Lakeroadster's "Hammerhead Shark"

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BABAR

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Nice, you need a 45 degree off center forward shot.
 

lakeroadster

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@lakeroadster One of the things you haven't shown us on the .... Hammerhead is your recovery systems. What are you using for shock cord? How are you attaching it? What size chutes do you plan on using? Inquiring minds want to know. (And if you remember where this phrase came from you too are an old fart.)
I am lakeroadster..... and I am an old fart :computer:

The recovery on the Hammerhead is a bit unconventional:

The nose cone recovery is all on it's own. It weighs 10.6 ounces. It has a 12" piece of 75# Kevlar, attached to a #7 Eagle Claw Barrel Swivel via a key ring slipped through a custom made eyebolt that threads into the 3/4" bolt that threads into the nose cone. With an 18" Estes plastic parachute it's descent rate should be about 20 fps. There is no shock chord.​
The fuselage weighs 6.2 ounces and is pretty much standard recovery fair... a kevlar chord (attached to the motor mount) with a 24" elastic chord attached, via a #7 Eagle Claw Barrel Swivel, to an 18" chute that should yield about 16 fps descent rate.​
The fins are 1/8" balsa, through wall, and are papered. The body tube is a BT-60 with a full length C-60 internal sleeve. The intent was to end up with a durable rocket in regard to damage upon landing.​
001.JPG
 
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Greg Furtman

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I am lakeroadster..... and I am an old fart :computer:

The recovery on the Hammerhead is a bit unconventional:

The nose cone recovery is all on it's own. It weighs 10.6 ounces. It has a 12" piece of 75# Kevlar, attached to a #7 Eagle Claw Barrel Swivel via a key ring slipped through a custom made eyebolt that threads into the 3/4" bolt that threads into the nose cone. With an 18" Estes plastic parachute it's descent rate should be about 20 fps. There is no shock chord.​
The fuselage weighs 6.2 ounces and is pretty much standard recovery fair... a kevlar chord (attached to the motor mount) with a 24" elastic chord attached, via a #7 Eagle Claw Barrel Swivel, to an 18" chute that should yield about 16 fps descent rate.​
The fins are 1/8" balsa, through wall, and are papered. The body tube is a BT-60 with a full length C-60 internal sleeve. The intent was to end up with a durable rocket in regard to damage upon landing.​
@lakeroadster Thanks for the info. Yes, the Hammerhead head is pretty heavy and I think it is a wise decision to let it come down by itself. God, that is a big arse nut!
 

BABAR

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I am an old fart too. I am thinking you may want to add some elastic between that massive nose and the chute. Since you are flying without electronics, chances are you may get deployment somewhat before or after apogee, meaning that the nose is going to have some momentum. Depending on how much, you may shred your chute. Meanwhile, since all that is attached to the chute end of the elastic is the chute (as opposed to normal:attached to chute and rocket) there is no risk of “bounce back”. (Aka “Estes dent or smile”) from the recoil.

I learned this when I tried using black powder motors for a two stage, with a chute in a pod released when the segments separated. What I DIDN’T account for was that the booster was going full tilt velocity at time of staging.

Booster came down under a chute attached by only one riser! I just told everyone it was a round streamer.
 

lakeroadster

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I am an old fart too. I am thinking you may want to add some elastic between that massive nose and the chute. Since you are flying without electronics, chances are you may get deployment somewhat before or after apogee, meaning that the nose is going to have some momentum. Depending on how much, you may shred your chute. Meanwhile, since all that is attached to the chute end of the elastic is the chute (as opposed to normal:attached to chute and rocket) there is no risk of “bounce back”. (Aka “Estes dent or smile”) from the recoil.

I learned this when I tried using black powder motors for a two stage, with a chute in a pod released when the segments separated. What I DIDN’T account for was that the booster was going full tilt velocity at time of staging.

Booster came down under a chute attached by only one riser! I just told everyone it was a round streamer.
I'll take your advice... thanks! :computer:
 
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