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Achieving longer Airtime

Discussion in 'Cinestar 8' started by Graydon Tranquilla, May 22, 2014.

  1. Graydon Tranquilla

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    Needing some feedback from some of you experts.....

    Experimenting with various scenarios, it seems that the "mixed airtime" is the item to watch in eCalc versus the hover airtime...... Watching the numbers carefully, one begins to see that hover airtime can remain the same for various prop diameters and/or pitches while the mixed airtime can go up and down a bit.

    In my case, I was surprised to see such low flight air times across the board for such a light payload..... in my case a 2 axis BGC carrying a GoPro3+ Black. The Panasonic GH4 comes later. All in all it seems that:
    a) A Hex would be more efficient for carrying a light payload
    b) I will need more battery capacity on my Cinestar Octo if I really want to get more airtime.

    7 minutes mixed airtime just doesn't seem like enough of a safe margin to me. airtime.JPG
     
  2. Matt Sharp

    Matt Sharp Member

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    Something seems off about those numbers.

    What's your actual AUW? 9406 grams seems really heavy for a gopro setup...
     
  3. Gary Haynes

    Gary Haynes Administrator
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    If your data points are entered correctly the setup needs 78% throttle to hover. That's a good indication that overall the ship is underpowered/overloaded. Doubt that you are using APC Electric E props.

    Also the value you should enter into the Model weight is better when you use the actual flying weight and then change the next cell to "with motors".
     
  4. Graydon Tranquilla

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    OK...... I tried it again with the total AUW, then selected incl. drive.....and the slightly improved results are shown below.
    This is the 1100mm Cinestar 8 which is slightly heavier. In any case IMHO - the "incl. drive" can lead to much confusion.
    Also interesting that a negative yoke twist on the props can narrow the range on the flight time between mixed and hover flight time values. airtime.JPG
     
  5. Gary Haynes

    Gary Haynes Administrator
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    Graydon do the numbers in your ecalc match what you are seeing for flight times, throttle, etc? Usually I find ecalc about +/- 10% but still a very good indicator of what happens with changes.
     
  6. Graydon Tranquilla

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    MR will have it's first test flight soon..... It seems that the eCalc prop database is limited and does not show any of the paddle props nor the Tiger Motor props to work from. So I adjust PConst for a custom prop after initial flights to get eCalc to align better with actual flight test results. How do others handle this?
     
  7. Jose Luis Ocejo

    Jose Luis Ocejo Active Member

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    I have also find out that some time the motor selection is missing motors for example U5 some times are listed and some time are not
    also some time the motor selection freezes and it doesn't allow more changes until you reset the page and start all over again hmmm?
     
  8. Gary Haynes

    Gary Haynes Administrator
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    Jose unless you buy a subscription to ecalc you will not see the entire motor list. U5's are listed if you have the subscription. They are not listed otherwise.
     
  9. Jose Luis Ocejo

    Jose Luis Ocejo Active Member

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    Thanks Gary I will subcribe
     
  10. John Butkus

    John Butkus Member

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    With all of the spam that has been coming through Feeefly Forums lately, when I saw the subject of "Achieving longer Airtime", well I assumed.......... :D
     
    Steve Maller likes this.

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