Using Simple present tense for future event / Plan / Schedule

Can we use simple present tense to communicate our future plans? Actually recently I read some strange sentences like,

a) The plane arrives at 18.00 tomorrow.

b) She has a yoga class tomorrow morning.

c) Next Thursday at 14.00 there is an English exam.

So with reference to my above examples. Can I use simple present tense to tell my next day plans? Or Shall I use will in sentence? Or both will be ok?

E.g

Que: What are your plans tomorrow?

Ans a): Tomorrow early morning first I go to Morning walk and then I have a meeting at 10.00 with XYZ.

Or Simply I use will in my sentence.

Ans b): Tomorrow early morning first I will go to Morning walk and then I have a meeting at 10.00 with XYZ.

Answer

Yes you can. Generally the simple present isn't used to express what is happening right now. Instead its purpose is stating general truth about things in the present. But it can also be used to describe scheduled events in the future.

Your example: "The plane arrives at 18:00 tomorrow." would fall into that category. It describes the planes arrival at a time in the future, therefore is considered a planned/scheduled event. This applies to the other examples you listed.

Edit:

I have to add that you cannot express actions in this manner, which you plan to do in the future, even if they are 'planned'. For example this -

Tomorrow morning I go for a walk.

-would be incorrect, yet:

Every morning I go for a walk.

wouldn't, since this is simply a description of the routine and could be considered a general truth.