The history of Dornier and amphibians goes back a century and the innovative Dornier Wal all-metal monoplane flying boat of the 1920s, of which over 250 examples were built as well as the larger Dornier Flugzeugwerke's Do 18 of the 1930s.
It was in these two flying boats that Dornier pioneered the concept of locating the two engines in a puller and pusher configuration housed in the same nacelle in the center of the parasol wing. This placement enabled the weight of the engines to be more effective in reducing any induced rolling motions and it also protected the engines from water spray, reducing corrosion, and eliminates asymmetric thrust when operating.
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So, when in early 1980s Claudius Dornier Aircraft announced plans to bring a new amphibian to the market it came as no surprise that the parasol wing flying boat's, pair of Pratt & Whitney Canada PT6A-112 engines would be mounted in a single nacelle over the wings in a push-pull configuration.
Designed by Claudius's son Conrada the first prototype using the metal wings from a Dornier Do 28 and with large struts bracing the wing to the sponsons, had its first flight on 7 August 1984. The second prototype, a larger aircraft overall, featured several improvements including the adoption of a new composite wing which connected with a set of cabane struts to the fuselage only flew on 24 April 1987.
In 1990, a European certificate of airworthiness was received for the type and in 1991, American airworthiness was also granted. Despite more than 50 options and letters of intent for the purchase of the aircraft because of severe organisational issues and a lack of funding in November 1989 Claudius Dornier Aircraft, filed for bankruptcy.
Numerous attempts throughout the 1990s and early 2000s to revive the project, often involving joint ventures, led nowhere. A new company, Dornier Seastar, was formed to complete the aircraft's development and to produce the type. In 1993, Dornier Seastar announced that it had signed an agreement with a consortium of Malaysian investors signed a joint venture agreement, under which assembly of the Seastar was envisioned to take place at a factory in Malaysia. However, due to a lack of capital this venture came to naught.
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In 2003 Dornier Seastar somehow managed to restore the second protype and a received public transport certification in December of that year. Still seeking investors or joint partners the company in October 2008 announced that due to the favorable currency exchange rates its intents producing the Seastar in the US. In October 2009, announced that the aircraft had been well received by a variety of public and private operators, and that it had received more than 25 letters of intent to procure the Seastars to be build in a factory in Saint-Jean-sur-Richelieu, about half an hour away from Montreal, Quebec, Canada. This also did not happen.
In 2013, the Dornier family sold a majority share in the company to two Chinese companies; Wuxi Communications Industry and Wuxi Industrial Development. As part of the agreement production would take place in Oberpfaffenhofen, Germany and another in Wuxi, China. However, in January 2016, Dornier Seaplane announced that Seastar airframes would be built by Diamond Aircraft Industries and the first new-generation Seastar rolled out on 18 August 2017 in Oberpfaffenhoffen and on 28 March 2020 the CD2 prototype made its first flight.
The Seastar CD2 included a redesigned and upgraded interior, Honeywell Primus Epic 2.0 avionics, a stern thruster, new Sumitomo corrosion-resistant landing gear, hydraulic electrically steerable nose gear, MT five-blade composite propellers and Pratt & Whitney Canada PT6A-135As.
The Seastar's fuselage is composed of a fiberglass composite material, which is corrosion-proof as well as being less prone to leaks in comparison to rivetted metal hull counterparts. Unlike typical floatplanes, which are often conversions of land-based aircraft, the Seastar has a low vertical center of gravity, achieved in part by carrying all of its fuel within its sponsons instead of the wings. The sponsons, which provide stability while submerged on the water, are shaped to break surface tension and to generate considerable lift during the acceleration performed during takeoff; they also accommodate the main landing gear. Other flying boats often retract the landing gear into the hull instead. The landing gear can be optionally removed and reinstalled when needed; a special 'water mode' for the landing gear is also present which prevents their deployment during a water-based landing.
The hull of the Seastar features complex angling and shaping, as the result of extensive water tank testing. Pilots exit and enter the Seastar through a single door on the left-hand side of the aircraft from the sponson, and passengers board via a separate hatch located aft of the wing, also stepping from the sponson. This approach enables the aircraft to close to a relatively short distance from docks or boats for boarding purposes. The cabin can house up to 12 passengers, in addition to the crew in high-density seating, or can alternatively accommodate six-nine passengers in more spacious configurations; an aft baggage compartment is also present.
The Seastar is being aimed at multi-mission markets, including coastal patrolling and surveillance, fisheries protection, environmental control, emergency medical services, search and rescue, drug interdiction and disaster relief.
Entry into service is planned for 2021.