Boeing 737-522 N941UA

Summary

On 28 December 2001 at about 20:31 local time, a Boeing 737-522 registered N941UA was involved in an incident near Chicago, Illinois, United States. 104 people were on board and nobody was injured. No probable cause statement is available for this record.

Date

28 December 2001 at 20:31

Classification

Incident

Location

Chicago, Illinois, United States

Nearest airport

Chicago O'Hare International (ORD)

Coordinates

41.9797, -87.9044

Aircraft

Boeing 737-522

Registration

N941UA

Category

Airplane

Engines

2

Operator

Not recorded

Operating rule

Part 121: Air Carrier

Phase of flight

Not recorded

Route

Cedar Rapids → Chicago

Aircraft damage

Not recorded

Weather

VMC

Light

Day

NTSB number

CHI02IA058

Nobody was injured.

The NTSB has not published a probable cause for this record. No probable cause statement is present in the source data.

Nothing about the cause is stated here that is not in the source record.

Read the full NTSB narrative

The Boeing 737 airplane encountered wake turbulence during cruise descent. The captain reported the aircraft was descending from 10,000 feet mean sea level (msl) when he noticed a "subtle vibration" that was followed by the airplane entering an uncommanded roll to the right. The captain reported that he disconnected the autopilot system at approximately 20 degrees right roll, and he regained control of the aircraft using manual control inputs of left rudder and left aileron. The captain stated that he had "complete usage of the rudder" during the recovery. The flightcrew declared an emergency and made an uneventful landing. Aircraft radar track data indicated the incident airplane (UAL Flt 1260) was following a Boeing 777, operated by American Airlines as flight 154 (AAL Flt 154). Both aircraft were en route to Chicago O'Hare International Airport and were flying the same arrival procedure. Both airplanes were maintaining a lateral separation of approximately 8.3 nm or about 97 seconds. AAL Flt 154 began its descent 12.56 nm from KRENA intersection, and 23 seconds later UAL Flt 1260 began its descent 6.23 nm from the intersection. During the uncommanded roll and subsequent recovery, all rudder control surface movements correlated with the position of the rudder pedals. No flight control anomalies were found during the post-incident examination and verification flight test.

Quoted verbatim from the NTSB record.