Small transport X had less than standard separation from aircraft Y. Pilot deviation.

Attributes
ACN	139355
Time
Date	199003
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : pie
State Reference	FL
Altitude	msl bound lower : 31000 msl bound upper : 32200
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zjx
Operator	general aviation : personal
Make Model Name	Small Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other
Flight Phase	climbout : intermediate altitude cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : private
Experience	flight time last 90 days : 20 flight time total : 3718 flight time type : 20
ASRS Report	139355
Person 2
Function	flight crew : single pilot
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : required legal separation non adherence : clearance
Independent Detector	atc equipment other atc equipment : unspecified other controllera
Resolutory Action	controller : issued new clearance other
Consequence	faa : investigated faa : reviewed incident with flight crew
Miss Distance	horizontal : 24000 vertical : 700
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Small transport X srq with a clearance to climb to 3000', expect FL410 in 10 mins. During climb I was cleared, in steps, to FL330. Clearance was amended before I reached FL290 to hold at FL290. Clearance was again amended to FL310 as I was climbing to FL290. As I reached FL310, or shortly after I heard, 'small transport X cleared to FL330.' since I had previously been cleared to FL330, I acknowledged, 'small transport X cleared to 330,' and started to climb. At about XX35 am EST, as I passed 32200', I was asked to go back to FL310 due to aircraft Y at FL330. Since it is not unusual for controllers to accept acknowledgement west/O reconfirmation, I had no idea controller may not have heard me when I acknowledged, 'small transport X 330.' perhaps controllers should carefully roger receipt of each transmission. Callback conversation with reporter revealed the following: the reporter stated he has an INS rating which is current and that another non-pilot was in the aircraft. The reporter called the ZJX after landing and was told he had deviated from assigned altitude and had a conflict with another aircraft, 4 mi horizontal and 700' vertical.

Original NASA ASRS Text

Title: SMT X HAD LESS THAN STANDARD SEPARATION FROM ACFT Y. PLT DEVIATION.

Narrative: SMT X SRQ WITH A CLRNC TO CLB TO 3000', EXPECT FL410 IN 10 MINS. DURING CLB I WAS CLRED, IN STEPS, TO FL330. CLRNC WAS AMENDED BEFORE I REACHED FL290 TO HOLD AT FL290. CLRNC WAS AGAIN AMENDED TO FL310 AS I WAS CLBING TO FL290. AS I REACHED FL310, OR SHORTLY AFTER I HEARD, 'SMT X CLRED TO FL330.' SINCE I HAD PREVIOUSLY BEEN CLRED TO FL330, I ACKNOWLEDGED, 'SMT X CLRED TO 330,' AND STARTED TO CLB. AT ABOUT XX35 AM EST, AS I PASSED 32200', I WAS ASKED TO GO BACK TO FL310 DUE TO ACFT Y AT FL330. SINCE IT IS NOT UNUSUAL FOR CTLRS TO ACCEPT ACKNOWLEDGEMENT W/O RECONFIRMATION, I HAD NO IDEA CTLR MAY NOT HAVE HEARD ME WHEN I ACKNOWLEDGED, 'SMT X 330.' PERHAPS CTLRS SHOULD CAREFULLY ROGER RECEIPT OF EACH XMISSION. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: THE RPTR STATED HE HAS AN INS RATING WHICH IS CURRENT AND THAT ANOTHER NON-PLT WAS IN THE ACFT. THE RPTR CALLED THE ZJX AFTER LNDG AND WAS TOLD HE HAD DEVIATED FROM ASSIGNED ALT AND HAD A CONFLICT WITH ANOTHER ACFT, 4 MI HORIZ AND 700' VERT.

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.