I think Avelo is the only airline that participates. The rest are charter companies.

It is likely that many airlines accommodate people who are being deported as regular passengers on outbound international flights.

For movement of humans at industrial scale, though, there are only a few operators with ICE contracts. Avelo, GlobalX, Eastern, Key Lime Air, and Omni come immediately to mind. For international flights, there's at least one Learjet operator that flies a bunch for them, too.

These days, the aforementioned carriers fly 20-30 flights/day. Here are Saturday's flights (apologies for the sign-in wall, but lalabote keeps their account somewhat locked down): https://bsky.app/profile/lalabote.bsky.social/post/3mai6lach...

Whoops -- was away from HN for a few days.

Here is JJ's account -- he is a prolific flight-tracker: https://bsky.app/profile/jjindc.bsky.social

Here is an Avelo flight moving through California right now: https://bsky.app/profile/jjindc.bsky.social/post/3malkyew432...

Here is an Avelo flight on the ground in Seattle on Saturday: https://bsky.app/profile/jjindc.bsky.social/post/3magxcnri32...

Avelo flies a number of flights each week for ICE.