RPTING CAPT LOST CTL OF AN EXPERIMENTAL CESSNA 560 (C560) DURING AN EXPERIMENTAL FLT TEST RESULTING IN A 2 TURN SPIN TO THE R PRIOR TO RECOVERY. THE TEST INVOLVED AN ENG OUT PROC AT MINIMUM CTL SPDS. THE C560 WAS MODIFIED FOR A NEW DERIVATIVE OF A PROPOSED NEW MODEL WHICH HAS NOT BEEN READY FOR FAA FLT TESTING.

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MISSION WAS BRIEFED AS AN EXPERIMENTAL FLT TEST OF A NEW MODEL CITATION. TEST WAS VMCA DYNAMIC. ACFT WAS EQUIPPED WITH A SPIN CHUTE WHICH WAS TESTED AND ARMED. BUILD-UP CONDITIONS HAD BEEN PERFORMED ON PREVIOUS FLTS. THIS FLT WAS TO BE THE FINAL CHK OF THE PREVIOUSLY DETERMINED MINIMUM CTL SPDS. CONDITION WAS FLOWN PER THE PREFLT BRIEFING WITH THE R ENG BEING SHUT DOWN AT 6000 FT MSL. INITIAL ACFT RESPONSE WAS AS EXPECTED; WITH RUDDER ADEQUATELY COUNTERING THE YAW. ACFT SUDDENLY DEPARTED IN YAW AND ENTERED A R SPIN. PLT REDUCED THRUST ON THE L ENG TO IDLE AND INPUT ANTI-SPIN CTLS. ACFT RECOVERED AFTER 2 TURNS AT 3100 FT. PLT RESTARTED R ENG; CLBED TO 8000 FT; PERFORMED A FLT CTL CHK; AND MADE AN UNEVENTFUL LNDG AT ICT. VMCA TESTING IS REQUIRED BY FAR 25. IT IS HAZARDOUS TESTING AND SHOULD BE REPLACED BY AIRBORNE DATA GATHERING AT LESS CRITICAL CONDITIONS WITH SIMULATION USED FOR THE FINAL POINT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT THE INCIDENT OCCURRED DURING THE FLT TESTING PER FAR PART 25 FOR A DERIVATIVE OF THE CESSNA MODEL C560. THESE TESTS ARE NECESSARY IN ORDER TO ASSURE THAT THE ACFT WILL PASS THE FAA FLT TESTS WHEN GIVEN TO THEM FOR CERTIFICATION OF THE ACFT. SUBSEQUENT EXAMINATION OF THE REASON FOR LOSS OF CTL WAS DUE TO IMPROPER CTL INPUT BY THE FLC AND NOT THE ACFT DESIGN.