Max range speed?

[787steve]

I am newbie to rotary wing ops. I am not looking to set a max range flight. But I have seen many posts of people who ran into difficulty in a RTH situation being told that they should descend to minimum safe altitude and proceed in sport mode at max speed to recover.
My background is in fixed wing ops. In that world, you would be recommended to proceed at max range speed, which would differ greatly from max speed. I know the dynamics are different for quads, but I am wondering if the max speed advice is a proven technique, or just a universal assumption. Anybody have hard data on this?
In the time being, my emergency RTH procedure shall be descent to min safe altitude and speed home, looking for a landing place along the way if battery gets too low.

Also, if you are very close to making it, (as I have seen in several videos), can you adjust the emergency landing battery to below 10% just to get those extra yards in case over water, or other hostile terrain?

thanks in advance for your considered responses

 

[bvsolutions]

In my experience the max range is achieved at about 30 kph. Switching to sport mode can almost double speed to over 60kph, but reduces range by 15 to 20%.

 

[787steve]

Thanks. I thought that might be the case. I will run my own tests as well.

 

[Anthony]

The reference to hight is to help with any head winds you might encounter on your flight back to your home point as with hight you often get an increase in wind speed ( not always ) so dropping you hight if it is safe to do so can help.

Also turning off you forward facing sensors will increase forward speed.( but disables obstical avoidance)

I always test RTH fully after every update but very rarely use it but it is a very good function.

Also may I suggest that you always use precision take off as this helps you in a number of ways with the mavic.

Remember one thing .....

It is much easier to land short and walk to your Mavic than fly it out of power crash it and spend a whole load of cash to fix it ..... if you hit 15% and you are still not home then point the camera down and land on the first flat piece of ground you can find.

 

[dbyantis]

I am newbie to rotary wing ops. I am not looking to set a max range flight. But I have seen many posts of people who ran into difficulty in a RTH situation being told that they should descend to minimum safe altitude and proceed in sport mode at max speed to recover.
My background is in fixed wing ops. In that world, you would be recommended to proceed at max range speed, which would differ greatly from max speed. I know the dynamics are different for quads, but I am wondering if the max speed advice is a proven technique, or just a universal assumption. Anybody have hard data on this?
In the time being, my emergency RTH procedure shall be descent to min safe altitude and speed home, looking for a landing place along the way if battery gets too low.

Also, if you are very close to making it, (as I have seen in several videos), can you adjust the emergency landing battery to below 10% just to get those extra yards in case over water, or other hostile terrain?

thanks in advance for your considered responses

Several of those RTH issue posts talked about flying it out until the auto-RTH kicks in, so they flew the MP "as far as possible", then on the RTH, encountered head winds that prevented the MP from making it back, so the real issue was power mgmt. I would not recommend going lower than 10% as you can render a battery useless by running it dry and you risk the MP just dropping out of the sky.

 

[SouthernComfort]

Turning off all sensors may help conserve battery life in an emergency situation. My advise would be to do your very best to avoid such a situation however.

 

[787steve]

Turning off all sensors may help conserve battery life in an emergency situation. My advise would be to do your very best to avoid such a situation however.

Yes. In airplanes we had procedures to escape from a low level windshear. The first three were, AVOID, followed by AVOID, and in case that doesn't work, AVOID! Seems like a good idea in this arena as well.