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Lost my phantom 1

Discussion in 'General Discussion' started by crchisholm, Mar 24, 2014.

  1. crchisholm

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    Well, my phantom 1 is now at the bottom of the ocean along with my gimbal and gopro black. I am left with trying to figure out what went wrong. I was flying over water and taking some video of some kayakers when I decided to bring it back to land. I realiszed that I was a little too high to clear a branch and tried to bring it down. I may have been a bit nervous because I was further from land than I had been, but was only about 3.5 minutes into a fresh battery. As I brought it down, about 20 feet from the water, it just dropped like a bomb and that was the end of it.

    I know that I am sometimes too quick on the control sticks and I wonder if I might have turned the motors off. My question I guess would be (because I can't test it now), if I bring the left stick all the way down while I am backing up to me (right stick down), would that be enough to turn the motors off mid flight even if I didn't go to the outside or inside with them?

    I know I'm ether going to build my own quad, or buy a p2 vision , but I will be stretching my budget to do either so I am trying not to make a stupid decission. If I go with the P2v I can afford one of two options...
    I can get a p2 vision with a integrated camera and the claim that is able to do FPV on a smart phone (android I hope) for about $1200.

    I can also get a p2 with their gimbal and no camera and by the time I buy the gopro black, I am at a similar or slightly higher mark. (it is probably obvious that I am a hobbiest, not a pro photographer)

    I sure would like to here other peoples opinions of these two options or even the DIY route (being fully aware of the name of this forum).

    Thank you for any input you might offer.
     
  2. syotr

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    Coming down too fast, you can get into a vortex state, falling through your own prop wash. .
    Sorry to hear you lost it. I have had some close calls, especially when loaded. I always attach floats when flying over water and mount the GoPro in the waterproof case. I am now building a waterproof quad.
     
  3. ericdes

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    You are at least the 4th story I read in the last 2-3 days that either lost or crashed their Phantom because of vortex ring state.

    Sadly none of the pilots knew about this phenomenon. I know it certainly isn't DJi's design or fault, as this has been since the helicopters are around, but it would be proactive from their part to mention this either on their site or in the box.

    It is a fairly easy thing once you know about it, hurts when it means you lose your Phantom in the process.
     
  4. ElGuano

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    It's probably vrs, but if your left stick was really down the entire way and you kept it there for 3 seconds, you disarmed your motors.

    I never descend more than 2-3 m/s. That's left stick down less than halfway past center.
     
  5. 9Jamie

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    [​IMG]
    :geek: The vortex ring state can be completely avoided by descending on flightpaths shallower than about 30 degrees (at any speed).
    :ugeek: For steeper approaches, vortex ring state can be avoided by using a speed either faster or slower than the area of severe turbulence and thrust variation.
    :oops: At very shallow angles of descent, the vortex ring wake is shed behind the helicopter.
    :evil: At steep angles, the vortex ring wake is below the helicopter at slow rates of descent and above the helicopter at high rates of descent.
     
  6. RogerClark

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    There was another posting a few days ago, where someone thought they'd also turned the motors off in-flight, possibly by having the throttle too low.
    Someone also posted that they thought they had turned the motors off completely by using the command sequence positions in-flight.

    However in your case, if you were coming down slowly, the vortex ring thing sounds more likely.

    Even if you had crashed into the ground, there would be no way to tell, as there isnt a flight log available on the Naza AFIK.
     
  7. TomBro

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    I was watching a video last week with some fellow filming his homemade quad in action when it suddenly inexplicably fell out of the sky like a stone into the river or lake he was flying over. Lucky for him his machine was waterproof and buoyant so he quickly recovered it. Cause turned out to be a broken prop, apparently they don't fly well on 3 legs.
     
  8. crchisholm

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    I am now making plans to buy a replacement phantom but this time the p2, and also a new gopro 3+. This makes it imperative that I understand as much as possible what happened to the p1. After reading about VRS and reading the posts here, there seems to be three likely causes....

    1) Holding down the throttle for three seconds and turning the motors off: I was only about 30 feet in the air when I started my decent, so I suspect that 3 seconds would have flown me into the water before it had a chance to turn the motors off. I don't think that was the cause.

    2) Prop failing or some other mechanical issue: I will never know. Since the quad was not retrievable, I can not rule out or rule in that cause. As much as the image of the quad falling into the water is burned into my memory, you would think I would see a piece of a prop falling, but who knows.

    3) VRS: I suspect that this is a good possibility, but this raises another question: My neighbor has a 350qx which is much more responsive and faster than my phantom was. He is a pretty good pilot and tends to really put this quad threw some amazing movement. One thing he does is bring the quad down from great height with the stick all the way down and it comes down very fast and then he stops it 20 to 50 feet above the ground. It seems that this is exactly what I should not do to avoid VRS. Can anyone tell me why maybe he does not seem to run into this problem even though he can drop a lot faster in a straight line than the phantom could. Am I still not understanding this phenomenon?

    Thanks for all your comments.
     
  9. LuvMyTJ

    LuvMyTJ ADMINISTRATOR
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    Sorry to hear this, it is every pilots fear. I am curious. If you were avoiding a tree, how was it to far from land to recover?
     
  10. crchisholm

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    Hi LuvMyTJ,
    I was out about 100 yards when taking vids, then wanted to bring back, so I started coming back with down right stick. At about 50 yards out, I realized I was too high for the tree branch on shore so I started bringing it down in preparation. It descended about three feet and then just fell the rest of the way into the bay. Where it fell is right over a navigation channell and I am no longer a strong enough swimmer to try and retrieve it. Being salt water, it wouldn't be worth retrieving anyway. When it went down, it was within site of a dozen or so kayaker and fishers and there was an audible grown from most. Several kayakers came over to see if they could help. People can be very compassionate some times.
     
  11. LuvMyTJ

    LuvMyTJ ADMINISTRATOR
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    I understand now, you were still out aways and preparing for it. Maybe you could find a friend who dives. If it hasn't been a long time I would attempt to recover it for rebuild. Even if it was just the shell that was salvageable. Also, most memory cards are waterproof, maybe the answer to what happened is on the footage.
     
  12. FangsCPO

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    Strong swimmer or not, the salt water would have provided you with more bouyancy but the strong current would have made it challenging. Salt water or not, it could have been saved if one of those kayakers would have gotten it for you. A really good rinsing out with copious amounts of water (after all, it's all ready wet) and then a thorough drying, you would have been surprised. I'm sorry for your loss. It's always scarying flying over water but it always looks pretty cool.
     
  13. LuvMyTJ

    LuvMyTJ ADMINISTRATOR
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    FYI TIP - For electronics use the strongest rubbing alcohol from the local drug store (90%) and after washing with fresh water flood it with alcohol, then dry carefully with compressed air, then air dry, then hope for the best. The plain water has minerals in it and is more likely to corrode the solder joints after some time passes.
     
  14. crchisholm

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    20 years ago and a different heart, maybe but the kayakers did try a and find it. The guy closest said it disappeared from the surface immediately and that the water right there was 20 or 30 feet deep in that channell. Fisherman around there call that spot "the hole". Believe me, I've been second guessing myself on every aspect of this since it happened. I probably could/should have done different, but knowing that gets me not a step closer to changing history.