As I understand it, you can't (at least not without some permission from authorities). This matters are mainly covered by
Civil aviation law 143/1988.
You should check §32 (10) to (11).
(10) Povolenie podľa odseku 1 sa nevyžaduje pre iné plochy, ako je letisko, ktoré sa používajú na vzlety a pristátia lietadiel iba dočasne alebo
príležitostne alebo na vzlety a pristátia lietajúcich športových zariadení. Podmienky na používanie týchto plôch určí Dopravný úrad.
(I dare not to translate it as this is really a law stuff)...
But here is the internet site of
Transport authority – Division of civil aviation and I bet they can answer your question directly because in that mentioned § it says that they are in charge of determining and using lands which are not an airfield.
Assitant of director is Eva Oravcová e-mail
[email protected] +421/2/48 777 501.
Good luck.