Medium large transport has TCASII RA due to failure to reset altimeter in class a airspace.

Attributes
ACN	257730
Time
Date	199311
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : sjn
State Reference	AZ
Altitude	msl bound lower : 28000 msl bound upper : 28000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zab
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	cruise other
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : commercial pilot : flight engineer
Experience	flight time last 90 days : 170 flight time total : 7500 flight time type : 2820
ASRS Report	257730
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance non adherence : required legal separation other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera
Resolutory Action	other
Consequence	Other
Miss Distance	horizontal : 18000 vertical : 800
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

The afternoon flight from dfw to psp was the fifth leg of the day. The crew was tired. The first officer commuted to work and started his day 13 hours earlier. I started my day 11 hours earlier. During our climb out of dfw, we were distracted and missed the altimeter change at 18000 ft. The incorrect setting caused an altitude error of approximately 180 ft. During climb and cruise I used the performance management system (pms) mode of autoplt. The pms varies the altitude slightly to help maintain airspeed. The system normally only varies the altitude approximately plus/minus 100 ft, but sometimes goes to plus/minus 140 ft. In this case, the combined deviation caused a TCASII warning with oncoming traffic. The traffic was visually in sight and passed well clear. ATC asked for altitude verification and we reported level at our altitude of FL280, our indicated altitude at the time. After checking further, I discovered the error. The distraction caused the error and I feel our physical condition, combined with the afternoon flight into the sun caused the error to go undetected. I continue to try to be as thorough as possible, and I plan to add a rechk of all checklist during the first opportunity at cruise.

Original NASA ASRS Text

Title: MLG HAS TCASII RA DUE TO FAILURE TO RESET ALTIMETER IN CLASS A AIRSPACE.

Narrative: THE AFTERNOON FLT FROM DFW TO PSP WAS THE FIFTH LEG OF THE DAY. THE CREW WAS TIRED. THE FO COMMUTED TO WORK AND STARTED HIS DAY 13 HRS EARLIER. I STARTED MY DAY 11 HRS EARLIER. DURING OUR CLB OUT OF DFW, WE WERE DISTRACTED AND MISSED THE ALTIMETER CHANGE AT 18000 FT. THE INCORRECT SETTING CAUSED AN ALT ERROR OF APPROX 180 FT. DURING CLB AND CRUISE I USED THE PERFORMANCE MGMNT SYS (PMS) MODE OF AUTOPLT. THE PMS VARIES THE ALT SLIGHTLY TO HELP MAINTAIN AIRSPD. THE SYS NORMALLY ONLY VARIES THE ALT APPROX PLUS/MINUS 100 FT, BUT SOMETIMES GOES TO PLUS/MINUS 140 FT. IN THIS CASE, THE COMBINED DEV CAUSED A TCASII WARNING WITH ONCOMING TFC. THE TFC WAS VISUALLY IN SIGHT AND PASSED WELL CLR. ATC ASKED FOR ALT VERIFICATION AND WE RPTED LEVEL AT OUR ALT OF FL280, OUR INDICATED ALT AT THE TIME. AFTER CHKING FURTHER, I DISCOVERED THE ERROR. THE DISTR CAUSED THE ERROR AND I FEEL OUR PHYSICAL CONDITION, COMBINED WITH THE AFTERNOON FLT INTO THE SUN CAUSED THE ERROR TO GO UNDETECTED. I CONTINUE TO TRY TO BE AS THOROUGH AS POSSIBLE, AND I PLAN TO ADD A RECHK OF ALL CHKLIST DURING THE FIRST OPPORTUNITY AT CRUISE.

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.