Dornier Seastar

Seastar
Role	Utility amphibian
National origin	Germany
Manufacturer	Dornier Seawings Company
Designer	Claudius Dornier Jr
First flight	17 August 1984
Number built	2
Unit cost	$3.8 million (1998).[1] $6 million (2008)[2]

The Dornier Seastar is a turboprop-powered amphibious aircraft built largely of composite materials. Developed by Claudius Dornier Jr of Germany, it first flew in 1984. The design is owned by Claudius Jr's son, Conrado, who founded Dornier Seawings AG (now Dornier Seawings Company) to continue work on the project after two previous firms, Claudius Dornier Aircraft and Dornier Composite Aircraft, both went into bankruptcy. Development of the aircraft was put on hold without any production Seastars being completed in 1991.

Multiple attempts to put the Seastar into production, often as a joint venture with other aerospace companies, were made throughout the 1990s and early 2000s, however securing the necessary financing to proceed to the manufacturing phase proved challenging. After several false starts, in October 2009, Dornier Seawings announced that it was formally launching manufacturing of the type.

Development

Origins

The first prototype, a proof-of-concept aircraft using the metal wings from a Dornier Do 28 and with large struts bracing the wing to the sponsons, conducted its maiden flight from Hamburg on 17 August 1984.^[3] A second prototype, which was more representative of the definitive design, featured several alterations; these included the adoption of a new composite wing, which connected with a set of cabane struts to the fuselage only, and was a larger aircraft overall. On 24 April 1987, the second prototype made its first flight from Oberpfaffenhofen. Development work on the project came in a close in 1991.^[1] A total of three aircraft had been produced at this point.^[2] In 1990, a European certificate of airworthiness was received for the type; in 1991, American airworthiness was also granted to the Seastar.^[4][5]

During the 1990s, the programme encountered severe organisational issues, including a lack of funding and backers who subsequently withdrew their participation.^[6][1][7] In November 1989, the company behind the Seastar, Claudius Dornier Aircraft, filed for bankruptcy, amid claims that the German government had failed to support the project. Prior to this, more than 50 options and letters of intent had been received for the type.^[1] In 1990, Dornier Composite Aircraft acquired the Seastar program, but this firm was also bankrupt within two years. As a result, a new company, Dornier Seastar, was formed to complete the aircraft's development and to produce the type, and began to seek partnerships with Asian companies to achieve this.^[1][7]

In 1993, Dornier Seastar and a consortium of Malaysian investors signed an joint venture agreement, under which assembly of the Seastar was envisioned to take place at a factory in Malaysia within the following year. However, in July 1995, a company spokesperson stated that Dornier Seastar's Malaysian subsidiary would be shelved until further notice due a lack of capital investment; it has been allegedly that investors were concerned about the technical and financial viability of the project, such as the acquisition of internationally-recognised production certification in Malaysia.^[6][8] By the time of the withdrawal, all of the manufacturing tools, moulds and jigs to produce that aircraft had already been transferred to Penang, Malaysia, along with a prototype aircraft for sales demonstration purposes at Subang Airport, Selangor.^[6]

Following the collapse of the Malaysian joint venture, Dornier Seastar promptly set about attracting new investors to finance the program into the manufacturing phase. While the company focused its search on the Asian market, representatives stated that they were considering relocating production of the type to another country; Dornier Seastar also dismissed claims that a further $100 million was required to complete development of the aircraft's design.^[9] In early 1998, Dornier Seastar proposed the formation of a partnership with Hindustan Aeronautics (HAL), with the goal of producing the type as a joint venture.^[1][7] HAL confirmed that it was examining the viability for the Seastar in the Indian market.^[10]

By 2003, one of the two Seastar prototypes had been restored and received public transport certification in December of that year.^[7] In February 2004, the company stated that, in addition to seeking investment, it had been evaluating potential manufacturing sites in Europe and Asia prior to initiating a planned development phase later that year.^[7] It was said that feasibility studies and market analysis indicated that there was a global demand for around 250 such aircraft over the next ten years; furthermore, that it was proposing three different versions of the aircraft, each one for a different market segment: A survillance variant for government agencies, a 12-seat regional airliner configuration aimed at charter operators, and a six-seat layout that was suited to VIP customers.^[7] In August 2006, there were claims made that the project was close to being re-launched with backing from firms in Singapore and Abu Dhabi, the latter being contingent upon the Seastar being manufactured in Abu Dhabi.^[11]

In October 2008, the company announced its intentions to produce the Seastar in the US, in part due to favourable currency exchange rates.^[2] Fabrication was to be outsourced to other companies, and was intended to mainly use American suppliers. The firm viewed the aircraft as having a niche role among private owners, airlines, and search and rescue operators.^[2] Dornier Seawings stated that it was seeking an additional $150 million to bring the type into mass production; it was also said that, in the event of 25 or more sales being secured, the Seastart could be in production as early as March 2009.^[12] In March 2009, the firm stated that it was pushing back its planned launch to the third quarter of that year, attributing this to the effects of the Great Recession, but remained optimistic about market demand for the type; it was also said that Dornier only required an additional $65 million, rather than the $150 million figure given in an earlier business plan, to establish full production status and to begin manufacturing work.^[4]

Launch

In October 2009, Dornier Seaplane announced that it would launch production of the Seastar.^[13] According to Dornier Seaplane chief executive Joe Walker, the aircraft had been well received by a variety of public and private operators, and had received more than 25 letters of intent to procure the Seastar; he also stated that 2010 would be dedicated to selecting a final assembly site and major suppliers for the aircraft's manufacturing, the first aircraft was then scheduled to be rolled-out by the end of 2011.^[5]

In May 2010, Dornier Seaplane announced that it would build the Seastar in Saint-Jean-sur-Richelieu, about half an hour away from Montreal, Quebec, Canada.^[14] The site was picked due to the strength of the local supply chain and presence of skilled aerospace workers, as well as its proximity to Lake Champlain for flight operations. At this point, the company aimed to deliver their first production aircraft in 2012; production was project to rise from a single aircraft in 2012, to six in 2013 and to 12 in 2014; dependent on demand, as many as 50 Seastars per year could eventually be being built.^[15][16]

The company has since become a joint venture involving two Chinese state owned companies and plans to produce the aircraft in two locations, with one site in Oberpfaffenhofen, Germany and another in Wuxi, China.^[17]

In January 2016, Dornier Seaplane announced that Seastar airframes would be built by Diamond Aircraft Industries.^[18]

Design

Seastar, 2010

The Dornier Seastar is a parasol wing flying boat, powered by a pair of two Pratt & Whitney Canada PT6A-112 engines mounted in a single nacelle over the wings in a push-pull configuration. In general layout, it strongly resembles both the innovative Dornier Wal all-metal monoplane flying boat of the 1920s, of which over 250 examples were built; and its direct successor, the larger Dornier Flugzeugwerke's Do 18 of the 1930s. Locating both of the engines in the center of the wing enables the weight of the engines to be more effective in reducing any induced rolling motions; it also protects the engines themselves from water spray, reducing corrosion, and eliminates asymmetric thrust when operating.^[19]

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.^[2][19] Unlike a typical floatplane, 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.^[19] The sponsons, which provide stability while submerged in 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, where as other flying boats often retract the landing gear into the hull instead.^[19] 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.^[19]

The hull of the Seastar features complex angling and shaping as of the result of extensive water tank testing.^[19] Pilots exit and enter the Seastar through a single door on the left-hand side of the aircraft from the sponson, passengers board via a separate hatch located aft of the wing, also stepping from the sponson.^[19] This approach enables the aircraft to close to a relatively short distance from docks or boats for boarding purposes. The cabin is can house up to 12 passengers in addition to the crew in high-density seating, or can alternative accommodate six-to-nine passengers in more spacious configurations; an aft baggage compartment is also present.^[19]

A series of improvements have been projected for the aircraft, such as the integration of an autopilot to enable single-pilot operations.^[2] Other prospective improvements include the adoption of a glass cockpit, de-icing equipment, and air conditioning systems.^[12] Early production aircraft are intended to be compatible with the retrofitting of these improvements later on.^[5] According to Dornier Seawings, the Seastar's flight endurance can be extended by cruising on only a single engine to around 11 flight hours for surveillance missions.^[7] It is also claimed that the Seastar is one of the fastest flying boats on the market.^[2]

Variants

Seastar CD-2 

Specifications (Seastar CD-2)

The Dornier Seastar on the Wolfgangsee in Austria

Rearview of a Seastar

Data from Jane's All The World's Aircraft 1988-89^[20]

General characteristics

• Crew: One or two
• Capacity: 12 passengers
• Length: 12.46 m (40 ft 10½ in)
• Wingspan: 15.50 m (50 ft 10¼ in)
• Height: 4.60 m (15 ft 1 in)
• Wing area: 28.48 m² (306.6 ft²)
• Empty weight: 2,400 kg (5,291 lb)
• Gross weight: 4,200 kg (9,259 lb)
• Powerplant: 2 × Pratt & Whitney Canada PT6A-112, 373 kW (500 hp) each each

Performance

• Cruising speed: 341 km/h (212 mph)
• Stall speed: 115 km/h (72 mph)
• Range: 1,850 km (1,150 miles)
• Endurance: 9 hours  12 (One engine) min
• Service ceiling: 8,535 m (28,000 ft)
• Rate of climb: 8.0 m/s (1,575 ft/min)
• Takeoff Distance to 15 m (50 ft): 410 m (1,345 ft)
• Landing Distance from 15 m (50 ft) (on land): 480 m (1,575 ft)

See also

Aircraft of comparable role, configuration and era

• Dornier Do 18
• Dornier S-Ray 007

Related lists

• List of seaplanes and amphibious aircraft

References

Citations

Bibliography

External links

Wikimedia Commons has media related to Dornier Seastar.

• Dornier Seaplane Company
• http://www.flugzeuginfo.net/acdata_php/acdata_cd2_en.php
• "SEASTAR" Aviation&Weekly Video