Rate of Climb with a Wing?

[simonbryant]

Just a thought....would you get a better rate of climb with a Wing at an 80 degree rate of climb as opposed to straight up.....as by going straight up your reducing the angle of the wing against the airflow that would generate lift.....? :confused:

[Andy W]

Depends on how the model is set up, but in general, vertical is not an efficient way to climb. 60-70 degrees is usually optimal.
..a

[vintage1]

Andy is not far wrong, and the answer is a simple one. It depends on the power to weight. There comes a point where the model is going up vertically at a rate somewhat above stalling speed. At that point, there is no benefit to be had from the wing at all, so straight up with the wing edge on is the most efficient.

You'ld be seeing typially well over 100W/lb and a model with a fairly low wing loading to get there though.

Not many models are so equipped. I've got one that is about 150W/lb and that will not go straight up at all - about 50 degrees - but its high wing loading and fast.

[simonbryant]

ahh ok thanks guys.

So for my Unicorn wing....weight is 32oz and the thrust from the motor i believe is around 28oz, so what would be a good climb angle for maximum climb without running out of steam?

It will initally go up verticle very quick for about 8 seconds or so then the momentom slows down some what......

[Andy W]

There's no way to tell.
Simply fly at different angles and determine what looks best.
You could use a recording altimeter to remove the "fudge factor"//

[vintage1]

Whats its stalling speed and approximate glide angle?

And pitch speed.

Its calculable from that.
Or plug it all into motoalc and that will tell you.

I'd say about 40-50 degrees tho.

[adam_one]

The excess thrust power above stall speed can be used to accelerate the aircraft or climb, to accelerate and climb, or perform any manoeuvre, which requires additional power.
Thrust power = thrust × forward velocity
For the best angle of climb, i.e. to attain height over the shortest ground distance using maximum thrust available without flaps or high lift devices, the angle of attack (AOA) should usually be maintained at around 12º (the resulting angle of climb may be lower or higher than the AOA).
However, the angle of climb will also depend on the wind conditions at the airfield. Also note that AOA during the climb is only 3 or 4 degrees below the stall angle, thus care must be taken not to induce a "departure stall", particularly in turbulent conditions and with low thrust power to weight ratio.

The steeper the climb angle the more thrust is required to counter weight.