Potential conflict develops as the old clearance readback and hearback problem rears its ugly head a...

Attributes
ACN	143793
Time
Date	199004
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : eno
State Reference	DE
Altitude	msl bound lower : 26200 msl bound upper : 27000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc tower : ftw
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other descent other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 7800 flight time type : 3800
ASRS Report	143793
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : required legal separation other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 4500 vertical : 200
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	Operational Error Pilot Deviation other
Situations
ATC Facility	other physical facility procedure or policy : unspecified

Narrative:

ZDC cleared us to descend to FL260. As we were leveling (approximately 26200') an medium large transport appeared at approximately same altitude, opposite direction, 1/2-1 mi to our right. When I asked controller about traffic he said it was at FL260 but we were cleared only to FL270. I told him he had cleared us to FL260 and that we read back FL260. No evasive action was taken.

Original NASA ASRS Text

Title: POTENTIAL CONFLICT DEVELOPS AS THE OLD CLRNC READBACK AND HEARBACK PROBLEM REARS ITS UGLY HEAD AGAIN.

Narrative: ZDC CLRED US TO DSND TO FL260. AS WE WERE LEVELING (APPROX 26200') AN MLG APPEARED AT APPROX SAME ALT, OPPOSITE DIRECTION, 1/2-1 MI TO OUR RIGHT. WHEN I ASKED CTLR ABOUT TFC HE SAID IT WAS AT FL260 BUT WE WERE CLRED ONLY TO FL270. I TOLD HIM HE HAD CLRED US TO FL260 AND THAT WE READ BACK FL260. NO EVASIVE ACTION WAS TAKEN.

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.

Potential conflict develops as the old clearance readback and hearback problem rears its ugly head again.