Jane's All The World Aircraft 1913

GRADE. Hans Grade Fliegerwerke, Bork, Post Bruck (Mark). Founded 1910 by H. Grade, who was the first man in Germany to fly with a German machine. During 1911 Grades had a considerable vogue, but since then have not been prominent.

[Illustration: Photograph, from above rear, caption: 1912 racer.]

Model and date. Racer, 1911. Racer, 1912. Racer, 1912.
   C. D. E.

Length..............feet(m.) 33 (10) 21 (6.50) 26? (8)
Span................feet(m.) 39? (12) 34? (10.50) 41 (12.50)
Area .........sq. feet(m^[2].) 480 (45) 240 (22) 360 (33)
Weight, machine...
   ...............lbs.(kgs.) 375 (170) 408 (185) 595 (270)
Weight, useful...
   ...............lbs.(kgs.) ... ... ...
Motor...................h.p. various ... ...
Speed............m.p.h.(km.) 56 (90) 71 (115) 71 (115)
Number built during 1912.... ? 1 or 2 ?

J.Herris German Aircraft of Minor Manufacturers in WW1. Vol I (A Centennial Perspective on Great War Airplanes 49)

Grade

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   Grade's next aircraft was a monoplane. It performed well and Grade kept it in his school and only altered it to meet his customer's demands. He also had a side by side trainer version. The Grade monoplane was a high-wing, single-seater with tricycle wheel undercarriage. The fuselage was comprised of a frame of oval tube with bamboo longerons supporting the tailplane. The pilot's position was a linen-covered tube framework that was suspended on wires and springs.
   The wings were constructed around three bamboo spars, one of which formed the leading edge. The angle of incidence changed along the wingspan and was negative at the wingtips. The wings were fabric covered on both sides but only for approximately 75% of the chord of the bottom wing. Control was by warping the wings. Power was provided by a Grade two-stroke V-4 driving a two-bladed propeller. By 1911 the Grade monoplane was obsolescent.

M.Dusing German Aviation Industry in WWI. Volume 1 (A Centennial Perspective on Great War Airplanes 84)

Automobil- und Aviatik AG, Subsidiary Bork i. Mark

  The Bork branch of Automobil- und Aviatik AG has a differentiated history, having evolved from the “Hans Grade Flieger-Werke”.

Hans-Grade-Werke, Bork i. Mark

Aircraft Development:

  Hans Grade developed a new monoplane from the “Libelle”, the “Schwalbe” in the basic models A, B and C, which differed in their wingspans of 8, 8.5 and 12 meters. The C basic type was designed as a two-seater. Grade also offered a total of seven different engines. This large number of possible combinations was intended to help meet special customer requirements.
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Журнал Flight

Flight, October 2, 1909

Herr Grade Has a Fall.

   WHILE making an attempt to win the Lanz Prize of L2,000 at the Mars flying ground, near Berlin, Herr Grade had a nasty accident with his monoplane, but fortunately without injury to himself. The regulations stipulated that a flight of 2 1/2 kiloms. should be made in a figure of eight. Herr Grade started off splendidly, but in the middle of the trip the propeller broke and the machine fell about 30 metres, but the force of the fall was broken by some low pine trees. The machine was badly damaged, but it was hoped that it would be repaired in a few days.


Flight, November 6, 1909

Herr Grade Wins a Prize.

   AFTER long and patient experimenting, Herr Grade has at last met with success, and last Saturday succeeded in winning the Lanz Prize of L2,000, easily fulfilling the conditions required. These were that the aviator must be of German nationality and use a German built machine, and describe a figure " 8" round two posts placed a kilometre apart. Herr Grade's machine, as will be seen from our photograph, appears like a combination of the latest Bleriot and Antoinette machines, the aviator sitting below the main planes. On the following day Herr Grade had his monoplane out again at Johannistal and made four flights, the first three of 3 mins. 45 secs, 14 mins. 30 secs., and 4 mins. 55 secs, respectively, while the last was of one turn round the course. From this it would seem that at last Herr Grade had overcome his difficulties and evolved a successful machine.


Flight, December 11, 1909

THE GRADE MONOPLANE.

   ALTHOUGH in Germany attention has been almost entirely directed to the development of dirigibles, yet the past year has produced one machine with which some very good results have been obtained. It is the invention of Herr Grade, an engineer of Berlin, who has been patiently working away at the problem for some considerable time. His first machine was a triplane, but as a result of his experiments, Herr Grade gradually modified his designs until the successful flyer was evolved in the form of a monoplane, which in silhouette combines several features of the Bleriot and Antoinette machines. Our readers will remember that Herr Grade's first success was obtained during the last few days of last year, when he was able to rise in his machine to an altitude of one metre and cover distances varying between 100 and 400 metres. After that followed a long period of patient experimenting with but little visible result, and it was not until the early part of last September that Herr Grade came prominently into public notice again. He transferred his monoplane to the Mars flying ground, to the south-west of Berlin, and made three short flights, each of a mile and a half in length. Then success followed rapidly, and Herr Grade has gradually improved his record until on November 15th he remained aloft for 54 minutes, during which he occasionally rose as high as 100 metres. One of his most notable performances was the winning of the Lanz prize of L2,000 for the first German-built aeroplane to describe a figure "8" round two posts placed a kilometer apart. This Herr Grade successfully accomplished on October 30th. Although he has had one or two tumbles Herr Grade has only experienced one serious accident, and that was due to the propeller breaking when the machine was flying at a height of 30 metres.
   With regard to the machine itself, of which we are enabled to give scale drawings this week, it will be noticed that the planes are mounted on a framework built up of steel tubing and carried on three wheels, which are fitted with pneumatic tyres. This framework is remarkably simple, consisting as it does of the triangular front frame and the tube which forms the backbone of the apparatus. This latter member, as can be seen in the plan, is attached to the front frame by a forked end, and this fork carries the main-planes, and is also continued forward to serve as engine bearers. The main planes are strengthened by wire stays, of which those on the upper side meet at the apex of the vertical front-frame, while those on the under-side are attached to the hub-caps, on the Santos-Dumont method. Our photograph clearly shows the way in which the pilot sits below the main planes in a hammock seat suspended by springs from the framework. He controls the machine by warping the wings, by means of the hand lever, and by the tail, which is similar to that adopted by M. Santos Dumont on his little "Demoiselle." The flyer has an area of 208 square feet, and is fitted with a 4-cyl. air-cooled "V" motor, which is also the production of Herr Grade. This is of 24-h.p. and weighs 35 kilogs. The propeller is a two-bladed metal one, directly attached to the crank-shaft. A keel is fitted above the main plane and is continued behind the pilot's seat. That part of it on top of the machine is of inverted "V" section, as it follows the shape of the top portion of the front frame. Incidentally, therefore, it affords a covering for the pilot.


Flight, December 28, 1912.

SOME GERMAN MACHINES.
By G. B.

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   The photograph of one of the latest military type Grade monoplanes shows that the design, in its general lines, has been very little altered from the original machine, what changes there have been being mainly in the nature of detail improvements.
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