Fasting on 10th Av (Tish’a b’Av deferred) while in Flight

Yom 2, 19-04-65 — 19 Tamuz 5772

Question
Dear Rabbi
I booked tickets a long time ago for a family holiday to the USA. I did not realize that the flight was on “tisha b’av” as it was not marked in my calendar – I assume because this year the fast is put off to the Sunday.
Our flight leaves Israel at 5am Sunday morning for Frankfurt where we have a stop over until 2pm local time before flying on to the USA arriving at around 6:30pm with the fast ending around 8:30pm. I am flying with my wife and four children aged 12, 10, 9 & 8.
I am concerned about what I and my wife should do about fasting given that the air conditioning on the plane will make the fast much harder than usual. Is there any possibility of going according to Israel time to avoid fasting for a day and half?

Response
Shalom Rav
It is most unfortunate that you booked a flight for 10th Av. The fast of Tish’a b’Av is the most tragic day in our long history. It is a day for introspection. On this day we do not just commemorate past events; we examine ‘Am Yisrael’s failure to live up to its mission to establish a nation-state based on the principles and precepts of the Tora, and plan how to rectify this state of affairs. It is most inappropriate to travel on this day. Even engaging in one’s usual work is discouraged (see Rambam’s MT Ta’aniyoth 5:10). If there is any way of rescheduling your departure, I strongly recommend that you do so.
If this is not possible, you and your wife will have to fast. Were it one of the other fast days, you would be exempt. Tish’a b’Av, however, is more serious (see TB Rosh HaShana 18b 12). According to Rambam our forefathers fasted on Tish’a b’Av even when the 2nd Miqdash stood (commentary on the Mishna, Rosh HaShana 1:3). This fast day remains in effect until our national reality is fully righted, i.e. until ‘Am Yisrael lives as a sovereign nation in our Land with a Miqdash, Beth Din Gadhol, etc.
You cannot go by Israel time. One goes by where one is, on land, at sea or in the air.
If you suffer from a medical condition such as diabetes, you can fast till midday and then eat unless instructed otherwise by a doctor. If according to expert medical opinion you may not fast at all, you are exempt. If your wife is expecting, she is not obligated to fast beyond midday. If you feel very ill and near fainting, you may drink water.
There are preparations that one can take before the fast which can make a big difference. I recommend speaking to a doctor or pharmacist.
Kol Tuv
Rabbi David Bar-Hayim