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  #1  
Old 03-10-2020, 02:46 PM
dholvrsn dholvrsn is offline
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Default Pop-pod idea

Yesterday and today I was wondering why pop-pods weren't built this way? Use a little more mass ahead of the coupler to kick the xerclod back a little more to unhook things. I'm guessing that this was tried back in the day and was more likely to Red Baron. Plus getting that streamer to unfurl from the forward tube.
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  #2  
Old 03-10-2020, 06:35 PM
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GuyNoir GuyNoir is offline
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Quote:
Originally Posted by dholvrsn
Yesterday and today I was wondering why pop-pods weren't built this way? Use a little more mass ahead of the coupler to kick the xerclod back a little more to unhook things. I'm guessing that this was tried back in the day and was more likely to Red Baron. Plus getting that streamer to unfurl from the forward tube.


So I've built pop-pods this way.

I added two small fins to the tube carrying the engine so that if the shock cord broke, the result would still be NAR legal (since tumble recovery pods require two fins per the Pink Book).

These pods results in VERY positive separation between pod and glider, but:
  • 1. The force of the ejection can bash the glider, depending on how the pod separates from the glider.
  • 2. The cord can break, hence the need for two fins.
  • 3. The shock cord can get burned, increasing the chance for separation.

All of those things can be mitigated, but in the cases where separation occurs, you'll need to be prepared to explain to the RSO what happened and why your model shouldn't be DQ'ed.

My $0.02. YMMV.
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Old 05-30-2020, 02:13 PM
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Aeronerd Aeronerd is offline
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Interesting idea but wouldn't the force of the eject charge shred or tear off the streamer?
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Old 06-01-2020, 10:03 PM
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georgegassaway georgegassaway is offline
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Quote:
Originally Posted by GuyNoir
All of those things can be mitigated, but in the cases where separation occurs, you'll need to be prepared to explain to the RSO what happened and why your model shouldn't be DQ'ed.

Ah, yes, the RSO equivalent of shoot first, but don't even ask questions later.

DQ anything "different", maybe change mind if flier successfully points out why the RSO blew it (sometimes futile, like the old RSO mentality that DQ'ed copter models that descended "upside down", regardless of no such rule).

Anyway.......

The best fix I know of to prevent Red Barons is the Spooler pop pod. No shock cord, nothing to tangle (by the time the streamer unspools, the glider is long gone). And at first, some RSO's had to be paper-trained not to automatically DQ pop-pods that dared have a lightweight nose section that simply tumbled down. Or a "third part", as though by rule a B/G could have no more than 2 parts. While three parts sounds hard ot find, not much more than any B/G with a pop-pod. The tumbling nose section takes longer to land than the pod, so it is usually downwind of wherever the pod landed. Also helps to paint the nose fluorescent. I put my name on the pod nose in case someone else finds it. And worst-case, those noses are so easy to replace. But I actually can not recall the last time I lost a nose section.


Bunch of models with Spooler Pods and "L Hooks"


The other end of the problem is the old "Xerclod". Because those old 45-degree type glider hooks pry off easily in wind and sometimes in flight. Also, often you could not swap pods too easily, it was usually one unique pod per glider (well, for years I used two glider hooks, and two matching slots for those hooks, which definitely made it difficult to swap pods.

In 1980 I came up with "L Hooks" for pod attachment. Interlocking hooks that had to slide horizontally 1/4" or so before disconnecting. Can't pry off. But those were to solve a serious problem I had with R/C Boost Gliders prying the pod off during boost if I made too much of an elevator pitch maneuver. The design worked great, but took some fiddling to build to work right, so I never tried it for smaller B/G's

But in the 1990's, I revisited the L-hook and came up with a mass producible resin cast version (did not get into casting until 1991). Came up with a nice version to use for FAI S4 boost gliders and have been using those ever since for all my B/G's.
The other great benefit of them is that any glider can attach any pod that uses the same cast hook version. No more unique pod for each glider.

RTV mold and cast L Hook set.
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Last edited by georgegassaway : 06-01-2020 at 10:20 PM.
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