Would 411a say that mayday declared to get attention and help when a serious problem arises that subsequently gets resolved and ends in a safe landing is unnessersary? I declared a mayday in a light aircraft a few years ago (in the UK talking to US military controllers providing a LARS service) when I had a serious problem because my initial low key attempts at getting help got nowhere. The mayday immediately got the help I needed and allowed me to resolve the rapidly deteriating situation. Does the fact I landed safely mean I didn't need to declare a mayday? I feel if I hadn't I wouldn't be here typing this.