Center controller intervened on the descent of an air carrier light transport to question its altitu...

Attributes
ACN	273139
Time
Date	199406
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : hto
State Reference	NY
Altitude	msl bound lower : 11900 msl bound upper : 13000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air taxi
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 135
Flight Phase	descent other
Route In Use	enroute airway : v139
Person 1
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 190 flight time total : 4700 flight time type : 400
ASRS Report	263139
Person 2
Affiliation	company : air taxi
Function	flight crew : first officer
Qualification	pilot : cfi pilot : instrument pilot : commercial pilot : atp
Experience	flight time last 90 days : 150 flight time total : 3500 flight time type : 146
ASRS Report	273897
Events
Anomaly	conflict : airborne less severe other anomaly other
Independent Detector	atc equipment other atc equipment : unspecified other controllera other flight crewa
Resolutory Action	other
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

En route from phl to bdr at 13000 ft in the proximity of plume intersection on vector 139, we receive a vector of 120 degrees. Flying the 120 degree heading we were issued a descent to 11000 ft. During the descent we received another vector of 040 degrees. Passing through 12000 ft we noticed traffic passing off our immediate left, at which time ATC requested our altitude, to which I responded 11900 ft for 11000 with traffic in sight. Upon questioning ATC as to the altitude they showed us to be at, there was a pause then a response of 13000 ft, to which I explained we were given a clearance from 13000 ft to 11000 ft which is what I read back to ATC. We were then told to maintain the original request of 11000. Some confusion could have resulted from the fact that there was also a company aircraft with similar call sign on the same routing, but at a higher altitude, at the same time. Supplemental information from acn 273897: I believe the controller confused the 2 flight numbers and issued us a clearance intended for another aircraft. I base this on the controller's response to our questions, the sound of confusion in her voice and the fact that a new controller started immediately after the conflict. We are notifying our company of the similar sounding call signs on the same route.

Original NASA ASRS Text

Title: CTR CTLR INTERVENED ON THE DSCNT OF AN ACR LTT TO QUESTION ITS ALT ASSIGNMENT AND THEN SUBSEQUENTLY CONFIRMED THE SAME ALT AS ORIGINALLY GIVEN TO THE FLC.

Narrative: ENRTE FROM PHL TO BDR AT 13000 FT IN THE PROX OF PLUME INTXN ON VECTOR 139, WE RECEIVE A VECTOR OF 120 DEGS. FLYING THE 120 DEG HDG WE WERE ISSUED A DSCNT TO 11000 FT. DURING THE DSCNT WE RECEIVED ANOTHER VECTOR OF 040 DEGS. PASSING THROUGH 12000 FT WE NOTICED TFC PASSING OFF OUR IMMEDIATE L, AT WHICH TIME ATC REQUESTED OUR ALT, TO WHICH I RESPONDED 11900 FT FOR 11000 WITH TFC IN SIGHT. UPON QUESTIONING ATC AS TO THE ALT THEY SHOWED US TO BE AT, THERE WAS A PAUSE THEN A RESPONSE OF 13000 FT, TO WHICH I EXPLAINED WE WERE GIVEN A CLRNC FROM 13000 FT TO 11000 FT WHICH IS WHAT I READ BACK TO ATC. WE WERE THEN TOLD TO MAINTAIN THE ORIGINAL REQUEST OF 11000. SOME CONFUSION COULD HAVE RESULTED FROM THE FACT THAT THERE WAS ALSO A COMPANY ACFT WITH SIMILAR CALL SIGN ON THE SAME RTING, BUT AT A HIGHER ALT, AT THE SAME TIME. SUPPLEMENTAL INFO FROM ACN 273897: I BELIEVE THE CTLR CONFUSED THE 2 FLT NUMBERS AND ISSUED US A CLRNC INTENDED FOR ANOTHER ACFT. I BASE THIS ON THE CTLR'S RESPONSE TO OUR QUESTIONS, THE SOUND OF CONFUSION IN HER VOICE AND THE FACT THAT A NEW CTLR STARTED IMMEDIATELY AFTER THE CONFLICT. WE ARE NOTIFYING OUR COMPANY OF THE SIMILAR SOUNDING CALL SIGNS ON THE SAME RTE.

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.

Center controller intervened on the descent of an air carrier light transport to question its altitude assignment and then subsequently confirmed the same altitude as originally given to the flight crew.