There are no helicopters stationed at Charity Hospital and there is no heliport on top of the hosiptal. Helicopters usually land at the New Orleans Downtown Heliport next to the Superdome when transporting patients to Charity Hospital and other hospitals in the vicinity.
Although Acadian promised to station a helicopter in New Orleans when they took over Priority EMS in 2/2004, they have still not placed one in the area. The closet Acadian helicopter is currently stationed in Slidell.
Acadian's frequencies were listed in this thread:
http://www.radioreference.com/modules.php?name=Forums&file=viewtopic&t=3608 . I included a few corrections below:
F-1 155.280
F-2 155.205
F-3 155.220
F-4 155.340
F-5 155.295
F-6 155.235
FREQ PARISHES
1 EVANGELINE , ST. LANDRY
5 RAPIDES , AVOYELLES
2 ACADIA , LAFAYETTE , ST. MARTIN , VERMILLION , IBERIA
5 ASCENSION , ST. JOHN THE BAPTIST , ST. JAMES, ASSUPTION , ST. MARY , TERREBONNE , LAFOURCHE, ST. CHARLES
2 JEFFERSON , ORLEANS , PLAQUEMINES, ST. BERNARD
3 EAST AND WEST FELICIANA , POINTE COUPEE ,
3 IBERVILLE , LIVINGSTON , EAST AND WEST BATON ROUGE
3 JEFF DAVIS , CALCASIEU , BEAUREGUARD , VERNON , ALLEN
6 ST. HELENA , TANGIPAHOA , ST. TAMMANY