Engineering:Akaflieg Stuttgart FS-23
| FS-23 Hidalgo | |
|---|---|
| Role | Glider aircraft |
| National origin | Germany |
| Manufacturer | Akaflieg Stuttgart |
| Designer | R. Eppler & H. Nägele |
| First flight | 1 February 1966 |
| Number built | 1 |
The Akaflieg Stuttgart FS-23 Hidalgo was a glider aircraft that was designed and built in Germany from 1953. It was lighter than most contemporaries. Only one example of the design was constructed, and it ended its career in a fatal crash in 1971.
Development
Design of the FS-23 was started in 1953 and took thirteen years, including a hiatus while the Akaflieg Stuttgart FS-24 Phönix was developed. The goal of the FS-23 designers was a lightweight high-performance glider to meet the proposed 13m mini-standard class for competition gliders. To achieve this goal the students at Akaflieg Stuttgart thoroughly tested fibreglass re-inforced composites, as well as birch ply and balsa/fibreglass sandwiches, for E- and G-modulus, compressive and torsional strength as well as bonding and rivetting methods. Once the testing was complete the aircraft could be designed to ensure adequate strength with light weight, (1/3 to 2/3 the weight of typical gliders of the time), and good aerodynamic qualities, the result being the FS-23 Hidalgo. Built primarily of balsa core sandwiched in fibreglass, the FS-23 was a high-wing, high aspect ratio, cantilever monoplane with moderate dihedral and -6o sweep, (to reduce the tail moment required and thus the size and weight of the rear fuselage and tail unit), and a V-tail. A fixed undercarriage and a brake parachute were used. Flight trials began on 1 February 1966 demonstrating that the FS-23 had sensitive controls, side-slipped well and gave adequate warning of a stall. It recovered easily from a spin, within half a turn. In 1967 the FS-23 suffered severe tail flutter and the pilot was thrown out of the cockpit, descending by parachute, as the aircraft dived towards the ground from 1500 meters altitude. The aircraft landed with minimal damage and was repaired to continue the test programme until July 1971 when the FS-23 crashed a second time, with the pilot, Heinz Jahn, losing his life.
Specifications
Data from http://www.uni-stuttgart.de/akaflieg/index.php?id=44&L=2
General characteristics
- Crew: 1
- Length: 5 m (16 ft 5 in)
- Wingspan: 13 m (42 ft 8 in)
- Height: 0.89 m (2 ft 11 in)
- Wing area: 7 m2 (75 ft2)
- Aspect ratio: 24.1
- Wing profile: FX 61-184 bei (root) / FX 61-168 bei (23% semispan) / FX 61-147 bei (70%) / FX 60-126 bei (88%)
- Empty weight: 102.5 kg (226 lb)
- Gross weight: 190 kg (419 lb)
Performance Armament
See also
Aircraft of comparable role, configuration and era
- Standard Austria
Related lists
References
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