Altitude deviation altitude undershot altitude excursion during flight crew response to TCASII RA.

Attributes
ACN	217621
Time
Date	199207
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : las
State Reference	NV
Altitude	msl bound lower : 10500 msl bound upper : 10500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : las tower : pie
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	arrival other arrival star : star
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 220 flight time total : 5000 flight time type : 1700
ASRS Report	217621
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : excursion from assigned altitude altitude deviation : undershoot conflict : airborne less severe non adherence : far 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 : took evasive action other
Consequence	Other
Miss Distance	horizontal : 3000 vertical : 1000
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While descending into las on the creso 2 arrival we picked up a contact on TCASII at 12 O'clock and 10500 ft. At approximately 4 to 5 NM approach control called traffic at 12 O'clock and 4 NM. We were in a descent but started to reduce the rate of descent at this time. Shortly thereafter, a TCASII RA sounded to climb. We stopped the descent, visually acquired the traffic, an small aircraft, after the TCASII alert and started to climb to comply with the TCASII. We were in a climb when approach control called traffic at 10 O'clock. We visually acquired the 10 O'clock traffic, an other air carrier medium large transport on the radio call from approach. I started the aircraft back down and watched the small aircraft Y pass down our right side, 1000 ft below and 1/2 NM laterally. No other calls were received from approach control to indicate there was a problem with our actions.

Original NASA ASRS Text

Title: ALTDEV ALT UNDERSHOT ALT EXCURSION DURING FLC RESPONSE TO TCASII RA.

Narrative: WHILE DSNDING INTO LAS ON THE CRESO 2 ARR WE PICKED UP A CONTACT ON TCASII AT 12 O'CLOCK AND 10500 FT. AT APPROX 4 TO 5 NM APCH CTL CALLED TFC AT 12 O'CLOCK AND 4 NM. WE WERE IN A DSCNT BUT STARTED TO REDUCE THE RATE OF DSCNT AT THIS TIME. SHORTLY THEREAFTER, A TCASII RA SOUNDED TO CLB. WE STOPPED THE DSCNT, VISUALLY ACQUIRED THE TFC, AN SMA, AFTER THE TCASII ALERT AND STARTED TO CLB TO COMPLY WITH THE TCASII. WE WERE IN A CLB WHEN APCH CTL CALLED TFC AT 10 O'CLOCK. WE VISUALLY ACQUIRED THE 10 O'CLOCK TFC, AN OTHER ACR MLG ON THE RADIO CALL FROM APCH. I STARTED THE ACFT BACK DOWN AND WATCHED THE SMA Y PASS DOWN OUR R SIDE, 1000 FT BELOW AND 1/2 NM LATERALLY. NO OTHER CALLS WERE RECEIVED FROM APCH CTL TO INDICATE THERE WAS A PROBLEM WITH OUR ACTIONS.

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.