Dornier 728

Dornier Do 728
Type:	Twin - engine narrow-body aircraft
Design country:	BR Germany
Manufacturer:	Dornier works
First flight:	Project termination after rollout
Number of pieces:	3 prototypes (one largely ready to fly)

The Dornier 728 was a twin- engined, narrow -body aircraft for short-haul flights, but it did not go into production; development had to be stopped a few months before the first flight of a prototype. The Dornier 728 was designed for 70 to 85 passengers and should compete with the Embraer 170 and Bombardier CRJ700 models . Care was taken to ensure that the trunk cross-section was large.

history

Shell construction of a cockpit section of the Dornier 728

The aircraft was developed by the then Dornier Luftfahrt GmbH under the ownership of Fairchild Dornier. Apart from the fact that the developers were engineers taken over by Dornier and that production took place at the former Dornier site in Oberpfaffenhofen, the project had practically nothing to do with Dornier GmbH in Friedrichshafen. After the complete takeover, Fairchild had even deleted the name affix Dornier, but reintroduced it because of the better recognition on the market. Lufthansa had already signed an option for 60 aircraft.

The rollout of the first prototype took place on March 21, 2002; the first test flight ( maiden flight ) did not take place due to the interim insolvency of the Fairchild Dornier company. The terrorist attacks on September 11, 2001 and the ensuing air transport crisis also affected the aviation industry. The relatively small company was dependent on donors and customer commitments, who only invested restrictively or withdrew purchase commitments due to the attacks.

Three prototypes were built as part of the 728 program . The most fully equipped and at the time of the first bankruptcy shortly before the first flight was TAC 71 (Test Aircraft 728 No. 1). In this prototype, in addition to all systems (in the meantime even the engines), extensive flight test cabling and instrumentation was also installed. In 2002 the project seemed to have already failed when Fairchild-Dornier , as the Dornier works were officially called after the takeover by Fairchild in 1996, filed for bankruptcy - not least because of the immensely increased development costs for the 728. After the entry of the Chinese D ' Long Corporation, Project 728 was resumed. Under the new management, all systems of the TAC 71 were also put into operation and tested (“Power On”); a first flight was announced for autumn 2004, the start of the scheduled service was planned for 2006. In July 2004, Fairchild-Dornier was finally insolvent, whereupon the property of the company was auctioned off in February 2005.

Four to five prototypes (TAC 71 to TAC 75) were planned for the flight tests in Oberpfaffenhofen and Granada .

After bankruptcy

Before the auction, most of the systems were expanded by the respective suppliers.

The first prototype TAC 71 was sold to DLR for 19,000 euros as part of the auction of the bankruptcy estate. It is used in Göttingen for tests of cabin acoustics and air flow. The dismantling was completed at the end of June 2005. The tail units and other add-on parts were dismantled, the wings sawed off at about the height of the pylons , as more careful riveting of the structure would have been too time-consuming. The remaining fuselage with wing stubs is around six meters wide and was in Oberpfaffenhofen until it was transported in autumn 2005. The condition then and now is documented at the DLR Institute for Aerodynamics in Göttingen.

The second prototype TAC 72 essentially only consisted of the cell and parts of the cabling and installations that had to be carried out very early. A former Dornier employee bought it for 6,000 euros. For many years it stood on a plate in Oberpfaffenhofen without windows, cockpit windows, doors and tail unit. The chassis was the manufacturer BFGoodrich in the leasing leave favorable. A development association that wanted to turn the cell into a Dornier museum had problems with the location or the transport to another. The German Museum of Technology in Berlin (DTMB) took over this prototype at the end of 2013. At Tempelhof Airport , the remaining parts of the fuselage, the wing center section including the engine nacelles and the outer wings are temporarily stored in the open air, in order to be able to illustrate modern aircraft construction methods as an exhibit in the DTMB in the future .

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  Fuselage of the Dornier Do 728 (2nd prototype TAC 72) at Tempelhof Airport

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  Dismantled wings of the Dornier Do 728 at Tempelhof Airport

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  Wing section of the Dornier Do 728 (near the pylon) at Tempelhof Airport

The third prototype built was intended as a break cell for the static structural test at IABG in Ottobrunn, where it was also scaffolded. It was set up in the test hall, which is why it also had to be dismantled so that it could be taken outside. Once upon a time there was talk that it could be used as a café, but this plan was probably too expensive.

There were also various structural parts for tests (e.g. fuselage bins) and from the stopped production, all of which were scrapped. This also included a dummy chassis and the tires.

Other planned versions

• Dornier 528 with a shortened fuselage as a competitor to the Bombardier CRJ200 .
• Dornier 928 with a stretched fuselage as a competitor to the Bombardier CRJ900 and Embraer 190 .
• Dornier 728 Envoy 7 : A company aircraft version with additional tanks in the fuselage to increase range, an increased maximum take-off weight of 39.5 tons and raked wingtips .

Technical specifications

Since this type of aircraft never flew, some of the details are only projected values.

Parameter	Dornier 528	Dornier 728	Dornier 928
First flight (projected)	?	2002	?
Commissioning (projected)	?	2004	?
length	23.10 m	27.40 m	31.01 m
span	26.26 m	27.12 m	28.81 m
Wing area	75 m²		84.4 m²
Cabin diameter	3.25 m
height	9.05 m		9.97 m
Empty mass	18,992 kg	20,900 kg	28,530 kg
Max. Takeoff mass ( MTOW )	31,890 kg	35,200 kg	47,560 kg
Max. Passenger capacity	63	80	110
Engine types	2 General Electric CF34 -8D3- turbofan - jet engines
thrust	52.5 kN	55.9 Envoy 7: 58.1 kN	75.6 kN
Cruising speed	828 km / h
Top speed	860 km / h
Service ceiling	12,497 m
Range	2,963 km	3,300 km	3,565 km

Web links

Commons : Fairchild Dornier 728  - Collection of images, videos and audio files

• Airliners.net data sheet about the 728
• Aerospace technology article
• 728 Jet Engineering Simulator
• airliners.net: The first prototype at the rollout on March 21, 2002 with mounted engines
• airliners.net: View of the first prototype without engines at the auction on February 15, 2005
• airliners.net: View of the second, partially assembled prototype at the auction on February 15, 2005
• airliners.net: The cockpit during the rollout on March 21, 2002
• airliners.net: The cockpit at the auction on February 15, 2005

Individual evidence

1. ↑ DLR brochure on Do 728
2. ^ Do 728 as a test vehicle
3. ↑ Dornier Do 728 Jet at the DTMB. In: Klassiker-der-luftfahrt.de. November 8, 2013, accessed July 11, 2015 .