What was found
NR 1 SERVO LIGHT CAME ON. SLOWED AIRCRAFT BELOW 125 KTS. EXPERIENCED NO BINDING OF LOSS OF HYDRAULIC PRESSURE. RECYCLED SERVO JAM CIRCUIT BREAKER, LIGHT STAYED ON. LIGHT WENT OUT UPON LANDING. MAINTENANCE FOUND THE B-NUT ON THE FORWARD END OF TUBE HAD BACKED OFF AT FITTING PN AN924-4J IN THE FORWARD END OF THE TAIL BOOM ALLOWING A LOSS OF HYDRAULIC FLUID. TIGHTENED THE B-NUT AND SERVICED THE HYDRAULIC SYSTEM. RAN AIRCRAFT AND SYSTEM LEAK CHECKED GOOD.