ASN Wikibase Occurrence # 307271
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information.
If you feel this information is incomplete or incorrect, you can submit corrected information.
| Date: | Saturday 24 April 2021 |
| Time: | 14:07 |
| Type: |  Piper PA-46-350P Malibu Mirage JetPROP DLX |
| Owner/operator: | private |
| Registration: | N417RK |
| MSN: | 4636249 |
| Year of manufacture: | 1999 |
| Fatalities: | Fatalities: 0 / Occupants: 2 |
| Aircraft damage: | None |
| Category: | Serious incident |
| Location: | over Noordkop Glider Field, Noord-Holland -
 Netherlands
|
| Phase: | En route |
| Nature: | Private |
| Departure airport: | Texel Airfield (EHTX) |
| Breda International Airport (EHSE) | |
| Investigating agency: | Dutch Safety Board |
| Confidence Rating: |  Accident investigation report completed and information captured |
A Schleicher ASK 21 glider, PH-1569, took off from runway 03 of the Noordkop glider airfield for a local flight using the winch launch method, at around 14.08 hours. On board were a licenced pilot, who was in control of the glider, and an instructor. The pilot stated that at an altitude of approximately 425-450 metres, PH-1569 transitioned from a climb to horizontal flight. At that stage, the winch
cable had not been released from the glider. At that moment, the pilot observed a motorised aircraft flying directly towards him. According to his estimate, the aircraft was flying approximately 25 metres lower than their glider, and the horizontal separation was around 75-100 metres. At the last moment, the motorised aircraft completed a sharp turn to the left, thereby flying past and ahead of the glider. Because of the vertical separation, the pilot saw no need to carry out an evasive manoeuvre.
According to the pilot there was no immediate risk of collision between the two aircraft, but if the motorised aircraft had not taken evasive action, it would probably have flown into the winch cable.
The motorised aircraft was N417RK, a single-engined Piper PA 46-350P Malibu. The pilot, together with
one passenger, had taken off from runway 03 at Texel International Airport at around 14.00 hours, for a VFR flight to Breda International Airport. The aircraft was flying towards Den Oever, via the Wadden Sea Corridor, at an altitude of approximately 1,750 feet. The pilot stated that he was aware of the presence of a glider airfield to the southwest of Den Oever, because he had flown this route on dozens of occasions, in the last two years.
He intended to keep to the west of a transmitter mast located on the IJsselmeer coast. Although he was aware of the location of the glider airfield, he continued to fly directly towards the glider airfield. According to the pilot, he was still flying at an altitude of 1,750 feet.
The pilot of the Piper stated that he just started preparations for initiating a descent in order to keep clear of the Schiphol 1 TMA, and was about to call Amsterdam Information via the radio, when the Airborne Collision Avoidance System (ACAS) generated a warning. When he looked up, immediately ahead of him, according to him at a distance of approximately 400-500 metres, he observed a glider. He immediately made a sharp turn to the left to avoid the glider. Following the evasive manoeuvre, he
continued his flight to Breda International Airport.
The pilot of the Piper was of the opinion that he had not caused a serious situation, because the glider was flying higher than his aeroplane and because he had performed an evasive manoeuvre, on time. Moreover, he believed he was flying high enough to be able to overfly the glider airfield safely, and according to him flying at this location was not prohibited. He had not observed the winch cable and was not aware of the fact that the Aeronautical Information Publication states that gliders can be winch launched to an altitude of 1,800 feet AAL from the Noordkop glider airfield.
Radar data show that N417RK was flying above the Wadden Sea at an altitude of approximately 1,750 feet. Before reaching the coast, the pilot altered the heading of the aeroplane slightly to the south, and upon reaching the coast of Noord-Holland, the aeroplane descended to approximately 1,400 feet. The aeroplane then flew over the northern perimeter of the glider airfield, and made the evasive manoeuvre above the glider airfield. At the moment of the evasive manoeuvre, N417RK was flying at
an altitude of approximately 1,400 feet. According to the FLARM data, at that moment, PH-1569 was flying west of N417RK, at an altitude of approximately 1,690 feet (QNH). The horizontal separation between the two aircraft was approx. 180 metres and the vertical separation approx. 290 feet (88 metres).
The Noordkop glider airfield was made operational in 2018, after having moved from another location. The pilot of the N417RK was aware of the presence of the glider airfield because he regularly flew to and from Texel Airport. The investigation failed to explain why the pilot opted to change his heading in such a way that it meant he would fly over the glider airfield. There is sufficient space between the glider airfield and the transmitter mast on the coast or to the east of the transmitter mast to pass the glider airfield at a safe distance. The change of heading and the descent increased the risk of a hazardous
situation.
Sources:
https://www.onderzoeksraad.nl/en/page/19287/airprox-alexander-schleicher-ask-21-ph-1569-piper-pa-46-350p-n417rk
https://magazines.openbaarministerie.nl/opportuun/2022/06/luchtvaartzaken
Revision history:
| Date/time | Contributor | Updates |
|---|---|---|
| 29-Sep-2023 08:33 | Ron Averes | Updated |
Corrections or additions? ... Edit this accident description
The Aviation Safety Network is an exclusive service provided by:
Quick Links:
| ASN Home | Send Correction / Feedback |
| FSF Home | Disclaimer | Copyright |
| Contact Us | Privacy Policy |
| Press / Media |
CONNECT WITH US:
©2024 Flight Safety Foundation