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Two, actually! Both built by the incredible Burt Rutan. From Wikipedia on the Rutan Voyager: "Sanctioned by the FAI and the AOPA, the flight was the first succ

Two, actually! Both built by the incredible Burt Rutan. From Wikipedia on the Rutan Voyager: "Sanctioned by the FAI and the AOPA, the flight was the first successful aerial nonstop, non-refueled circumnavigation of the Earth that included two passes over the Equator (as opposed to shorter ostensible "circumnavigations" circling the North or South Pole). This feat has since been accomplished only one other time, by Steve Fossett in the Global Flyer."

bscphil 7y ago
> that included two passes over the Equator (as opposed to shorter ostensible "circumnavigations" circling the North or South Pole) This is a really funny way of describing what I assume was a great circle path. It's certainly possible to do a "shorter ostensible circumnavigation" that passes over the equator twice: take an axis through the earth that passes through the equator twice, and take a circular path around that axis of any size. It's only a bias that says such a path counts less than circling the North / South pole. You can even circle one of the polls and cross the equator twice without it being a real circumnavigation. Fly a path around the Arctic circle, dip down just past the equator, and come straight back...
- dTal 7y ago
  It is possible to cross the equator twice without following a great circle, but it's not possible to follow a great circle without crossing the equator twice; perhaps this is the source of the confusion. In other words, you can reasonably say that crossing the equator is a necessary, but not sufficient, criterion for circumnavigation (it is of course not possible to cross the equator only once and return to your starting point). A good additional stipulation might be that the equatorial crossings must be separated by 180 degrees of longitude, plus or minus however tolerant you're willing to be.

bscphil 7y ago

> that included two passes over the Equator (as opposed to shorter ostensible "circumnavigations" circling the North or South Pole) This is a really funny way of describing what I assume was a great circle path. It's certainly possible to do a "shorter ostensible circumnavigation" that passes over the equator twice: take an axis through the earth that passes through the equator twice, and take a circular path around that axis of any size. It's only a bias that says such a path counts less than circling the North / South pole. You can even circle one of the polls and cross the equator twice without it being a real circumnavigation. Fly a path around the Arctic circle, dip down just past the equator, and come straight back...

dTal 7y ago
It is possible to cross the equator twice without following a great circle, but it's not possible to follow a great circle without crossing the equator twice; perhaps this is the source of the confusion. In other words, you can reasonably say that crossing the equator is a necessary, but not sufficient, criterion for circumnavigation (it is of course not possible to cross the equator only once and return to your starting point). A good additional stipulation might be that the equatorial crossings must be separated by 180 degrees of longitude, plus or minus however tolerant you're willing to be.