A B727 flight crew was issued unknown traffic by den approach control while vectored for approach. The flight crew received a TCASII TA, then an RA. The PIC reported traffic in sight, descending immediately. The TCASII verbal announcement of 'clear of traffic' completed as the PIC leveled at 12000 ft. The so did not visually sight the traffic, but did observe the TCASII red target merge with the B727's position.

Home

Browse by month

Random

Latest

About

Contact

Attributes
ACN	391471
Time
Date	199801
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : den
State Reference	CO
Altitude	msl bound lower : 12000 msl bound upper : 13000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : den
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent : approach descent other
Route In Use	arrival other enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	general aviation : corporate
Make Model Name	Gates Learjet Corp Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	descent other
Person 1
Affiliation	company : air carrier
Function	flight crew : second officer
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 120 flight time total : 10000 flight time type : 970
ASRS Report	391471
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
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 other flight crewa
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 0 vertical : 1000
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

We had received radar vectors off the powder 2 STAR and had descended to 13000 ft. The following occurred almost simultaneously. Approach control advised of unknown type traffic thought to be military fighters because of its speed. Captain reported a 'learjet' in sight. TA warning occurred. Shortly thereafter an RA sounded 'descend, descend.' we immediately began a descent and heard, 'monitor vertical speed,' followed by 'clear of traffic.' the captain advised approach of his RA actions and asked for further clearance at 12000 ft MSL. We were cleared to maintain 12000 ft. I could not see the other aircraft from my so's station. I did see the red target merge with our position on the TCASII display.

Original NASA ASRS Text

Title: A B727 FLC WAS ISSUED UNKNOWN TFC BY DEN APCH CTL WHILE VECTORED FOR APCH. THE FLC RECEIVED A TCASII TA, THEN AN RA. THE PIC RPTED TFC IN SIGHT, DSNDING IMMEDIATELY. THE TCASII VERBAL ANNOUNCEMENT OF 'CLR OF TFC' COMPLETED AS THE PIC LEVELED AT 12000 FT. THE SO DID NOT VISUALLY SIGHT THE TFC, BUT DID OBSERVE THE TCASII RED TARGET MERGE WITH THE B727'S POS.

Narrative: WE HAD RECEIVED RADAR VECTORS OFF THE POWDER 2 STAR AND HAD DSNDED TO 13000 FT. THE FOLLOWING OCCURRED ALMOST SIMULTANEOUSLY. APCH CTL ADVISED OF UNKNOWN TYPE TFC THOUGHT TO BE MIL FIGHTERS BECAUSE OF ITS SPD. CAPT RPTED A 'LEARJET' IN SIGHT. TA WARNING OCCURRED. SHORTLY THEREAFTER AN RA SOUNDED 'DSND, DSND.' WE IMMEDIATELY BEGAN A DSCNT AND HEARD, 'MONITOR VERT SPD,' FOLLOWED BY 'CLR OF TFC.' THE CAPT ADVISED APCH OF HIS RA ACTIONS AND ASKED FOR FURTHER CLRNC AT 12000 FT MSL. WE WERE CLRED TO MAINTAIN 12000 FT. I COULD NOT SEE THE OTHER ACFT FROM MY SO'S STATION. I DID SEE THE RED TARGET MERGE WITH OUR POS ON THE TCASII DISPLAY.

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.