It had the added benign of acting like a drogue chute when full of water and a
main when empty
Sent from my iPhone
On Jan 30, 2017, at 4:37 PM, R Dierking <applerocketry@xxxxxxxxxxx> wrote:
Still, what a cool concept. Get rid of the majority of mass and you need
less parachute. Of course, some these guys would just jettison some black
iron.
JK
From: Wedge Oldham
Sent: Monday, January 30, 2017 4:14 PM
To: roc-chat@xxxxxxxxxxxxx
Cc: Michael Klett
Subject: [roc-chat] Re: Prohibiting Metal for Nose Weight
If I remember correctly the water ballast ejection system was actuated by the
chute opening.
Sent from my iPhone
On Jan 30, 2017, at 3:38 PM, <richsilv@xxxxxxxxxxx> <richsilv@xxxxxxxxxxx>
wrote:
Hey, Wedge, Kurt, any of the rest of you involved in the Saturn 5 project at
the Gates… I never got to see that project get more than, well, skin deep…
But anyway…
Didn’t the Design of that project (eventually) include some sort of
“Hydraulic Ballast” or something? Wasn’t it literally going to “leak water”
after liftoff at some controlled or controllable rate?
From: roc-chat-bounce@xxxxxxxxxxxxx [mailto:roc-chat-bounce@xxxxxxxxxxxxx] ;
On Behalf Of R Dierking
Sent: Monday, January 30, 2017 3:22 PM
To: Michael Klett; ROC Chat
Subject: [roc-chat] Re: Prohibiting Metal for Nose Weight
Ok, might be a little off-topic. But, this kind of thing
(discussion/consideration/thinking out of the box), is not only interesting,
but necessary. Otherwise, it goes like, incident, rule, incident, rule.
How much fun would that be. Or, how about, let’s do the same damn thing all
the time.
Remember, some people were discussing the current condition of the lakebed
and it’s not even February. Sorry, but come on guys! You all have been
going to the lakebed enough times to know this is kind of pointless now.
OK, I’m a pain. I’m actually being nice. I have hundreds of these topic
things. 😊
One thing that I know, when you bring something up that flies in the face of
established dogma, watch out! And, the reasons people will stand on to
defend; OMG.
For example, I once said that it was dangerous launching one rocket after
another without knowing the fate of the previous rocket. And, people said,
“what about the line of people waiting!” So, I replied, I have a bow, not a
powerful one, but I will stand by the low power pads, and shoot one straight
as possible into the air, and then immediately fire another. “You can’t do
that!” “That’s dangerous!”
I’m accumulated a list of things. But, I don’t keep track.
So, did the lakebed dry a little while we were chatting?
From: R Dierking
Sent: Monday, January 30, 2017 3:07 PM
To: Michael Klett; ROC Chat
Subject: [roc-chat] Re: Prohibiting Metal for Nose Weight
Not taking feathers. Considering the differences between pieces of metal
material and particles of other solid materials. Or, even water.
From: Michael Klett
Sent: Monday, January 30, 2017 2:49 PM
To: ROC Chat
Subject: [roc-chat] Re: Prohibiting Metal for Nose Weight
Yes, they weight the same but their volume can be very different. If the
volume difference is significant (lead vs. feathers) you may need more
weight to counteract the location of the CG of the weight.
On Mon, Jan 30, 2017 at 2:37 PM, David Smith <davew6dps@xxxxxxxxx> wrote:
Mike,
An ounce of BBs weighs the same as an ounce of sand.
Mass is Mass.
Dave
On Mon, Jan 30, 2017 at 2:34 PM, Michael Klett <xsive.guy@xxxxxxxxx> wrote:
No, mass is not mass. If I needed 4 oz of weight at the tip I would need a
pound at the middle (depending the length of the rocket, placement of CP an
CG etc. The point is the lever arm.) With lead I can get really close to
the tip. With feathers I'd need a lot more volume and the cg of the mass
would not be near the tip so I'd need perhaps a pound of feathers to be
equivalent to the 4 oz in moving the rocket's CG. The length of distance
between the center of Mass of the rocket without the weight and the center
of mass of the added weight determines how much weight you need to add. At
the tip "less is more".
But to your other point. Once I add the epoxy to keep the sand in place it
in fact becomes "trash" on the playa because of the epoxy. And if I've used
the epoxy and things come apart a 4 oz blob of sand/epoxy is going to hurt
just as much (probably) as a 4 oz blob of lead/epoxy.
Sorry, I don't see any benefit to changing materials currently. Although I
must admit your idea of using water for ballast on the way up and letting it
drain out on the way down to reduce weight at landing has always fascinated
me.
Thanks,
Mike
On Mon, Jan 30, 2017 at 2:19 PM, R Dierking <applerocketry@xxxxxxxxxxx>
wrote:
Sorry Mike. I believe you have not considered other things and went to what
you knew first.
Yes, mass is mass. I don’t think anyone needs a high density material for
nose weight. It’s just not that critical.
However, it would probably be impossible for me to convince anyone that
insists on metal material. But, what the heck, I’m trying anyway.
Richard
From: Michael Klett
Sent: Monday, January 30, 2017 2:15 PM
To: ROC Chat
Subject: [roc-chat] Re: Prohibiting Metal for Nose Weight
Richard,
My ballast of choice is lead BBs. They seem safely captured in epoxy. I
would also argue that by using lead they occupy less volume so I can get the
center of the mass of the BBs further in to the tip of the nose cone and so
I need less weight. Less weight is safer. If I tried to put the weight in
the AvBay for instance, I'd need a lot more weight to balance the rocket and
the additional weight would reduce the safety some.
Thanks,
Michael
On Mon, Jan 30, 2017 at 2:05 PM, R Dierking <applerocketry@xxxxxxxxxxx>
wrote:
Then why do even people with model rockets use metal?
The RSO wouldn’t want someone with an aluminum nose cone on a HP rocket but
accepts rockets with a nose containing bolts or lean shot. And, having
taken a nose apart that had bb’s set in 5 minute epoxy, the epoxy cracks and
releases the bb’s.
From: Allen Farrington
Sent: Monday, January 30, 2017 1:59 PM
To: roc-chat@xxxxxxxxxxxxx
Subject: [roc-chat] Re: Prohibiting Metal for Nose Weight
Tripoli has an official statement on using metal...you can find it on their
website here:
http://www.tripoli.org/Portals/1/Documents/Safety%20Code/Metal%20in%20Rocket%20Construction%20v2.0.pdf
Allen
Sent from my iPad
On Jan 30, 2017, at 1:50 PM, R Dierking <applerocketry@xxxxxxxxxxx> wrote:
Next time the NAR and TRA safety rules are revised, there should be
something about what kind of nose weight should be used or how about
shouldn’t be used.
Don’t the codes already say something about minimizing the use of metal?
Why add it? There’s no good reason why metal has to be used; there are
other things that would work fine.
And, just to get ahead of the one response that’s going to ask if a rocket
with other types of weight could hurt someone just as bad. Yes, I realize
that. But, again, if you think through the various failure scenarios, metal
(bolts, lead shot, bb’s, what ever…) is a poor choice for nose weight.
What other things could be used? Things that would be even better for both
safety and performance.
Richard Dierking
--
Justice shall flourish in his time, and fullness of peace for ever.
Psalm 72
--
Justice shall flourish in his time, and fullness of peace for ever.
Psalm 72
--
David P Smith
NAR 78668, L2
Amateur Extra, W6DPS
--
Justice shall flourish in his time, and fullness of peace for ever.
Psalm 72
