What if the project manager changes all of a sudden during the project at any phase (Due to resignation / Personal reasons / Accident). Does the Project charter also change with it?
If so, Who does the changes, what is the process/way to do it?
Project Charter is a document that formalizes the existence of a project and gives authority to the project manager to use organizational resources for the completion of that project.
Having said that, a change of project manager should not have any impact on the Project Charter. The only change would be to update the assigned project manager's name in the document. This would be done by the new project manager with the approval of current project sponsor.
Project charter is one of those few project documents(along with project's business case and benefit management plan) which are rarely changed during project execution and the reasons for that are obvious.
Project charter outlines the key objectives of the project & its success criterion (don't expect those to change too often - and if these are changing then may be this project is obsolete and instead a new project with new project charter is required)
Project charter also has the name of the project manager and authority level provided to the PM to run this project And if PM is changed then the Sponsor(who is the original creator(in most cases) & accountable of the project charter) can update the Project charter with new PM Name and the what is his/her authority level.
AFAIK - The PMBoK 6th Edition does not have any mention of the process to update the project charter and this is mostly because updating the project charter is rare event