I am fortunate to have a 30l tank in my Nano (permitted under NZ Part 103 regs), giving me a safe 105+15 reserve minutes duration at nominal 15l/hr.
About 55 minutes radius for an out and return flight.
Trouble is many strips I want to visit need just a bit more, so I have to arrange for some fuel at my destination for the return trip.
The ideal would be to carry top-up fuel for a return leg if no fuel is available.
I have 10kg headroom to MAUW even with full tanks, so that would certainly let me carry an additional 10l.
I had a search around for motorcycle pannier bags that might do the job, and came up with the Rhinowalk 18l bags from AliExpress.
They fit OK on the Nano with a bit of non-standard mounting.
Pluses-
A 5l jerrycan fits snugly into each bag.
Room for some extra gear/oil in the fold-down section at the top
No modifications to the airframe
Minuses-
Not the tidiest look- would be better if they sat horizontal rather than sloping down, but it does give legroom for mount/dismount
Bulkier/heavier material than I need, but they were designed for motocross type riding
A bit uncomfortable on the butt, but I can live with that.
No noticeable increase in drag/fuel burn or handling, probably minor compared with that draggy rotor over your head.
With 30l in the tank plus 10l top-up I can now plan on 145+15 reserve minutes- about 70 minutes radius.
I’ve been looking at options similar to yours. I was leaning toward collapsing bags that take up less room when empty. The big issue has been securing it to the nano in a location not affecting W & B . I like your solution
Can you give us a picture of the 5 l jerrycan?