Spoilers and Horizontal stab authority - any issues?
 

Whilst bored and sitting at the back of a 757 recently, I started thinking about the rumble and gentle shimmy from the spoilers that is discernable when they kick up. Does the turbulent air cause a/c designers any problems, or restrictive operating conditions?

Although they're mounted outboard (clear of the elevators)are there any issues with airflow when the aircraft banks or side-slips?

Just curious.

Simple answer. Yes.

Obviously you do your best to design it out, and as you noted spoilers are generally outboard (though there can be overlap with the tail). But some configurations - military types - say - don't have the luxury of such high aspect ratios as airliners, and are physically smaller too, so interference is possible.