
But if you order today we'll double your order.  Yes, that's two Bonk-Away stripes for the low low price of only $19.95.  
But that's not all.  If you order in the next ten minutes we'll include a bayer asprin, a dixie cup and a 4 oz. flask of natural Lake Erie water as our free gifts to you, even if you return the Bonk-Away stripes.  
Yes, that's two Bonk-Away stripes, a bayer asprin, a dixie cup and a 4 oz. flask of natural Lake Erie water for the incredibly low price of only $19.95.  
We'll even include the paintbrush!
Order now.  Operaters are standing by.