I don't understand anything
I try gain and count not fond the situation as described before
Now climbing speed 140 kts  and 1000 ft/min.
I try different situations between trim and pitch without better performance.
The attached picture shows horizontal fligh at FL130 but not more 180 kts at full power.
If I trim horizontally the Airplain descent with 3000 ft/min.
There are any problems but I have no Idea.
I is strange that Markoz found onetimes my first bad situation and some times later the better one.
Now I can confirm this performance change from one day to another. But only for this Type LC-130

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