History of the Flight
On 8 March 2014, a Piper Warrior III aircraft registered PK-AEE, operated by the Indonesian Civil Aviation Institute (STPI), departed Tunggul Wulung Airport at 0151 UTC for a mutual flight exercise over Nangun area, Cilacap. On board were two student pilots; the pilot flying occupied the left seat. After takeoff, the aircraft climbed to 1,500 ft, turned left toward Nangun, and maintained 2,500 ft. After completing exercises, the aircraft returned to Tunggul Wulung. The non-flying pilot requested the controller to join the right downwind of runway 13 at 1,000 ft, then right base.
Aircraft and Personnel
The aircraft was a Piper Warrior III (serial number 2842369) with a Lycoming O-320-D3G engine and a Sensenich propeller. Total flight time since new was 305 hours 54 minutes. The aircraft was not equipped with a flight recorder. The pilot flying was 19 years old with 147 hours 14 minutes total flight time (46 hours dual, 101 hours solo). The last 100-hour inspection was performed on 19 January 2014 at 299.44 flight hours, with no findings.
Landing and Sequence
At short final, the pilot conducted the approach slightly above the glide path to avoid obstacles. The controller issued landing clearance. According to the pilot, the aircraft crossed the threshold at 70 knots. The pilot then leveled the wings and closed the throttle. After the main wheels touched the runway, while anticipating nose wheel contact, the propeller struck the ground and the nose landing gear collapsed. The aircraft came to a stop 181 meters from the initial main wheel touchdown point. Approximately 35 meters before stopping, there were several marks on the runway from the propeller and nose gear contact.
Wreckage and Impact
Examination after the occurrence showed the nose wheel had collapsed backward. Propeller blade tips were bent, and hydraulic fluid residue was observed on both sides of the nose tire fork. Scratch marks from the nose strut were present on the runway. The weather about five minutes after the event was good, with wind from 300° at 6 knots.
Analysis and Findings
The analysis discussed the landing technique and the nose landing gear failure. It concluded that the aircraft was landed using normal technique and procedure. A fatigue crack was found to have propagated from the internal surface of the nose gear sliding member. The crack could not be detected visually. The investigation suspected that the initial fatigue crack originated from a manufacturing pipe failure, and noted that such a failure would rarely occur.
The Komite Nasional Keselamatan Transportasi (KNKT) issued safety recommendations to STPI to inspect all similar nose gear sliding members for fatigue cracks and to review inspection methods for detecting non-visible cracks. The Directorate General of Civil Aviation was recommended to ensure implementation of these actions.