On October 26, 2001, at 1530 mountain standard time, a Beech 58 twin-engine airplane, N8117V, was substantially damaged when the nose landing gear collapsed while landing at the Four Corners Regional Airport (FMN), Farmington, New Mexico. The airplane was registered to and operated by San Juan Pilot Training Inc., of Farmington, New Mexico, doing business as Mesa Pilot Development Center. The certified flight instructor (CFI) and commercial pilot receiving instruction were not injured. Visual meteorological conditions prevailed, and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 instructional flight. The local flight had originated from FMN at 1400. According to the flight instructor and pilot receiving instruction, they executed a low approach to runway 07 at FMN and initiated a go-around. A climb was initiated and when the gear was retracted a "loud bang or clank," was heard. The landing gear in-transit light remained illuminated and the flight proceeded to a practice area where the pilots consulted with the flight school's maintenance personnel via radio. Subsequently, the pilots performed the manual gear extension procedures, which resulted in two green lights for the main landing gear; however, the landing gear in-transit light remained illuminated and there was no green light for the nose landing gear. They pushed the annunciator test button to ensure that the cockpit nose gear light bulb was operational, and it illuminated. The flight then returned to FMN and executed a low pass near the air traffic control tower (ATCT). ATCT personnel reported that both main landing gear appeared down and locked, but the nose landing gear appeared to be partially extended. Subsequently, the airplane landed on runway 11, and when the nose gear made ground contact, it collapsed. The airplane was examined by an FAA inspector and it was discovered that the nose gear actuator retract arm (part number 104-820050-3) had fractured and was in two pieces. According to a repair facility, bulkheads in the nose structure of the airplane were structurally damaged and required replacement. The nose gear actuator retract arm was examined at the NTSB Materials Laboratory in Washington, D.C. The upper portion of the retract arm displayed two separate areas (upper left and upper right), with surface features that are consistent with fatigue. The upper fracture surface was examined with a scanning electron microscope (SEM). The fractured surface exhibited a fatigue striation pattern that emanated from multiple origins that were oriented along machining marks on its upper edge. The lower portion of the retract arm also displayed features consistent with fatigue.