Al,
I certainly wouldn't class myself as an expert in this type of aircraft, although I'd guess your numbers sounds reasonable. However, I wonder if a 1/13th share of this type of aircraft is a practical option? The only types which I've seen shared by this many people before are the very slow, often single-seat type of aircraft which no one would ever seriously consider taking any kind of distance. With 13 people in a group, I'd imagine there could be a lot of bad feelings if someone wanted to take the aircraft away for a weekend, or even for a day, from time to time?
FFF
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