One way door for a pigeon coop ?

i THINK ( really dont hve a clue) but i think the door is attached at the top ( so that its like old salon doors, just up and down instead of sideways)and theres a board that runs along the bottom on the outside,, that way,, you can push the door "in" from the outside,, but comming out, the bottom of the door hits that outside board,thus not allowing it to be pushed "out" from the inside.
i think,
probably not' not really even close,
hehe

it coudl be the way he ^^^ said it or I was thinking it might be like lobster and quail traps...wide funnel entrence, but small exit so small the birds can't figure out how to get out once they're in

I actually know the answer to this as I just got pigeons and asked this question a while ago...first why do you want it? After my bear attack (see post in predators) Unless it was for racing I do not believe you need it and I will always want my birds to be able to get out.
It looks like a large metal comb the teeth allow the bird in but it can not get back out becaus eit hits the door frame.
Search for: pigeon door, they are also used to trap birds
Hope that helps

Call a trap door,  go to www.jedds.com  they have several type about 20.00 and up

These can save alot of birds. All racer use them, but any pigeon can use them. Let your birds out when they go back in. no worry about hawks getting them. Bird setting on outbuilding are easy prey.

  They must be close at night, landing board act as a door to close off the trap. I forgot one night, yep coon use the trap door. could not get out ,but lost a few birds.

"They must be close at night, landing board act as a door to close off the trap. I forgot one night, yep coon use the trap door. could not get out ,but lost a few birds."

Yes but you could have lost less if they could have gotten out...??

Nope you ever go into a loft at night. you can pick them up off the roost without the one next to it even moving!
 
Most will stay on the roost as a coon is eating one.

best to keep them locked up at night.  and KEEP the critters locked out.    Remember if the bird can get out the predators can get in. Why have them fly out, to all the night predators, owls,coons and etc. the birds cant see at night but those nightcritter CAN.

ya thats right!!,, i watched my cats 1 night climb a tree and grab a dove,,,, and the 4 or 5 doves next to them acted like they had NO idea what was going on,,,,,i screamed at the cat,,and walked over and PICKED the doves off the roost.