Altitude deviation altitude excursion.

Attributes
ACN	223955
Time
Date	199210
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : dfw
State Reference	TX
Altitude	msl bound lower : 10700 msl bound upper : 11000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dfw
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : commercial pilot : atp
Experience	flight time last 90 days : 60 flight time total : 5600
ASRS Report	223955
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance other anomaly other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : regained aircraft control
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 800
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

In an medium large transport series aircraft, I reached arina intersection at 11000 ft MSL and 210 KIAS. ATC had instructed me to depart arina heading 130 degrees to transition to the dfw east complex. At arina I engaged heading select and the aircraft began the turn to 130 degrees. With no further input, the aircraft initiated a rapid descent. I disengaged the autoplt and began to climb. The total altitude deviation was 300 ft. TCASII RA mode was triggered and commanded a climb because of another aircraft climbing rapidly to 10000 ft. We both had the traffic in sight and we missed it by 1000 ft and 1/2 mi. During the entire evolution the altitude select window was set at 11000 ft and no VNAV or dfgc inputs were made.

Original NASA ASRS Text

Title: ALTDEV ALT EXCURSION.

Narrative: IN AN MLG SERIES ACFT, I REACHED ARINA INTXN AT 11000 FT MSL AND 210 KIAS. ATC HAD INSTRUCTED ME TO DEPART ARINA HDG 130 DEGS TO TRANSITION TO THE DFW E COMPLEX. AT ARINA I ENGAGED HDG SELECT AND THE ACFT BEGAN THE TURN TO 130 DEGS. WITH NO FURTHER INPUT, THE ACFT INITIATED A RAPID DSCNT. I DISENGAGED THE AUTOPLT AND BEGAN TO CLB. THE TOTAL ALTDEV WAS 300 FT. TCASII RA MODE WAS TRIGGERED AND COMMANDED A CLB BECAUSE OF ANOTHER ACFT CLBING RAPIDLY TO 10000 FT. WE BOTH HAD THE TFC IN SIGHT AND WE MISSED IT BY 1000 FT AND 1/2 MI. DURING THE ENTIRE EVOLUTION THE ALT SELECT WINDOW WAS SET AT 11000 FT AND NO VNAV OR DFGC INPUTS WERE MADE.

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.