Re: Flights from US East Coast to Caribbean charter destinations
You have to be creative with this.
Fly out of Atlantic City on Spirit. That can get you to San Juan, St Thomas or St Martin. Its Spirit.com
Once you're on island you can do Liat, American Eagle or charter from St Martin to your final destination. I did a quick search from ACY to SJU and it was $206 each way.
Good Luck and enjoy!