News about the airport closing spread from the public safety manager to the deputy directors to members of airport security to aircraft rescue personnel to administrative assistants and then to the rest of the airport employees. This is an example of which kind of organizational message?

Informal Grapevine

Explanation:

Grapevine communication is a casual, informal and private communication mode or scheme that occurs through false story and chatter inside the organisation.

It is a complicated word of mouth flow that links all of the organization's employees.

It works in both inner and external casual modes that can add to the company and profit from it.