Nishasti narm, chunin nishasti apparati parishi kayhoniro menomand, ki dar vaqti on surati apparat dar lahzai rasish ba sathi saiyora va yo digar jirmhoi osmoni kamtarin (dar holati ideali — sifr) ast. Nishasti narm boyad butunii konstruksiyayu sistemahoi apparat va imkonpazirii kori minbadai onro tamin namoyad. Dar sayyorahoi atmosferador Nishastii narmmi apparathoi parishro bo rohi nishastan chun samolyot yo bo rohi istifodai sistemahoi parashyuti tamin kardan mumkin ast. Nishasti narmi apparathoi parish ba jirmhoi osmonii beatmosfera bo rohi ba vositai muharriki tormozii raketa yo tajhizoti makhsusi amortizatsioni purra qat kardani surati furud ba dast ovarda meshavad.