|This article does not cite any references or sources. (September 2007)|
Helicopter banners are made from highly durable light weight polyester. These are manufactured from designs taken from vector graphics; however, standard jpeg images may also be used. A helicopter banner can range in size from 5,000 sq ft (500 m2) up to 45,000 sq ft (4,200 m2). Appearance in flight is affected by size; larger banners have difficulty retaining their desired square shape, affecting how readable the banner is. Designing a curve shape into the front of the banner stabilises it into the correct shape in flight. The optimum size for such banners is 1,500 m² or approx 15,000 ft².
The system features a “long line” (a rope similar to that used for rock climbing) attached to the helicopter with a deadweight attached to the other. The helicopter banner itself is positioned approximately 46 m (150 ft) below the helicopter and can weigh between 60–170 kg depending on the banner’s size. The system features a deadweight (approx 100 kg) which is composed of silica based sand to act as a stability control during flight. Helicopter banners can operate in constant wind speeds of up to 28 kt (52 km/h). Skybanners were the first ever helicopter banner company to be approved for over city flights, using the Skybanner Safety Systems.
In all jurisdictions around the world, the key issue for aviation authorities is the ability to safely jettison (release) the “deadweight” used to stabilize the banner system during flight.
Helicopter banners have been seen at many large sporting events including the FIFA World Cup in Germany, Tour de France and the London Marathon. They can fly for up to 3 hours at a time and are visible from 10 miles (16 km).