What is the schedule of the Yichang to Fengjie hydrofoil?

Yes, you have time to visit the Shennong Stream and Three Little Gorges on the way, but I am afraid that the cruise to reach Fengjie starts at about 21:00 everyday. So it means you cannot take the cruise in the mornings.

Thanks, but I wasn't asking about the overnight cruises, I meant the fast local transport hydrofoil boats.

Oh, I am so sorry to misunderstood you.
I think you can arrange your trip like this: Yichang, Shennong Stream and then Fengjie. From Yichang to Badong, the earliest boat hydrofoil is around 07:00. The time is always changing. I took once at about 06:30 and my friend took it at about 06:50, so I advise you go to the Yichang Port to ask the exact time. The boat will take you about 2 hours to reach Badaong and then you can go to the Shennong Stream where you may need about three to four hours. Then you can catch the last boat from Badong to reach Fengjie at around 16:30. This time is more exactly.
Hope this time, the information is help.

Can i buy the ticket to yichang to badong in same day at the port?

Sandra, you need to buy the ticket when you arrive at the port. Currently, there is just one hydrofoil between Yichang and Badong. It accommodates 120 passengers. The whole journey is about 3.5 hours.