B757 crew had altitude excursion in ZDC class a.

Attributes
ACN	474369
Time
Date	200005
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	intersection : kerno
State Reference	MD
Altitude	msl bound lower : 26000 msl bound upper : 27000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc.artcc
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	descent : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 15000 flight time type : 600
ASRS Report	474369
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : multi engine pilot : commercial
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : excursion from assigned altitude non adherence : clearance non adherence : company policies non adherence : published procedure other anomaly other
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : returned to assigned altitude
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were given clearance to cross at FL260, because the arrival chart had 'expect kerno at FL260' and 'expect somto at 13000 ft,' I had already programmed these altitudes next to these fixes on the legs page. We descended to FL260 in VNAV and upon leveling, I programmed FL260 into the cruise altitude on the cruise page. Subsequently, at kerno ATC gave us 'cross somto at 13000 ft, maintain 310 KTS or better.' I already had 13000 ft programmed on the legs page next to somto and I set 13000 ft on the MCP. Then I went to the descent page and programmed 330 KTS. As I switched to the progress page to see how far away our top of descent point was going to be, I felt the autothrottles add power to speed up (which I expected). Then I heard the first officer say 'it's climbing.' looking back at the instruments, I saw 2500 FPM up on the vsi, and 26700 ft. I disconnected the autoplt and hand flew it back down to FL260. The first officer double-checked and agreed there was no reason it should climb: cruise altitude set in FMS was FL260. Altitude in MCP was 13000 ft with 13000 ft next to somto on the legs page. Both VNAV and LNAV selected.

Original NASA ASRS Text

Title: B757 CREW HAD ALT EXCURSION IN ZDC CLASS A.

Narrative: WE WERE GIVEN CLRNC TO CROSS AT FL260, BECAUSE THE ARR CHART HAD 'EXPECT KERNO AT FL260' AND 'EXPECT SOMTO AT 13000 FT,' I HAD ALREADY PROGRAMMED THESE ALTS NEXT TO THESE FIXES ON THE LEGS PAGE. WE DSNDED TO FL260 IN VNAV AND UPON LEVELING, I PROGRAMMED FL260 INTO THE CRUISE ALT ON THE CRUISE PAGE. SUBSEQUENTLY, AT KERNO ATC GAVE US 'CROSS SOMTO AT 13000 FT, MAINTAIN 310 KTS OR BETTER.' I ALREADY HAD 13000 FT PROGRAMMED ON THE LEGS PAGE NEXT TO SOMTO AND I SET 13000 FT ON THE MCP. THEN I WENT TO THE DSCNT PAGE AND PROGRAMMED 330 KTS. AS I SWITCHED TO THE PROGRESS PAGE TO SEE HOW FAR AWAY OUR TOP OF DSCNT POINT WAS GOING TO BE, I FELT THE AUTOTHROTTLES ADD PWR TO SPD UP (WHICH I EXPECTED). THEN I HEARD THE FO SAY 'IT'S CLBING.' LOOKING BACK AT THE INSTS, I SAW 2500 FPM UP ON THE VSI, AND 26700 FT. I DISCONNECTED THE AUTOPLT AND HAND FLEW IT BACK DOWN TO FL260. THE FO DOUBLE-CHKED AND AGREED THERE WAS NO REASON IT SHOULD CLB: CRUISE ALT SET IN FMS WAS FL260. ALT IN MCP WAS 13000 FT WITH 13000 FT NEXT TO SOMTO ON THE LEGS PAGE. BOTH VNAV AND LNAV SELECTED.

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.