Fokker F100 oxygen regulators for crew and cabin attendants cylinders were overhauled with the press...

Attributes
ACN	415940
Time
Date	199810
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : zzz
State Reference	US
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Fokker 100
Operating Under FAR Part	Part 121
Flight Phase	other
Flight Plan	None
Person 1
Affiliation	company : air carrier
Function	other personnel other oversight : supervisor
Qualification	other other : other
ASRS Report	415940
Person 2
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
ASRS Report	415939
Events
Anomaly	aircraft equipment problem : less severe non adherence : published procedure non adherence : far other anomaly other
Independent Detector	other other : unspecified
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

Was in a descent to dfw on the bonham arrival. We leveled at 11000 ft and I decided to use the restroom before we got busy. I went to the restroom and came back. I was getting buckled in and putting on my head set and heard the controller call and ask if we were at 12000 ft. We were just leveling off at 12000 ft. I said yes. He said 'I told you to descend to 10000 ft.' I looked at my first officer and asked him what is going on. He told me he thought he was told to climb to 12000 ft. The controller then told us to maintain 12000 ft and nothing more was said. My first officer misunderstood and climbed when he should have descended. Unfortunately, I was not there to catch the mistake. The only factor that I can see that may have caused this (other than my being in the restroom) would have been fatigue. We were on the last day of a 3-DAY trip and had been dealing with thunderstorms and delays for 2 days and we were both tired. Unfortunately it may have caused a deviation.

Original NASA ASRS Text

Title: FOKKER F100 OXYGEN REGULATORS FOR CREW AND CABIN ATTENDANTS CYLINDERS WERE OVERHAULED WITH THE PRESSURE REGULATOR TEST UNIT CALIBRATION OVERDUE.

Narrative: WAS IN A DSCNT TO DFW ON THE BONHAM ARR. WE LEVELED AT 11000 FT AND I DECIDED TO USE THE RESTROOM BEFORE WE GOT BUSY. I WENT TO THE RESTROOM AND CAME BACK. I WAS GETTING BUCKLED IN AND PUTTING ON MY HEAD SET AND HEARD THE CTLR CALL AND ASK IF WE WERE AT 12000 FT. WE WERE JUST LEVELING OFF AT 12000 FT. I SAID YES. HE SAID 'I TOLD YOU TO DSND TO 10000 FT.' I LOOKED AT MY FO AND ASKED HIM WHAT IS GOING ON. HE TOLD ME HE THOUGHT HE WAS TOLD TO CLB TO 12000 FT. THE CTLR THEN TOLD US TO MAINTAIN 12000 FT AND NOTHING MORE WAS SAID. MY FO MISUNDERSTOOD AND CLBED WHEN HE SHOULD HAVE DSNDED. UNFORTUNATELY, I WAS NOT THERE TO CATCH THE MISTAKE. THE ONLY FACTOR THAT I CAN SEE THAT MAY HAVE CAUSED THIS (OTHER THAN MY BEING IN THE RESTROOM) WOULD HAVE BEEN FATIGUE. WE WERE ON THE LAST DAY OF A 3-DAY TRIP AND HAD BEEN DEALING WITH TSTMS AND DELAYS FOR 2 DAYS AND WE WERE BOTH TIRED. UNFORTUNATELY IT MAY HAVE CAUSED A DEV.

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.

Fokker F100 oxygen regulators for crew and cabin attendants cylinders were overhauled with the pressure regulator test unit calibration overdue.