Date: 202106
Local time of day: 1201-1800
Location: ORD.Airport, IL
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Landing
Airspace: Class B ORD
ATC / advisory: Tower ORD
Reporter organization: Air Carrier
Reporter function: Pilot Flying; First Officer
Reporter qualification: Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Human factors: Other / Unknown
Second reporter function: Captain; Pilot Not Flying
Anomaly: ATC Issue All Types; Ground Event / Encounter Jet Blast; Inflight Event / Encounter Other / Unknown
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Regained Aircraft Control
Contributing factors: Aircraft; Airport; ATC Equipment / Nav Facility / Buildings
Primary problem: Airport

Narrative: On approach into [Runway] [27C] in Chicago it was by all accounts a normal day. A storm had passed about 2 hours prior giving way to the benign conditions usually experienced after the passing of a storm. The wind was hardly noticeable I had nearly no crosswind correction in on the approach. As we approached the final approach fix Tower cleared a 777 to cross our landing runway. We continued; the aircraft was fully across the runway by the time we reached 1;000 feet AGL and parked on Taxiway TT. I assume he was waiting for a clearance from Ground to continue further. We continued on the approach and right as I was bringing the thrust levers back to idle a sudden jolt of firm left aileron and right rudder were needed to continue a safe ground track and land the aircraft. I am not sure exactly what bank angle was achieved but the proximity to the ground made it seem like quite a lot. My guess is around 10-12 degrees of bank at 10 feet off the ground. Some comments from passengers sounding the alarm that things where not correct when they got off the airplane make me think things where perhaps worse than I know due to the speed at which this all happened. The incident all happened approximately 10 ft AGL. Due to the suddenness and nature of the incident the best course of action was to land the aircraft. I had plenty of runway available to safely execute a full stop landing. Had the event happened at say 50 or 100 feet; a go-around would have certainly been necessary. The landing overall was completed without further incident. We taxied to gate; deplaned. And other than a few comments from Flight Attendants and passengers it was a normal operation. The cause of this sudden change and necessity for rudder and aileron was due to the 777 parked on Taxiway TT attempting to taxi right as I was landing. He was headed out for takeoff so I assume he was all loaded up and needed a lot of thrust to get moving. This is what caused such a dramatic necessity for correction very close to the ground. I hope out of this pilots and Controllers are made aware of the possibility of incidents like this in the future if we're not operationally prepared in some way. The cause of the event was the new taxi procedures and runway configuration due to the addition of 27C in Chicago. When cargo carriers taxi on TT they're putting anyone landing at risk of jet blast. At least a note could be added to our company pages alerting pilots about the possibility of this happening. But maybe even a change in how Chicago does taxi operations.


Second narrative: There is a significant safety threat to aircraft landing on Runway 27C in ORD; due to jet blast from aircraft crossing 27C on taxiway TT.  This taxiway is approximately 1;100 - 1;200 feet from the departure end; so it is perfectly situated to impact aircraft in the landing flare.  To make matters worse; aircraft that cross 27C are instructed to contact Ground on TT and are therefore not on frequency when given an instruction to continue their taxi. In this particular case; a 777 had crossed 27C; then stopped on TT; presumably awaiting further taxi instructions from Ground.  They were not on our frequency.  At under 10 feet we were hit with a really bad amount of jet blast from the 777.  The First Officer did a fantastic job of getting the roll event back under control for a safe touchdown.  We advised Tower of the event. Something with regard to the above needs to change.  Either; aircraft should cross somewhere else; Controllers should advise aircraft crossing 27C at TT to use minimal power when resuming taxi; Controllers advise pilots of the jet blast potential; or at the very least; there should be a note on a chart.


Synopsis: B737 flight crew reported encountering jet blast from B777 on Taxiway TT while landing on ORD RWY 27C.