If there's anything "nice" about Ebola, it's that the virus only transmittable from person to person when the infected person is showing symptoms. That makes it much easier to contain, and helps give us all a clue of who we need to stay away from. So even if someone on your airplane starts to show Ebola symptoms the day after your flight, there's no way that you could have gotten sick from them. In fact, even if they had symptoms on your flight, just being in proximity to them is not enough to get you Ebola. You've got to swap bodily fluids in some way – blood, vomit, diarrhea, semen (sweat, saliva and tears can also contain the virus, but at low levels compared to these other fluids [source: Poon]).
How about from people who have had Ebola – can you get sick from them? If they succumbed to the disease and you have direct contact with their bodily fluids even after they've died, yes. If they survived the disease, you are safe. That said, men who have been cured can still carry the virus in their semen for up to seven weeks post-recovery [source: World Science Festival].