Air carrier X descent to wrong altitude clearance interpretation TCASII TA RA with Y pilot deviation...

Attributes
ACN	261778
Time
Date	199401
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : aqn
State Reference	TX
Altitude	msl bound lower : 10600 msl bound upper : 11000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dfw tower : sps
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 240 flight time total : 11000 flight time type : 900
ASRS Report	261778
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 170 flight time total : 6700 flight time type : 5000
ASRS Report	261910
Events
Anomaly	altitude deviation : overshoot conflict : airborne less severe non adherence : clearance
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 18000 vertical : 1800
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Inbound to dallas love field on the acton arrival at 29 DME off the 040 degree radial aqn we were given a clearance to turn to a heading of 360 degrees, descend to 7000 ft and contact approach on 119.05. Shortly after beginning the descent, we received a 'TA' on the TCASII followed by an 'RA.' we climbed to resolve the RA and spotted traffic visually at our 1-2 O'clock position rapidly climbing to 10000 ft. Our lowest altitude reached during the descent was 10600 ft. We quizzed the controller about the clearance. He replied with a frequency change and descent to 7000 ft. We experienced no further difficulties. Supplemental information from acn 261910: initiated descent and immediately got a TA, then RA. Stopped descent and climbed back to 11000 ft, spotted traffic visually at about 10 O'clock, 2-3 mi. TCASII indicated traffic at 9000 ft climbing. Our lowest altitude was about 10600 ft. We asked approach (125.8, the 1 that gave us the clearance) if he gave us a descent to 7000 ft. He simply said no, but then gave us another clearance to 7000 ft. The controller was very busy and simply made a mistake. Had we been IMC and not had TCASII it could have been much more interesting.

Original NASA ASRS Text

Title: ACR X DSCNT TO WRONG ALT CLRNC INTERP TCASII TA RA WITH Y PLTDEV.

Narrative: INBOUND TO DALLAS LOVE FIELD ON THE ACTON ARR AT 29 DME OFF THE 040 DEG RADIAL AQN WE WERE GIVEN A CLRNC TO TURN TO A HDG OF 360 DEGS, DSND TO 7000 FT AND CONTACT APCH ON 119.05. SHORTLY AFTER BEGINNING THE DSCNT, WE RECEIVED A 'TA' ON THE TCASII FOLLOWED BY AN 'RA.' WE CLBED TO RESOLVE THE RA AND SPOTTED TFC VISUALLY AT OUR 1-2 O'CLOCK POS RAPIDLY CLBING TO 10000 FT. OUR LOWEST ALT REACHED DURING THE DSCNT WAS 10600 FT. WE QUIZZED THE CTLR ABOUT THE CLRNC. HE REPLIED WITH A FREQ CHANGE AND DSCNT TO 7000 FT. WE EXPERIENCED NO FURTHER DIFFICULTIES. SUPPLEMENTAL INFO FROM ACN 261910: INITIATED DSCNT AND IMMEDIATELY GOT A TA, THEN RA. STOPPED DSCNT AND CLBED BACK TO 11000 FT, SPOTTED TFC VISUALLY AT ABOUT 10 O'CLOCK, 2-3 MI. TCASII INDICATED TFC AT 9000 FT CLBING. OUR LOWEST ALT WAS ABOUT 10600 FT. WE ASKED APCH (125.8, THE 1 THAT GAVE US THE CLRNC) IF HE GAVE US A DSCNT TO 7000 FT. HE SIMPLY SAID NO, BUT THEN GAVE US ANOTHER CLRNC TO 7000 FT. THE CTLR WAS VERY BUSY AND SIMPLY MADE A MISTAKE. HAD WE BEEN IMC AND NOT HAD TCASII IT COULD HAVE BEEN MUCH MORE INTERESTING.

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.