P4 Flips Backward On Takeoff

[Ricrhys]

Manual all the way from now on!

 

[sar104]

Full throttle on take offs!

I’ve never used auto takeoff, but I was a little surprised at the motor speed profile. I guess I should compare it to a regular manual takeoff.

 

[N017RW]

I’ve never used auto takeoff, but I was a little surprised at the motor speed profile. I guess I should compare it to a regular manual takeoff.

I've always believed full power at take-off gives the MC full dynamic range to then reduce motors' speed as required to maintain stability. I understand this may scare some folks as they belief is that slow and low is the best thing but nothing adds a margin of safety to enable correction(s) more than altitude.

It's the way I've always flown from planks to CP-helis.

Has always worked for me with no 'ground looping'!

 

[sar104]

I've always believed full power at take-off gives the MC full dynamic range to then reduce motors' speed as required to maintain stability. I understand this may scare some folks as they belief is that slow and low is the best thing but nothing adds a margin of safety to enable correction(s) than altitude.

It's the way I've always flown from planks to CP-helis.

Has always worked for me with no 'ground looping'!

That’s always been my strategy too - the same as for any aircraft - full throttle to get in the air and then dial it back. And since this is not really manual control, the FC always has the fine control needed for maintaining attitude (and position in GPS mode). I’ll post a manual takeoff comparison.

 

[Ricrhys]

That would be interesting to see.

 

[Ricrhys]

You can see the two spikes that show the backing off of revs before it goes for it that I mentioned earlier, any idea why it would be doing that instead of just getting it in the air to start with?

 

[sar104]

You can see the two spikes that show the backing off of revs before it goes for it that I mentioned earlier, any idea why it would be doing that instead of just getting it in the air to start with?

It does those on manual engine start, so I don't think that's part of the actual takeoff sequence. It would also be interesting to start the motors manually and then request auto takeoff.

 

[Ricrhys]

Got out for a flight today and had my first manual take off, much better.

 

[longdog]

Seems this was not the case, but if your props are on backwards, you’ll flip over on take off.
Nice pic btw!!
Earth is a beautiful place!

 

[PaulR]

Morning,

after updating the firmware the last two times I have been out with my P4 (standard) its flipped over backwards on take off, not every time though, I was using DJI go4. The first time I put it down to a combination off wind and not the flattest take off spot, admittedly it was a little windy but no more than I would usually fly in. After that first time I recalibrated the IMU then took it out yesterday and it happened for the second time, I held it in the air and took off from there and it flew fine, it's knocked my confidence a bit but I'm wondering if its something I'm doing/not doing?

Thanks in advance

Ric

check you props for notches. mine did that and all i had to do was change props.

 

[Ricrhys]

check you props for notches. mine did that and all i had to do was change props.

Now thats interesting, will post a photo later.

 

[Ricrhys]

A fair while back my drone flew over my van and one prop clipped my CB aerial, I've flown many times since this and not had a problem, and being new I thought well crap! but all seems ok, but as you have said that about the notches I thought I'd post the pics of the prop that took the hit, coincidentally since the second flip I've been using new props and had no problem but have only used manual take off.

 

[normr]

Why not use an app like Hover to see what your wind speed is before you take off, if it’s very high, the app will warn you

 

[Ricrhys]

I used to be on the Lifeboat crew here in Aberystwyth, they have a live online weather station which is very close to where I took off, I used that to check wind speed in real time, it was within what I'd taken off in before but yes a bit windy/gusty. Next time in in work I'll pick up one of the old hand held anemometers that have lapsed calibration but will be more than accurate enough.

 

[rkingsb353]

Thanks for the quick replies, I've only used auto take off and I just let it do it's thing till it's hovering and stable, should I be applying power myself during this auto procedure? and yes you guessed correct, this is my first real drone so I'm pretty green!

With 2 1/2 Year’s of fly I have always used auto take off with no problems.

 

[GadgetGuy]

I occasionally fly from areas that require hand launching, and use the Auto takeoff option in the app, while hand holding the aircraft in the other hand. It works, but it really doesn't seem like it provides enough lift to hover properly at chest height, without still holding it, so I have to give it left throttle before I let go. Only time I had a backwards flip upon manual launch was when the aircraft was precariously perched on a too narrow post, and the initial light revving of the motors tipped it slightly, and it fell off backwards. Need to give a solid left throttle ASAP.

 

[Andy9]

Maybe this all is right maybe not. Just to put that all is a bit relative.
I have the drones for a 3 years now so I'm pretty familiar with it.
I prefer manual take off. I like it more than auto. I let the motors spin for a while than I slowly lift the AC to 2-3m level. I've never performed any issues with it.
I have P3A and P4P and I do the same at both.

 

[sar104]

Maybe this all is right maybe not. Just to put that all is a bit relative.
I have the drones for a 3 years now so I'm pretty familiar with it.
I prefer manual take off. I like it more than auto. I let the motors spin for a while than I slowly lift the AC to 2-3m level. I've never performed any issues with it.
I have P3A and P4P and I do the same at both.

If that works for you then great but, in general, gentle takeoff maneuvers of the kind that I think you are describing have always been prone to causing the aircraft to tip over.

 

[Method007]

Remember when DJI use to recommend a slow throttle up to take off? What was that? So many people were flipping their phantoms.

 

[sar104]

Remember when DJI use to recommend a slow throttle up to take off? What was that? So many people were flipping their phantoms.

I do. For example from the P2 manual, 6.3.5: "Push the throttle stick up slowly to lift the aircraft off the ground."

Never was good advice.