A crj-700 flight crew departed lga in the dg (directional gyro) mode. When airborne the captain and ...

Attributes
ACN	980110
Time
Date	201111
Local Time Of Day	1201-1800
Place
Locale Reference	N90.TRACON
State Reference	NY
Aircraft 1
Make Model Name	Regional Jet 700 ER/LR (CRJ700)
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	AHRS/ND
Person 1
Function	Pilot Flying First Officer
Qualification	Flight Crew Commercial
Person 2
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	ATC Issue All Types Aircraft Equipment Problem Critical Deviation - Track / Heading All Types Flight Deck / Cabin / Aircraft Event Other / Unknown

Narrative:

On takeoff from runway 13 in dg mode; both pfds were properly aligned. While on the white stone departure; no problems on first turn 180 degrees. No problems on second turn 040 degrees. Prior to the third turn we got heading and EFIS comparators on captain's side which lead us to believe that my side was good because there was no alert on my pfd. The captain tried to fix his by going to magnetic mode while holding a steady 250K but was unsuccessful. He then went back to dg to try and realign. On our third turn ATC asked where we were going; we stated we were 20 degrees left of course. I then lost my flight director and course line and we received heading and magnetic warnings. We asked ATC to remain on current heading; altitude; and airspeed of 250K. Our pfds were over 50 degrees apart and we were unable to navigate to a fix. I maintained 15000 MSL straight and level at 250K. With both pfds in dg mode; we slewed both to 250 degrees; as this was our approximate heading. We then engaged magnetic mode and resumed normal flight.

Original NASA ASRS Text

Title: A CRJ-700 Flight Crew departed LGA in the DG (Directional Gyro) mode. When airborne the Captain and First Officer headings diverged and track deviations ensued. Ultimately the headings were aligned and MAG AHRS/EFIS guidance engaged and the flight continued normally.

Narrative: On takeoff from Runway 13 in DG mode; both PFDs were properly aligned. While on the White Stone Departure; no problems on first turn 180 degrees. No problems on second turn 040 degrees. Prior to the third turn we got HDG and EFIS Comparators on Captain's side which lead us to believe that my side was good because there was no alert on my PFD. The Captain tried to fix his by going to MAG Mode while holding a steady 250K but was unsuccessful. He then went back to DG to try and realign. On our third turn ATC asked where we were going; we stated we were 20 degrees left of course. I then lost my Flight Director and course line and we received HDG and MAG warnings. We asked ATC to remain on current heading; altitude; and airspeed of 250K. Our PFDs were over 50 degrees apart and we were unable to navigate to a fix. I maintained 15000 MSL straight and level at 250K. With both PFDs in DG mode; we slewed both to 250 degrees; as this was our approximate heading. We then engaged MAG mode and resumed normal flight.

Data retrieved from NASA's ASRS site as of April 2012 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.

A crj-700 flight crew departed lga in the dg (directional gyro) mode. When airborne the captain and first officer headings diverged and track deviations ensued. Ultimately the headings were aligned and magnetic ahrs/EFIS guidance engaged and the flight continued normally.