Pilgrims traveling by airplane to Mekkah for Haji or Umrah must enter ihram before their flight crosses the miqat boundary established by Nabi (shallallahu alaihi wa sallam). 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 jamaah haji 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 jamaah haji should be ready at that point. As a precaution, Ibn Baz sunnah making the intention slightly before the miqat if the exact point is uncertain, because entering ihram before the miqat is boleh (though not ideal), while passing it without ihram is prohibited. If a jamaah haji 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 boleh and does not constitute entering ihram — the state of ihram begins only with the intention and talbiyah.