Read back clearance on interphone meant for another aircraft. Potential conflict result of climb thr...

Attributes
ACN	83682
Time
Date	198803
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : pxv
State Reference	IN
Altitude	msl bound lower : 29000 msl bound upper : 31000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zid
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Aircraft 2
Operator	general aviation : corporate
Make Model Name	Light 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 : 160 flight time total : 13000
ASRS Report	83682
Person 2
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : overshoot non adherence : clearance other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact other
Consequence	Other
Miss Distance	horizontal : 31800 vertical : 0
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

During climb out of cvg, F/east found it urgently necessary to leave cockpit to visit toilet. F/a's called cockpit and stated that the cabin was too hot. First officer left seat to adjust cabin temperature. While first officer was occupied at second officer panel, captain heard ATC clearance to FL350. Captain acknowledged clearance to ind center. After first officer resumed seat captain had first officer reset altitude reminder to FL350. Climbing through FL310, ind center indicated clearance limit had been FL290 and flight had passed 5.3 NM from bizjet at FL310. Problem occurred because captain had taken clearance for xyz to FL350, and acknowledged it back to center with transmitter selected to ground interphone (from gate pushback). Xyz was the call sign used on previous flight into cvg and departed just ahead of us off cvg. FL350 was the filed altitude of our flight. Suggest the practice of having aircrews departing hub cities at the same time of their previous flight call sign be evaluated for susceptibility of crews to accept wrong flight clearance. Also suggest that ATC needs to be issuing instructions via datalink with voice backup.

Original NASA ASRS Text

Title: READ BACK CLRNC ON INTERPHONE MEANT FOR ANOTHER ACFT. POTENTIAL CONFLICT RESULT OF CLIMB THROUGH FL310.

Narrative: DURING CLBOUT OF CVG, F/E FOUND IT URGENTLY NECESSARY TO LEAVE COCKPIT TO VISIT TOILET. F/A'S CALLED COCKPIT AND STATED THAT THE CABIN WAS TOO HOT. F/O LEFT SEAT TO ADJUST CABIN TEMP. WHILE F/O WAS OCCUPIED AT S/O PANEL, CAPT HEARD ATC CLRNC TO FL350. CAPT ACKNOWLEDGED CLRNC TO IND CENTER. AFTER F/O RESUMED SEAT CAPT HAD F/O RESET ALT REMINDER TO FL350. CLBING THROUGH FL310, IND CENTER INDICATED CLRNC LIMIT HAD BEEN FL290 AND FLT HAD PASSED 5.3 NM FROM BIZJET AT FL310. PROB OCCURRED BECAUSE CAPT HAD TAKEN CLRNC FOR XYZ TO FL350, AND ACKNOWLEDGED IT BACK TO CENTER WITH XMITTER SELECTED TO GND INTERPHONE (FROM GATE PUSHBACK). XYZ WAS THE CALL SIGN USED ON PREVIOUS FLT INTO CVG AND DEPARTED JUST AHEAD OF US OFF CVG. FL350 WAS THE FILED ALT OF OUR FLT. SUGGEST THE PRACTICE OF HAVING AIRCREWS DEPARTING HUB CITIES AT THE SAME TIME OF THEIR PREVIOUS FLT CALL SIGN BE EVALUATED FOR SUSCEPTIBILITY OF CREWS TO ACCEPT WRONG FLT CLRNC. ALSO SUGGEST THAT ATC NEEDS TO BE ISSUING INSTRUCTIONS VIA DATALINK WITH VOICE BACKUP.

Data retrieved from NASA's ASRS site as of August 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.

Read back clearance on interphone meant for another aircraft. Potential conflict result of climb through FL310.