Date: 201704
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Skyhawk 172/Cutlass 172
Operator: FBO
Operating under: Part 91
Flight plan: None
Mission: Training
Flight phase: Landing
ATC / advisory: Tower ZZZ
Aircraft component: Nose Gear Wheel
Component problem: Failed
Reporter organization: FBO
Reporter function: Instructor; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Flight Instructor
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Ground Strike - Aircraft; Ground Event / Encounter Loss Of Aircraft Control
Detector: Person Flight Crew
When detected: In-flight
Result: Aircraft Aircraft Damaged; General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: I conducted a student training flight with a Part 61 Private Pilot student. This student is at the end of his training and preparing to conduct his PPL check-ride. He is a currently rated Sport Pilot with a valid FAA medical. We began our brief that morning for a local area flight. We reviewed the 'PAVE' checklist (pilot; aircraft; environment; and external pressures). Both the student and I were feeling well and agreed to pre-flight the aircraft at the end of our brief. The weather was observed as 10 SM visibility with clear skies; and was forecasted to remain so throughout the day. There was an AIRMET Tango across the forecast area but the surface winds were only 5-7 knots in our vicinity. There were no NOTAMs or TFRs of significance to our flight based on the airports that were part of our plan.We completed our conduct-of-flight brief for the order of maneuvers that we would fly and then I sent the student out to begin the pre-flight of the aircraft. The student has well over 100 total flight hours and has conducted numerous supervised and unsupervised pre-flights on this model aircraft so I felt confident in his knowledge and ability to initiate a pre-flight inspection. My office window views the flight school flight line and our aircraft was parked directly in front of that window. I observed the student using the checklist to pre-flight our aircraft and when I joined him; he informed me that he needed assistance checking the oil level as the oil-filler tube was screwed too tight. I assisted him with that and completed my walk-around to ensure that we had two sets of eyes on the aircraft. I inspected the nose gear assembly and strut extension during my inspection; as per the checklist; but noted nothing unusual about the nose tire or its hardware.The student used the checklist to conduct the start-up; taxi; and run-up. He and I noted nothing unusual during that process with regard to nose wheel steering during taxi. We then conducted an uneventful short-field take-off; departing to our working area. At the completion of the maneuvers in the area; we checked the ATIS at ZZZ and contacted ZZZ Tower. We requested multiple touch-and-go landings and were directed to make a downwind entry for runway XXR. The first two (2) touch-and-go landings were well executed by the student with a stabilized rate of descent and smooth touchdown. No abnormal behavior of the nosewheel was noted during the landings or roll-outs. On the third touch-and-go; the student landed slightly right of centerline but smoothly. The aircraft initially tracked straight ahead. He retracted the flaps and was about to add power for the 'go' when the aircraft began a left drift. I called for the student to release the brakes and he stated that he was not on them. I was 'riding' the rudder pedals and knew that they were neutral. With the winds essentially straight down the runway and no obvious explanation for the drift; I told the student to keep the throttle back as my intent was now to stop the aircraft on the runway and diagnose the problem on the ground. At that same moment; I heard a heard a slight grinding noise and initially suspected that the left main tire had either gone flat or that the brake caliper had seized; which would explain the left drift in my mind. The aircraft continued to decelerate normally but the grinding noise intensified as I perceived the nose cowling settling more than usual. I immediately pulled the mixture to idle cut-off to secure the engine; applied firm braking; and saw a tire shoot forward on the left side of the aircraft. The sequence from grinding noise to shut-down occurred within about 10 seconds. There was never a nose-wheel 'shimmy' or any unusual feedback through the rudder pedals during this process or during any portion of the flight. I informed tower of our landing gear situation on the runway and that we had shut-down. I also stated that we would need a tug to clear the runway.As ZZZ Crash Fire Rescue and Airport Ops vehicles were arriving; I exited the aircraft to inspect for damage. ZZZ Airfield Ops personnel had me complete their event paperwork and the aircraft was released by a representative of the NTSB via the phone. The aircraft was then cleared off the runway and I returned by vehicle to our departure airport to complete notification to the FAA of this incident.

Callback: Instructor pilot reported post maintenance inspection of a sister aircraft revealed the wrong nut was used to secure the nose wheel assembly.



Synopsis: C172 instructor pilot reported the nose wheel separated from the aircraft on landing. Post maintenance inspection of a sister aircraft revealed the wrong nut was used on the nose gear assembly.