Altitude deviation occurs when first officer's pilot responds to TCASII RA, the wrong way.

Attributes
ACN	208933
Time
Date	199204
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : lax
State Reference	CA
Altitude	msl bound lower : 30700 msl bound upper : 31000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zoa tower : jfk
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 3 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other
Route In Use	enroute : other oceanic enroute : pacific
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Route In Use	enroute : pacific enroute : other oceanic
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 17000
ASRS Report	208933
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : required legal separation non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 700
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

First officer flying aircraft with flight director system using #2 autoplt and both #1 and #1 automatic throttles. TCASII system announced 'traffic, traffic,' scope showed white diamond slightly left of our aircraft centerline. First officer concurred. His scope showed same indication and number. (South transponder equipped aircraft, level 900 ft below and left.) I looked outside at approximately scope position for visual sighting, when TCASII announced 'monitor vertical speed' twice. First officer asked 'should I do what it says?' I replied 'sure.' next thing I realized, we were descending and TCASII announced 'climb, climb, now.' I checked altitude and it read 30700 ft. Scope showed solid white diamond 700 ft below and left, when first officer started climb back to 31000 ft. Vertical speed indicator showed red dots through 6000 ft down and red dots through 1000 ft climb with 2 green dots above the 1000 ft climb. Next TCASII announced 'clear of conflict.' we were out of VHF range with mazatlan center and didn't establish high frequency contact with sfo radio until some time later. We discussed what a 'monitor vertical speed' announcement means. (No altitude deviation at that moment). Next time I shall make a more definite reply such as, hold your altitude or climb or descend as appropriate, instead of 'sure.'

Original NASA ASRS Text

Title: ALTDEV OCCURS WHEN FO'S PLT RESPONDS TO TCASII RA, THE WRONG WAY.

Narrative: FO FLYING ACFT WITH FLT DIRECTOR SYS USING #2 AUTOPLT AND BOTH #1 AND #1 AUTO THROTTLES. TCASII SYS ANNOUNCED 'TFC, TFC,' SCOPE SHOWED WHITE DIAMOND SLIGHTLY L OF OUR ACFT CTRLINE. FO CONCURRED. HIS SCOPE SHOWED SAME INDICATION AND NUMBER. (S TRANSPONDER EQUIPPED ACFT, LEVEL 900 FT BELOW AND L.) I LOOKED OUTSIDE AT APPROX SCOPE POS FOR VISUAL SIGHTING, WHEN TCASII ANNOUNCED 'MONITOR VERT SPD' TWICE. FO ASKED 'SHOULD I DO WHAT IT SAYS?' I REPLIED 'SURE.' NEXT THING I REALIZED, WE WERE DSNDING AND TCASII ANNOUNCED 'CLB, CLB, NOW.' I CHKED ALT AND IT READ 30700 FT. SCOPE SHOWED SOLID WHITE DIAMOND 700 FT BELOW AND L, WHEN FO STARTED CLB BACK TO 31000 FT. VERT SPD INDICATOR SHOWED RED DOTS THROUGH 6000 FT DOWN AND RED DOTS THROUGH 1000 FT CLB WITH 2 GREEN DOTS ABOVE THE 1000 FT CLB. NEXT TCASII ANNOUNCED 'CLR OF CONFLICT.' WE WERE OUT OF VHF RANGE WITH MAZATLAN CTR AND DIDN'T ESTABLISH HIGH FREQ CONTACT WITH SFO RADIO UNTIL SOME TIME LATER. WE DISCUSSED WHAT A 'MONITOR VERT SPD' ANNOUNCEMENT MEANS. (NO ALTDEV AT THAT MOMENT). NEXT TIME I SHALL MAKE A MORE DEFINITE REPLY SUCH AS, HOLD YOUR ALT OR CLB OR DSND AS APPROPRIATE, INSTEAD OF 'SURE.'

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.