This waver states
that they don't have to fill up the plane all the way so they can save
on fuel costs.

"Filling up" the plane is not a requirment. "Having enough gas" is
(where "enough" is defined in the regs and includes reserves). You
don't have to have "more than enough", otherwise that amount would be
what "enough" would be, and we're back where we started.

Now, "enough" means "enough to get to your destination, fly the
approach, go to the alternate, fly the approach, and fly 45 minutes at
full cruise". Depending on what you pick for an alternate, you may need
more or less gas. Depending on what you pick for a destination, the
same is true.

The "destination" doesn't have to be "where you want to go". What I
have heard some pilots do is to make the place they want to go the
alternate, and pick a "destination" that is short of that. This
requires less gas. If they manage to get a better tailwind, then by the
time they get to their destination (not where they wanted to go), they
may still have enough gas to get to the alternate (which is where they
wanted to go), AND fly to another legal alternate, AND still fly for 45
minutes. IF this happens, they re-file with the new plan and keep
flying. The risk is that if this does NOT happen, they will need to
land short of where they wanted to go.

It sounds like cheating, but safety is NOT compromised, because they
always have a place to land in the plan, and sufficient reserves.

Jose
--
The price of freedom is... well... freedom.
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