CRJ700 first officer reported that an FMS malfunction resulted in an altitude and course deviation.

Attributes
ACN	1737183
Time
Date	202003
Local Time Of Day	1801-2400
Place
Locale Reference	PCT.TRACON
State Reference	VA
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	Regional Jet 700 ER/LR (CRJ700)
Operating Under FAR Part	Part 121
Flight Phase	Descent
Flight Plan	IFR
Person 1
Function	Pilot Flying First Officer
Qualification	Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Altitude Overshoot Deviation - Procedural Clearance Deviation - Track / Heading All Types Inflight Event / Encounter Wake Vortex Encounter

Narrative:

While descending on the GIBBZ3 we were assigned by ATC to cross and maintain 6;000 ft. At gibbz but while leveling off at 6;000 ft. We encountered wake from another aircraft and the autopilot continued descending through 6;000 ft. And I caught it and stopped it. The captain stated he would write it up with maintenance for being a faulty autopilot. Also moments later while on the GIBBZ3 arrival over sunyj while initially setup for runway 19C; we were told to switch to runway 19R (the overflow runway) as the controller indicated it would be much faster for us. While setting up the FMS for runway 19R the captain stated that our FMS briefly 'blacked out' on him which left us briefly in heading mode; as opposed to (FMS mode) following the depicted track on the GIBBZ3 arrival to udiyu and mattc. The controller vectored us back onto the arrival with two headings and we agreed it would be best fill out a report for what appeared to be a faulty FMS and faulty autopilot.

Original NASA ASRS Text

Title: CRJ700 First Officer reported that an FMS malfunction resulted in an altitude and course deviation.

Narrative: While descending on the GIBBZ3 we were assigned by ATC to cross and maintain 6;000 ft. at GIBBZ but while leveling off at 6;000 ft. we encountered wake from another aircraft and the autopilot continued descending through 6;000 ft. and I caught it and stopped it. The Captain stated he would write it up with Maintenance for being a faulty autopilot. Also moments later while on the GIBBZ3 arrival over SUNYJ while initially setup for Runway 19C; we were told to switch to Runway 19R (the overflow runway) as the Controller indicated it would be much faster for us. While setting up the FMS for Runway 19R the Captain stated that our FMS briefly 'blacked out' on him which left us briefly in HDG Mode; as opposed to (FMS Mode) following the depicted track on the GIBBZ3 arrival to UDIYU and MATTC. The Controller vectored us back onto the arrival with two headings and we agreed it would be best fill out a report for what appeared to be a faulty FMS and faulty autopilot.

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.