Sep 14, 2018
“More than a simple guard”
by Hendrik Thielemann
Taking off and landing on a grass or gravel runway requires a robust aircraft. Even as resilient as the Dornier 228 is, there can be advantages to having additional protection.
For some pilots, landing on unpaved runways is nothing out of the ordinary and may even seem an exciting prospect. For others, the bumpy experience can be quite a shock to the nerves. Interestingly, more than half of the world’s 42,000 airstrips are unpaved.
Despite it being an everyday task for many Dornier 228 pilots, landing on unpaved runways can still pose certain challenges. With dust and rocks flying around, there is always the risk of damage to the aircraft and its paintwork. If you recently got a cool new paint job, damage caused by such debris could be really nnoying, as well as costly.
“Equipping an aircraft to land on an unpaved runway involves much more than just attaching a set of protective fenders,” says Jörg Wittmer, who represents the Dornier 228’s customer service provider, RUAG Aviation in Oberpfaffenhofen, Germany. “There are all sorts of places that an aircraft requires protection from debris.” The landing gear’s actuators and hydraulic lines are particularly exposed during gravel landings and the underside of the fuselage, the tailplane and the aircraft lights also require special attention.
This is why operators all around the world use gravel kits, special equipment that protects the aircraft from the damage caused by repeated landings on unpaved surfaces. Norway’s Lufttransport AS, for instance, has fitted out both of its Dornier 228 aircraft with gravel kits to support landings on gravel, and even on snow for serving its routes on Svalbard. GAM used the gravel kit to help it reach the town of Taroom in Queensland, Australia on a gravel runway some 1,100 meters long. Other operators using gravel kits include the German Navy who, like other special mission aircraft, use the gravel kit to protect their selected equipment. Important mission equipment such as 360 ° radar antennae, radomes and/or electro-optical and infrared turrets need protection from stones that can potentially be stirred up by the front gear. Air Marshall Islands, who serves destinations in the South Pacific, have even seen landing strips made out of coral.
Operators can customize the solution to best suit the environmental conditions in which they operate. They can choose special paint finishes and coatings to protect the fuselage and landing gear, and to have the edges of the landing gear door and tailplane reinforced to improve their durability, if required. Special fenders that prevent the wheels from kicking up debris that hit the aircraft during take-off and landing are also available. Given that the lights are an integral part of aircraft, the range of protective options also includes robust light covers.
Today, RUAG Aviation offers the gravel kit as an option for new aircraft and as a retrofit solution for older Dornier 228 classic aircraft. For new generation Dornier 228 aircraft, careful consideration has been given to gravel landings, and the optimizations advanced accordingly. The new five-blade propellers of the Honeywell-TPE331 engines have a smaller diameter compared to their predecessors; this increases the distance between the propeller and the ground. The gravel kit is more than just a simple guard; it consists of multiple solutions that can be selected to suit specific terrain. Whether it is required for touchdowns on the hot and rocky terrain typical of Australia or Somalia, or on snow and ice in Norway or Canada – the gravel kit improves landing safety.
Dornier 228 landing on a dirt runway in San Juan de Manapiare, Venezuela.