Hi i have a mini 4 pro which i supposed to get to 35mph in sport mode witch i can achieve with a fresh battery. If the battery gets to 60% or lower the max speed starts to drop to 27mph and keeps dropping even more afterwards. I had an extreme case where at 20% the max speed in sport mode was 7mph in little to no wind.
I did some experiments with ATTI mode which I put on cine via drone hacks: with 50% battery sport mode: 27mph but in ATTI: 31mph. I would conclude that the speed is not limited by tilt angle or available battery amperage. FYI the battery temp was 35°C during high speed flight.
Is any effect like this known or how does this happen?
Thanks for any input!
Have a look 
I read the thread but cant find anything relating to my drone since the speeds are well below what the drone is capable and the tiit angle is below 35° of and there were little to no wind effects. Is it normal that top speed drops significantly with a lower battery %? But why would it a bit faster in Atti if the battery is the limiting factor?
If I understand correctly ATTI on a Mini 4 can only be achieved by modifying the aircraft by using third party software.
I had an Inspire 1, an earlier generation odf DJI which fell in the sea when I applied full power with a low battery, I am assuming that DJI now have an algorithm that restricts motor revolutionsif the power demanded is likely to take the battery below a certain level.
Hence as battery percentage and voltage reduces the maximum power available is also reduced for safety - i.e. keeping the bird in the air.
That has some unpleasant implications for those who fly a mission with a downwind outer leg and then try to return against the wind with reducing power. It’s something that is a known problem for Inspire 2 pilots who have upgraded to the latest firmware.
Yes Atti mode can only be unlocked using drone hack but it can sometimes auto enable if you fly withour gps (indoor) so its a normal “feature” of the mini 4.
So you imply that Atti disables this power limit in some way. But then it should reach the full 35mph even at 50% battery and not only slightly faster than in sport right?
I have done some further testing light wind (5mph): In sport with 70% battery i could achieve 29mph GPS speed straight into the wind (which is still less than the advertised 35 mph airspeed) but if i fly downwind it always achieves the same speed as upwind while having less pitch of course. So it looks like a software that lets the drone achieve the same speed in all directions limited by the max speed into the wind.
In Atti it was of course significantly faster than in Sport because of the wind but the strange thing is that is even slightly faster upwind in Atti so the question is what could limit the sport mode when flying straight into the wind which does not apply in Atti?