Crj-900 first officer reported a track deviation occurred following a wake turbulence encounter appr...

Attributes
ACN	1556494
Time
Date	201807
Local Time Of Day	1801-2400
Place
Locale Reference	PHX.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Regional Jet 900 (CRJ900)
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Route In Use	STAR EAGUL 6
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Plan	IFR
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Instrument Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine
Events
Anomaly	ATC Issue All Types Deviation - Procedural Clearance Deviation - Track / Heading All Types Inflight Event / Encounter Wake Vortex Encounter

Narrative:

While being routed in sequence for the EAGUL6 arrival into phx our aircraft was experiencing severe wake turbulence with banks between 30 and 45 degrees. After two occurrences; we requested ATC for an offset to avoid the wake of the leading aircraft. ATC instructed us to offset to the north and continue the arrival. The captain and I verified the instruction to offset to the north and continue the arrival. As pilot flying; I put the autopilot in heading mode and set the heading 15 degrees to the right while the captain programmed the FMS for the north offset by 5 miles. We verified the programming with each other and I placed the autopilot in navigation mode to resume the arrival. Two or three minutes later; ATC said that he instructed us to offset by only one mile and gave us a new clearance to join the BRUSR1 arrival. The captain and I reviewed the sequence of events; and neither of us recalled hearing or reading back the instructions to include an offset of one mile. No other issues arose and ATC gave no other feedback regarding the instructions or our actions.in hindsight; we may have verified the instructions given to us by ATC although we were unaware of the possible error in the delivery or read back of the instructions.

Original NASA ASRS Text

Title: CRJ-900 First Officer reported a track deviation occurred following a wake turbulence encounter approaching PHX.

Narrative: While being routed in sequence for the EAGUL6 arrival into PHX our aircraft was experiencing severe wake turbulence with banks between 30 and 45 degrees. After two occurrences; we requested ATC for an offset to avoid the wake of the leading aircraft. ATC instructed us to offset to the north and continue the arrival. The Captain and I verified the instruction to offset to the north and continue the arrival. As pilot flying; I put the autopilot in heading mode and set the heading 15 degrees to the right while the Captain programmed the FMS for the north offset by 5 miles. We verified the programming with each other and I placed the autopilot in NAV mode to resume the arrival. Two or three minutes later; ATC said that he instructed us to offset by only one mile and gave us a new clearance to join the BRUSR1 arrival. The Captain and I reviewed the sequence of events; and neither of us recalled hearing or reading back the instructions to include an offset of one mile. No other issues arose and ATC gave no other feedback regarding the instructions or our actions.In hindsight; we may have verified the instructions given to us by ATC although we were unaware of the possible error in the delivery or read back of the instructions.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Crj-900 first officer reported a track deviation occurred following a wake turbulence encounter approaching phx.