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Old 02-12-2018, 12:55 PM   #11 (permalink)
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Hinge it at the top, bottom or mid-point (for minimum gaps).

http://i.ebayimg.com/t/RC-Model-Airc...uLQ~~60_35.JPG

This is for an R/C model airplane, but the construction is very simple. You could use four of them, or make you own.

Also — Retractable skegs.

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Old 02-12-2018, 01:01 PM   #12 (permalink)
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Quote:
Originally Posted by freebeard View Post
maximum approach/departure angle at 10.5%
.
10.5% grade = 6° angle. (Had to look it up)

Bungie's would be great for the experimental stage of the project. For the long-term I would prefer something a little more resilient than rubber filaments.

I like option B better with a top hinge. A bottom hinge requires armadillo slipping plate armor crossbred with a slinky in order to allowed to articulate and accordion
The bird cage/ skin supporting structure would have to be extremely rigid(read heavy) to survive the torsional load applied to cause it to slide up an example of .A

I was thinking more in terms of MotoGP for the skid points extremely abrasion-resistant bolt on out of the box at this time 2 pucks are $59
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With the air dam I experimented with I went beyond what I saw as an acceptable lower limit just to determine how far I could go before I would start hitting the ground 2.5' forward of the contact point of the tires at 10 in of height is where I ran into the ground on the aggressive driveways the normal driveways that don't have chunks of pavement missing from their impact points, 10" was just fine. @8" parking blocks for Troublesome and driveways folded up like a taco shell. Fortunately this prototype was set up for rapid prototyping and it was not difficult to set right after an impact.
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Old 02-12-2018, 01:57 PM   #13 (permalink)
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Go to a track where they race motorbikes, the guys throw away the pads on their suits.

They should be adequate for the job especially if you have a free source of them.
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Old 02-12-2018, 03:55 PM   #14 (permalink)
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Quote:
Originally Posted by freebeard View Post
Your second option is preferable but I'd replace the servo with a bungee cord wrapped like the landing gear of a light plane. IOW it would deflect and return without powered control.

And add one or two wheelie bars or tail skids, so the boat tail itself doesn't impact the ground.
I like that idea!
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Old 02-12-2018, 04:02 PM   #15 (permalink)
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https://duckduckgo.com/?t=palemoon&q...e+landing+gear

Not talking about a strap with hooks on the end.
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Old 02-12-2018, 05:03 PM   #16 (permalink)
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Why would the bottom of the boattail be flat? We don't want the top or sides to be flat. Why not like this?



Also, I believe the angle freebeard shared refers to the angle from the ground to the back bumper, boat tail, or what have you.
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Old 02-12-2018, 05:40 PM   #17 (permalink)
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The thing I am fascinated with, today, is the M-80 Stiletto. Hydrodynamics is related to aerodynamics courtesy of Reynold's number.

The M-80 trades fineness ratio, as you see in corvettes, for modulating the interface with the medium it rides on. The 'underbody' is highly refined, a 'pentamaran'. The intermediate hulls are thickened for the surface-piercing propellors. (Their fluted blades are interesting in themselves. The forward aspect of the hull is viewable at:


https://newatlas.com/stiletto-experi.../5151/#gallery

Long story short — the underbody shouldn't be flat, it should be two pontoons to enclose the wheels and a Bucky Fuller 'air keel' in between. I'll leave how to apply that to a Prius as an exercise.
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Old 02-12-2018, 05:47 PM   #18 (permalink)
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That sounds like one of those car companies that died in embryo.
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Old 02-12-2018, 07:40 PM   #19 (permalink)
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Quote:
Originally Posted by Xist View Post
Why would the bottom of the boattail be flat? We don't want the top or sides to be flat. Why not like this?
You mean, more like this?
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Old 02-12-2018, 08:08 PM   #20 (permalink)
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I would say more like this:



I do not believe air would stay attached if you simply flipped the template because you are skipping the first half of the curve. This one has the curve from the peak of the roof until the termination you chose.

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