Reference: Fataawa al-Lajnah ad-Daa.imah lil-Buhooth al-‘Ilmiyyah wal-Iftaa. – Volume 11, Page 10, Fatwa No.4624
Fataawa al-Hajj wal-‘Umrah waz-Ziyaarah – Page 35
Question: A man wanted to perform the Hajj or ‘Umrah and put on the ihraam clothing on the airplane. Then he did not know the place of the meeqaat, so should he delay entering the state of ihraam once he reaches Jeddah or not?
Response: If he intended the Hajj or ‘Umrah [whilst arriving] by air, then he should take a bath in his home and wear the izaar and ridaa (ihraam clothing), if he wishes. So if there is only a little time before approaching the meeqaat, he should enter the state of ihraam according to what he intends, whether the Hajj or the ‘Umrah, so there is no difficulty in this. And if he does not know about the meeqaat, then he should ask the pilot of the airplane, one of the hostesses or one of the passengers whom he trusts and who has some experience in this.
And with Allaah lies all success and may Allaah send prayers and salutations upon our Prophet ﷺ and his family and his companions.