DC9 crew had altitude overshoot in phl class east.

Attributes
ACN	484430
Time
Date	200009
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : lrp.vortac
State Reference	PA
Altitude	msl bound lower : 7700 msl bound upper : 8000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : phl.tracon
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	descent : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : cfi pilot : flight engineer
Experience	flight time last 90 days : 210 flight time total : 9000 flight time type : 1000
ASRS Report	484430
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : commercial pilot : cfi pilot : atp
Experience	flight time last 90 days : 150 flight time total : 5400 flight time type : 350
ASRS Report	484703
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : overshoot inflight encounter : weather inflight encounter other non adherence : company policies non adherence : published procedure non adherence : clearance other anomaly other
Independent Detector	aircraft equipment : altitude alert other flight crewa other flight crewb
Resolutory Action	flight crew : returned to assigned altitude none taken : detected after the fact
Consequence	other
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance Weather
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

First officer was PF (using autoplt). Cleared to descend to 8000 ft. Deviating slightly around build-ups diverted our attention. Despite 'altitude awareness' callouts, the altitude reached almost 7700 ft before corrective action was taken back to 8000 ft. ATC made no mention of the event. In future will avoid doing anything else during last 1000 ft of climb/descent. Supplemental information from acn 484703: as PF (autoplt engaged) we were leveling off at 8000 ft. Deviating around severe WX. Aircraft continued to descend through 8000 ft to approximately 7700 ft. The altitude alerter signaled and corrective action was immediately taken. No conflicts occurred, and ATC was not affected. I believe the primary cause was autoplt failure to capture desired altitude, also high workload while deviations around WX were factors, despite altitude crew awareness program.

Original NASA ASRS Text

Title: DC9 CREW HAD ALT OVERSHOOT IN PHL CLASS E.

Narrative: FO WAS PF (USING AUTOPLT). CLRED TO DSND TO 8000 FT. DEVIATING SLIGHTLY AROUND BUILD-UPS DIVERTED OUR ATTN. DESPITE 'ALT AWARENESS' CALLOUTS, THE ALT REACHED ALMOST 7700 FT BEFORE CORRECTIVE ACTION WAS TAKEN BACK TO 8000 FT. ATC MADE NO MENTION OF THE EVENT. IN FUTURE WILL AVOID DOING ANYTHING ELSE DURING LAST 1000 FT OF CLB/DSCNT. SUPPLEMENTAL INFO FROM ACN 484703: AS PF (AUTOPLT ENGAGED) WE WERE LEVELING OFF AT 8000 FT. DEVIATING AROUND SEVERE WX. ACFT CONTINUED TO DSND THROUGH 8000 FT TO APPROX 7700 FT. THE ALT ALERTER SIGNALED AND CORRECTIVE ACTION WAS IMMEDIATELY TAKEN. NO CONFLICTS OCCURRED, AND ATC WAS NOT AFFECTED. I BELIEVE THE PRIMARY CAUSE WAS AUTOPLT FAILURE TO CAPTURE DESIRED ALT, ALSO HIGH WORKLOAD WHILE DEVS AROUND WX WERE FACTORS, DESPITE ALT CREW AWARENESS PROGRAM.

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.