Originally Posted by
NiclasB
Smott, re submitted flight plans: During my ATPL theory studies, our instructor (an MD-80 professional pilot) explained a "trick" to deal with marginal fuel/range: For a trip from A to B that passes C along the way, file A to C with B as alternate. When approaching C, if weather at B ok and fuel status good, i.e. contingency not consumed, declare "go to alternate". With this trick, he could use the alternate fuel to "extend" his legal range, of course at the expense of reduced options once at B...
Edit: Magplug beat me to it.
Yup, been shown this 'clever trick' by some morons early in my career, when flying for a somewhat shady charter operator. However, it's not clever and, in fact, not legal. If you re-dispatch in the air (which the above in-fact is), you are still supposed to have alternate, final reserve AND contingency fuel for the remainder of the flight.
Properly done, re-dispatch can save a couple of kg's and possibly prevent a fuel stop on the way, but it is not a license to operate without adequate reserves...