The USS Suquehanna and the USS Powhatan were the same class of ship. They were both launched in 1850, the Susquehanna in Philadelphia and the Powhatan in Norfolk. As far as the armement of the Susquehanna, during the Civil War it had 12 IX Dahlgrens broadside, (2) 150 Pounder (8 inch) Parrott Rifles in swivel mounts and a 12 pounder Howitzer. After the war it was upgraded with XI Dahlgrens. I have been reading conflicting accounts about the gun placement and compliment. One report talked about 2 swivel guns mounted fore and 2 swivel guns aft but not what they were. This was during the battle with the CSS Virginia. The Susquehanna also had a short run-around with her, too. During this campaign, the Susquehanna received the 2 Parrotts and the report said that they were placed broadside and were used to bombard the forts at Sewells Point. I think it would be realistic, though, to place the Dahlgrens (3 guns forward of the Wheels, Port and Starboard and the same set up aft of the wheels. As to the positioning of the Parrots, I´m not sure but maybe the same set up as the Kearsarge.
I have recently been trying to find out as much info as I can about the Susquehanna. I want to build it out of wood at about 1/96 scale. I have ordered Peter Barrett´s book about it but it is not yet arrived. I have also found plans for the USS Powhatan. http://www.marylandsilver.com/Ship.htm
I´m going to order them next month so that maybe by the end of the year I can start building. I looked at the above mentioned website about the cannons but the owner has apparently passed away. (Which I am sorry to hear) Does anyone know of anybody else that makes them. They look fantastic. I have been looking all over for 1/96 scale IX Dahlgrens and 150 Parrotts and can´t find any.
Here is another really good view of the Susqy.
http://ocw.mit.edu/ans7870/21f/21f.027/black_ships_and_samurai/cross01_a.html
I have also bought a 1/150 scale Aoshima USS Susquehanna that I want to use as a reference. I found one from a seller in Hong Kong and it is also (hopefully) underway. Can´t wait for it to get here. Maybe in about 2 years. Ha Ha.
Bill