Winch cables can kill
Almost all gliding sites in the UK use a winch launch, where gliders are launched with a winch and steel cable instead of being towed by an aircraft. 78 out of 87 (90%) winch launch to at least 2,000 feet above ground level.
A winch launching glider can reach over 1,000 feet in about 20 seconds. Once the cable is released it descends under a small parachute, which takes another 20 to 30 seconds, and is effectively invisible.
As well as launching gliders pilots should plan for gliders being towed, or in free flight around the site, and tug aircraft returning to the circuit.
Powered aircraft and helicopter pilots
To avoid an incident or accident pilots should consider the location of glider sites and the altitude to which they operate when they are planning a flight.
Gliding sites are marked differently on paper VFR charts and VFR moving maps. On a paper VFR chart the site will be depicted with a blue circle and a G, with figure in thousands of feet above mean sea level (amsl) to which the cable may extend and be released. A VFR moving map may use a glider symbol to identify the site, but the maximum cable altitude may not be visible without actions to reveal more details.
Details of the sites are published in the UK AIP at ENR 5.5 (Aerial Sporting and Recreational Activities). This includes winch heights above ground level, site elevations above mean sea level and operator contacts.
The gliding site altitude only relates to the maximum operating altitude of the winch launch cable. Pilots should expect gliders in free-flight above the annotated altitude and around the site.
The UK Airprox Board advise pilots of powered aircraft and helicopters to avoid glider sites at all times; and to only ever overfly them if they have timely, positive confirmation from the site itself that they are not active.
Recording and reporting incidents
If the overflying aircraft caused danger and the safety of an aircraft may have been compromised an Airprox should be reported to the UK Airprox Board (UKAB). Formally a pilot should report an Airprox, but in the case of an overflight UKAB may accept reports from responsible ground observers, such as an instructor or duty pilot.
- Airspace & Safety Initiative occurrence (08): Infringement and overflight of active winch-launch glider sites
- British Gliding Association (BGA): Overflight of winch launch site guidance
- BGA winch cable warning e-poster to download and display