B737-300 flight crew misses crossing restr.

Attributes
ACN	333610
Time
Date	199604
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : swl
State Reference	MD
Altitude	msl bound lower : 15000 msl bound upper : 15500
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	artcc : zdc
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	descent other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : cfi pilot : flight engineer pilot : instrument pilot : commercial
Experience	flight time last 90 days : 225 flight time total : 14000 flight time type : 9000
ASRS Report	333610
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : crossing restriction not met altitude deviation : undershoot non adherence : clearance
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : became reoriented
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

ATC originally gave a crossing restr of radds (swl/30 NM) at 15000 ft. Before top of descent, controller gave off course vector for traffic. When clear of traffic clearance was back direct swl to cross 30 NM at 15000 ft. Captain inadvertently programmed FMC to cross 15 NM swl at 15000 ft. (Copilot was off ATC getting ATIS). When copilot returned to frequency, captain repeated crossing restr to copilot as 15 NM swl at 15000 ft. ATC noticed we should have started descent and queried crew. Descent immediately started and level off occurred at 27 NM swl. No traffic conflict. Even with all the check and balances of altitude readbacks with other crew members, system aren't yet in place to correct this type of error, when other crew member is off air (in this case with ATIS). Perhaps as a safety feature clearance should be hard copied, instead of entered into FMC from memory. Then, clearance can be repeated from hard copy to other crew member when they return to center/ATC frequency.

Original NASA ASRS Text

Title: B737-300 FLC MISSES XING RESTR.

Narrative: ATC ORIGINALLY GAVE A XING RESTR OF RADDS (SWL/30 NM) AT 15000 FT. BEFORE TOP OF DSCNT, CTLR GAVE OFF COURSE VECTOR FOR TFC. WHEN CLR OF TFC CLRNC WAS BACK DIRECT SWL TO CROSS 30 NM AT 15000 FT. CAPT INADVERTENTLY PROGRAMMED FMC TO CROSS 15 NM SWL AT 15000 FT. (COPLT WAS OFF ATC GETTING ATIS). WHEN COPLT RETURNED TO FREQ, CAPT REPEATED XING RESTR TO COPLT AS 15 NM SWL AT 15000 FT. ATC NOTICED WE SHOULD HAVE STARTED DSCNT AND QUERIED CREW. DSCNT IMMEDIATELY STARTED AND LEVEL OFF OCCURRED AT 27 NM SWL. NO TFC CONFLICT. EVEN WITH ALL THE CHK AND BALS OF ALT READBACKS WITH OTHER CREW MEMBERS, SYS AREN'T YET IN PLACE TO CORRECT THIS TYPE OF ERROR, WHEN OTHER CREW MEMBER IS OFF AIR (IN THIS CASE WITH ATIS). PERHAPS AS A SAFETY FEATURE CLRNC SHOULD BE HARD COPIED, INSTEAD OF ENTERED INTO FMC FROM MEMORY. THEN, CLRNC CAN BE REPEATED FROM HARD COPY TO OTHER CREW MEMBER WHEN THEY RETURN TO CTR/ATC FREQ.

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.