Help ID New England (MA) bird.?

Question

I am a birder but have not seen this bird. They were flyign at 6pm higher, and in a group. they were randomly flyign in circles and looked at first like swallows. They seems to have a forked tail, but were bigger than swallows. They also had a distinct half moon shaped wings (like a chinmey swift) and a very noticeable white almost stripe marking underneath each wing). looked like a big swift but not sure. they circles randomly for about 5 minutes and moved on?

Answer 1

What you describe sounds like a night hawk or bull bat. They circle in the sky at evening. They eat insects and mostly mosquitoes.

Answer 2

i live right above ya in New Hampshire.

Answer 3

I would guess that these are Common Nighthawks..they do have a distinct stripe under each wing  and they do range into MA.

http://www.flickr.com/photos/colonial163...

Answer 4

They could have been "Terns" on migratory flight.

Just a guess.