ASG 29, Speed to fly

1st Official Post

    Hey does anyone know if the flight computer on the ASG 29 is able to calculate the speed to fly?

    Soaring in Aerofly is lots of fun, but the range in a limited time span is rather limited. I know I could just speed up and hope for the best^^, but using the speed to fly- principle probably would allow me to better judge how much I could speed up.:thumbup:

    I’m talking about something differently here. Keep in mind that soaring is a sport that heavily depends on the interplay between time and energy management. That’s where “Speed to fly principle” comes into play.


    If all glider pilots were recreational pilots wanting to fly slow, then the ASG 29 wouldn’t have 7 flap settings. Settings 4, 5 and 7 would probably suffice then.😅

    So I did the calculations for the speed to fly on the ASG-29

    Vertical movement of the air - corresponding speed to fly:

    0 m/s - 90 km/h

    -1 m/s - 125 km/h

    -2 m/s - 152 km/h

    -3 m/s - 176 km/h

    -4 m/s - 196 km/h

    -5 m/s - 214 km/h

    —————————————————————————————

    So how do you use it to fly faster?

    First you will have to guess your average climb rate when climbing in a thermal or a ridge.

    Then, you take your average rate of climb. Then find the equivalent sink rate in the table posted above, ignoring the negative signs of course. The corresponding speed to fly will be our new flying speed whenever the air isn’t moving vertically.
    —————————————————————————————

    EXAMPLE

    Say we’ve just climbed a thermal using an average climb rate of 2 m/s.

    So, what does our corresponding speed to fly become?

    Vertical movement of air - speed to fly

    -2 m/s —> 0 m/s - 152 km/h

    -3 m/s —> -1 m/s - 176 km/h

    -4 m/s —> -2 m/s - 196 km/h

    -5 m/s —> -3 m/s - 214 km/h

    With this, we can also figure out our speed to fly if we find a bit of sink.


    I believe I haven’t corrected for the fact that the vario’s on our ASG-29 display the pure rate of climb. Not the actual movement of the air. You would need to consult the glide polars of the ASG-29 to correct for that.

    For best use I would keep a safety margin between using the speed to fly and the ground. Below which you revert back to the absolute best glide speed, which is somewhere between 90 and 100 km/h. Happy gliding everyone!

    I will try to describe some things about sailing. I'm certainly not an expert in this area. There are more experts here than me, and they will correct me if I have written something inaccurately. I also put up tables from the flight manual I found online.

    I searched the net for ASG-29. I found this curve for straight flight polar on their website.

    Here, the flight speed is shown on the horizontal axis, and the corresponding sink rate on the vertical axis. There are two important points on the curve:


    1. The highest point of the curve is the minimum sink rate. It is recommended to circle the thermals at this speed, and at this speed the aircraft will stay in the air for the longest time.

    2. The speed at the tangent drawn from the origin to the curve belongs to the best glide ratio. At this speed, the aircraft will fly the greatest distance, so this speed is recommended for gliding. Of course, I think that in a race where the highest average speed is important, a higher speed is also recommended, as Martijn22 wrote, if I understand correctly.

    There are two curves in the picture. The dashed line on the left is the version without water ballast, the one on the right is the version with water ballast filled in the wings and tail. It can be seen that at higher speeds, the same glide ratio can be achieved with heavier machines, so a higher average speed can be achieved with the machine. At the same time, the sink rate is also higher. When the pilot releases the water from the tanks can also decide whether he wins the race.

    I found this flight manual on the internet. This is a motorized glider, very similar to the ASG-29, perhaps this is its predecessor. I will post a few pictures from this manual.

    https://ilec-gmbh.com/wp-content/uploads/2020/09/Flughandbuch_ASG29Es.pdf

    Airspeed indicator markings.

    Flap settings.

    Edited once, last by Small Planes (May 30, 2024 at 7:38 PM).

    Yeah, I found that same manual as you did and use it for flap settings. The manual is for an ASG 29 E (ASW 27-18E for EASA, probably to save money). As far as I can find the ASG 29 E is a motorized version of the ASG 29. With the motor folded away, the flight characteristics should be the same as the ASG 29, for the same weight and center of gravity.