Civil Engineering Reference
In-Depth Information
Table 14.1
Load approach
for Starfighter F 104
Starfighter F 104
1
Mass
13 t
2
Impact speed
102 m/s (
¼
mach 0.3)
3
Max. impact force
17 MN
4
Impact period
120 ms
5
Time response
Half sine
2.1 m
2
6
Impact area
14.3 Load Approach for Fast Flying Military Aircraft
14.3.1 Load Approach for Starfighter
Due to the number of observed crashes of military aircraft of the model Starfighter
load functions were first derived at the end of the 1960s and the beginning of the
1970s. After the examinations had been carried out under the assumption of a fully
plastic impact the load approach detailed in Table
14.1
was established. For the
design of the structures a static load of 17 MN was used as a substitute for the
maximum impact force. The assumed impact area was 2.1 m
2
. Using this procedure
a minimal protection was to be ensure for similar effects.
14.3.2 Load Approach for Phantom
In the further development an intensive investigation of the danger of an accidental
airplane crash was conducted in the beginning of the 1970s. A representative load
approach was to be defined for the design that covered all relevant aircraft types.
Starting with the Riera-Model of a deformable projectile Drittler, Gruner, and
S¨ tterlin continued the development of a mathematical model in 1973 and
suggested an impact load-time function for the accidental crash of a Phantom
onto a rigid concrete wall. This load function is shown in Fig.
14.5
and corresponds
to the function later adopted in the RSK-Guidelines in 1981. It was used for the
design of all new nuclear power plants in Germany.
In the years after, i.e. the end of the 1970s and the beginning of the 1980s,
numerous additional studies were conducted regarding the impact problem of
deformable and rigid projectiles on rigid and deformable targets. The effects of
wreckage and debris were given special consideration. Aside from the theoretical
development extensive experiments were simultaneously carried out in different
scales to verify the mathematical models. Especially worthy of mention are the
so-called Meppen experiments (cf. [
6
]). Ballistic tests where deformable steel pipes
were shot at thick reinforced concrete slabs were carried out on the exercise area of
the German armed forces in Meppen within the frame of a research project
supported by the German Federal Ministry of Research and Technology and with
