In his dark teeshirt and skinny jeans Max Key stood out from the suits who occupied the rest of the "first class" cabin, the Prime Minister's most senior aides and advisers.

Take a walk down the aisle of the plane they dub "Air Force One" and you will be joining some very exclusive company.

Because while on the surface it may seem like any commercial airliner, tickets to the Prime Minister's VIP jet of choice are by invitation only.

Attention was drawn to the plane when John Key's son Max posted a picture on Instagram of him sleeping on "Air Force One" on his way over to Australia. But it's not just the prime minister and his advisers who get to travel on the plane.

Tracy Watkins/Stuff Max Key disembarks from the air force plane after accompanying John Key on an official visit to Australia

The guest list for the prime minister's latest trip across the Tasman includes some of New Zealand's most powerful and richest men and women - Xero founder Rod Drury, Mainfreight's Don Braid, and rich lister Sir William Gallagher among them, along with some of the country's top lawyers, lobbyists and CEO's.

This is the power group that occupies the cabin directly behind "first class" where the prime minister and his senior staff fly. The Key family are also regular fliers. But this is the first time Max has grabbed nearly as much attention as his famous father. In his dark teeshirt and skinny jeans Max Key stood out from the suits who occupied the rest of the "first class" cabin, the Prime Minister's most senior aides and advisers. But it was his Instagram fame that captured headlines in Australia.

One cabin back from the business delegation are media, representing most of the country's major news organisation and - like the business crowd - paying only a few hundred dollars for the privilege of being on board the prime minister's plane.

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Behind them are military personnel, who occupy the back half of the "economy" cabin, some of them flown over to protect the plane while it's parked.

This is a passenger list that can change from trip to trip, however. The air force 757 has carried every one from World War II vets to kapa haka groups, school children, rival politicians, Pacific leaders and sporting ambassadors.

JOHN COWPLAND/FAIRFAX NX Xero's Rod Drury - a regular on the plane they've dubbed "Air Force One".

Air Force One is not the jet's official name - that's a rip off of the US Presidential jet. Over the years it has been known by various names, including "Spud One", in honour of former prime minister Jim Bolger.

Cost is an obvious bonus of travelling with the prime minister but it is not the only attraction.

Being part of the official party usually makes for a quick passage through customs and immigration, a blessing when heading overseas with the prime minister, whose schedule is usually a hectic race from one appointment to the next.

Host governments usually provide a police motorcade to speed the prime minister's passage through rush hour traffic but media only get to tag along sometimes. The prime minister's office and Ministry of Foreign Affairs and Trade make it their business to ensure the media get to where they need to be regardless - which is where ever the prime minister happens to be.

There are other good reasons to love the Air Force VIP jet. There's the food, which tastes real, not like the usual plastic airline fare. The wine list is usually first class.

And the air crew who bring round the food trolley and do the safety demonstrations are favourites with everyone and not just because of their big smiles and old fashioned manners. In an emergency you can just tell they've got your back.

Then there are benefits of having a plane that's not hostage to the schedule, as journalists from the New Zealand Herald and Radio New Zealand found out last week. When their flight to Auckland from Wellington was cancelled and they looked like missing the departure time Key kept the plane on the tarmac for an extra 45 minutes to make sure they boarded. The journos got there with just minutes to spare before the Air Force's 5pm departure deadline ticked over.

For the business men and women who score an invitation, meanwhile, there is an even more important draw card, and that's face time with the prime minister.

Drury, who has been on a number of the Prime Minister's trips, says Key usually tries to get around every member of the delegation during the flight for some one on one time. In Sydney, the 27-strong delegation also shared a private breakfast with the Prime Minister. But during the flight, Key usually makes it down the back of the plane as well, hanging out in the aisles to talk to media, business people and air force crew.

Drury says the fact the guest list for the plane trip is so exclusive is one of the big attractions and not just for that face time with Key.

It's a small enough group to catch up with other leaders and compare notes with what's going on in their areas of business, or the economy.

"It's one of those things where you actually get to hang out with the CEO's so that's quite cool and you actually get a bit of quality time with John and some of the other ministers as well. And for us because we're such a big business in Australia as well so it's right to be there. And it's cool because New Zealand from a business-Government point of view actually has quite a good reputation, that it just really helps. A lot of the lessons we've learned we're able to apply to Australia and all the banking relationships and all those sorts of things we have go right through to the Australian parent company so it's a really worth while trip for us.