Is turning toward the Qibla obligatory when praying on a conveyance due to illness or rain?

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Turning toward the Qibla remains obligatory when praying on a conveyance due to illness or rain. This is the apparent view of Al-Khiraqi, who stated that in these two situations, neither obligatory nor supererogatory prayers may be performed except while facing the Kaaba. The evidence is the generality of the verse, "And wherever you go forth [in prayer], turn your face toward the Sacred Mosque," (Quran 2:144). The exception is made for the state of fear in obligatory prayer to preserve life, but in all other circumstances, facing the Qibla remains binding based on the general nature of the verse.