DURING SPIN PRACTICE; THE PLT OF A C150 CAME WITHIN 600 FT OF A MIL KC135 TANKER UPON RECOVERING FROM A SPIN. THE MIL TANKER WAS OBSERVED 1000 FT AWAY AT THE SAME ALT WHEN BOTH ACFT TOOK EVASIVE ACTION.

Narrative

I WAS ACTING AS FLT INSTRUCTOR AND WORKING WITH A FLT INSTRUCTOR CANDIDATE ON THE SPIN TRAINING REQUIRED FOR THE RATING. WE WERE AT AN ALT OF APPROX 4500 FT MSL AND HAD JUST COMPLETED A 180 DEG CLRING TURN FROM N TO S. NEITHER THE STUDENT NOR MYSELF SPOTTED ANY TFC SO I DIRECTED THE STUDENT TO EXECUTE A ONE-TURN SPIN TO THE R. AS WE RECOVERED FROM THE SPIN AT AN ALT OF APPROX 3500 FT MSL WE SPOTTED A KC135 AT OUR ALT AND A RANGE OF APPROX 1000 FT. I IMMEDIATELY TOOK CTL OF THE ACFT AND EXECUTED A STEEP TURN TO THE L AWAY FROM THE TANKER. I OBSERVED THE TANKER ALSO ROLL INTO A TURN TO THE L AND CAN ONLY ASSUME THAT HE ALSO SAW US. THE ACFT MAY HAVE PASSED AS CLOSE AS 600 FT HORIZLY FROM EACH OTHER. I FEEL THAT THE PRIMARY CAUSE OF THIS INCIDENT WAS THE FAILURE OF MYSELF AND THE STUDENT TO ACQUIRE THE TANKER VISUALLY BEFORE INITIATING THE SPIN. THE ONLY EXPLANATION I CAN OFFER FOR THIS IS THAT FROM OUR PERSPECTIVE THE TANKER WOULD HAVE BEEN WELL BELOW THE HORIZON AS WE CLRED THE AREA AT 4500 FT AND THE LOW VISIBILITY PAINT SCHEME MAY HAVE MADE THE ACFT BLEND IN WITH THE GND. ADDITIONALLY; THE AIRSPACE IN WHICH THIS INCIDENT OCCURRED IS RELATIVELY BUSY AND HAS A VARIETY OF DIFFERENT TYPES OF TFC OPERATING AT DIFFERENT SPDS. IN THE FUTURE I WILL CONDUCT SPIN TRAINING FURTHER FROM WICHITA WHERE THE TFC DENSITY IS LOWER. ONE FINAL NOTE: AFTER THIS INCIDENT I CAREFULLY STUDIED THE AIRSPACE WE WERE OPERATING IN AND I MAY HAVE INADVERTENTLY BEEN OPERATING TOO CLOSE OF A FEDERAL AIRWAY (MY BEST ESTIMATE OF MY POS PUTS ME RIGHT AT THE 4 NM LIMIT). HOWEVER; I DO NOT BELIEVE THIS TO BE A FACTOR IN THIS INCIDENT BECAUSE NEITHER THE TANKER NOR MY ACFT WERE NAVING ON THE AIRWAY.