Pilgrims traveling by airplane to Makkah for Hajj or Umrah must enter ihram before their flight crosses the miqat boundary established by the Prophet (peace be upon him). Since modern aircraft travel at high speed and cross the miqat in seconds, scholars unanimously advise preparing in advance. Sheikh Ibn Baz and Sheikh Ibn Uthaymeen both ruled that the pilgrim should wear ihram garments either at home, at the departure airport, or on the plane before reaching the miqat, and then make the intention (niyyah) and pronounce the talbiyah when the plane is about to cross or is crossing the miqat line.
Many airlines flying to Jeddah announce when the aircraft is approaching the miqat, and pilgrims should be ready at that point. As a precaution, Ibn Baz recommended making the intention slightly before the miqat if the exact point is uncertain, because entering ihram before the miqat is permissible (though not ideal), while passing it without ihram is prohibited. If a pilgrim passes the miqat without entering ihram, the majority of scholars hold that they must either return to the miqat to assume ihram or, if they cannot return, they must offer a dam (sacrifice of a sheep) as a penalty.
The Permanent Committee for Scholarly Research and Ifta issued a fatwa confirming that the miqat rulings apply equally to those traveling by land, sea, or air, and that there is no exemption for air travelers. Wearing the ihram garments before boarding is permissible and does not constitute entering ihram — the state of ihram begins only with the intention and talbiyah.