unintentional; not intended / spontaneous and not thought through in advance / not having any structure or organization

Not planed.

present participle of unplan

Third-person singular simple present indicative form of unplan

(transitive) To undo the planning of (something previously planned); to cancel.

plural of rapid unplanned disassembly

(engineering, euphemistic) An explosion or breakup of a vehicle, usually an airplane or a rocket.

The quality of being unplanned.

Without the use of a plan; haphazardly.