What was found
DURING MX TEST FLIGHT, AFTER COMPLETION OF 3600 HR INSPECTION, COMPLETED GROUND RUN AND HOVER CHECKS. PROCEEDED TO TAKEOFF, AT APPROX 100 FT AGL SLOWLY ACCELERATED ACFT THROUGH ETL, CYCLIC CONTROL LOCKED UP IN THE PITCH AXIS. NOSE OF ACFT CONTINUED TO PITCH UP, AFTER APPLICATION OF A LARGE AMOUNT OF FORCE TO THE CYCLIC, THE CONTROL BROKE FREE. RESUMED CONTROL OF THE ACFT, CIRCLED BACK TO POINT OF DEPARTURE AND LANDED. AT THE POINT THE CYCLIC BROKE FREE HAD MOMENTARY ILLUMINATION OF THE MASTER CAUTION LIGHT, AND PITCH CAUTION LIGHT.