Got in accident and didnt know it

I have to be REALLY careful with this, lots of tail swing.

 

I want to ask your advice on this same topic. I recently had the same problem as Dirtjersey in a tight parking lot when my blind-side trailer rear overhang struck an SUV, small scratch on trailer, considerable damage to SUV, and didn't even know it. I swung too hard left in an effort to line myself better with an arcing turn to the right to clear other obstacles. Is there some formula or rule-of-thumb one can use that calculates lateral distance needed before making the turn and trailer/tandem length and distance? The 48ft trailer I am using also have a welded entension of about 3 feet added on for a lift-gate. Thank you.

 

Candler NC, TA. O_O Nuff said.
The rule of thumb going forward is the same as backing up. Getting out to look. The tighter the angle, the more the forward motion of the tires becomes a rotating motion. If I'm in a situation like in many rail yards or in places where the opposing row of parked trucks is so close to my nose that I have to jack, I stop midway into the turn to get out and check the trailer swing. Usually a couple inches is enough to not worry about a collision.