Altitude deviation altitude overshot in descent.

Attributes
ACN	317500
Time
Date	199510
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sfo
State Reference	CA
Altitude	msl bound lower : 3700 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sfo tower : ord
Operator	common carrier : air carrier
Make Model Name	MD-80 Super 80
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach descent other
Route In Use	approach : visual enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
ASRS Report	317500
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	317587
Events
Anomaly	altitude deviation : crossing restriction not met altitude deviation : overshoot non adherence : clearance non adherence : published procedure other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : anomaly accepted
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While flying quiet bridge visual sfo, descended below 4000 ft at 13 DME fix. Deviation occurred due to crew's search for parallel traffic inbound to runway 28L. At 12 DME we were at 3700 ft. Supplemental information from acn 317587: I was flying the quiet bridge visual to runway 28R at sfo in beautiful WX. At about 15 DME we were advised of VFR traffic ahead and below us and told to slow to 180. While slowing, looking for the VFR traffic, and monitoring the aircraft to our left on approach to runway 28L, approach control asked if we were following the altitudes for the approach. As we were at 3700 ft at 12 DME we responded affirmatively.

Original NASA ASRS Text

Title: ALTDEV ALT OVERSHOT IN DSCNT.

Narrative: WHILE FLYING QUIET BRIDGE VISUAL SFO, DSNDED BELOW 4000 FT AT 13 DME FIX. DEV OCCURRED DUE TO CREW'S SEARCH FOR PARALLEL TFC INBOUND TO RWY 28L. AT 12 DME WE WERE AT 3700 FT. SUPPLEMENTAL INFO FROM ACN 317587: I WAS FLYING THE QUIET BRIDGE VISUAL TO RWY 28R AT SFO IN BEAUTIFUL WX. AT ABOUT 15 DME WE WERE ADVISED OF VFR TFC AHEAD AND BELOW US AND TOLD TO SLOW TO 180. WHILE SLOWING, LOOKING FOR THE VFR TFC, AND MONITORING THE ACFT TO OUR L ON APCH TO RWY 28L, APCH CTL ASKED IF WE WERE FOLLOWING THE ALTS FOR THE APCH. AS WE WERE AT 3700 FT AT 12 DME WE RESPONDED AFFIRMATIVELY.

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.