There could be many reasons:

1. To convince her, and you, and those she shares such information in advance with that He is in control in this turbulent world and still speaks prophetically to His people;
2. Because this is a prophetic sign of something else shortly to come to pass that will require even greater faith (on her part, and others') than that exercised in the first vision with its three spread out events;
3. The three events are a hint (remez) at something else happening, or about to happen, involving the nations involved in the air crashes.

Thank you for sharing.

Thank you for your insights. God bless you.