Reference: Sharh ‘Umdatil-Fiqh – Tape No.9, Question No.36
Question: How should the obligatory prayer be performed in an airplane, bearing in mind at the time of prayer it [could] turn in its direction?
Response: This is according to what he is able to do, [as Allaah (‘Azza wa Jall) says]:
{So fear Allah as much as you are able}, soorah at-Taghaabun, aayah 16
…[so] he should pray according to [the best of] what he is able.
