And speed uses fuel up rapidly. So it is an intercept speed then
slows down to dog fight or attack. These jets would have to be
tankers to fly high speed all of the time.

Some jets have spare gas tanks that are dropped before speed.
They use the tanks to take off and carry aloft a heavy arm load.
It gives an added range over the stated range of a bare bone plane.

On 10/21/2012 7:29 PM, hal lillywhite wrote:
On Oct 21, 5:16 pm, Bill Shatzer wrote:

Set your Google search engine to Boeing X-45 or Northrop X-47B.
Hypersonics aren't remotely maneuverable with meat-shields aboard.

Neither the X-45 nor the X-47 are hypersonic. They are not even
transsonic; they have a top speed in the Mach 0.75 - 0.8 range.

Interesting. I haven't found how maneuverable they are but that is
likely to be one of the big advantages of unmanned fighters. The
human body can take only so many g's, even with a g suit. Take the
pilot out and you remove that restriction. And while pure speed is an
advantage in some limited situations, maneuverability is likely to be
more useful in general. A Mach 2 fighter might be able to fly by and
hit a fixed target, then get away. However if that target is taking
evasive action the speed can even be a disadvantage, taking the
fighter way past the target.