DLR staff member Johannes Anton is a seasoned former
Akaflieger from Munich. Initially, the slender figure and unpre-
tentious glasses appear almost unremarkable, but his powerful
voice and clear pronunciation make him appear all the more
self-assured. Anton completed his studies in mechatronics at the
University of Munich a year or so ago and joined the DLR Flight
Facility in Braunschweig. At the summer camp, his former Ida-
flieg classmates know him only as ‘Pünktchen’. There is a tradi-
tion at the summer camps that everyone is given a nickname:
“Mine was from ‘Pünktchen and Anton’, so there we are,” says
the 30-year-old.
At the DLR Flight Facility, he is now focusing on the
collaboration between DLR and Idaflieg. DLR has two gliders,
the DG 300 and the recently acquired Discus-2c. “We have
brought both aircraft to the summer camp. They are used by
the students as measurement aircraft.” The DG 300 has been in
use for almost 30 years and is known by the students as ‘The
Saint’. It is packed very carefully and kept in the hangar – the
wings and fuselage are clothed in protective covers. “The DG
300 must not be scratched,” reveals Anton during an inspection
of the hangar. “This is because we use it as a reference aircraft.”
He pulls one of the covers back and brushes his hand over the
smooth wing. “It’s a bit like the standard metre – the DG 300 is
the most precisely characterised glider in the world in terms of
its flight characteristics, so it is something of a ‘saint’.” He grins.
“We only ever use it for comparison flights early in the morning –
the DG does this by flying with another glider in a shared parcel
of air – only about one wingspan apart.” Afterwards, the young
researchers study the flight performance of the glider being
tested so it can be precisely compared with the DG. “When we
do this, we pay special attention to measuring the polar curves
of new gliders, which compare sink rate with horizontal speed.
This tells us how well a glider sustains flight or, alternatively,
how much it descends in a section of the flight path,” explains
the enthusiastic small aircraft researcher. “We have to carry out
at least three reference flights to measure the gliding properties
of a new model.”
Riding a bicycle on the airfield. This is where one can
find George Mitscher, a test pilot at the DLR Flight Facility. He
is wearing an aviator’s cap and shorts – comfortable clothing
for hot days at the airfield. He immediately welcomes you with
a beaming smile. Normally, Mitscher flies the DLR Do 228-101
research aircraft from the DLR site, but for three weeks in
August he has travelled to Aalen-Elchingen at the controls of
‘Victor Echo’, the four-seat DLR aerotow plane. Here, he is
known as ‘Schorsch’. The 30-year-old fits in well among the
ranks of young flight enthusiasts; he joined DLR two years
after completing a university degree in aerospace engineering.
He learned his aeronautical skills as a glider pilot in the club
before becoming a professional pilot.
“We flew in a dual formation from Braunschweig to the
airfield at Aalen-Elchingen,” Mitscher tells me in a break be-
tween two towing flights. As he does so, a group of Akafliegers
push a glider that has just landed back over the grass to the
take-off point. “We were able to use another aerotow plane
that we have on loan to tow the DG 300 and the Discus-2c over
Germany right next to each other, side by side,” reports the DLR
pilot. “It was good practice for the numerous towing manoeu-
vres I will have to fly here.” He takes a drink from a water bottle.
“The early morning comparison flights are especially nice. We
take off in dual formation, the DG 300 on one tow line, a new
model on the other, and climb up to 3000 metres above the
often mist-covered landscape.”
The DG 300 is still on this ‘saintly’ comparison mission,
but in less than two years, if it has been sufficiently fine-tuned,
the Discus-2c will be climbing into the early morning sky with
the new prototypes to measure their flight performance. The
DG 300 will then be able to have a well-deserved retirement.
After a weather briefing for the rest of the day, Kai
Rohde-Brandenburger from the DLR Institute of Aerodynamics
and Flow Technology reveals that the Discus-2c will be capable
of doing something more: “A comprehensive set of measure-
ment sensors was integrated into the glider when it was built.
For example, we will be able to capture the smallest strains in
the fuselage and wings.”
The 30-year-old is a strong, friendly person, a real ‘guy’s
guy’. Like his colleagues, he is lightly dressed for summer. You
can immediately tell that he is a Braunschweig Akaflieger – on
his T-shirt, 11 white glider silhouettes are arranged in a circle
surround the lettering. He proudly points to it and says: “These
prototypes were developed by the Braunschweig Akaflieg over
the past 90 years.” Underneath it is a silhouette with conspicu-
ously large wings. “That is the SB10 from 1972, the largest gli
der in the world – with a 29-metre wingspan.”
Student aerodynamics clubs have a long history in Germa-
ny, and are almost unique in the world. In 1918, after the First
World War had been lost, aviation research in Germany was for-
bidden under the Treaty of Versailles. “But there was one excep-
tion,” the Braunschweig researcher says. “Aircraft with no en-
gine were not covered by the ban, so student gliding groups
thrived and started a tradition that has been maintained until
today.”
In July this year, Rohde-Brandenburger moved from the
Braunschweig Akaflieg to the DLR Institute of Aerodynamics
and Flow Technology. Alongside Johannes Anton, who is a
member of the DLR Flight Facility, maintaining contact with the
aerodynamics students and supervising the gliders and small
The gliders line up – on peak days, more than 50 young pilots get
together at the Idaflieg summer meeting on the Aalen-Elchingen
airfield.
Discus-2c and DG 300 –
the two DLR gliders
The Discus-2c glider is a brand new member of the DLR
research aircraft fleet. It will be used as the comparison
aircraft of the future, to measure the gliding properties of
new types of glider under development. The DG 300 has
been fulfilling this task for almost 30 years. The new
high-performance glider will answer questions concerning
aeroelasticity. Stress measurement strips and fibre Bragg
sensors are integrated into the wings and fuselage of the
Discus-2c to measure distortion. An integrated enclosure in
the fuselage enables a wide range of scientific applications
for the research aircraft. The pointed mast on the nose
carries a five hole probe for measuring the airspeed and
angle of attack.
Technical data
Discus-2c DLR:
Wingspan: 18 metres
Weight: approx. 290 kilograms
Maximum take-off weight: 565 kilograms
Maximum speed: 280 kilometres/hour
DG 300-17:
Wingspan: 17 metres
Weight: approx. 293 kilograms
Maximum take-off weight: 550 kilograms
Maximum speed: 270 kilometres/hour
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GLIDERS
Dual formation in the early morning: the glass canopy
offers a fantastic panoramic view. Below and left or
centre, the aerotow plane can be seen. The cockpit
canopy reflects the light of the rising Sun. On the right,
the second glider and its aerotow plane are visible.
aircraft, Rohde-Brandenburger looks after scientific projects in
this area. The engineer’s work is focused on the DLR Discus-2c
research glider. With gleaming eyes, he lists the capabilities of
this unique aircraft, while he explains the displays in the cockpit:
“There are acceleration sensors and magnetic field sensors on
board. In the fuselage there is a large enclosure for a wide
range of measurement instruments.”
The researcher is particularly proud of the integrated fibre
Bragg grating: “In this experiment, we send light of various
wavelengths through the structure of the new research glider,
Aerodynamics Student Flying Groups
Braunschweig, Munich and Berlin are just some of the cities
in which academic trainees demonstrate their enthusiasm for
gliding. In ‘Akafliegs’ (Akademische Fliegergruppen, or Aerody-
namics Student Flying Groups), they learn all about this traditional
sport and more – they fly, build and research gliders. Volunteers
play a large part in this. Alumni who are now working in industry
and research support the young aviation enthusiasts. DLR test
pilots have also come from among their ranks. The summer
camp held by Idaflieg (Interessengemeinschaft deutscher akade-
mischer Fliegergruppen; the Amateur Association of German
Groups of Aerodynamics Students) in Swabia is the annual high
point in the lives of the student flight pioneers. This summer,
DLR was there too, with an aerotow plane and two measure-
ment gliders.
Cockpit view of the Discus-2c
Image: TU Braunschweig, Institute of Flight Guidance
