Cpr mdt altitude deviation excursion from clearance altitude in reply to wrong call sign.

Attributes
ACN	82543
Time
Date	198802
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ape
State Reference	OH
Altitude	msl bound lower : 27000 msl bound upper : 27800
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zid
Operator	general aviation : corporate
Make Model Name	Medium Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : first officer oversight : pic
Qualification	pilot : instrument pilot : atp pilot : commercial
Experience	flight time last 90 days : 90 flight time total : 9500 flight time type : 3500
ASRS Report	82453
Person 2
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	altitude deviation : excursion from assigned altitude
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Aircraft departed tol exp airport on a flight to jax, fl. Departure reclred our flight to continue climbing to 8000' and maintain heading 210. Passing through 6500' departure reclred our flight to FL230. Climbing through 12500' departure switched us to cle center. Checked in with clear leaving 13500' climbing to FL230 and heading 210. Aircraft leveled at FL230 at about 5 mins after takeoff and I advised center of our level off. At this time center gave our flight a course change of direct ape and climb to FL250. We acknowledged this clearance with the normal read back and received their acknowledgement. Cle center then gave a climb clearance to FL270 and switched us to ind center. I made the normal call into ind and checked leveling at FL270. They acknowledged our flight. (Lots of traffic on frequency.) about a minute after our call in, ind called with clearance for XXX to climb to FL290. I acknowledged this clearance and received his confirmation. We started climbing to the newly assigned altitude. When approaching FL278 I heard the controller give another aircraft with similar sounding call sign (XXX ab) a climb clearance to FL290. At this time we stopped our climb and started descending back to FL270 along with conversing with center about our possible inadvertent acceptance of another aircraft's clearance. The controller said he never heard our acknowledgement or readback of the clearance. Our flight releveled at FL270 and continued on our way with no other comments by either party. South of ape VOR our flight was switched to another sector. Two mins after our relevel an airline large transport passed at 12 O'clock and 1 mi and FL280 (?). This inadvertent acceptance of another aircraft's clearance occurred because of the following: a) our flight had received 3 previous step climb clrncs. B) we were standing by and ready for another which I thought I'd heard. C) controller was handling a multitude of aircraft transgressing his sector. D) high work load for all parties involved.

Original NASA ASRS Text

Title: CPR MDT ALT DEVIATION EXCURSION FROM CLRNC ALT IN REPLY TO WRONG CALL SIGN.

Narrative: ACFT DEPARTED TOL EXP ARPT ON A FLT TO JAX, FL. DEP RECLRED OUR FLT TO CONTINUE CLBING TO 8000' AND MAINTAIN HDG 210. PASSING THROUGH 6500' DEP RECLRED OUR FLT TO FL230. CLBING THROUGH 12500' DEP SWITCHED US TO CLE CENTER. CHKED IN WITH CLR LEAVING 13500' CLBING TO FL230 AND HDG 210. ACFT LEVELED AT FL230 AT ABOUT 5 MINS AFTER TKOF AND I ADVISED CENTER OF OUR LEVEL OFF. AT THIS TIME CENTER GAVE OUR FLT A COURSE CHANGE OF DIRECT APE AND CLB TO FL250. WE ACKNOWLEDGED THIS CLRNC WITH THE NORMAL READ BACK AND RECEIVED THEIR ACKNOWLEDGEMENT. CLE CENTER THEN GAVE A CLB CLRNC TO FL270 AND SWITCHED US TO IND CENTER. I MADE THE NORMAL CALL INTO IND AND CHKED LEVELING AT FL270. THEY ACKNOWLEDGED OUR FLT. (LOTS OF TFC ON FREQ.) ABOUT A MINUTE AFTER OUR CALL IN, IND CALLED WITH CLRNC FOR XXX TO CLB TO FL290. I ACKNOWLEDGED THIS CLRNC AND RECEIVED HIS CONFIRMATION. WE STARTED CLBING TO THE NEWLY ASSIGNED ALT. WHEN APCHING FL278 I HEARD THE CTLR GIVE ANOTHER ACFT WITH SIMILAR SOUNDING CALL SIGN (XXX AB) A CLB CLRNC TO FL290. AT THIS TIME WE STOPPED OUR CLB AND STARTED DSNDING BACK TO FL270 ALONG WITH CONVERSING WITH CENTER ABOUT OUR POSSIBLE INADVERTENT ACCEPTANCE OF ANOTHER ACFT'S CLRNC. THE CTLR SAID HE NEVER HEARD OUR ACKNOWLEDGEMENT OR READBACK OF THE CLRNC. OUR FLT RELEVELED AT FL270 AND CONTINUED ON OUR WAY WITH NO OTHER COMMENTS BY EITHER PARTY. S OF APE VOR OUR FLT WAS SWITCHED TO ANOTHER SECTOR. TWO MINS AFTER OUR RELEVEL AN AIRLINE LGT PASSED AT 12 O'CLOCK AND 1 MI AND FL280 (?). THIS INADVERTENT ACCEPTANCE OF ANOTHER ACFT'S CLRNC OCCURRED BECAUSE OF THE FOLLOWING: A) OUR FLT HAD RECEIVED 3 PREVIOUS STEP CLB CLRNCS. B) WE WERE STANDING BY AND READY FOR ANOTHER WHICH I THOUGHT I'D HEARD. C) CTLR WAS HANDLING A MULTITUDE OF ACFT TRANSGRESSING HIS SECTOR. D) HIGH WORK LOAD FOR ALL PARTIES INVOLVED.

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.