ZDV controller concerned with intrafac frequency release and maintenance coordination failure.

Attributes
ACN	503642
Time
Date	200103
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : tbe.vortac
State Reference	CO
Altitude	msl single value : 31000
Environment
Weather Elements	Turbulence
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdv.artcc
Operator	other
Make Model Name	Learjet 24
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar pilot : private
Experience	controller radar : 13 flight time total : 50
ASRS Report	503642
Person 2
Affiliation	government : faa
Function	controller : supervisor
Qualification	controller : radar
Events
Anomaly	other anomaly other
Independent Detector	other controllera other other : 3
Resolutory Action	none taken : detected after the fact
Consequence	faa : investigated
Supplementary
Problem Areas	ATC Human Performance Maintenance Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Intra Facility Coordination Failure
Situations
ATC Facility	communication equipment : zdv.artcc procedure or policy : zdv.artcc

Narrative:

While working sector 29, a high altitude sector in ZDV, the controller in charge deselected my main transmitter and selected my standby radios. I was busy at the time and was not informed why the change was made. I got the impression it was necessary for maintenance. I needed to change the altitude of a particular aircraft (a military learjet). I repeatedly called this aircraft without receiving a response. I incorrectly assumed the aircraft had a radio problem. Multiple calls to ZAB had to be made since the military aircraft was approaching their airspace. Planes had to be turned out of the way. The technicians had told me to switch to my standby radios and then they effectively turned them off. In other words, they turned off the wrong radios. I didn't know my radios weren't working or if I could switch back to my main radio or if it would even work. After 2 or 3 mins, I figured it out and switched to a third back-up radio that worked. The heavy workload at the time was a factor. I understand that at times a technician can make a mistake, but if there had been better coordination with me or a delay in their activities till the sector cooled off, the event wouldn't have gotten so chaotic.

Original NASA ASRS Text

Title: ZDV CTLR CONCERNED WITH INTRAFAC FREQ RELEASE AND MAINT COORD FAILURE.

Narrative: WHILE WORKING SECTOR 29, A HIGH ALT SECTOR IN ZDV, THE CIC DESELECTED MY MAIN XMITTER AND SELECTED MY STANDBY RADIOS. I WAS BUSY AT THE TIME AND WAS NOT INFORMED WHY THE CHANGE WAS MADE. I GOT THE IMPRESSION IT WAS NECESSARY FOR MAINT. I NEEDED TO CHANGE THE ALT OF A PARTICULAR ACFT (A MIL LEARJET). I REPEATEDLY CALLED THIS ACFT WITHOUT RECEIVING A RESPONSE. I INCORRECTLY ASSUMED THE ACFT HAD A RADIO PROB. MULTIPLE CALLS TO ZAB HAD TO BE MADE SINCE THE MIL ACFT WAS APCHING THEIR AIRSPACE. PLANES HAD TO BE TURNED OUT OF THE WAY. THE TECHNICIANS HAD TOLD ME TO SWITCH TO MY STANDBY RADIOS AND THEN THEY EFFECTIVELY TURNED THEM OFF. IN OTHER WORDS, THEY TURNED OFF THE WRONG RADIOS. I DIDN'T KNOW MY RADIOS WEREN'T WORKING OR IF I COULD SWITCH BACK TO MY MAIN RADIO OR IF IT WOULD EVEN WORK. AFTER 2 OR 3 MINS, I FIGURED IT OUT AND SWITCHED TO A THIRD BACK-UP RADIO THAT WORKED. THE HVY WORKLOAD AT THE TIME WAS A FACTOR. I UNDERSTAND THAT AT TIMES A TECHNICIAN CAN MAKE A MISTAKE, BUT IF THERE HAD BEEN BETTER COORD WITH ME OR A DELAY IN THEIR ACTIVITIES TILL THE SECTOR COOLED OFF, THE EVENT WOULDN'T HAVE GOTTEN SO CHAOTIC.

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.