I think this should work:
Code:
DoCmd.OpenForm "User Input", , , , acFormAdd
'Forms!"User Input".TabCtl0.DataEntry = True
Me.Visible=False ' usually you hide the Main Menu in case there are controls on it like user name that you need in other places, if not close it DoCmd.Close acForm, "Main Menu"
Are the subforms on the other tabs bound to the same Projects table, just different fields? if yes you do not need the subforms, just select all the controls on the subform(s), copy, delete the subform, click inside the tab and paste.
Cheers,