Level 1 cert kit recommendations

Discussion in 'Beginners & Educational Programs' started by Brown Lettuce, Apr 6, 2019.

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  1. Apr 26, 2019 #61

    Mike Haberer

    Mike Haberer

    Mike Haberer

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    OK, I'll play, so let's say you estimate this before launch because you know the potential maximum wind speed, the estimated max altitude and the rate of descent. Since you can calc all this up front, why would you launch? The suggested scenario also doesn't account for weather-cocking due to the lower level winds (likely to exist), hence the distance downrange the rocket goes into the wind, the reduced max altitude from angling over, etc., which can change the dynamics quite a bit as well. Besides, once you are outside of your field dimension, you're all too often screwed. From past (personal) experience, when you fly in high wind conditions, rockets tend to end up in...trees...on roofs...on power lines...in a creek. Been there, done that. Part of flying is knowing when not to fly. Just sayin'.
     
  2. Apr 26, 2019 #62

    Bat-mite

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    Agree 100 pct. I'm just trying to dispell the notion that some may have that DD is a foolproof way of not losing rockets. It helps, but offers no guarantees.
     
  3. Apr 26, 2019 #63

    Mike Haberer

    Mike Haberer

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    Plus one more thing. The drift is calculated by multiplying the time of descent (77 seconds) by the lateral wind speed (20 mph), not by the descent rate (90 fps - that is the vertical descent rate). 20 mph = 29.333 fps. 77 x 29.333 = 2,258 feet, substantially less than 6,930 feet. I would still question launching in 20 mph winds, but that said, likely doable on a drogue.
     
  4. Apr 26, 2019 #64

    Bat-mite

    Bat-mite

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    Woops. :oops:
     
  5. Apr 27, 2019 #65

    tOD

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    I just got my L2 on a DX3. AT J350 to 3171'. I built it with the 54mm motor mount but so far it's only flown on 38's. I picked up a 54mm J450 DMS motor that I'll try when I get the right conditions. I'm not ready to commit to 54mm hardware yet since K and L motors won't be something I'll be able to fly regularly. In fact my next build is going back to a 29mm motor mount
     
    Last edited: Apr 27, 2019
  6. Apr 27, 2019 #66

    Mike Haberer

    Mike Haberer

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    Yeah, I mean, for me this is primarily a visual and auditory "sport". Once it goes out of sight, it doesn't matter if it goes 5,000 feet or 20,000 feet, it's just "up there, somewhere" (unless, of course, if you're going for personal records or some such). I do like 29mm as well. I've had many a great flight on G's, plenty of oohs and ahhs from the crowd, you can see the rocket the whole time, they can't drift too far (I'm getting too old to chase them down...), and if the chute doesn't deploy, you get to see some pretty spectacular parabolic nose dives.
     
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  7. Apr 27, 2019 #67

    tOD

    tOD

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    The J350 took it to about the limit of my vision. I stuck an I364 black jack in it, that was nice, could see the whole flight.
     

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