It happened at the 125th Street 4-5-6 train station at 3:55 p.m. Friday.
A straphanger ran up from the station screaming for help because somebody had fallen onto the tracks.
Two NYPD officers, an MTA worker and several civilians rushed to the man's aid.
The cops were on the platform while the MTA worker, Carlos Betancourt, and civilians jumped onto the tracks to help the 50-year-old Jerome Billings up.
The man fell from an area of the platform right near where a train would be rounding the corner to pull into the station.
Billings' coat sleeve got caught on the controller of his motorized wheelchair, causing him to lose control.
The cops waived their flashlight to maker sure an oncoming conductor would see them and stop.
It took a couple of minutes to pull Billings up from the tracks.
EMS transported the man to NY Presbyterian Cornell Medical Center where he's listed in stable condition.