Small aircraft X made unauthorized climb to occupied altitude. Pilot deviation.

Attributes
ACN	84858
Time
Date	198804
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : ffm
State Reference	MN
Altitude	msl bound lower : 4000 msl bound upper : 5000
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zmp
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Flight Phase	climbout : intermediate altitude cruise other
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Aircraft, High Wing, 1 Eng, Retractable Gear
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
ASRS Report	84858
Person 2
Function	flight crew : single pilot
Qualification	pilot : instrument
Events
Anomaly	altitude deviation : excursion from assigned altitude non adherence : clearance
Independent Detector	atc equipment other atc equipment : unspecified
Resolutory Action	none taken : anomaly accepted none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Aircraft X was not under radar control. There was traffic aircraft Y 1000' above him, and to the southwest. Non-radar rules in use. Pilot requested a climb. We asked him his position from a VOR to determine proximity of higher aircraft. Pilot responded that he was having a very difficult time reading us, and 'assume the climb's ok.' we took immediate action to reclear him to original altitude and issued a new frequency. About one minute later we observed his beacon target with mode C indicating 4700'. I am greatly concerned with the increasing frequency of this type of problem with general aviation pilots. We seem to be seeing it more and more, and this year's traffic levels will no doubt be at an all time high. I believe these pilot's need to be alerted of this serious safety issue now, before the heavier traffic and thunderstorms of the summer season arrives! The aircraft involved were a considerable distance away from each other with increasing separation. But without ascertaining the pilot's position before we issued a climb, we could not be assured of their proximity. The bottom line in this situation is that the pilot having a difficult time hearing the center should have stayed at previously assigned altitude or declared an emergency and advised us of nature and action he was taking. Assuming that the climb was okay was a dangerous mistake!

Original NASA ASRS Text

Title: SMALL ACFT X MADE UNAUTH CLIMB TO OCCUPIED ALT. PLT DEVIATION.

Narrative: ACFT X WAS NOT UNDER RADAR CONTROL. THERE WAS TFC ACFT Y 1000' ABOVE HIM, AND TO THE SW. NON-RADAR RULES IN USE. PLT REQUESTED A CLIMB. WE ASKED HIM HIS POSITION FROM A VOR TO DETERMINE PROX OF HIGHER ACFT. PLT RESPONDED THAT HE WAS HAVING A VERY DIFFICULT TIME READING US, AND 'ASSUME THE CLIMB'S OK.' WE TOOK IMMEDIATE ACTION TO RECLEAR HIM TO ORIGINAL ALT AND ISSUED A NEW FREQ. ABOUT ONE MINUTE LATER WE OBSERVED HIS BEACON TARGET WITH MODE C INDICATING 4700'. I AM GREATLY CONCERNED WITH THE INCREASING FREQUENCY OF THIS TYPE OF PROBLEM WITH GENERAL AVIATION PLTS. WE SEEM TO BE SEEING IT MORE AND MORE, AND THIS YEAR'S TFC LEVELS WILL NO DOUBT BE AT AN ALL TIME HIGH. I BELIEVE THESE PLT'S NEED TO BE ALERTED OF THIS SERIOUS SAFETY ISSUE NOW, BEFORE THE HEAVIER TFC AND THUNDERSTORMS OF THE SUMMER SEASON ARRIVES! THE ACFT INVOLVED WERE A CONSIDERABLE DISTANCE AWAY FROM EACH OTHER WITH INCREASING SEPARATION. BUT WITHOUT ASCERTAINING THE PLT'S POSITION BEFORE WE ISSUED A CLIMB, WE COULD NOT BE ASSURED OF THEIR PROX. THE BOTTOM LINE IN THIS SITUATION IS THAT THE PLT HAVING A DIFFICULT TIME HEARING THE CENTER SHOULD HAVE STAYED AT PREVIOUSLY ASSIGNED ALT OR DECLARED AN EMER AND ADVISED US OF NATURE AND ACTION HE WAS TAKING. ASSUMING THAT THE CLIMB WAS OKAY WAS A DANGEROUS MISTAKE!

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.