take a look at astridsolcer.nl/ the indexpage. 
below the picture of south africa we see a green bar then white space and then an airplane.
On devices like: desktop, smartphone (portrait and landscape) and ipad (landscape) the airplane is directly against the green bar. I changed in astroid under layout within the section of the airplane some values.
But the white space above the airplane  is staying when i look with ipad on portrait.
Can you tell me how i can get rid of this white space.
I allready changed values within margin for tablet and small. But there is no change for the tablet in portrait view

This has nothing to do with the iPad, but rather with the standard dimensions for the media screen. You need to remove the 5% from the top and bottom in that section. Apparently, you haven't done this for all display sizes. Always go through all display sizes when editing padding and margin.

just checked it out but i can not see where i 5% used within margin or padding. there are values but they are working nice for the devices except for tablet on portrait.

you must take margin-bottom -10% in the section.