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to gliding. These rapid response rate of climb instruments were known in lighter-than-air craft but had not been used on gliders. The two came together to produce a glider, designed by
Lippisch and built at the RRG that had the performance to utilize thermal lift detected by the variometer. The
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Plans for the
Professor were widely sold to commercial manufacturers and to clubs both in Germany and abroad, though the total number of Professors built, sometimes with small variations, is not known. One at least, constructed in Germany, came to the UK and was flown by
109:, previously assumed to be too weak to assist gliders. He directed flights of a light, powered aircraft which, with its engine idling, discovered uplifts of several metres per second. At about the same time Alexander Lippisch, who had earlier worked at
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the wing was ply skinned, forming a torsion box; behind the spar the wing was fabric covered. Its rectangular centre section occupied about one third of the overall span and was braced to the lower fuselage on each side with a
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who found a thermal under a cloud, flew to mountains and slope soared, then returned against the wind to the
Wasserkuppe, aided by more thermals en route. Almost immediately other pilots began to find lift under clouds.
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with a straight, sloping edge but rounded top and heel. The rudder projected below the fuselage but was protected on landing by a small tail skid. The tail surfaces were all fabric covered behind the ply leading edges.
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with fuller, curved ailerons, modifications first applied to the prototype Rhöngeist. The
Professor II also had new horizontal tail with a fixed, swept tailplane mounting constant chord, rounded tip
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result was the RRG Professor, first flown in May 1928 and intended by RRG to be built in numbers by clubs under licence, from their plans. The prototype was christened the Rhöngeist (English:
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After its first flight on the
Wasserkuppe in May 1928, the Rhöngeist joined the annual national competition there and made its mark with a flight on 6 August 1928, flown by
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immediately ahead of the pedestal and equipped with the variometer. A rubber sprung skid on the underside reached from the nose to below the trailing edge. It had an
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s. Like other high performance gliders of it day, it was slow to come out of turns and with its strongly tapered wing, prone to
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The
Professor's hexagonal, ply covered, deep flat sided fuselage tapered strongly aft. The pilot sat in an open, unscreened
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was a very early soaring glider and the first to use a variometer for finding thermals. It was designed by
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larger area ailerons with curved trailing edges and a tailplane with conventional elevators. Flown 1929.
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in
Germany, first flying in 1928. The Professor was widely built by both flying clubs and factories.
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383:(2nd revised ed.). Königswinter: EQIP Werbung & Verlag GmbH. pp. 58–61.
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of each outer section was filled with a straight edged, slightly tapered
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on a tall ply skinned, streamlined pedestal and built around a single
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This was an all wood-framed aircraft, covered in a mixture of
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RRG Professor 3-view drawing from L'Aerophile March 1931
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101:, an academic meteorologist and head of the
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213:. Two were built in the United States as
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348:13.2 kg/m (2.7 lb/sq ft)
117:was considering the application of the
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7:
297:16.10 m (52 ft 10 in)
233:with a cut-out for rudder movement.
152:. From the spar forward around the
291:7.00 m (23 ft 0 in)
14:
303:18.6 m (200 sq ft)
469:Djävlar Anamma (Hols der Teufel)
245:the original design. Flown 1928.
16:German single-seat glider, 1928
1:
590:Delta IV (DFS 39/Fieseler F3)
753:Aircraft first flown in 1928
103:Rhön-Rossitten Gesellschaft
55:Rhön-Rossitten Gesellschaft
774:
333:246 kg (542 lb)
327:166 kg (366 lb)
123:
21:
105:(RRG), began studies of
97:In early 1928 Professor
743:1920s German sailplanes
379:Simons, Martin (2006).
276:General characteristics
614:Ground effect vehicles
559:Jacobs Hols der Teufel
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93:Design and development
408:Göttingen 549 airfoil
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381:Sailplanes 1920-1945
271:Sailplanes 1920-1945
186:all-moving tailplane
169:of 1:3. The whole
758:High-wing aircraft
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87:Alexander Lippisch
66:Alexander Lippisch
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595:Delta V (DFS 40)
573:Powered aircraft
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133:gliding centre.
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35:Type of aircraft
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42:National origin
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124:Ghost of the
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72:First flight
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308:Aspect ratio
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248:Professor II
223:Professor II
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219:tip stalling
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211:Philip Wills
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154:leading edge
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82:
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509:Storch VIII
339:Performance
215:Heller Hawk
167:taper ratio
131:Wasserkuppe
737:Categories
499:Storch III
484:GrĂĽne Post
355:References
301:Wing area:
163:lift strut
119:variometer
22:Professor
631:RFB X-114
626:RFB X-113
534:Professor
524:Delta III
504:Storch IV
494:Storch II
295:Wingspan:
269:Data from
242:Professor
231:elevators
115:Zeppelins
75:May 1928
62:Designer
667:P.01-118
662:P.01-117
657:P.01-116
652:P.01-115
647:P.01-111
640:Projects
585:Delta IM
580:Storch V
554:Fafnir 2
519:Delta II
489:Storch I
479:PrĂĽfling
446:aircraft
444:Lippisch
237:Variants
146:fuselage
107:thermals
46:Germany
30:Soaring
600:DFS 194
514:Delta I
474:Zögling
452:Gliders
317:Airfoil
289:Length:
221:. The
182:cockpit
175:aileron
161:V-form
138:plywood
111:Dornier
605:Me 163
549:Fafnir
387:
194:rudder
159:faired
142:fabric
57:(RRG)
32:glider
712:P.13b
707:P.13a
529:Falke
283:Crew:
227:chord
27:Role
722:P.20
717:P.15
702:P.13
697:P.12
687:P.10
682:P.09
677:P.08
672:P.04
564:DM-1
539:Wien
385:ISBN
150:spar
140:and
81:The
544:Obs
285:One
190:fin
113:on
739::
363:^
312:14
177:.
436:e
429:t
422:v
393:.
319::
310::
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