Approach control lost all radios which resulted in less than standard separation between a military aircraft and an air carrier.

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Attributes
ACN	317010
Time
Date	199509
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : slc
State Reference	UT
Altitude	msl bound lower : 20000 msl bound upper : 20000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zlc tracon : slc
Operator	other
Make Model Name	Boeing Company Undifferentiated or Other Model
Operating Under FAR Part	other : other
Flight Phase	cruise other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Route In Use	departure other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller radar : 10 flight time total : 70
ASRS Report	317010
Person 2
Affiliation	government : military
Function	flight crew : captain oversight : pic
Qualification	pilot : military
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation other anomaly other
Independent Detector	other controllera
Resolutory Action	flight crew : took evasive action none taken : unable
Consequence	Other
Miss Distance	horizontal : 13500 vertical : 400
Supplementary
Primary Problem	Navigational Facility
Air Traffic Incident	Operational Error
Situations
Navigational Aid	Unspecified

Narrative:

What caused the incident is the fact that all radios at salt lake approach failed. ZLC sector 32 worked military X into slc from the south. Sector 32 had transferred track control on military X to slc just before the radios failed. There were approximately 12-15 other aircraft in sector 32. Most were descending to ffu and had to be reassigned a new altitude to be cleared into immediate holding over ffu. 3 aircraft which received a frequency change from sector 32 to slc came back to us. Military X, who was believed at this time to be on approach's frequency continued northbound to slc at FL200. The incident happened when air carrier Y was climbing eastbound to FL230. This aircraft was on approach control frequency when the radios failed. Air carrier Y received a TCASII advisory on military X and stopped climbing till clear. This error happened because sector 32 (working military X) did not have a data block on air carrier Y and ZLC sector 3 (working air carrier Y) did not have a data block on military X. Why? Both aircraft were in approach control airspace.

Original NASA ASRS Text

Title: APCH CTL LOST ALL RADIOS WHICH RESULTED IN LTSS BTWN A MIL ACFT AND AN ACR.

Narrative: WHAT CAUSED THE INCIDENT IS THE FACT THAT ALL RADIOS AT SALT LAKE APCH FAILED. ZLC SECTOR 32 WORKED MIL X INTO SLC FROM THE S. SECTOR 32 HAD TRANSFERRED TRACK CTL ON MIL X TO SLC JUST BEFORE THE RADIOS FAILED. THERE WERE APPROX 12-15 OTHER ACFT IN SECTOR 32. MOST WERE DSNDING TO FFU AND HAD TO BE REASSIGNED A NEW ALT TO BE CLRED INTO IMMEDIATE HOLDING OVER FFU. 3 ACFT WHICH RECEIVED A FREQ CHANGE FROM SECTOR 32 TO SLC CAME BACK TO US. MIL X, WHO WAS BELIEVED AT THIS TIME TO BE ON APCH'S FREQ CONTINUED NBOUND TO SLC AT FL200. THE INCIDENT HAPPENED WHEN ACR Y WAS CLBING EBOUND TO FL230. THIS ACFT WAS ON APCH CTL FREQ WHEN THE RADIOS FAILED. ACR Y RECEIVED A TCASII ADVISORY ON MIL X AND STOPPED CLBING TILL CLR. THIS ERROR HAPPENED BECAUSE SECTOR 32 (WORKING MIL X) DID NOT HAVE A DATA BLOCK ON ACR Y AND ZLC SECTOR 3 (WORKING ACR Y) DID NOT HAVE A DATA BLOCK ON MIL X. WHY? BOTH ACFT WERE IN APCH CTL AIRSPACE.

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.