VGC News/Newsletters - Lakes Gliding Club

Features
KRANICH 2 (JERAB 2)
(This is the article that should have accompanied the two
sheets of Kranich drawings that appeared in our VGC News
No.94 on pages 26 and 27. Unfortunately, it was not possible
at that time to get it translated from Czech into English. This
abridged translation was made possible by Lubomir Hodan at
Zbraslavice during last years International Rendez-Vous
WHEN CRANES FLEW by Jan Brskovsky and Petr
Antos. Members of the Aviation Historic group.)
In the second half of the 1930s, there was an increase in the
organizational and technical level of gliding, which was the
basis for today's gliding. The main gliding centres received
news of records some of which (if not most) were flown by
German pilots. In Germany, gliding enthusiasts were sponsored
by the state and this led to the increase in strength of the
Luftwaffe, which prepared it for the coming World War. Main
centres were at the Wasserkuppe and Grunau, which is ilow
Jesow Zeleski in Poland. DFS at Darmstadt very Inuch
assisted the growth of the gliding Movement It had an excellent
Met. specialist in Professor Doctor Waiter GeorgH and the
Chief Designer waS Hans Jacobs. From 1932 on, his name was
connected with the foremost designs. One of them was the
single seater Rhonsperber in 1935 and, during the next year,
the 2-seater Kranicb, which w.as developed from the
Rhonsperber. The main advantages of the Krankh were an
exceUent thermalling ,capabi'1ity with the ability to be used for
instruction and blind flying training, and for improving flying
technique. Elementary glider pilot training at this time was
with single seat Primaries. In Germany. there were the
ZOglings and the later sa 38s. In Czec'hoslovalda, there was
the very popular "Skaut". Two seaters were onfy used for
advanced training. For this, the Kranich was very good.
During wartime and after the war, ,the type was more and more
used for elementary training. During the 19.30s, the Kranich's
pelformance put it among the best g,liders in the 2-seater class.
In Soviet Russia, the best 2-seater was the "Stakhanoviets" but
this glider was not produced in quantity. Only during wartime,.
was there a mot~ve to develop the 2-seater for pre-military
training, and for the elementary training of troop carrying
glider pilots. For example, we must look to the USA where
Schweizer. Laister Kaufman and Pratt Read two seaters were
designed to meet the need for training troop carrying glider
pilots. This wartime experience led by the back door to the
postwar training of glider pilots in high performance two
seaters. But the first place taken by the Kranich in postwar
European sport gliding can not be denied. In Czechoslovakia,
a two seater was designed by Anton Kralovice and called
KSM I. Postwar. this was the K-7 which was named Udarnik.
However the Kranich 2 or Jerab was mainly used until the
Czech designed LF-l09 Pionier and LO 130 Kmotr came into
production. These brought forth the question as to whether it
was better to have tandem seated or side by side two seaters
for training. The famous German glider pilot and designer
Wolf Hirth developed the Oovier with side by side seating.
The Schempp Hirth firm started to mass produce it, and later
in 1948, the Dutch firm Fokker built 6 examples. The Govier
was someth.ing of an example for our Kmotr, but the number
built did not compete with the number of Jerabs built even if
the visibility for the instructor was many times better than that
from the Kranich.
The PROTOTYPE. The Kranich was designed in 1935 and
its first test flight was carried out by the experienced German
test pilot Hanna Reitsch. She was personally involved with the
prototype's, development, and it was written in an Aviation
publication that it had 2 months testing during which it was
flown for about 90 hours. At the time of its testing by DFS, its
designer Hans Jacobs and Herbert LUck prepared its documentation
for series production. The prototype flew with open
canopies but, very SOOI1, its designers prepared its characteristic
plexiglass canopy. This was mainly built from a metal
tubular frame which was at first covered with celluloid, but
later with organic plexiglass (perspex). Its flyillg tests generated
great enthusiasm for its development except that the rear
cockpit, which is placed between main and rear wing spars did
not offer good visibility forwards and downwards. In the wing
root on both sides near the rear cockpit, were built-in transparent
windows, which offered a limited possibility for the
instructor to observe the situation, and the countryside below.
FIRST PRODUCTION SERIES. The large, strongly built
but good machine with gulled wings was put into production
by the firm of Karl Schweyer at Darmstadt, and later ,in
Mannheim. This became Jacobs Schweyer. Data from the
period concerning production in Germany between 1939 and
1941, suggests that about 150 Kranichs were built.
ENTREE. The first time that the Kranich 2 became famous
was during the 1937 National Rhon Contest. The first version
had small differences between it and the production Kranich
I. For example, the Kranich I had an aerodynamically balanced
elevator and a servo trim tab on the ailerons' trailing
edge etc. During the next year at the 1938 (the 19th) Rhon
Contest, 6 out of the 8 crews entered for the two seater category
B were using Kranichs. In 1939, 18 crews took part
flying Kranichs representing the Nazi NSFK and the Luftwaffe.
This was characteristic for this time as Kranichs were
being used for military training and for instruction. The time
was just before World War 2, as the contest was held during
July/August 1939. The performance potential of the Kranich
was so good that it was good propaganda material for the 3rd
Reich in other countries. On 12th April 1937 pilots Beck and
Knier had flown a distance of 193 kms.from the Hornberg to
Bingen and on the 3rd of May 1939, the pilots Spilger and
achieved a gain of height of 2,276 m. On the 3rd of August
1937, Ziller and Quadfasel got higher, to 3,304 m.in a snow
cloud and temperature as· low as -40 degrees C. Ziller ltew to
over 8,600 m on the 28th November 1938 over Grunau. There
was also BOclekker and Zander's World duration record in a
Kranich 2 of 50 hours 15 mins from the 9th -11 th December
1938. Not recognised as a World record was the 1938 Rhon
contest climb to 8,000 m. by Romeis and Schillinger (the
Kranich broke up but they both were saved by their parachutes.CW).
Also not recognised officially was the climb of
Eric KlOckner to 9,200 m. in wave over ZeU am See on the 15
May 1939. later he increased this to HAlO m on the 11th
October 1940. Erich Kloekner realized both these performances
in the Special Kranicn 0-11-4002 which had been
designed for cloud flying and flying in ,the Alps. This was
known as the Cloud Flying or Wolken (W) l'