# Schempp-Hirth Discus > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Schempp-Hirth_Discus > Markdown URL: https://mediated.wiki/source/Schempp-Hirth_Discus.md > Source: https://en.wikipedia.org/wiki/Schempp-Hirth_Discus > Source revision: 1269064546 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) German single-seat glider, 1984 This article needs more citations. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Schempp-Hirth Discus" – news · newspapers · books · scholar · JSTOR (May 2009) (Learn how and when to remove this message) Discus General information Type Standard-class sailplane Manufacturer Schempp-Hirth Designer Klaus Holighaus Number built >850 History First flight 1984 The **Schempp-Hirth Discus** is a [Standard Class](/source/Glider_competition_classes) [glider](/source/Glider_(sailplane)) designed by [Schempp-Hirth](/source/Schempp-Hirth). It was produced in [Germany](/source/Germany) between 1984 and 1995 but has continued in production in the [Czech Republic](/source/Czech_Republic). It replaced the [Standard Cirrus](/source/Schempp-Hirth_Standard_Cirrus). It was designed by [Klaus Holighaus](/source/Klaus_Holighaus). ## Design and development The Discus was the first production sailplane to have a distinctive swept-back leading edge. This is now common in contemporary sailplanes. Studies had long shown that the ideal wing for minimizing [induced drag](/source/Induced_drag) should be an elliptic planform. To keep production costs down, a triple-trapezoidal approximation of this shape was adopted for the Discus. The wing section was also new. [Winglets](/source/Wingtip_device) were only available towards the end of the production run, though many have been retro-fitted. The fuselage and tail were adapted from the [Schempp-Hirth Ventus](/source/Schempp-Hirth_Ventus). A version with a narrow fuselage is called the Discus 'a' and the wider fuselage version is called the 'b'. The fuselage is made of [glass-reinforced plastic](/source/Glass-reinforced_plastic) around a steel tube frame. The wings and tail surfaces are also fiberglass with the exception of the main wing spar, which is made of [carbon fiber](/source/Carbon_fiber). There is a 6.5 L (1.7 US gal; 1.4 imp gal) water ballast tank in the fin for trimming purposes when the main wing mounted ballast tanks are in use (184 L combined) for a maximum wing-loading of 50 kg/m2 (10 lb/sq ft) ### Competition use The Discus dominated standard class sailplane racing throughout the 1980s, winning six [World Gliding Championships](/source/World_Gliding_Championships) in a row from 1985 to 1995. ### Performance The best measured [glide ratio](/source/Glide_ratio) is 42.5:1. Though it is considered a high performance sailplane, its handling is well within the capabilities of inexperienced pilots. With no bad manners, powerful airbrakes and a low landing speed, the Discus is popular with clubs. Discuses are easy gliders to assemble, having light wings, automatic control hookups and a single pin securing the wings. ### Production Over 850 Discuses had been built by 2004 and it remains in production today despite the introduction of its successor, the [Schempp-Hirth Discus-2](/source/Schempp-Hirth_Discus-2). About 12 per year are built under license by Schempp-Hirth Vyroba in the [Czech Republic](/source/Czech_Republic) as the Discus CS. Some models are fitted with small sustaining engines (turbos) and are designated Discus T. ## Variants **Discus a** - Short fuselage and narrow cockpit optimized for smaller pilots, utilising the fuselage and tail of the [Ventus a](/source/Schempp-Hirth_Ventus). **Discus b** - Standard production model utilizing the fuselage and tail of the [Ventus b](/source/Schempp-Hirth_Ventus). **Discus bT** - Discus b with a retractable sustainer motor **Discus bM** - Motor-glider with retractable engine **Discus CS** - Continued production in the [Czech Republic](/source/Czech_Republic) **Discus K** - Aerobatic version first flown on 18 November 1987. This was, due to disappointing performance in aerobatic, later converted back to a standard version.[1] ## Specifications (Discus b) Instrument panel in a Discus CS. *Data from* *Jane's All the World's Aircraft 1988-89* [2] **General characteristics** - **Crew:** 1 - **Length:** 6.68 m (21 ft 11 in) - **Wingspan:** 15 m (49 ft 3 in) - **Height:** 1.27 m (4 ft 2 in) - **Wing area:** 10.58 m2 (113.9 sq ft) - **[Aspect ratio](/source/Aspect_ratio_(aeronautics)):** 21.3 - **Empty weight:** 233 kg (514 lb) - **Max takeoff weight:** 525 kg (1,157 lb) - **Water ballast:** 180 L (48 US gal; 40 imp gal) **Performance** - **Stall speed:** 66 km/h (41 mph, 36 kn) - **[Never exceed speed](/source/V_speeds#VNE):** 250 km/h (160 mph, 130 kn) in smooth air - - - - 200 km/h (110 kn; 120 mph) in rough air - 180 km/h (97 kn; 110 mph) on aero-tow - 150 km/h (81 kn; 93 mph) on winch launch - **g limits:** +5.3 - 2.65 - **Maximum glide ratio:** 45:1 at 100 km/h (54 kn; 62 mph) - **Rate of sink:** 0.59 m/s (116 ft/min) at 78 km/h (42 kn; 48 mph) - **Wing loading:** 49.62 kg/m2 (10.16 lb/sq ft) ## See also **Aircraft of comparable role, configuration, and era** - [Glaser-Dirks DG-300](/source/Glaser-Dirks_DG-300) - [PZL Bielsko SZD-55](/source/PZL_Bielsko_SZD-55) - [Rolladen-Schneider LS4](/source/Rolladen-Schneider_LS4) - [Schleicher ASW 24](/source/Schleicher_ASW_24) **Related lists** - [List of gliders](/source/List_of_gliders) ## References 1. **[^](#cite_ref-1)** Thomas Bergmann. ["Discus"](https://web.archive.org/web/20190401074802/https://www.segelfliegen-magazin.de/wp-content/uploads/2013/05/discus.pdf) (PDF) (in German). Archived from [the original](https://www.segelfliegen-magazin.de/wp-content/uploads/2013/05/discus.pdf) (PDF) on 2019-04-01. 1. **[^](#cite_ref-JAWA88-89_2-0)** John W.R. Taylor, ed. (1988). *Jane's All the World's Aircraft 1988-89*. London: Jane's Information Group. p. 630. [ISBN](/source/ISBN_(identifier)) [0-7106-0867-5](https://en.wikipedia.org/wiki/Special:BookSources/0-7106-0867-5). - Simons, Martin (2005). *Sailplanes 1965-2000* (2nd revised ed.). Königswinter: EQIP Werbung und Verlag G.m.b.H. [ISBN](/source/ISBN_(identifier)) [978-3-9808838-1-8](https://en.wikipedia.org/wiki/Special:BookSources/978-3-9808838-1-8). ## External links Wikimedia Commons has media related to [Schempp-Hirth Discus](https://commons.wikimedia.org/wiki/Category:Schempp-Hirth_Discus). - [Schempp-Hirth Website](http://www.schempp-hirth.com/) - [A Flight Test Evaluation of the Discus Sailplane, by R.H. Johnson, published in Soaring Magazine, February 1986](http://www.harrishillsoaring.org/doc/discus_johnson.pdf) - [British Gliding Association, Discus datasheet](http://www.gliding.co.uk/bgainfo/technical/datasheets/discus.pdf) - [Specifications of Schempp-Hirth Discus](https://web.archive.org/web/20051102092646/http://www.sailplanedirectory.com/PlaneDetails.cfm?planeID=87) v t e Schempp-Hirth gliders Wooden construction Göppingen Gö 1 Göppingen Gö 3 Göppingen Gö 4 Göppingen Gö 5 Göppingen Gö 8 Göppingen Gö 9 Minimoa SHK Standard Austria GRP construction Arcus Discus Discus 2 Duo Discus Janus Nimbus Nimbus 2 Nimbus 3 Nimbus 4 Mini-Nimbus Open Cirrus Quintus Standard Cirrus Ventus Ventus-2 Ventus-3 --- Adapted from the Wikipedia article [Schempp-Hirth Discus](https://en.wikipedia.org/wiki/Schempp-Hirth_Discus) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Schempp-Hirth_Discus?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.