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  #1  
Old 02-17-2020, 08:24 PM
HenryMac's Avatar
HenryMac HenryMac is offline
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Default Hammerhead Shark.. The Rocket

This scratch build started as a result of seeing an Apogee Skonk Wulf and thinking that it looked more like a shark than a Nazi weapon of war.

Then when I was making the drawings for the rocket I saw a "Shark Week" slot machine that had a Hammerhead Shark and thought.. hmmm that would be cool.

The build has been really fun. It's got fin tabs and papered fins. I tend to build more for durability than altitude.

It sim's in Open Rocket just fine. I tried my best to make the hammerhead neutral.. meaning not an airfoil that would pitch the rocket.

So tell me.... what do you think?
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  #2  
Old 02-17-2020, 10:47 PM
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Pretty cool, as long as the forward area doesn't hurt stability.
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Old 02-18-2020, 08:11 AM
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What kind of wood did you use for the NC/head? It will need nose weight unless you used dense wood. Looks cool. Are P-40 shark teeth and eyes in its future?
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Old 02-18-2020, 08:34 AM
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Quote:
Originally Posted by tbzep
What kind of wood did you use for the NC/head? It will need nose weight unless you used dense wood. Looks cool. Are P-40 shark teeth and eyes in its future?


It's pine, and it will still need additional nose weight. 6.5 ounces per the Open Rocket simulation.

Not sure yet about the Walt Disney teeth...
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Old 02-18-2020, 10:05 AM
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With all that weight up there, and disruption of airflow over the fins, it would be cool if it wiggled side to side like a swimming shark. I'm afraid if it does wiggle, it will be more like a porpoise, but it's going to be a nice model, regardless. Looking forward to seeing it finished!
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Old 02-18-2020, 10:23 AM
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The only way to make the hammerhead neutral, or mostly neutral, would be to make it pivot.

The way it is now, if the rocket pitches up or down during flight, I am concerned that the hammerhead is likely to push it all the way over.

I mounted a camera in the nosecone of a rocket so that it stuck out one side, sort of like half of the hammerhead. The rocket went straight up about four or five hundred feet then took a sharp right turn. I suspect it just happened to change its angle of attack so that the airflow hit the camera on its aide. The long distance between the camera in the nose and the CP acted like a lever multiplying the small force on the camera.
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Old 02-18-2020, 10:36 AM
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I predict a random flight pattern. The nose is going to try to chase the tail.
Even with 6.5oz nose-weight, the forces on that wide forward wing-like nose will cause erratic-at-best flight.
Ever see any other designs like this in flight ?
There is a reason why not. Lack of stability.
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Old 02-18-2020, 12:09 PM
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Quote:
Originally Posted by ghrocketman
I predict a random flight pattern. The nose is going to try to chase the tail.
Even with 6.5oz nose-weight, the forces on that wide forward wing-like nose will cause erratic-at-best flight.
Ever see any other designs like this in flight ?
There is a reason why not. Lack of stability.


And that's exactly what makes this a fun project.... If I wanted to follow the "me too" crowd I'd buy a kit.

We launch lonewolf style... nobody else around. It'll either blow or go, either way it'll be spectacular.
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Old 02-18-2020, 12:49 PM
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Flight should be great for laughs if nothing else...
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When in doubt, WHACK the GAS and DITCH the brake !!!
No DIRECT and MEASURABLE Harm=NO Foul advocate

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, if you have to ask, you probably aren't
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  #10  
Old 02-18-2020, 01:06 PM
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Quote:
Originally Posted by ghrocketman
Flight should be great for laughs if nothing else...


When in doubt whack the gas and ditch the brake?
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