As refuelling stops go, the one at Darwin military base on November 9, 2014, was eventful, for more than one reason it turns out.
The air force Boeing carrying John Key, and a load of officials and journalists, stopped to refuel on the way to the Apec leaders' summit in Beijing.
Mr Key was whisked off to the VIP lounge but emerged a short time later with Tony Abbott, wearing tight jeans and snug polo shirt.
With Newstalk ZB's Barry Soper providing a mock running commentary for the onlookers, the two Prime Ministers embarked on an inspection of each others' planes, first Mr Key's big Boeing and then Mr Abbott's smaller, more modern one, where they stayed for a good 25 minutes with their senior advisers.
It turns out Mr Abbott's plane was where Mr Key and the Australian PM had a conversation about the next Secretary-general of the United Nations.
It's when Mr Abbott said Australia would back Helen Clark, the former New Zealand prime minister.
Mr Key's office sent a letter from him to Mr Abbott the next day, while he was still in Beijing, recapping the offer.
Mr Abbott confirmed his commitment in writing and the exchange of letters in November 2014 was disclosed a few weeks ago by the Australian newspaper.
The paper also made the point that at the time, Mr Abbott knew that former prime minister Kevin Rudd harboured ambitions to seek the post.
But that was not just a by-the-way; it was the point of the exchange of letters.
It was an idea instigated by Mr Abbott, so if Mr Rudd approached him seeking the Government's support for his candidacy, Mr Abbott could say he had already given a prior commitment to support Helen Clark, who is yet to formally declare.
Mr Key quite properly has said he does not expect the commitment to apply to Mr Abbott's successor, Malcolm Turnbull, and his Government.
That Mr Abbott did not consult Foreign Minister Julie Bishop, let alone the Cabinet, probably rendered the commitment worthless anyway.
Mr Key told reporters this week that he expected he and Mr Turnbull would discuss the issue during Mr Key's visit to Sydney.
It is a safe bet that if Mr Rudd declared his candidacy, Australia would publicly support him.
But it is hard to see there would be any enthusiasm for a vigorous campaign on his behalf in the way Mr Key is promising to lead for Helen Clark, in the event she declares.
Mr Key's latest line this week was to say he would lobby every leader of every country he knew to help her, that New Zealand would do all it could to support her and finance her campaign.
There is little downside for Mr Key in supporting Miss Clark. She is still a highly respected and popular figure in New Zealand.
The issue has caused more heat in Australia.
Rudd loyalist and former deputy Anthony Albanese said if Australia did not support Mr Rudd, if he stood, it would be like supporting the All Blacks over the Wallabies.
Long after politics, Mr Rudd remains a divisive character and magnet for vitriol.
Right-wing commentator and UN sceptic Chris Kenny in the Australian said that in many respects Mr Rudd was perfectly suited for the UN job.
"Here is an organisation whose essential problem is one of grand ideals meeting ineffective implementation, of empty posturing triumphing over pragmatic solutions...''
In comparison to Miss Clark's record, his is pitiful.
Her record was of uniting a highly factionalised Labour Party and leading it into Government for three successive terms.
He was dumped as a sitting Prime Minister two and a-half years into his term by former colleagues who called his management style chaotic and dysfunctional.
He then served as Foreign Minister in Julia Gillard's Cabinet but ran a campaign of destabilisation against her, eventually ousting her for a brief three months before losing the 2013 election to Mr Abbott.
It seems Mr Rudd has found his vocation working in a think-tank in New York, in which he can bring his expertise on Asia to bear.
Miss Clark is in New York, too, running the United Nations Development Programme. With access to government leaders and foreign ministers all over the world, she is a relatively known quantity.
The Security Council will begin its selection process in July.
The General Assembly has asserted greater involvement for itself by inviting nominations, although a nomination is not a prerequisite.
The front-runner of those who have declared is considered by insiders to be Irina Bokova, Director-general of Unesco since 2009 - and from Eastern Europe (Bulgaria), which has never had a Secretary-general.
She was formally nominated last week and has an extensive CV with experience in politics and diplomacy.
Miss Clark has not declared. She has two choices.
The first is to sit back and wait for the contest to possibly knock out all contenders, then come through the middle in the event of a deadlock in the Security Council over a preferred candidate.
The alternative is to go on to the front foot and declare and openly campaign for the post.
The trouble with the waiting-in-the-wings strategy is people might not be convinced that you want it.
It says something about both Miss Clark and Mr Key that he is itching to campaign for her.
It says something, too, about both Mr Abbott and Mr Rudd that Mr Abbott would hatch an elaborate plan in Darwin as a means to turn down Mr Rudd.
If Mr Rudd were to subject his ambition to a dose of reality, he would recognise he has no chance, rule himself out and encourage the Australian Government to get in behind Helen Clark, as well.
● Audrey Young is The New Zealand Herald's political editor.
