Akaflieg Köln LS11
__NOTOC__ Infobox Aircraft
name=LS11 or AFK1
caption=The LS11 prototype at the AERO2003 exhibition.
type=Two-seater- and Open-class sailplane
first flight=5 November avyear|2005
variants with their own articles=
The LS11 or AFK1 is a prototype Two-Seater Class
sailplanecurrently in development at Akaflieg Köln e.V.(Academic Flying Group of the University of Cologne). The maiden flight of the LS11 took place on November 5, 2005.
Design and development
Akaflieg Köln initiated in 2000 the concept design for the AFK1. One of the design goals was to use as many standard LS components as possible in order to lower the development costs. This and the large contribution of
Wolf Lemke, who performed the aerodynamic and structural calculations, led to Rolladen-Schneider bestowing the type designation LS11 upon the Akafliegers' project.
The goal of the project is to design and build a thoroughly capable school glider with top performance for cross-country training, record flying and competition.
The LS11 gets its performance from an extended LS6 wing. The
Akaflieg Darmstadt D41, a side-by-side two-seater whose first flight took place in 1993, demonstrated the feasibility of a high performance, multiplace glider based on the LS6 wing. The Akafliegers felt they could profit from and improve upon that design.
The wing structure was redesigned and resembles somewhat the LS9 structure. The wings, almost entirely made of Carbon Reinforced Plastic, were manufactured at the Rolladen-Schneider factory in
Egelsbachduring summer 2001, while the span extensions were built in the moulds developed by the Darmstadt group for the D41.
The LS11 prototype was featured as a work in progress at the 2003 and 2005 AERO
Friedrichshafenexhibitions in Germany. The maiden flight took place November 5, 2005, and was to be followed by a comprehensive flight test programme in 2006. The flight testing will be carried out at Akaflieg Köln's home airfield, Dahlemer Binzin the Eifelregion in Germany.
The LS11 is slated for production by the Slovenian aircraft manufacturer AMS-Flight. If this comes to fruition, this will possibly be the first prototype developed by a German academic association that reaches serial production.
The LS11 is expected to have up to four interchangeable sets of wingtips for spans between 18 and 21 meters. The prototype currently has a 20 meter span in keeping with the new Two-Seater competition class.
Water ballast bags inside the wings enable loadings up to 50 kg/m². Two ballast tanks integrated into the rudder fin will keep the
centre of gravitywithin its optimum range, compensating for ballast changes and heavier pilots.
The empty weight was a serious design concern for reasons beyond mere ease of ground handling. As the scope for increasing the wing area was limited (it being originally designed for a single seater), the Akafliegers strove to achieve an empty mass as low as possible, in order to keep the wing loading of the shorter 18 meter span within reasonable limits.
Some parts of the fuselage were adapted from existing production types, such as the tail boom of the LS4 and the empennage of the LS8. Considerable redesign was required, however. The span of the horizontal stabiliser was increased; the vertical stabiliser was made both taller and longer, to provide the required steering power while keeping the top of the vertical fin at a height comfortable for the assembly of the horizontal empennage.
The cockpit, manufactured from carbon and
aramidreinforced plastic, was designed to accommodate in full comfort pilots up to two meters tall. Available space is sumptuous for both pilots, exceeding that of all comparable production gliders. The front seat is similar to the LS4 cockpit, and both seats have enough leg and elbow room to preclude the mutual interference too often encountered in tandem sailplanes. The maximum cockpit load is a generous 230 kg.
The large canopy is implemented as a single unit integrating the instrument panels into the canopy frame. It is hinged at the back in the Piontkowski fashion and opens with an upward and rearward movement. The practicality of this concept for large glider canopies has already been tested by Akaflieg Köln through the modification of three
The hinge is a carbon reinforced element able to withstand wind speeds up to 75 km/h when open and was designed to sever the tubing and wiring looms from the instrument panels upon emergency release in flight.
The airplane stands on a sprung, retractable main
undercarriagewith a six-inch hub, and a nose wheel which is likewise sprung and retracts simultaneously with the main wheel. A fixed tail wheel is also provided. This undercarriage scheme simplifies ground handling, which can be easily accomplished without fuselage dollies, in particular as the main wheel is located near the glider's empty center of gravity.
All controls connect automatically upon assembly in the habitual LS way. The control system is built mostly from standard LS parts. The wings are held together by two main pins inserted into the tongue-and-fork
sparends, as in the LS6 and subsequent LS types.
A low landing speed is essential for a trainer.
Wolf Lemkeand Siegfried Piontowskidecided to depart from the typical LS system in which aileronsand flapsact as flaperons. A mixed schedule as in e.g. the ASW 27 was implemented. In landing configuration the flaps assume a deflection of about 75 degrees while the ailerons remain in a neutral position. This enables slower landing speeds with good control response. Multiblade airbrakes extend from the upper surfaces of the wings to give ample glidepathmodulation.
pecifications (with 18 metre span)
met or eng?= met
rot dia m=
rot dia ft=
rot dia in=
wing area sqm=13.4
wing area sqft=144
swept area sqm=
swept area sqft=
rot area sqm=
rot area sqft=
aspect ratio= 24.2
empty weight kg=ca. 360
empty weight lb=790
gross weight kg=670
gross weight lb=1,470
max speed kmh=
max speed mph=
max speed mach=
cruise speed kmh=
cruise speed mph=
glide ratio= 46 at 100 km/h (60 mph)
climb rate ms=
climb rate ftmin=
sink rate ms= 0.63
sink rate ftmin= 124
* [http://www.akaflieg-koeln.de Akaflieg Köln e.V.]
* [http://ls11-slideshow.akaflieg-koeln.de/ Pictures of first flight]
* [http://www.akaflieg-koeln.de/content/view/48/85/ Videos of the construction and maiden flight]
* [http://www.ams-flight.si/ AMS-Flight]
Wikimedia Foundation. 2010.
Look at other dictionaries:
Akaflieg Köln LS11 — Akaflieg Cologne projet LS11 Le LS11 ou AFK1 est un prototype de planeur biplace actuellement en projet à l Akaflieg de l université de Cologne (Section aéronautqiue de l université de Cologne). Le premier vol du LS11 fut effectué le 5 novembre… … Wikipédia en Français
Akaflieg — is an abbreviation for Akademische Fliegergruppe , an academic group of fliers in pre and postwar Germany. HistoryOtto Lilienthal published his book Der Vogelflug als Grundlage der Fliegekunst in 1889. This described the basics of modern… … Wikipedia
Akaflieg Cologne Projet LS11 — Le LS11 ou AFK1 est un prototype de planeur biplace actuellement en projet à l Akaflieg de l université de Cologne (Section aéronautqiue de l université de Cologne). Le premier vol du LS11 fut effectué le 5 novembre 2005. Sommaire 1 Historique 2… … Wikipédia en Français
Akaflieg Cologne projet LS11 — Le LS11 ou AFK1 est un prototype de planeur biplace actuellement en projet à l Akaflieg de l université de Cologne (Section aéronautqiue de l université de Cologne). Le premier vol du LS11 fut effectué le 5 novembre 2005. Sommaire 1 Historique 2… … Wikipédia en Français
Rolladen-Schneider LS6 — NOTOC The Rolladen Schneider LS6 is a 15 metre and 18 metre single seat flapped glider manufactured by Rolladen Schneider Flugzeugbau GmbH between 1984 and 2003.DevelopmentThe prototype of the LS6, successor to the LS3 in the FAI 15 metre Class,… … Wikipedia
Rolladen-schneider ls6 — Le Rolladen Schneider LS6 est un planeur monoplace de classe FAI 15 et 18 mètres, équipé de volet de courbure. Il fut fabriqué entre 1984 et 2003. Sommaire 1 Histoire 2 Description Générale … Wikipédia en Français
List of aircraft (N-S) — NOTOC N Naglo * Naglo D.II = Nakajima = * Nakajima A1N * Nakajima A2N * Nakajima A4N * Nakajima A6M2 N * Nakajima AT 2 * Nakajima B5N * Nakajima B6N Tenzan * Nakajima C6N Saiun * Nakajima E2N * Nakajima E4N * Nakajima E8N * Nakajima G5N Shinzan * … Wikipedia
Liste de planeurs — (en) Cet article est partiellement ou en totalité issu de l’article de Wikipédia en anglais intitulé « List of Gliders » (voir la liste des auteurs) Sommaire … Wikipédia en Français
Список Планёров — Содержание 1 Abbott Baynes Sailplanes Ltd 2 Abrial 3 Advanced Aeromarine 4 … Википедия
Список планёров — Содержание 1 Abbott Baynes Sailplanes Ltd 2 Abrial 3 Advanced Aeromarine 4 Advan … Википедия