B727 crew had altitude excursion when they did not retract the aircraft speed brakes.

Attributes
ACN	414560
Time
Date	199809
Day	Wed
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : sto
State Reference	FO
Altitude	msl bound lower : 2300 msl bound upper : 2500
Environment
Flight Conditions	Mixed
Light	Night
Aircraft 1
Controlling Facilities	tracon : sto tracon : bgm
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent : approach descent other
Route In Use	arrival other enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 100 flight time total : 8000 flight time type : 2000
ASRS Report	414560
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	altitude deviation : overshoot non adherence : published procedure non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

First officer was flying approach. Speed brakes were in use during descent and he leveled at 2500 ft on vectors to intercept localizer runway 1. I went head down to change frequency and identify localizer and NDB as we leveled. First officer forgot to close speed brakes and I missed it. As he leveled, in a slight turn, the stick shaker activated and first officer deployed flaps to 2 degrees on his own, while calling out 'flaps 2 degrees.' the aircraft descended several hundred ft below assigned and high power was applied before the flight engineer caught the spoiler handle and called it out. The most interesting thing about this incident is that, when the first officer deployed the flaps the flap/spoiler handle warning horn went off and all 3 pilots failed to recognize it as a flap/spoiler warning but interpreted it as a cabin altitude warning (the same horn serves both functions), even though we were only 2500 ft and that warning was totally inappropriate for the situation. For 20-30 seconds, all 3 of us experienced in the airplane, misinterped the horn.

Original NASA ASRS Text

Title: B727 CREW HAD ALT EXCURSION WHEN THEY DID NOT RETRACT THE ACFT SPD BRAKES.

Narrative: FO WAS FLYING APCH. SPD BRAKES WERE IN USE DURING DSCNT AND HE LEVELED AT 2500 FT ON VECTORS TO INTERCEPT LOC RWY 1. I WENT HEAD DOWN TO CHANGE FREQ AND IDENT LOC AND NDB AS WE LEVELED. FO FORGOT TO CLOSE SPD BRAKES AND I MISSED IT. AS HE LEVELED, IN A SLIGHT TURN, THE STICK SHAKER ACTIVATED AND FO DEPLOYED FLAPS TO 2 DEGS ON HIS OWN, WHILE CALLING OUT 'FLAPS 2 DEGS.' THE ACFT DSNDED SEVERAL HUNDRED FT BELOW ASSIGNED AND HIGH PWR WAS APPLIED BEFORE THE FE CAUGHT THE SPOILER HANDLE AND CALLED IT OUT. THE MOST INTERESTING THING ABOUT THIS INCIDENT IS THAT, WHEN THE FO DEPLOYED THE FLAPS THE FLAP/SPOILER HANDLE WARNING HORN WENT OFF AND ALL 3 PLTS FAILED TO RECOGNIZE IT AS A FLAP/SPOILER WARNING BUT INTERPED IT AS A CABIN ALT WARNING (THE SAME HORN SERVES BOTH FUNCTIONS), EVEN THOUGH WE WERE ONLY 2500 FT AND THAT WARNING WAS TOTALLY INAPPROPRIATE FOR THE SIT. FOR 20-30 SECONDS, ALL 3 OF US EXPERIENCED IN THE AIRPLANE, MISINTERPED THE HORN.

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.