CL65 crew had autoplt flight control problems on approach at bwi.

Attributes
ACN	502360
Time
Date	200102
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : bwi.airport
State Reference	MD
Altitude	msl single value : 2500
Environment
Flight Conditions	IMC
Weather Elements	Ice Turbulence other
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : bwi.tracon
Operator	common carrier : air carrier
Make Model Name	Regional Jet 200 ER&LR
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 10 other
Flight Phase	descent : approach
Route In Use	approach : instrument precision arrival : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : student pilot : private pilot : instrument pilot : commercial pilot : multi engine
Experience	flight time last 90 days : 100 flight time total : 700 flight time type : 400
ASRS Report	502360
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : critical altitude deviation : overshoot inflight encounter : turbulence inflight encounter : weather inflight encounter other non adherence : clearance other anomaly other anomaly other
Independent Detector	aircraft equipment : gpws other flight crewa other flight crewb
Resolutory Action	controller : issued alert controller : issued new clearance flight crew : executed go around none taken : detected after the fact other
Supplementary
Problem Areas	Flight Crew Human Performance Weather Aircraft ATC Human Performance
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation
Situations
ATC Facility	procedure or policy : bwi.tracon

Narrative:

The following describes the sequence of events that led to a botched approach and a resulting missed approach. We were being radar vectored for the ILS 10 in bwi from the northwest. There was a cold front moving through the area, and we had experienced strong winds both on the surface and at altitude all day. ATC gave us the clearance, 'fly heading 120 degrees, maintain 2500 ft until established, 170 until 4 DME, cleared for the ILS 10 approach.' at 2500 ft, winds were sse at 60 KTS. Due to the shallow vector intercept and the winds aloft at the time, we did not capture the localizer course until inside collum. The autoplt captured the localizer course. However, the GS was 1/2 scale below -- we were still at 2500 ft. 1500 ft was selected on the altitude select, and a descent of 1000 FPM down was selected to capture the GS. Within a few seconds, the autoplt captured the GS and pitched the aircraft down over 12 degrees to capture the GS. We received a 'sink rate' GPWS message. I disconnected the autoplt to arrest the descent rate. At this point, we were off GS and straying off localizer. I disconnected the autoplt and executed a missed approach at 800 ft. ATC assigned runway heading. At 1800 ft, ATC assigned 'maintain 2000 ft.' 2500 ft was set in the altitude preselect, and we were climbing at 4300 FPM. I selected 'altitude' to arrest the ascent rate and level at 2000 ft. However, due to the nature of the autoplt which was on at this point, the aircraft climbed to 2800 ft before it gradually lowered the nose to level and then even further to descend. Approach was yelling at us, so I disconnected the autoplt again and pitched down to reacquire 2000 ft. We were vectored back around for another approach and landed without any further incident. Contributing factors: 1) poor awareness of winds aloft by both us and the controller giving the vectors, 2) reluctance on our part to go missed immediately and not salvage the botched approach, 3) ATC assigning a lower altitude to maintain while we were too quickly en route to the published missed altitude.

Original NASA ASRS Text

Title: CL65 CREW HAD AUTOPLT FLT CTL PROBS ON APCH AT BWI.

Narrative: THE FOLLOWING DESCRIBES THE SEQUENCE OF EVENTS THAT LED TO A BOTCHED APCH AND A RESULTING MISSED APCH. WE WERE BEING RADAR VECTORED FOR THE ILS 10 IN BWI FROM THE NW. THERE WAS A COLD FRONT MOVING THROUGH THE AREA, AND WE HAD EXPERIENCED STRONG WINDS BOTH ON THE SURFACE AND AT ALT ALL DAY. ATC GAVE US THE CLRNC, 'FLY HDG 120 DEGS, MAINTAIN 2500 FT UNTIL ESTABLISHED, 170 UNTIL 4 DME, CLRED FOR THE ILS 10 APCH.' AT 2500 FT, WINDS WERE SSE AT 60 KTS. DUE TO THE SHALLOW VECTOR INTERCEPT AND THE WINDS ALOFT AT THE TIME, WE DID NOT CAPTURE THE LOC COURSE UNTIL INSIDE COLLUM. THE AUTOPLT CAPTURED THE LOC COURSE. HOWEVER, THE GS WAS 1/2 SCALE BELOW -- WE WERE STILL AT 2500 FT. 1500 FT WAS SELECTED ON THE ALT SELECT, AND A DSCNT OF 1000 FPM DOWN WAS SELECTED TO CAPTURE THE GS. WITHIN A FEW SECONDS, THE AUTOPLT CAPTURED THE GS AND PITCHED THE ACFT DOWN OVER 12 DEGS TO CAPTURE THE GS. WE RECEIVED A 'SINK RATE' GPWS MESSAGE. I DISCONNECTED THE AUTOPLT TO ARREST THE DSCNT RATE. AT THIS POINT, WE WERE OFF GS AND STRAYING OFF LOC. I DISCONNECTED THE AUTOPLT AND EXECUTED A MISSED APCH AT 800 FT. ATC ASSIGNED RWY HDG. AT 1800 FT, ATC ASSIGNED 'MAINTAIN 2000 FT.' 2500 FT WAS SET IN THE ALT PRESELECT, AND WE WERE CLBING AT 4300 FPM. I SELECTED 'ALT' TO ARREST THE ASCENT RATE AND LEVEL AT 2000 FT. HOWEVER, DUE TO THE NATURE OF THE AUTOPLT WHICH WAS ON AT THIS POINT, THE ACFT CLBED TO 2800 FT BEFORE IT GRADUALLY LOWERED THE NOSE TO LEVEL AND THEN EVEN FURTHER TO DSND. APCH WAS YELLING AT US, SO I DISCONNECTED THE AUTOPLT AGAIN AND PITCHED DOWN TO REACQUIRE 2000 FT. WE WERE VECTORED BACK AROUND FOR ANOTHER APCH AND LANDED WITHOUT ANY FURTHER INCIDENT. CONTRIBUTING FACTORS: 1) POOR AWARENESS OF WINDS ALOFT BY BOTH US AND THE CTLR GIVING THE VECTORS, 2) RELUCTANCE ON OUR PART TO GO MISSED IMMEDIATELY AND NOT SALVAGE THE BOTCHED APCH, 3) ATC ASSIGNING A LOWER ALT TO MAINTAIN WHILE WE WERE TOO QUICKLY ENRTE TO THE PUBLISHED MISSED ALT.

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.