Mü 13 "Merlin"
Motormerlin, motorglider
Length 6,0 m, span 16,0 m, wing
area 16,16 m2, aspect ratio 15,84
Empty 170 kg, max. flying weight 270 kg,wing loading 16,7 kg/m2
Max speed 160 km/h, gliding ratio 28 at 66 km/h, lowest descent 0,6 m/sec.
First flight July 21, 1934.The Mü 13 Merlin was modified by adding a Köcher - M4 Kröber engine 18 hp to the front
of the glider. Note that the retractable landing gear consists of two small wheels mounted diabolo after a fork 40 cm
to ensure the clearance of the propeller. The outlet pressure is dynamically moved by means of a pole on the right
wing outside of the disturbed path of the propeller area .
The technical information Mü 13 looks like a car at high cantilever wings. The canopy , made ​​of two purely trapezoidal parts , has a wingspan of 16 m and an elongation of 16; profile Mü 14% is derived from that used on the Milan and has a very rounded leading and a substantially flat bottom surface edge . The wing structure is composed of a main spar of the box made ​​of fir soles and souls against plywood type of oblique bar and drag a spar used to support joint flap and fin . The ribs constructed lattice strips of spruce are strung on the spar . Between the leading edge and spar , the root zone and the area between the rail and the drag bar is sheeted in plywood and ensure against the absorption of torsional forces , the rest of the wing is canvas . The leading edge of the root is part of the canopy and is covered rhodoïd to improve the horizontal visibility . The ends of the main beam are lined fittings crossed by a vertical axis which assembles wings together. Two brackets placed under the main beam and the drag bar allow the positioning and fixing of the wing to the fuselage . The trailing edge of the wing is held in the Atalante and Merlin versions , composed by the flaps and ailerons structure made ​​of steel tubes of fabric covered control surfaces . The flaps to improve lift and facilitate spiral landing flaps are connected with the part so as to differentially warping . On the standard version and the flaps are removed in favor of spoilers DFS intrados and extrados
History summarized Over the years 1936-38 , the Mü 13 had proved its indisputable qualities and it was decided to build it in the series of workshops Schwartzwald Flugzeugbau - Gesellschaft ( SFG ) in Donaueschingen . The series version designated Mü 13 D had a number of differences with the Merlin and Atalanta . The wing is now devoid of flaps but equipped with airbrakes DFS pressure side and suction while the fins are constructed of wood . The body remains unchanged with the exception of the side windows of which the dimensions are reduced and the landing gear of the present compound to a single larger diameter wheel which replaces the dolly wheel train of small diameter. The stabilizers are against seriously reworked . The vertical plane is now composed of a stump drift and a lower rudder surface. The horizontal plane is enlarged and consists of a stabilizer cased and an elevator entoilée .
It is with 13D Mü Schmidt enlisted in 1938 in the stage race Sylt , Kiel, Altona, Hagenow, Wittenberg , Brandenburg , Berlin, Rangsdorf Kottbus , Sorau , BresIau (810 km) and managed to get there rank second behind Hanna Reitsch . He also participated in the 19th Rhön contest where he made a flight of 410 km , which allowed him access to 5th place. Finally in 1939 , the last year of peace, devoted glory Schmidt and Mü 13D with first, from 18 June to 8 July, the Freiburg- Stettin race (840 km) crossing Germany from west to east . Of the 22 competitors joined the fray , only 14 attinrent purpose. Schmidt was the first to Braeutigam on Weihe and Flinsch Darmstadt D 30 . Then came the 20th Rhön which was the occasion of a fantastic duel between Schmidt Mü 13D and Erwin Kraft Condor III . After 14 days of fierce battle , Kraft beat Schmidt with 17 points ahead of a total of 2550 . The war was to stop the adventure of Mü 13 and that was great driver Kurt Schmidt. It was incorporated into the DFS (Deutsche Forschunginstitut as Segelflug ) in a team of famous gliding ( Dittmar , Späte , Reitsch ... ), which under the leadership of Alexander Lippisch elaborated the draft of the first fighter rocket engine . Schmidt was killed in 1943 during a test flight of a prototype of the Messerschmitt 163 .

Series model derived prototypes Mü -13 Merlin and Atalanta .
1st place in the contest of the 1936 Rhön
2nd place in the competition of the 1938 Rhön
In 1943, after several attempts, the Mü -13 D3 version was developed with a longer fuselage and triangular section behind the wings, with greater drift.
The first single -seat Mü 13 flew in 1936 as a development of the two -seater Mü 10 Milan. It Has an all moving tailplane and DFS Airbrakes for approach control . The D3 model modified rear fuselage has Increased length  , all which Improved the handling qualities over earlier versions .
The Akaflieg München Mü13 was a single-seat development of the two-seat Akaflieg München Mü10 Milan, designed and built by Tony Troeger and Kurt Schmidt, under the direction of Egon Scheibe, in two versions, a motorglider and a pure sailplane. Two prototypes were built:  'Merlin' and Kurt Schmidt's sailplane was named 'Atalante'.
The Mü13s were constructed with welded steel tube fuselages faired and covered using wooden longerons with fabric and conventional wooden wings with plywood skinning back to the main spar and fabric aft. In the prototypes the trailing edge of the wings were taken up by steel-framed fabric covered flaps and ailerons, all deflectable to improve thermalling and approach control, but later production aircraft had the flaps eliminated, upper surface spoilers fitted for approach control, with the Mü13D-3 gaining increased span wings, a lengthened fuselage and an enlarged fin and rudder. This arrangement from Egon Scheibe became known as the Schüle München - Munich School. The pilot sat just forward of the main-spar with his head flanked by the wing leading-edges, severely restricting sideways vision.
The performance of the Mü13 was regarded as particularly good at an L/D ratio of 28 and the ability to fly at relatively high speeds due to the slender Mü Scheibe aerofoil section. 'Merlin', flown by Hans Wiesehöfer, flew around southern Germany and the Alps on point to point flights, but 'Atalante' achieved fame as the mount of Kurt Schmidt, who at the age of 16 had been responsible for building a large part of 'Atalante as well as piloting the glider at the 1935 Rhön competition at the Wasserkuppe, achieving the longest flight at 252 km  from the Wasserkuppe to Trier. The success of Kurt Schmidt brought attention to the Mü13 and demand for a production version. Among other accolades 'Atalante', piloted by Kurt Schmidt, also set a German goal flight (fly to a specified goal) record of 482 km  in May 1939

With improvements the Mü13 went into production as the Mü13D, built by the Schwarzwald-Flugzeugbau Wilhelm Jehle in Donaueschingen, with Mü13D's taking part in most gliding competitions from 1936 to the start of WWII.

A tandem two seat version was also produced postwar as the Mü13E, which was later developed into the Scheibe Bergfalke series of Trainers.[2]

The 'Merlin' was rebuilt with  an 18 hp (13 kW) Köcher-Kröber M4 two cylinder horizontally opposed engine fitted in the nose, re-designated Mü13M Motormerlin, reaching a top speed of 125 km/h  and landed at 45 km/h  making wheel brakes on the retractable mainwheel superfluous. Taking part in the 1937 Rangsdorf competition the Mü13M Motormerlin scored highly demonstrating the best performance.

Mü13 'Merlin' - First prototype of the Mü-13 built in 1935.
Mü13 'Atalante' - Second prototype of the Mü-13 built in 1936.
Mü13D - Production aircraft built by the Schwarzwald-Flugzeugbau
Mü13D-3 - One of the last variants of the Mü-13 introduced in 1943.
Mü13E - Post-war development flown in 1951 and produced as the Scheibe Bergfalke.
Mü13M Motormerlin - 'Merlin' fitted with a Köcher-Kröber M4 two cylinder engine.