Akaflieg Stuttgart fs 35
| Akaflieg Stuttgart fs 35 | |
|---|---|
| Type: | Touring motor sailer |
| Design country: | |
| Manufacturer: |
Akaflieg Stuttgart |
| First flight: |
13th August 2019 |
| Number of pieces: |
1 prototype |
The Akaflieg Stuttgart fs 35 "Harpy" is a two-seater touring motor glider Akaflieg Stuttgart in CFK - sandwich construction .
History and construction
The “ Harpyie ” was created by the Stuttgart Academic Aviation Group in 2003 as a motor glider designed for aircraft towing with good climbing performance and a large fuel tank, after Porsche had announced the discontinuation of model support for the PFM 3200 aircraft engine for 2005. This engine was installed in the club's Robin DR 400 tow plane . The following requirements were defined: high aerodynamic quality in aircraft towing in the speed range 90–150 km / h, short take-off roll distance, use of an efficient diesel engine , approval as a motor glider and design as a two-seater with double steering for the possibility of training.
The design of the wing began with the assumption of 120% of the fuselage resistance of the Diamond HK36 Super-Dimona and the drive with a Thielert Centurion 1.7 with 125 HP (approx. 90 kW). The two-part Dimona wing was chosen, which was extended inwards, swept and provided with winglets . In April 2007, the molding of the three-part half-span master model began and in 2009 the construction of the fracture wing with integrated strain gauges in the resulting negative form. A load test of this component on November 4, 2010 failed because the wing broke at 80% of the load to be verified. The wing construction began after reinforcement of the original construction and its mathematical proof of strength in April 2011.
The wing consists of a CFRP sandwich shell with CFRP straps and a GRP web. The I-shaped spar merges into a box spar in the spar stub.
The fuselage is also based on the Dimona, but the position of the wing had to be moved forward because of the heavier engine. The four-cylinder in-line engine Centurion 2.0s, now known as the Continental CD-155, serves as the drive as a further development of the Centurion 1.7.
The vertical tail of the Dimona was built with the Eppler profile E 522 and increased profile depth as a GRP shell with CFRP belts in the spar. At the end of the fuselage tube, a tow coupling is installed on a boom under the tail unit.
The main landing gear comes from the Van's Aircraft RV-8 , the nose landing gear from the Super Dimona.
The first flight took place on August 13, 2019 in Schwäbisch Hall .
Technical specifications
| Parameter | Data |
|---|---|
| crew | 1 + 1 |
| span | 17.67 m |
| Wing area | 16.9 m² |
| Wing extension | 18.5 |
| Wing profile | FX 63-K-137 (mod) |
| V position | 3 ° |
| Empty mass | 600 kg |
| Max. Takeoff mass | 850 kg |
| Top speed | 270 km / h |
| Engine | a Continental CD-155, 155 PS (approx. 110 kW) |
See also
Web links
Individual evidence
- ↑ fs35 - Harpy. Akaflieg Stuttgart, August 2019, accessed on August 26, 2019 .
- ↑ Akaflieg Stuttgart (Ed.): Akaflieg Stuttgart - 90 years of research, building, flying. Prototype developments 1926–2016 . S. 358-395 .
- ↑ Lars Reinhold: First flight: Akaflieg Stuttgart brings fs35 into the air. In: aerokurier.de. August 15, 2019, accessed August 26, 2019 .