MD80 crew had TCASII RA.

Attributes
ACN	442056
Time
Date	199907
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : sea.vortac
State Reference	WA
Altitude	msl bound lower : 12100 msl bound upper : 12700
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zse.artcc
Operator	common carrier : air carrier
Make Model Name	MD-80 Super 80
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	climbout : vacating altitude
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zse.artcc
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise : level
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	442056
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : multi engine
Events
Anomaly	conflict : airborne critical non adherence : required legal separation
Independent Detector	aircraft equipment : tcas
Resolutory Action	flight crew : took evasive action
Miss Distance	horizontal : 24000 vertical : 400
Supplementary
Problem Areas	ATC Human Performance FAA
Primary Problem	FAA

Narrative:

First officer was flying the aircraft, climbing through 12100 ft MSL with clearance to 15000 ft. We were on top of clouds at about 11500 ft MSL. TCASII suddenly announced 'traffic' 1 time and then went right into 'descend, descend.' TCASII display showed traffic at about 4 mi ahead. The first officer quickly reversed his pitch and followed the command to descend at 1500-2000 FPM, which caused some concern in the cabin. The seatbelt sign was still on, but the flight attendants were just starting to move around for their service. During the RA, ZSE called us clearing us to climb to FL330. I responded that we were unable and were complying with an RA. He then said, oh, that is VFR traffic at 12500 ft eastbound. It was clear above our altitude, but the traffic was not spotted visually. When clear of traffic, we continued the climb to FL330. I wonder why we did not receive an advisory from ZSE on this aircraft if he had a transponder on, enabling the TCASII alert. We deviated about -600 ft before the clear of conflict message was played.

Original NASA ASRS Text

Title: MD80 CREW HAD TCASII RA.

Narrative: FO WAS FLYING THE ACFT, CLBING THROUGH 12100 FT MSL WITH CLRNC TO 15000 FT. WE WERE ON TOP OF CLOUDS AT ABOUT 11500 FT MSL. TCASII SUDDENLY ANNOUNCED 'TFC' 1 TIME AND THEN WENT RIGHT INTO 'DSND, DSND.' TCASII DISPLAY SHOWED TFC AT ABOUT 4 MI AHEAD. THE FO QUICKLY REVERSED HIS PITCH AND FOLLOWED THE COMMAND TO DSND AT 1500-2000 FPM, WHICH CAUSED SOME CONCERN IN THE CABIN. THE SEATBELT SIGN WAS STILL ON, BUT THE FLT ATTENDANTS WERE JUST STARTING TO MOVE AROUND FOR THEIR SVC. DURING THE RA, ZSE CALLED US CLRING US TO CLB TO FL330. I RESPONDED THAT WE WERE UNABLE AND WERE COMPLYING WITH AN RA. HE THEN SAID, OH, THAT IS VFR TFC AT 12500 FT EBOUND. IT WAS CLR ABOVE OUR ALT, BUT THE TFC WAS NOT SPOTTED VISUALLY. WHEN CLR OF TFC, WE CONTINUED THE CLB TO FL330. I WONDER WHY WE DID NOT RECEIVE AN ADVISORY FROM ZSE ON THIS ACFT IF HE HAD A XPONDER ON, ENABLING THE TCASII ALERT. WE DEVIATED ABOUT -600 FT BEFORE THE CLR OF CONFLICT MESSAGE WAS PLAYED.

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.