Premature approach by air carrier in a night operation causes approach controller to tell crew of lo...

Attributes
ACN	262395
Time
Date	199401
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : ign airport : swf
State Reference	NY
Altitude	msl bound lower : 1600 msl bound upper : 1800
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : n90
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	cruise other descent : approach descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 80 flight time total : 4000 flight time type : 2000
ASRS Report	262395
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 7000 flight time type : 2000
ASRS Report	262386
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : published procedure non adherence : clearance
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:

Flying VOR runway 27 approach. At FAF, crossing restr is 1800 MSL idented by 11.5 DME outbound from ign VOR. First officer was flying aircraft and started his descent early at 10.5 DME and was at 1600 MSL when captain told him to correct to 1800 MSL. As we crossed the scrug fix, tower reported that ny approach showed a low altitude alert on us and we reported the FAF leaving 1800 MSL. Cause: first officer read his DME wrong and started his step down to the intermediate altitude of 1180 ft MSL early -- thus deviating 200 ft off altitude. Human factor -- DME is read outbound from the ign VOR on this approach. Since DME is usually read inbound (thus decreasing) on a VOR approach, it may have caused the confusion. Ny approach made a good, timely call on the deviation. Supplemental information from acn 262386: WX right at minimums on a non-precision approach.

Original NASA ASRS Text

Title: PREMATURE APCH BY ACR IN A NIGHT OP CAUSES APCH CTLR TO TELL CREW OF LOW ALT ALERT.

Narrative: FLYING VOR RWY 27 APCH. AT FAF, XING RESTR IS 1800 MSL IDENTED BY 11.5 DME OUTBOUND FROM IGN VOR. FO WAS FLYING ACFT AND STARTED HIS DSCNT EARLY AT 10.5 DME AND WAS AT 1600 MSL WHEN CAPT TOLD HIM TO CORRECT TO 1800 MSL. AS WE CROSSED THE SCRUG FIX, TWR REPORTED THAT NY APCH SHOWED A LOW ALT ALERT ON US AND WE RPTED THE FAF LEAVING 1800 MSL. CAUSE: FO READ HIS DME WRONG AND STARTED HIS STEP DOWN TO THE INTERMEDIATE ALT OF 1180 FT MSL EARLY -- THUS DEVIATING 200 FT OFF ALT. HUMAN FACTOR -- DME IS READ OUTBOUND FROM THE IGN VOR ON THIS APCH. SINCE DME IS USUALLY READ INBOUND (THUS DECREASING) ON A VOR APCH, IT MAY HAVE CAUSED THE CONFUSION. NY APCH MADE A GOOD, TIMELY CALL ON THE DEV. SUPPLEMENTAL INFO FROM ACN 262386: WX RIGHT AT MINIMUMS ON A NON-PRECISION APCH.

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.

Premature approach by air carrier in a night operation causes approach controller to tell crew of low altitude alert.