DC9 crew had altitude overshoot while flying a missed approach after compass failure.

Attributes
ACN	569768
Time
Date	200301
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : bwi.airport
State Reference	MD
Altitude	msl bound lower : 2000 msl bound upper : 2500
Environment
Flight Conditions	IMC
Weather Elements	Fog
Light	Daylight
Aircraft 1
Controlling Facilities	tower : bwi.tower
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude landing : missed approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 10000 flight time type : 2000
ASRS Report	569768
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : overshoot inflight encounter : weather non adherence : published procedure non adherence : company policies non adherence : far other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : rmi compass auto plt other flight crewa other flight crewb
Resolutory Action	controller : provided flight assist controller : issued new clearance flight crew : executed missed approach
Consequence	other
Supplementary
Problem Areas	Flight Crew Human Performance Weather Aircraft
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

Approach control vectored us to a 9 mi final. WX at bwi 1 mi fix 4 mi overcast 1 SM plus rain. We were told to maintain 190 KIAS to 5 mi. I elected to begin configuring at 8 mi to be stabilized by 5 mi (OM is at 5.1 DME for runway 10.0). The autoplt intercepted the localizer at about 8 DME and during the turn to final, the #2 RMI rotated about 30 degrees left. This caused the autoplt to follow and it lost the lock on the localizer. I clicked off the autoplt and requested a no gyro missed approach because we didn't know which heading system was bad. During the missed approach, we cleared to 2000 ft MSL but we climbed through to 2500 ft before we arrested the climb. This altitude deviation was caused by me being preoccupied with trying to determine which heading system was bad. While receiving no gyro vectors, we determined what the problem was and had the first officer hand fly an ILS to runway 10.

Original NASA ASRS Text

Title: DC9 CREW HAD ALT OVERSHOOT WHILE FLYING A MISSED APCH AFTER COMPASS FAILURE.

Narrative: APCH CTL VECTORED US TO A 9 MI FINAL. WX AT BWI 1 MI FIX 4 MI OVCST 1 SM PLUS RAIN. WE WERE TOLD TO MAINTAIN 190 KIAS TO 5 MI. I ELECTED TO BEGIN CONFIGURING AT 8 MI TO BE STABILIZED BY 5 MI (OM IS AT 5.1 DME FOR RWY 10.0). THE AUTOPLT INTERCEPTED THE LOC AT ABOUT 8 DME AND DURING THE TURN TO FINAL, THE #2 RMI ROTATED ABOUT 30 DEGS L. THIS CAUSED THE AUTOPLT TO FOLLOW AND IT LOST THE LOCK ON THE LOC. I CLICKED OFF THE AUTOPLT AND REQUESTED A NO GYRO MISSED APCH BECAUSE WE DIDN'T KNOW WHICH HDG SYS WAS BAD. DURING THE MISSED APCH, WE CLRED TO 2000 FT MSL BUT WE CLBED THROUGH TO 2500 FT BEFORE WE ARRESTED THE CLB. THIS ALTDEV WAS CAUSED BY ME BEING PREOCCUPIED WITH TRYING TO DETERMINE WHICH HDG SYS WAS BAD. WHILE RECEIVING NO GYRO VECTORS, WE DETERMINED WHAT THE PROB WAS AND HAD THE FO HAND FLY AN ILS TO RWY 10.

Data retrieved from NASA's ASRS site as of July 2007 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.