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max descend speed for fc40

Discussion in 'Phantom FC40 Discussion' started by barnan, Dec 29, 2014.

  1. barnan

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    Hello,
    Is it possible to, when you put your throttle descend on maximum, in the software, it only descend at a max speed off 1 or 2m/sec.
    Now i do it only slightly max 1/3 on the throttle, and my fc40 wobble a lot, and descend quick.

    (sorry my english, i am from belgium)
     
  2. J.James

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    are you useing the normal stock fc40 propellers on it? and did you change any of the gain settings at all by any chance?

    Not sure what you mean by "when you put your throttle descend on maximum, in the software" I am not aware of any such setting in the naza software.
     
  3. IflyinWY

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    Hello barnan,
    WELCOME TO THE FORUM... I hope you enjoy your time here :D

    You may find this a helpful search tool: https://www.google.com/cse/publicurl?cx ... jku2ysgyhi

    Max descent speed depends on how you descend. Sounds like you are having issues with VRS. Here are a couple links to help you understand your "wobble". That "wobble" will make you descend faster than you want to... :eek:
    http://en.wikipedia.org/wiki/Vortex_ring_state
    http://www.copters.com/aero/settling.html

    If you descend vertically (straight down), you have your own rotor wash to deal with. BAD

    I can descend safely, at a very rapid rate if I maintain a high airspeed, in any direction, because I avoid my rotor wash. GOOD
    Here's an example: I push the right stick full forward and pull the left stick almost all the way back. I cover a lot of ground but for me that's not an issue. There is nothing around for miles. :D

    I am not sure if I am answering your question. Perhaps you could ask again, with more explanation. Maybe you could type in your language and use a translator.

    How about posting some video so we can see where you fly :?:
     
  4. J.James

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    That was my first guess that it was issues with VRS (vortex ring spiral) Which is why I asked about what props he is using.

    With the normal fc40 stock props VRS is an almost non existent issue for people flying the fC40s on the stock props and can usually land straight down as fast as it will go. Unless they switch over to the phantom vision style props then VRS can rear its ugly head and cause some real oh crap moments.
     
  5. barnan

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    I use the stock props.
    And in one off my first flights i think i had a VRS,i was descending quick and suddenly 4-5 meters in the air it suddenly turns around and crashed.
    The only thing i changed, was the min off the battery too flash red

    [/quote]Not sure what you mean by "when you put your throttle descend on maximum, in the software" I am not aware of any such setting in the naza software.[/quote]

    The left stick to descend(straight down), pulling the whole way down, is to quick to descend, now to descend i only slightly pull down the stick, when it is high in the air( don't want it to crash 100m in the air.
    The question is:
    now i pull down my descend stick a little and wait coming down.
    Can i somehow do modifications (in naza or tx software) that i can pulle down the descend stick the whole way, so it descend at the same speed when i pull it down a little bit?
     
  6. porg78

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    Hi, new to this forum and got my FC40 for Christmas so I might be totally off point in this but my understanding of the manual is that if you reduce the left hand sick to zero for 3 seconds then the motors stop. Would this apply in flight as I've never reduced them all the way down and could this be what's happened in this instance?
     
  7. probonic

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    The motors only shut off after 3 seconds if the Phantom has not descended in that time, so it will not happen in flight, only when it is on the ground.
     
  8. porg78

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    I've got another question if I may and I'm probably putting this in the wrong section so apologies if I am! Am I right in thinking that it will ascend at 6 metres a second? I've sent it up a few times really high but have still had a link up FPV to the camera so even though it's just a small dot in the sky then according to the FPV range it can't have been more than 100 metres? I timed it to 20 seconds whilst holding the left stick all the way up which would put it at 120 metres approx if the 6 metres per second thing is correct but I could still see the live footage? My transmitter beeps twice when I switch it on which according to the manual says that the range is 500 metres so in theory could I time it to approx 1 minute 20 seconds and still have control of the quadcopter to bring it back down safely?
     
  9. porg78

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    So if its a few hundred feet up you can hold the left hand stick fully down the whole time until it's landed even if it takes it 20 seconds for example and the motors won't shut down? Sorry if this is obvious, like I said I'm new to this and don't want it dropping out of the sky!
     
  10. probonic

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    Correct. The Phantom will come down at maximum speed for as long as you have the left stick down, and only when it detects it's not going any lower, i.e. it's assuming it's on the ground, then it would shut off the motors after 3 seconds or so. Although you wouldn't want to try that as you would have a pretty hard landing :p
     
  11. porg78

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    Nice one, thanks for clearing that up! It was taking ages for me to bring it back down to the ground!

    I've got another question if I may and I'm probably putting this in the wrong section so apologies if I am! Am I right in thinking that it will ascend at 6 metres a second? I've sent it up a few times really high but have still had a link up FPV to the camera so even though it's just a small dot in the sky then according to the FPV range it can't have been more than 100 metres? I timed it to 20 seconds whilst holding the left stick all the way up which would put it at 120 metres approx if the 6 metres per second thing is correct but I could still see the live footage? My transmitter beeps twice when I switch it on which according to the manual says that the range is 500 metres so in theory could I time it to approx 1 minute 20 seconds and still have control of the quadcopter to bring it back down safely?
     
  12. porg78

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    I was wondering if you know the answers to a few questions that I have?

    I've copied & pasted them from the thread that I made:-

    I've got a few questions that I'd really like answers to please by all the pro's on this site and I'm sorry if they sound stupid or obvious!
    The first one is this!
    Am I right in thinking that it will ascend at 6 metres a second? Does this apply in GPS mode,ATTI or just manual?
    I've sent it up a few times really high in GPS mode but have still had the link up with FPV to the camera so even though it's just a small dot in the sky then according to the FPV range it can't have been more than 100 metres? I timed it to 20 seconds whilst holding the left stick all the way up which would put it at 120 metres approx if the 6 metres per second thing is correct but I could still see the live footage? My transmitter beeps twice when I switch it on which according to the manual says that the range is 500 metres so in theory could I time it to approx 1 minute 20 seconds and still have control of the quadcopter to bring it back down safely?
    The second is if I program & set the S1 switch to manual mode will it behave like the Hubsan X4 H107 did in flight as I learnt the basics with a second hand one of these. I've also heard though that it's not recommended to select the manual setting?
    The last question (for now!) is can I program the S1 switch to activate failsafe and is it reliable as I don't dare fly it too far out at the moment in case it disappears! Ps, I always wait for a full GPS luck before I take off.
    There will probably be loads more questions as I progress and get more experienced/confident in flying it!
    Many thanks in advance,
    Ben