Fuel
from the training manual, just so we can put this one to bed (unless there was serious contamination)
FUEL DRAINS
There are five sump drains and a firewall fil- ter drain in each wing. Drain locations are shown in Table 5-1.
LIMITATIONS
APPROVED FUEL GRADES AND OPERATING LIMITATIONS
Commercial Grades Jet A, Jet A-1, and Jet B, and Military Grades JP-4 and JP-5 are recom- mended fuels for use in the Super King Air 200 and B200. They may be mixed in any ratio.
Aviation gasoline Grades 80 Red (formerly 80/87), 91/98, 100LL Blue (same as 100L Green in some countries), 100 Green (formerly 100/130), and 115/145 Purple are emergency fuels. Emergency fuels may be mixed with recommended fuels in any ratio. However, when aviation gasoline is used, operation is limited to 150 hours between engine over- hauls. The number of gallons taken aboard for
each engine divided by the engine fuel con- sumption rate equals the number of hours to be charged against time between overhauls (TBO).
The pilot must be familiar with the consump- tion rate of his airplane and record the num- ber of gallons taken aboard for each engine.
It is recommended that the pilot refer also to the Limitations chart in the POH concerning standby boost pumps and crossfeed opera- tions when aviation gasoline is used.
Takeoff is prohibited if either fuel quantity gage indicates less than 265 pounds of fuel or is in the yellow arc.
I would also take this opportunity to defend a very well respected contributor to these forums who floated an idea based on his very considerable experience. Whilst it is true that some engines are extremely sensitive to mis-fuelling, the PT6 happens to be a very robust creature, and ... as we all know especially in the complex world of aviation, nobody knows everything at any one given moment. Everyone is fallible, and it is when one believes otherwise that stuff happens.