PIK-20D Fatigue Evaluation

Trafin tutkimuksia 7-2015

Erkki Soinne

European Aviation Safety Agency EASA has requested Trafi to establish
a special inspection program for PIK-20 series aircraft. This
report explains the reasoning for the inspection interval and the
inspection objects. As a basis for this the stress calculations, fatigue
and material tests and drawings of PIK-20D were reviewed. A
noticeable effort was made to find and collect all relevant material
data established in the 1970s. Also relevant MSc thesis documents
were collected and reviewed as appropriate. Contradictory results
in fatigue calculations were checked and the results were transformed
to be consistent with the Kossira-Reinke spectrum (including
aerobatics) which has become a standard in Europe. At present
the report contains the most complete overview on PIK-20D fatigue
and shows that there are no known fatigue problems.