I live in Israel but am flying to France on Isrug Chag Simchat Torah which is also Erev Shabbat (10/17/14). R’ Halberstadt shlit"a says I should not enter the tchum of a Jewish yishuv until after the time it would take to arrive following Yom Tov Sheini. My questions: - What is "Jewish yishuv" here -- my family in France? The shul? - If I can be with my family, can I do malachot osurot to them b’farchesia? - Is this a special case in which I could enter the yishuv earlier, since the Yom Tov Sheini goes directly into Shabbat?

Any city with Jewish residents is considered a "Jewish Yishuv" (a city populated with Jews) even if the Jews are few. This is in regard that a "Ben Eretz Yisrael" (a permanent resident of Israel) should not perform any prohibited activities publicly on "Yom Tov Sheni Shel Galuyot - the second festival day in the Diaspora" (Igrot Moshe Yoreh De'ah vol. 4, 24, 2). According to Rav Shlomo Zalman Auerbach ZT"L it is permitted for a "Ben Eretz Yisrael" to land in an airport on "Yom Tov Sheni" even if the airport is within a city populated with Jews. Others are stringent in this regard. Nevertheless, all agree that one should not enter the city itself until Motzaei Yom Tov Sheni. (Yom Tov Sheni K'hilchato 3, 11, page 136). According to this, you are theoretically allowed to fly to France on Isru Chag (the day following each of the three feasts: Passover, Shavuot, Sukkot) and stay at the airport until the end of Shabbat, but because it is not probable that you would like to do so, and there are obviously many other issues staying at the airport for the entire Shabbat, the only option is to postpone the flight until Motzaei Shabbat (Saturday night). In a regular year where the second day of Yom Tov does not fall out on Friday, it is permitted to depart Israel on Isru Chag, arrive at the airport in France during "Yom Tov Sheni Shel Galuyot" and exit the airport after the holiday ends.