We were taking off out of SEA with a low ceiling and one generator inop with APU as the second generator. In the clouds shortly after takeoff the FO turned off the APU so were one one generator for a while. It worked out ok since we restarted it but could have been a problem.
What made the DCA takeoff with the over voltage more interesting was our clearance was runway heading for vectors. When we took off with a company Lear talking to tower behind us for takeoff clearance realized we were headed straight into the prohibited area because they changed runways. I turned left to avoid the prohibited space and finally informed tower I need a heading so they reversed to a right turn which took over 30 degrees bank to avoid entering prohibited area and that is when the panel lights went full bright with a pegged out volt meter. It all worked out fine but I didn't have to land in the Hudson so feel fortunate.
Julie Andrews was on the Lear behind us and I was flying the other half of the cast of her movie SOB where she briefly showed her breasts. The cast was met by press at every airport we landed at on that five day trip asking why she did it. She said it was in the script. I know, off topic.