[A/S] Airstream Brake question

[SHMossLanding@xxxxxxx]

I have had the 1965 Overlander sitting by the side of my house to work on it 
for about 3 weeks.  When I went to move it today, the right rear tire was 
locked up.  I backed up for a short distance and it seemed to release it.  
WhenI parked it, from under the trailer near the door, within the bottom skin 
was a sound like a flasher would make about every 30 to 45 seconds.  Can 
anyone help me with what this noise might be and why the brakes would have 
locked up?  Has anyone else experienced this?

NEED HELP!!!

                                                                   Thanks,
                                                                          
Chuck & Lynn   
                                                                         1965 
Overlander