Altitude deviation altitude excursion created by TCASII RA command. Potential conflict sensed.

Attributes
ACN	344259
Time
Date	199608
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : buj airport : dfw
State Reference	TX
Altitude	msl bound lower : 9000 msl bound upper : 11000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dfw
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	cruise other
Route In Use	arrival other arrival star : star
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : flight engineer pilot : commercial pilot : cfi pilot : atp
Experience	flight time last 90 days : 150 flight time total : 18000 flight time type : 750
ASRS Report	344259
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : flight engineer pilot : cfi
Experience	flight time last 90 days : 200 flight time total : 6000 flight time type : 500
ASRS Report	344420
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : became reoriented flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 1000 vertical : 300
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation other

Narrative:

Over buj at 10000 ft, 250 KTS, on the blue ridge 7 STAR, first officer flying the aircraft with autoplt on. TCASII TA sounded and showed a target at 9:30-10 O'clock, 400 ft below and 3 mi out. ATC then cleared us down to 9000 ft just as TCASII gave a RA to climb at 1800-2000 FPM. The first officer, PF, started a climb and I told ATC we were beginning a TCASII climb. I then spotted a sel aircraft at our 9 O'clock, very close. Our rapid climb took us up to 11000 ft to clear the traffic and I informed ATC we were proceeding back down to 10000 ft. As ATC was telling us of traffic at 1-2 O'clock the TCASII sounded a descending RA at 1800-2000 FPM. When this last RA terminated we leveled at 10000 ft. The first aircraft was not under ATC control, the second was. Supplemental information from acn 344440: the initial conflicting aircraft was a single engine low wing at our 9 O'clock and a couple of mi approximately same altitude.

Original NASA ASRS Text

Title: ALTDEV ALT EXCURSION CREATED BY TCASII RA COMMAND. POTENTIAL CONFLICT SENSED.

Narrative: OVER BUJ AT 10000 FT, 250 KTS, ON THE BLUE RIDGE 7 STAR, FO FLYING THE ACFT WITH AUTOPLT ON. TCASII TA SOUNDED AND SHOWED A TARGET AT 9:30-10 O'CLOCK, 400 FT BELOW AND 3 MI OUT. ATC THEN CLRED US DOWN TO 9000 FT JUST AS TCASII GAVE A RA TO CLB AT 1800-2000 FPM. THE FO, PF, STARTED A CLB AND I TOLD ATC WE WERE BEGINNING A TCASII CLB. I THEN SPOTTED A SEL ACFT AT OUR 9 O'CLOCK, VERY CLOSE. OUR RAPID CLB TOOK US UP TO 11000 FT TO CLR THE TFC AND I INFORMED ATC WE WERE PROCEEDING BACK DOWN TO 10000 FT. AS ATC WAS TELLING US OF TFC AT 1-2 O'CLOCK THE TCASII SOUNDED A DSNDING RA AT 1800-2000 FPM. WHEN THIS LAST RA TERMINATED WE LEVELED AT 10000 FT. THE FIRST ACFT WAS NOT UNDER ATC CTL, THE SECOND WAS. SUPPLEMENTAL INFO FROM ACN 344440: THE INITIAL CONFLICTING ACFT WAS A SINGLE ENG LOW WING AT OUR 9 O'CLOCK AND A COUPLE OF MI APPROX SAME ALT.

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.