Maintenance technician working on standby equipment block primary frequencys.

Attributes
ACN	250493
Time
Date	199309
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : dal
State Reference	TX
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : dal
Person 1
Affiliation	government : faa
Function	controller : clearance delivery
Qualification	controller : non radar
ASRS Report	250493
Person 2
Affiliation	government : faa
Function	controller : ground
Qualification	controller : radar
Experience	controller military : 4 controller non radar : 4 controller radar : 7
ASRS Report	250597
Events
Anomaly	other anomaly other
Independent Detector	other controllera
Resolutory Action	other
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

I was training a controller on clearance delivery when a stuck microphone indication overrode my frequency to the point that I could not transmit or receive. I delegated the position to ground control who had 1 frequency to work with. We found out later, maintenance was working on our standby frequencys and it was interfering with our main frequencys. A maintenance technician was asked to report to the tower cabin attendant to see what was going on. The technician then called out to his co-worker to ensure he was not testing on the main frequencys. He was and the frequencys returned to normal after he stopped his testing. Supplemental information from acn 250597: the controllers working FD/clearance delivery and radar lost their position also. Clearance delivery functions combined with my ground control duties on frequency 123.7. The ground control frequency was once again jammed with what appeared to be another stuck microphone. Ground control functions were retransfered to frequency 123.7. 'Open microphone' continued on 121.75. During this entire time, tower (local control) and clearance delivery xmissions came out over the speaker. Technicians were instructed to stop their work on the field transmitters (backups). They had apparently caused the keyed up situation.

Original NASA ASRS Text

Title: MAINT TECHNICIAN WORKING ON STANDBY EQUIP BLOCK PRIMARY FREQS.

Narrative: I WAS TRAINING A CTLR ON CLRNC DELIVERY WHEN A STUCK MIKE INDICATION OVERRODE MY FREQ TO THE POINT THAT I COULD NOT XMIT OR RECEIVE. I DELEGATED THE POS TO GND CTL WHO HAD 1 FREQ TO WORK WITH. WE FOUND OUT LATER, MAINT WAS WORKING ON OUR STANDBY FREQS AND IT WAS INTERFERING WITH OUR MAIN FREQS. A MAINT TECHNICIAN WAS ASKED TO RPT TO THE TWR CAB TO SEE WHAT WAS GOING ON. THE TECHNICIAN THEN CALLED OUT TO HIS CO-WORKER TO ENSURE HE WAS NOT TESTING ON THE MAIN FREQS. HE WAS AND THE FREQS RETURNED TO NORMAL AFTER HE STOPPED HIS TESTING. SUPPLEMENTAL INFO FROM ACN 250597: THE CTLRS WORKING FD/CD AND RADAR LOST THEIR POS ALSO. CLRNC DELIVERY FUNCTIONS COMBINED WITH MY GND CTL DUTIES ON FREQ 123.7. THE GND CTL FREQ WAS ONCE AGAIN JAMMED WITH WHAT APPEARED TO BE ANOTHER STUCK MIKE. GND CTL FUNCTIONS WERE RETRANSFERED TO FREQ 123.7. 'OPEN MIKE' CONTINUED ON 121.75. DURING THIS ENTIRE TIME, TWR (LCL CTL) AND CLRNC DELIVERY XMISSIONS CAME OUT OVER THE SPEAKER. TECHNICIANS WERE INSTRUCTED TO STOP THEIR WORK ON THE FIELD XMITTERS (BACKUPS). THEY HAD APPARENTLY CAUSED THE KEYED UP SIT.

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.