SA-5
From my fathers unpublished book written by Colonel Richard Sheffield.
 Vladivostok, September 27, 1971, SR-71, #980
IN 1971, COLONELS ROBERT (BOB) SPENCER AND RICHARD (BUTCH) SHEFFIELD FLEW ONE OF THE MOST IMPORTANT COMBAT MISSIONS OF THE COLD WAR.
BACKGROUND:
THE SOVIET UNION HAD DEVELOPED AND DEPLOYED THROUGHOUT THE USSR A RADAR AND MISSILE SYSTEM CALLED THE SA-5. IT WAS DESIGNED TO INTERCEPT AND DESTROY OVERFLYING US BOMBERS AND FIGHTERS. THE SOVIET UNION HAD GONE TO EXTREME MEASURES TO KEEP SECRET THE PARAMETERS OF THE SA-5 RADAR FREQUENCIES.
THE DEPLOYMENT OF THE SA-5 PRESENTED A CONSIDERABLE DEGRADATION TO THE U. S. BOMBER FORCES ABILITY TO SUCCESSFULLY STRIKE THE SOVIET UNION. CONSEQUENTLY, OBTAINING THE SA-5 RADAR PROFILE WAS ONE OF THE NATIONAL INTELLIGENCE COMMUNITY’S HIGHEST PRIORITIES.
THE SOVIETS WERE VERY SENSITIVE TO ANY SR-71 FLIGHT ACTIVITIES ON OR NEAR THEIR BORDERS; IT WAS DECIDED TO USE THE SR-71 TO BAIT THE SOVIETS INTO EXPOSING THEIR SA-5 SYSTEM. A SPECIAL ELINT RECORDER WAS DESIGNED BY NSA TO BE CARRIED ON THE SR-71 TO COLLECT THE SA-5 RADAR SIGNAL.
Post ~Linda Linda Sheffield Miller
THE MISSION TACTICS WERE TO SURPRISE THE SA-5 MISSILE SITE AT THE PORT CITY OF VLADIVOSTOK. THE SR-71 WOULD MAKE A DIRECT APPROACH AS THOUGH INTENDING TO OVERFLY THE SOVIET FORTIFICATION. THE MISSION WOULD BE FLOWN LATE AT NIGHT, WHEN THE LEAST EXPERIENCED PERSONNEL WOULD BE MANNING THE MISSILE SITE. THE SR-71 NIGHT TIME FLIGHT PERFORMANCE RESTRICTIONS WERE LIFTED SO THE FLIGHT COULD BE FLOWN AT MAX MACH (3.2) AND TURNS MADE AT MAX BANK OF 35 DEGREES INSTEAD OF THE NORMAL 25-DEGREES.
THE EXIGENCIES OF THE MISSION WERE: (1) TO FLY THE SR-71 FASTER AT NIGHT THAN IT HAD PREVIOUSLY BEEN FLOWN; (2) TO FLY WELL WITHIN EFFECTIVE RANGE OF THE SOVIET UNIONS MOST CAPABLE SURFACE-TO-AIR MISSILE SYSTEM WITHOUT THE SR-71 HAVING EITHER A MISSILE WARNING OR DEFENSE SYSTEM AVAILABLE; AND (3) TO USE A STEEPER BANK ANGLE THAN ANY PRIOR NIGHT FLIGHTS. BOTH THE SPEED AND BANK ANGLE HAD NEVER BEEN ATTEMPT BEFORE BY ANYONE AT NIGHT.
THE POTENTIAL RESULTS OF THE MISSION WERE SO CRUCIAL TO OUR WARTIME RETALIATORY CAPABILITY THAT THE ORDER TO EXECUTE THE FLIGHT WAS INITIATED AT THE HIGHEST LEVEL OF THE NATIONAL COMMAND AUTHORITY (THE PRESIDENT).
IT FOLLOWED THAT THE MOST SENIOR AND EXPERIENCED CREWMEMBERS WOULD BE SELECTED TO FLY THE MISSION, AND THAT WAS THE CREW OF COLONELS SPENCER AND SHEFFIELD. DURING THE MISSION BOTH THE SKILL AND EXPERIENCE OF THE CREW WERE RELIED ON HEAVILY FOR ITS SUCCESSFUL COMPLETION.

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Part 2 about the Mission to collect the SA-5 The mission resulted in the shutting down of one engine Spencer and Sheffield had to make an emergency stop in South Korea! Post ~Linda Sheffield Miller From Richard Sheffield’s unpublished book.
ON SEPTEMBER 27, 1971, ABOUT 10:30PM LOCAL TIME, COLONELS SPENCER AND SHEFFIELD LAUNCHED FROM KADENA, AIR BASE, OKINAWA, JAPAN, IN SR-71 NUMBER 980. AFTER AN AIR-TO-AIR REFUELING NORTH OF OKINAWA, THEY ACCELERATED TO MACH 3.2 AND ABOUT 80,000 FEET. THEY PROCEEDED VIA THE EAST CHINA SEA AND THE SEA OF JAPAN, TO VLADIVOSTOK AND THE TARGETED SA-5 MISSILE SITE. AS THE TARGET WAS APPROACHED, THE LEFT ENGINE OIL PRESSURE BEGAN TO DROP (AT MACH 3.2) THE SR-71 IS SUBJECT TO EXTREMELY HIGH STRUCTURAL TEMPERATURES DUE TO AIR FRICTION. WITH THESE EXCESSIVE TEMPERATURES THE LOSS OF ENGINE OIL PRESSURE CAN RESULT IN A CATASTROPHIC ENGINE FAILURE IN A VERY SHORT PERIOD OF TIME. TO PRECLUDE THIS, THE ENGINE MUST BE SHUT DOWN IMMEDIATELY).
AS THE SR-71 STARTED THE PRECISELY PROGRAMMED RIGHT TURN TO AVOID AN OVERFLIGHT, THE LEFT ENGINE OIL PRESSURE DROPPED TO ZERO. AN IMMEDIATE ENGINE SHUT DOWN WOULD CAUSE A REDUCED BANK ANGLE AND OVERFLIGHT OF VLADIVOSTOK, AND ALSO AN EXTREME DEGRADATION IN ALTITUDE. AT THE RISK OF ENGINE DISINTEGRATION AND POSSIBLE LOSS OF THE AIRCRAFT, THE PROGRAMMED ESCAPE TURN WAS CONTINUED. ONCE MISSION SUCCESS WAS ACHIEVED AND DEPARTURE FROM THE SA-5 THREAT AREA WAS ASSURED, THE LEFT ENGINE WAS SHUT DOWN AND A DESCENT TO A SINGLE ENGINE FLIGHT ALTITUDE OF ABOUT 18,000 FEET WAS BEGUN. AT THIS POINT, JAPAN AFFORDED THE NEAREST ALTERNATE BASE FOR RECOVERY, BUT WAS POLITICALLY UNACCEPTABLE.  BECAUSE OF STRONG HEADWINDS AND POOR SINGLE ENGINE FUEL PERFORMANCE, THE ONLY ACCESSIBLE FRIENDLY BASE WAS TAEGU, SOUTH KOREA.
WHEN COLONELS SPENCER AND SHEFFIELD APPROACHED TAEGU THEY HAD AN EMERGENCY FUEL SITUATION. UPON CONTACTING THE TOWER, THEY WERE INFORMED THAT THE FIELD WAS CLOSED. ONLY AFTER SOME ANIMATED CONVERSATION INFORMING THE TOWER OPERATOR THAT THERE WAS AN RF-4 ON ONE ENGINE, NEARLY OUT OF FUEL AND ABOUT TO CRASH, DID THE OPERATOR TURN ON THE RUNWAY LIGHTS SO THE SR-71 COULD LAND.
RESULTS:
WHEN THE INTELLIGENCE ANALYSTS REVIEWED THE DATA FROM THE RECORDER, THEY FOUND THAT THE SOVIETS HAD REACTED AS ANTICIPATED. THE ELECTRONIC INTELLIGENCE SIGNAL COLLECTION SYSTEM CARRIED ON COLONELS SPENCER AND SHEFFIELD’S FLIGHT BROUGHT BACK THE NECESSARY SA-5 EMISSIONS TO ENABLE OUR ELECTRONICS ENGINEERS TO DESIGN AN EFFECTIVE ELECTRONIC WARNING AND DEFENSE SYSTEM TO DELUDE THE SOVIET SA-5 MISSILE CAPABILITY.
AUTHENTICATION:
THE ACCOUNTS REFLECTED IN THE ABOVE DESCRIPTION OF THE MISSION FLOWN ON SEPTEMBER 27, 1971, ARE TRUE AND ACCURATE.
AT THE TIME OF THIS MISSION WAS FLOWN ALL SR-71 TACTICAL ACTIVITIES WERE HIGHLY CLASSIFIED. WE DID NOT WANT THE SOVIETS TO KNOW THAT WE HAD COLLECTED THE SA-5 SIGNALS. THIS MADE IT IMPOSSIBLE TO SUBMIT THE DETAILS OF THE FLIGHT IN AN AWARD RECOMMENDATION. THIS SUBJECT REMAINED CLASSIFIED UNTIL AFTER THE TIME LIMIT HAD PASSED FOR SUBMITTING THE MISSION FOR AN AWARD.
THE RECENT CHANGE IN THE AWARD REGULATIONS NOW MAKES IT POSSIBLE TO SUBMIT THIS VERY SIGNIFICANT MISSION FOR THE RECOGNITION IT DESERVES.