That is a great article. It is too bad they dont have more photos.

I scoured the article to find out how they refuelled - the details were buried towards the end. Wow, what a way to transfer supplies and refuel 'on the wing' with a truck speeding along on the ground. A feat in itself. To to do this around 130 times without a major incident is remarkable.

EDIT: I'm also disappointed in lack of photos of the aviators and the aircraft. I am hoping the plane is still preserved somewhere and there are recent photos of it.

Here's another article with a picture of the refueling:

https://disciplesofflight.com/flight-endurance/

The cessna take off speed is 100Km/h, does that mean that refueling truck had to go around that same speed, or maybe a little slower since the airplane did not have to rise?

Or did they have a modified wing?

Am not a pilot, but why would they need takeoff speed, rather than to just stay above the minimum speed before stalling? That $V_s0$ speed is more like 65Km/h.

Also important to note that's airspeed, not ground speed. If they're driving/flying into a headwind, the ground speed (the speed the truck cares about) is even lower.

I think stall spoed with full flaps is around 35 mph, so 50kph-ish

Yeah right around there for the 172. You usually do slow flight work right around 40kts

I build camera gear for 172s and fly (as passenger, not pilot) probably 20-30 days per year, sometimes much more, and I get nervous at <60kts at low altitude.

40kts IAS is I guess around the full flaps stall speed but you sure don't want to be doing that intentionally. At least not with me in the plane please.