Air carrier widebody transport departed altitude on approach prior to reaching proper fix.

Attributes
ACN	97611
Time
Date	198811
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mia
State Reference	FL
Altitude	msl bound lower : 2100 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : mia
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	approach : straight in
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 80 flight time total : 2200 flight time type : 85
ASRS Report	97611
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 70 flight time total : 12000 flight time type : 150
ASRS Report	97452
Events
Anomaly	altitude deviation : excursion from assigned altitude altitude deviation : crossing restriction not met non adherence : published procedure
Independent Detector	other controllera other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

On localizer 30 approach to mia international descended to 3000' MSL at what I believed to be oldde fix 10.7, but was actually approximately 8 NM further out. Started descent to 1500' MSL to cross FAF at birdd at 1500' MSL. Because I was reading DME off of biscayne bay vice localizer I was lower than I should have been. Approximately 5 NM off of biscayne bay I leveled at 2100' because things didn't look right, at which time tower asked us if our altitude crossing oldde was 3000' and we believed we had crossed oldde at 3000' and replied affirmatively. As the approach continued I maintained altitude at 2100' until a visual G/south to 30 had been established and I believe the problem stems from the fact that both myself and the captain being relatively new in the advanced cockpit and working with an FMS navigation system confused the DME (localizer) readout with DME readout of the VOR. Upon closer scrutiny we determined that the actual readout of the DME was on the pfd CRT screen (lower left) and not on the RMI DME readout as it also should have been. According to our operating manual, the DME readout of the ILS/DME frequency selector should be displayed on the RMI DME display as well as on the pfd display if the EFIS panel selector switch is selected to ILS position, as it was. The VOR DME readout of biscayne bay should only have been present had the EFIS panel selector switch been selected to the VOR position. The problem posed no threat to safety of flight due to tremendous VMC conditions and visibility. Supplemental information from acn 97452: a contributory factor is the fact that both pilots are new to EFIS aircraft, and were using the old familiar DME in the RMI. The DME in the pfd was reading properly off the localizer. Callback conversation with reporter revealed the following: reporter stated they have checked pfd since and have the same indications. The DME in the RMI does stay on the tuned VOR station and does not switch to ILS. With pfd EFIS switch on ILS the readout on the pfd is the ILS DME readout and pilot admitted he knew that is what they should have been looking at. Still thinks the manual reads wrong and will bring that up to company.

Original NASA ASRS Text

Title: ACR WDB DEPARTED ALT ON APCH PRIOR TO REACHING PROPER FIX.

Narrative: ON LOC 30 APCH TO MIA INTL DSNDED TO 3000' MSL AT WHAT I BELIEVED TO BE OLDDE FIX 10.7, BUT WAS ACTUALLY APPROX 8 NM FURTHER OUT. STARTED DSCNT TO 1500' MSL TO CROSS FAF AT BIRDD AT 1500' MSL. BECAUSE I WAS READING DME OFF OF BISCAYNE BAY VICE LOC I WAS LOWER THAN I SHOULD HAVE BEEN. APPROX 5 NM OFF OF BISCAYNE BAY I LEVELED AT 2100' BECAUSE THINGS DIDN'T LOOK RIGHT, AT WHICH TIME TWR ASKED US IF OUR ALT XING OLDDE WAS 3000' AND WE BELIEVED WE HAD CROSSED OLDDE AT 3000' AND REPLIED AFFIRMATIVELY. AS THE APCH CONTINUED I MAINTAINED ALT AT 2100' UNTIL A VISUAL G/S TO 30 HAD BEEN ESTABLISHED AND I BELIEVE THE PROB STEMS FROM THE FACT THAT BOTH MYSELF AND THE CAPT BEING RELATIVELY NEW IN THE ADVANCED COCKPIT AND WORKING WITH AN FMS NAV SYS CONFUSED THE DME (LOC) READOUT WITH DME READOUT OF THE VOR. UPON CLOSER SCRUTINY WE DETERMINED THAT THE ACTUAL READOUT OF THE DME WAS ON THE PFD CRT SCREEN (LOWER LEFT) AND NOT ON THE RMI DME READOUT AS IT ALSO SHOULD HAVE BEEN. ACCORDING TO OUR OPERATING MANUAL, THE DME READOUT OF THE ILS/DME FREQ SELECTOR SHOULD BE DISPLAYED ON THE RMI DME DISPLAY AS WELL AS ON THE PFD DISPLAY IF THE EFIS PANEL SELECTOR SWITCH IS SELECTED TO ILS POS, AS IT WAS. THE VOR DME READOUT OF BISCAYNE BAY SHOULD ONLY HAVE BEEN PRESENT HAD THE EFIS PANEL SELECTOR SWITCH BEEN SELECTED TO THE VOR POS. THE PROB POSED NO THREAT TO SAFETY OF FLT DUE TO TREMENDOUS VMC CONDITIONS AND VIS. SUPPLEMENTAL INFO FROM ACN 97452: A CONTRIBUTORY FACTOR IS THE FACT THAT BOTH PLTS ARE NEW TO EFIS ACFT, AND WERE USING THE OLD FAMILIAR DME IN THE RMI. THE DME IN THE PFD WAS READING PROPERLY OFF THE LOC. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR STATED THEY HAVE CHKED PFD SINCE AND HAVE THE SAME INDICATIONS. THE DME IN THE RMI DOES STAY ON THE TUNED VOR STATION AND DOES NOT SWITCH TO ILS. WITH PFD EFIS SWITCH ON ILS THE READOUT ON THE PFD IS THE ILS DME READOUT AND PLT ADMITTED HE KNEW THAT IS WHAT THEY SHOULD HAVE BEEN LOOKING AT. STILL THINKS THE MANUAL READS WRONG AND WILL BRING THAT UP TO COMPANY.

Data retrieved from NASA's ASRS site as of August 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.