Mo. Rev. Stat. § 305.080

Any aeronaut or passenger who, while in flight over a thickly inhabited area or over a public gathering within this state, shall engage in trick or acrobatic flying, or in any acrobatic feat, or shall, except while in landing or taking off, fly at such low level as to endanger the persons on the surface beneath, or drop any object except water or loose sand ballast, shall be deemed guilty of a misdemeanor.