The issues between burning biodiesel in your turbine helicopter and today are largely regulatory, not technical.
Thats not quite correct! Biodiesel is agressive to some plastic materials used for seals etc. and therefore not the same as normal diesel. Also its possible, that your fuelfilters could become clogged by parrafine. For this reason a diesel powered car ist not automatically usable with biodiesel. And if its certified, you have to change the fuelfilter at half of the normal intervals.
skadi