On July 23, 2015, about 1605 eastern daylight time, a Piper PA-28R-180, N4631J, experienced a runway excursion while landing with an unsafe nose landing gear indication at the Fort Lauderdale Executive Airport (FXE), Fort Lauderdale, Florida. The flight instructor and pilot-rated student were not injured. The airplane was substantially damaged. The airplane was owned by FlyDreams Aircraft Corporation, and operated by SkyEagle Aviation Academy, under the provisions of 14 Code of Federal Regulations (CFR) Part 91, as a local, instructional flight. Visual meteorological conditions prevailed at the time and no flight plan was filed. The flight originated from FXE about 1330. The flight instructor stated that after completing the last maneuver as part of the "Pre-Landing checks" he noticed the landing gear transition light was on. He then lowered the landing gear and did not get a down and locked indication from the nose landing gear. He performing the emergency gear extension but still did not get a down and locked indication. He established contact with the flight school, and then proceeded to FXE where he performed a low pass. He departed the area and performed emergency extension of the landing gear which resulted in down and locked indication from all landing gears, but noticed a left yaw. He also reported the left rudder pedal was fully forward, which required an abnormal amount of right rudder input. He performed another low pass at FXE and was informed by company personnel that the nose landing gear appeared to be deflected to the left. He returned to FXE where he performed a soft field landing. He secured the engine after touchdown, and when the nose landing gear contacted the runway, the airplane veered to the left and came to rest upright on taxiway G. Post-accident examination of the airplane showed the engine and nose gear strut mount assembly, part number 67119-049, was fractured several inches on each side of the aircraft centerline in the area of the nose landing gear pivot location. The fractured section was retained for further examination by the National Transportation Safety Board (NTSB) Materials Laboratory. According to the NTSB Materials Laboratory Factual Report, both fracture surfaces exhibited fatigue cracks that emanated from multiple origins on the outer surface that propagated through the wall of the tube portion. A copy of the NTSB Materials Laboratory Factual Report is contained in the NTSB public docket. The airplane was purchased by the operator on June 30, 2015. Before purchase, an overhauled engine was installed and an annual inspection was signed off as being completed. The airplane total time at the annual inspection was 8,524.4 hours. Since the annual inspection had been performed, the airplane had been operated for about 15 hours. The airplane was manufactured in 1968, and according to the operator, the only maintenance records that were available were from August 1994, to present. Of the available maintenance records, there was no record that the engine and nose gear strut mount assembly being replaced. No determination could be made as to the time on the engine and nose gear strut mount assembly.