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Lesson 1 - Mavic loses height when flying forwards in sports mode - crash at 30MPH :(

I noticed at the 2:01 mark that there were some wires going across the river. Probably why you climbed at that point. However, didn't help you in the end.

Correct but I had to go back for one more low pass in Sport Mode. That was my mistake.
 
Flying is all about air pressure.

As far as the mavic barometer is concerned, it probably was spot on on it's pressure altitude all the time.
While flying low you create a vortex of faster moving air between the quad and the ground, thus the pressure drops, making the barometer read a different pressure, causing the flight controller to adjust the altitude so that the pressure reads the same. Lower pressure causes it to think it's ascending, higher pressure means it's descending.

edit: there's also something like a pressure bubble that changes shape and location based on the pitch of the craft, causing it to drop a foot or so when you change pitch and start to fly fast.

Simple. Every multirotor, even an Inspire 1, 2 or M600 will do this. Basic principles of flight every 'pilot' should know.
 
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IMHO I believe it's more "angle of attack" that causes the Mavic to drop. In Sport mode during a fast acceleration the nose of the aircraft pitches down which causes the air to hit the top of the drone .... pushing the unit down. Basic principle of "Angle of Attack".

Add your pressure bubble theory and the fact that we started too low .... recipe for disaster.

I liked the advise of someone earlier in the post ..... start out higher and use the digital zoom to make it look close to the ground.

When I get my drone back Im going to try a couple of experiments. Im going to launch the drone in Sport mode from different altitudes. The higher the altitude the higher the density altitude. If I'm correct, the higher the altitude the less drop in altitude there will be. Less air to push the drone down. Any altitude difference will be easy to spot on the app.

I have so much to learn about quad vs fixed wing aerodynamics.
 
Oh man, sorry to hear about your drone. I can feel the pain over here. But why would you ever fly so low not in tripod mode or something more suited? I did some speed tests myself in 30 meters and the drone maintained the height well. This has been an expensive lesson :( Best of luck with your next drone!
 
so if this was in another modes besides sport, would terrain follow have saved it?
 
I have so much to learn about quad vs fixed wing aerodynamics
Important is to realise that a quad's airframe usually doesn't produce lift (and only little drag) itself. Only the props do. The drag (push down) caused by Angle Of Attack is compensated by the FC every nano second. But the FC listens closely to the barometer. That's the culprit here.
 
Thanks for your critique. It cost $119 to get it fixed. Lessons learned. I may be a rookie in regards to Drones but I have been in aviation all my life. I hope that moves me up the chain just a little bit. Also, since I was by myself when it crashed I doubt I was showing off.

And it is a toy !!

You Recorded it... You Posted it...You took Responsibility... Seeing what anything can do at that speed close to stationary objects is reckless at best...I know cuz I’ve done it!

Now calling a Flying Camera a Toy that is over $1k may be a Toy for those 1% Insanely Rich, but us 99% don’t like taking those risks too easily! However I know the risks as I made that mistake flying close to Time Square. Died a Horrible Death[emoji33]
 
You Recorded it... You Posted it...You took Responsibility... Seeing what anything can do at that speed close to stationary objects is reckless at best...I know cuz I’ve done it!

Now calling a Flying Camera a Toy that is over $1k may be a Toy for those 1% Insanely Rich, but us 99% don’t like taking those risks too easily! However I know the risks as I made that mistake flying close to Time Square. Died a Horrible Death[emoji33]

Risky flights are the most fun! For me anyway :)

(Lost first Mavic in the 2nd month of ownership)
 
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