when is thelast time you can see the submarine at the museumofscience and industry?

The museum is open until 5:30 pm, the submarine is open until museum hours,but if you want to pay for the tour it's 30 or 35 min long.

You can look online, but I think the inside tour went every 30 min., with the last one at 3pm. You can see the outside exhibit, which is quite extensive, during museum hours.

Didn't see it the last trip.