D-B1 "Stehaufchen" = F.V.D. "Stehaufchen"
Type
Single seat glider
Engine
 
Dimensions
Length 4,80 m, height 2,00 m, upper windpan 8,00 m, lower wingspan 6,00 m, wing area 18,7 m2
Weights
Empty 70 kg, flying weight 140 kg, wing loading 7,5 kg/m2
Performance
max. glide ratio 1:8
Type
Werk.Nr
Registration
History
     
First flight 23/8 1921. Took part in the Rhön competition 1921, 1922. Crashed just before the 1923 Rhön
Before the formal formation of the Akaflieg Dresden in about 1924, there was collaboration between the Technical High School Dresden (TH Dresden) and the local flying club, the Flugtechnischer Verein Dresden (F.V.D.). The Stehaufchen was one result, named and designed by three TH Dresden students, Horst Muttray, Reinhold Seiferth and Rudolf Spies. The biplane configuration was chosen to ensure strength against rough handling and its small size by the need to fit within the 4.20 m  limit set by rail transport. Construction began on 11 June 1921 and the first flight took place only about ten weeks later on 23 August on the Wasserkuppe.
During its career, the glider was known in England at least as the F.V.D. Stehaufchen after the club, or just as the F.V.D. glider to distinguish it from the F.V.D. monoplane or Doris of 1922. After the founding of the Akaflieg Dresden it was retrospectively renamed the D-B1 Stehaufchen, numbering it as the first of their ten designs.

The Stehaufchen was a single bay biplane with two spar wings of unequal span mounted without stagger but with an unusually large interplane gap of 1.50 m . The lower wing was mounted on the lower fuselage and the upper one held high above it by three pairs of inverted V-struts, one pair leaning backwards from the nose to the forward spar and the two other running vertically from the upper fuselage longerons to the two spars on the centre line. On each side a pair of parallel, slightly outward leaning interplane struts connected the forward and rear spars from the lower tips and the bays were cross braced with wires. Both wings were roughly rectangular in plan and slightly swept (1.2°); only the lower one carried dihedral (2°). The ratio of upper to lower wing areas was about 1.6:1. The wings, like the rest of the aircraft had a wooden structure: the spars were both wooden boxes and the leading edges were double ply skinned. Elsewhere the wings were fabric covered. Roll control was by wing warping on both planes.

The glider had a simple, wide, rectangular cross section fuselage with four cross braced longerons forming trusses. It was skinned with two-ply, with a final fabric covering. From the side the nose was smoothly rounded into a single curvature form with the open cockpit behind it, placing the pilot's seat close to quarter chord. Aft the depth decreased and the tailplane was attached to the top with the fuselage ending at the coincident elevator and rudder hinges. The horizontal tail surfaces were roughly rectangular and the elevator was a single piece structure. The fin was a quadrant and the rudder almost semicircular but cut away below for elevator movement. All the tail surfaces were wood framed and fabric covered. The Stehaufchen's undercarriage was a parallel pair of skids, intended to protect the low set lower wing on take-off and landings. The unusually broad fuselage enabled the skids to be separated by 700 mm . These were ash, laminated and of double curvature attached at three points, one below the pilot's feet and the others below each wing spar. The final section behind the rear mounting point curved down a little to protect the tail.

The Stehaufchen first flew at the 1921 Rhön contest, the second of the series. Muttray began with a flight on 23 August which lasted just 38 seconds but five days later flew it for three minutes. More than one third of the competing aircraft were biplanes but of these the Stehaufchen was the most successful and its three designers received a 1,500 Mark prize. After the competition the Stehaufchen stayed on the Wasserkuppe until September, making flights of up to 4.5 minutes and enabling Seifert and Spies to get their pilot's certificates.

The Stehaufchen was damaged on the rail journey home and during the rebuild the upper wing was increased in span from 8 m (26 ft 3 in) to 9 m (29 ft 6 in). It resumed test flying in the spring of 1922, launched by bungee cord. In this period several more pilots gained flight experience and their certificates. It then went to the third Rhön contest, where it gained first prize for total time in the air (1851 seconds) and second prize for distance covered in a single flight (2.7 km ).

It went once more to the Wasserkuppe in 1923 but did not take part in the contest; during a practice flight, it crashed and was destroyed.
H. Muttray, R. Seiferth and R. Spiess have designed the Dresden Schooling Biplane Glider  which was built in two months by the Fluchtechnischer Verein, Dresden. The upper wing surfaces are carried straight through, being fastened divisible to a canopy. The lower wing surface is attached to the sides of the fuselage, is V-shaped, staggered slightly to the rear, 25 cm. (10 in.) above the ground next to the fuselage and 40 cm. (16 in.) at the wing ends,
and has a slightly larger starting angle than the upper wing surface.
Each wing surface has two box frames 4 cm. (1.6 in.) wide and 6 to 9 cm. (2.4 to 3.5 in.) high, and the side walls arc sparred. Two layers of veneer wood glued together cover the front edge of the wings in order to obtain a good edge to the air. The canopy struts are glued two-fold, drop-shaped, hollow and wrapped with linen. The square fuselage has a maximum diameter of 70 by 70 cm. (27.5 by 27.5 in.), is drop-shaped in longitudinal direction with an upward curve in the rear to protect the control works and terminating in a horizontal plane; it is covered with fabric. The altitude and side runners are built as one piece detachable from the fuselage and operated with ropes.
The chassis consists of two skid beams consisting of several layers of glued ash wood and tied to the fuselage transversally by means of two bows of ash wood; additional elasticity is secured by adding rubber blocks. This biplane has proven exceptionally suitable for schooling purposes and would be adaptable to a group of sport flyers who plan to establish a summer camp in a suitable country site for the dual purpose of seeking recreation and learning to glide. The original Dresden 1921 glider made several hundred flights without serious damages,some of the flights covering 10 minutes of time and nearly two miles of distance.
Flying Magazine jul 1928