On Friday, October 20, 2017 at 10:48:26 AM UTC-5, Steve Koerner wrote:
On Friday, October 20, 2017 at 3:51:04 AM UTC-7, wrote:
The official report does not provide any additional information.

http://www.asias.faa.gov/pls/apex/f?...R:NGLTRFD17001

Are we never going to know if this glider had a transponder?
Can someone who flies in the Chicago area please try to sort this out?

It's pretty clear that the glider either didn't have a transponder or it was turned off. If the glider had an operating transponder, it would have been visible on ATC radar, and the UA jet would have presumably been vectored around the glider or at least have received a traffic advisory from ATC (even though this is not required by the FAA rules).

If ATC hadn't vectored the UA jet around the glider, a transponder would have triggered a TCAS Resolution Advisory which would have resolved the situation and avoided the aircraft getting this close to each other. There is no indication in the report that the UA aircraft received a TCAS RA, which would indicate that the glider did not have an operating transponder.