Originally Posted by
jetBlueNYFL
Most airlines have jumpseat agreements with eachother, but that might only be for inflight crew and pilots.
A JetBlue flight attendant once told me that she flew JFK-London on MaxJet (all biz class) for about 25 bucks in taxes!
But the taxes to leave are ~5x that...

to the uK for the obscenely high taxes.