Emb-145 flight crew reported an altitude deviation occurred after encountering wake turbulence on ar...

Attributes
ACN	1613267
Time
Date	201901
Local Time Of Day	1801-2400
Place
Locale Reference	ORD.Airport
State Reference	IL
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	EMB ERJ 145 ER/LR
Operating Under FAR Part	Part 121
Flight Phase	Descent
Route In Use	STAR MADII FOUR
Flight Plan	IFR
Aircraft 2
Make Model Name	Heavy Transport
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Route In Use	STAR MADII
Flight Plan	IFR
Person 1
Function	Captain Pilot Not Flying
Qualification	Flight Crew Instrument Flight Crew Air Transport Pilot (ATP) Flight Crew Multiengine
Experience	Flight Crew Total 5830
Person 2
Function	Pilot Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Events
Anomaly	Deviation - Altitude Excursion From Assigned Altitude Inflight Event / Encounter Wake Vortex Encounter

Narrative:

On flight to ord air traffic control advised first officer and I of a heavy aircraft ahead and 1;000 ft above our assigned altitude. I reported aircraft in sight. As the other aircraft appeared closer and closer on TCAS I had the flight attendant sit down for possible wake turbulence. While on the madii 4 arrival somewhere after soolu ATC told us to descend [to] 7;000 ft. While slowing in order to descend we encountered a wake; losing about 100 ft than gaining 150 ft but no more than 200 feet. After the encounter I asked ATC for a heading to aid in reestablish on the arrival. He gave us a heading of 090 and we descended to 7;000 ft and complied with new assigned heading. At no point did the aircraft [TCAS] give any type of proximity caution / warning. Would like more distance between heavy aircraft.

Original NASA ASRS Text

Title: EMB-145 flight crew reported an altitude deviation occurred after encountering wake turbulence on arrival into ORD in trail of a heavy aircraft.

Narrative: On flight to ORD air traffic control advised First Officer and I of a heavy aircraft ahead and 1;000 ft above our assigned altitude. I reported aircraft in sight. As the other aircraft appeared closer and closer on TCAS I had the flight attendant sit down for possible wake turbulence. While on the MADII 4 Arrival somewhere after SOOLU ATC told us to descend [to] 7;000 ft. While slowing in order to descend we encountered a wake; losing about 100 ft than gaining 150 ft but no more than 200 feet. After the encounter I asked ATC for a heading to aid in reestablish on the arrival. He gave us a heading of 090 and we descended to 7;000 ft and complied with new assigned heading. At no point did the aircraft [TCAS] give any type of proximity caution / warning. Would like more distance between heavy aircraft.

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.

Emb-145 flight crew reported an altitude deviation occurred after encountering wake turbulence on arrival into ord in trail of a heavy aircraft.