Someone please explain what this pilot was up to.

[Stewartb]

• The main purpose is to gain altitude in a limited space.

 

[JohnDeaux]

Do you know where they took off from? I would imagine that it was already a backcountry strip, probably on a warm day at a high altitude, and that they simply didn't have the performance to climb high.

I'll attempt a non-pilot explanation here:

The key thing to understand is what we call "angle of attack" (AoA) which is the angle between the wing and the air rushing past it. Generally, the amount of lift the wing develops is directly proportional to the angle of attack, up to what we call the "critical AoA" which is where the airflow separates from the wing and it stalls.

Several things will affect AoA:
1) Speed. A plane that is flying slower has less air coming at it to be able to deflect downwards to develop lift. Slower speed = higher AoA.
2) Weight. A heavier plane needs more lift, and thus a higher AoA at a particular speed. (Gold is heavy stuff, too.)
3) Altitude. The higher you are, the thinner the air is, and the higher AoA you need for a particular speed and weight.
4) Heat. The hotter the air is, the thinner it gets, and the higher AoA you need for a particular speed, weight, and altitude.
* "Density Altitude" is the term used by pilots to describe this thinning of the air effect, combining the effects of heat and altitude into one term.

What we see in the video appears to have all of the above.

Cheesehead, thanks for the explanation. I do not know from where the flight originated, but like you, believe it likely that it was a backcountry strip, probably on a warm day (it's summertime here) and yes, possibly even at a fairly high altitude to start with. The southern state of Bolivar is very remote and with a lot of rugged terrain. There's a lot of illegal mining activity in the Guiana Highlands region and I believe that this particular plane was supposedly carring gold from that region, somewhere near the Brazilian border. I also believe that there were four persons on board the aircraft.