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My approach to Level 1

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Kevin OClassen - 27 Apr 2005 12:43 GMT
Just thought I'd post something directly about rocketry, and a couple other
folks have described their approach to NAR Level 1. Here's my plan...

I've acquired my Skyripper H hybrid motor and most of the pieces of GSE...
I've learned a lot about some very obscure (and hard to find) gas fittings.
All the rocket pieces and materials are on order, and I finally bit the
bullet and ordered a flight computer-- I settled on the G-Wiz LC 400. I like
the accelerometer-based apogee detection, and the power output (supports two
batteries).

The rocket will be an overstable 4" x 72" (+/-) scratch built, G10 fins
(hopefully... I've gotten some tips from my cousin the machinist on cutting
and handling the stuff, and think I can pull it off. If not, plywood). Dual
deployment, ejection at apogee (drogueless -- 25' 9/16" tubular recovery
harness), a 54" x-form chute at 400'. Weight right around 5.5 lbs. If final
ground testing supports what I've found so far, I'll be introducing a
variation on main chute deployment, mostly applicable to hybrids. Of course,
none of it matters until the bird is flown and back in hand, undamaged, but
damn am I having fun planning. Complexity means failure points, and I've
always loved dancing with Murphy.

Barring the unforseen, at our Section's June launch I plan for a 1000' L1
certification flight on an H155 load, top speed of about 170mph. I took the
suggestion "low and slow" quite seriously.

Kevin OClassen
NAR 13578
Niall Oswald - 27 Apr 2005 13:51 GMT
> Just thought I'd post something directly about rocketry, and a couple
> other
[quoted text clipped - 30 lines]
> the
> suggestion "low and slow" quite seriously.

What size MMT are you putting in that? Sounds like it could be good for the
smaller HyperTek motors too (300/440CC).

I'm taking a similar approach, similar motor, but smaller airframe and only
single deployment. I'm looking at about 2000ft on a WCH H100.

I now have a head full of pipe fittings too!

I guess my approach can be summarised as 'KISS, SCHMISS'!

If I hadn't happened to win a 2.6" rocket that would take the motor, I would
probably have built something a bit smaller and sleeker. Then again, with a
relatively low flight using apogee-only deployment I can use my G-Wiz MC's
low altitude channel in 'apogee delay' mode and fire a backup charge. I am
considering a separate backup timer too, not really sure I want 3 charges
though, so I may go for having the separate timer and G-Wiz channel firing
the same charge via separate e-matches, if that makes sense.

Good luck, its nice to read of someone doing an interesting L1 :)

Signature

Niall Oswald
================================
http://www.bits.bris.ac.uk/niall
UKRA 1345
EARS 1151
MARS

Kevin OClassen - 27 Apr 2005 14:54 GMT
> What size MMT are you putting in that? Sounds like it could be good for
> the
> smaller HyperTek motors too (300/440CC).

38mm x 28"

I designed the rocket around the Skyripper H & I 38mm cases, since that was
the motor I ended up with. After my certification, it should fly to about
3000' on the SR I motor.

We fly from tree-surrounded small fields, and I really want to get my cert
flight back... hence the low altitude and the low main deployment.

I plan to start from scratch for L2.

> I guess my approach can be summarised as 'KISS, SCHMISS'!

I want that on a T-shirt.

Kevin OClassen
NAR 13578
Niall Oswald - 27 Apr 2005 16:36 GMT
> I designed the rocket around the Skyripper H & I 38mm cases, since that
> was
> the motor I ended up with. After my certification, it should fly to about
> 3000' on the SR I motor.

I take it the J won't fit then :( The SRS motors look nice - simple and
elegant, as well as shiny as anything :) My L1 rocket was never intended for
hybrids, but I made the MMT long enough for a 6-grain Pro38 with L2 in mind,
and that just happened to be long enough for an H hybrid.

> We fly from tree-surrounded small fields, and I really want to get my cert
> flight back... hence the low altitude and the low main deployment.

Ah, I guess I've been spoilt by my weekend visit to a site with massive
altitude potential!

>> I guess my approach can be summarised as 'KISS, SCHMISS'!
>
> I want that on a T-shirt.

Might have to do that in time for UKRA'04, when I plan to launch my L1. I
really hope it works! You will post up the results, wont you...

Signature

Niall Oswald
================================
http://www.bits.bris.ac.uk/niall
UKRA 1345
EARS 1151
MARS

Niall Oswald - 27 Apr 2005 13:52 GMT
> Of course,
> none of it matters until the bird is flown and back in hand, undamaged,
> but
> damn am I having fun planning. Complexity means failure points, and I've
> always loved dancing with Murphy.

Mean to say, same goes for me...

Signature

Niall Oswald
================================
http://www.bits.bris.ac.uk/niall
UKRA 1345
EARS 1151
MARS

AlMax - 27 Apr 2005 19:36 GMT
> Just thought I'd post something directly about rocketry, and a couple
> other
> folks have described their approach to NAR Level 1. Here's my plan...
>
> I've acquired my Skyripper H hybrid motor and most of the pieces of GSE...

> The rocket will be an overstable 4" x 72" (+/-) scratch built, G10 fins

That is a very nice rocket and motor to fly for your L1 Kevin !

I've flown the Skyripper H and I in a LOC Easy I-65 and it was a nice
filght.
J.A. Michel - 27 Apr 2005 21:35 GMT
Kevin,

Why do you want to dual deploy from a 1000' flight?  Going only to 1000',
you might want to consider single deploy.

I can appreciate wanting the complexity of electronics on a cert flight,
because I did my first electronics for my L2 cert.  I personally would be
more comfortable flying the "I" motor to 3000' and doing dual deploy.  You
also might want to consider boosting your second deployment altitude up a
bit, maybe to 800' for your first flight.  This gives a bit of extra time to
"work things out" if a chute gets tangled or something.  Go for the lower
deployment altitude when you're sure that your 'chute packing skills are up
to speed.

Those are some of my thoughts and experiences with dual deploy.  However you
decide to do it, good luck on your cert flight!

Signature

Joe Michel
NAR 82797 L2
http://home.alltel.net/jm44316

> Just thought I'd post something directly about rocketry, and a couple
> other
[quoted text clipped - 33 lines]
> Kevin OClassen
> NAR 13578
Kevin OClassen - 28 Apr 2005 10:02 GMT
> Kevin,
>
[quoted text clipped - 12 lines]
> up
> to speed.

Joe,

You've no idea how I've dithered about this issue. Your post recrystallized
the points I've considered, and reminded me of something important. Cheaping
your way out of a situation leads to problems. That's what's happened here.
Cheapie me was trying to save $60 by buying the G-Wiz LC instead of the MC.
Unfortunately the LC comes in *either* 400 or 800 foot main deployment only.
The LC will not let you choose deployment height.

Your post pushed the final button, durn it. I called Aerocon and changed my
order to a G-Wiz MC. So, LOL, the plan for my cert flight is now something
like "drogueless deployment at apogee, main ejection 3 seconds later". Might
end up being 800' for main deployment. Because of the way my recovery system
is set up, I have to use dual deployment, but the MC gives me the flex to
take the most reliable route.

Sempre Gumby!!

Kevin OClassen
NAR 13578
Niall Oswald - 28 Apr 2005 16:49 GMT
> You've no idea how I've dithered about this issue. Your post
> recrystallized
[quoted text clipped - 7 lines]
> only.
> The LC will not let you choose deployment height.

The MC has a bunch of useful features - not only the datalogging but you can
use the main channel as a post apogee timer, which I am planning to do on my
L1. Its also got the handy safety jack - you did order the 'remove before
flight' tag, right :)

> Your post pushed the final button, durn it. I called Aerocon and changed
> my
[quoted text clipped - 5 lines]
> is set up, I have to use dual deployment, but the MC gives me the flex to
> take the most reliable route.

It sounds like it will be a fun cert flight - doing it in style! If I make
that t-shirt, it will have 'The more failure modes the merrier' on the back
I think :)

Signature

Niall Oswald
================================
http://www.bits.bris.ac.uk/niall
UKRA 1345
EARS 1151
MARS

Jerry Irvine - 28 Apr 2005 18:21 GMT
> It sounds like it will be a fun cert flight - doing it in style!

Point.

Signature

Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to:01rocket@gte.net>
Please bring common sense back to rocketry administration. (too late)
Produce then publish.  http://www.usrockets.com
Ebay. http://tinyurl.com/6wlp8

Niall Oswald - 28 Apr 2005 22:41 GMT
>> It sounds like it will be a fun cert flight - doing it in style!
>
> Point.

I know that saucers are approved for L1 cert flights, but I would personally
be far more impressed with someone who pulled off a flight like the one
Kevin is planning (or dare I say the one I am planning) than flying a
saucer. That said someone might have been flying dual-deployment minimum
diameter rockets on G80's (or even better G hybrids) and just wanted a
simple cert flight to move onto H's.

Of course the KISS approach is not without its merits, if you want to
certify with minimumstress. I think half the fun is doing something
risky/complex though!

Signature

Niall Oswald
================================
http://www.bits.bris.ac.uk/niall
UKRA 1345
EARS 1151
MARS

Phil Stein - 28 Apr 2005 22:57 GMT
>>> It sounds like it will be a fun cert flight - doing it in style!
>>
[quoted text clipped - 10 lines]
>certify with minimumstress. I think half the fun is doing something
>risky/complex though!

I agree.  You guys are discussing stuff that shows some expertise.
Anyone can throw a saucer up.
Niall Oswald - 28 Apr 2005 23:27 GMT
>>>> It sounds like it will be a fun cert flight - doing it in style!
>>>
[quoted text clipped - 14 lines]
> I agree.  You guys are discussing stuff that shows some expertise.
> Anyone can throw a saucer up.

I will add that until I actually make a successful flight of my rocket, I
can talk all I like but I'm not L1 certed, 'Flier X' who used a saucer to
cert is and can fly H and I motors all they like!

Like I say though, getting over all that could go wrong (or at least cause
me hassles) will, for me make it more satisfying when I do certify
successfully. If it takes a couple of tries for whatever reason, never mind
(I really hope it doesn't, I'm trying hard to think of non-destructive
failure modes here!).

I'm sure this argument has been had out on here before, but I can see where
people who think saucers shouldn't be allowed for cert flights are coming
from. There are arguments either way, but if the flier is unknown to the
RSO, flying a saucer, IMHO, does not demonstrate the same level of
competence as flying a 'traditional' rocket (i.e. one with fins and a
parachute/streamer).  As I see it, its a bit like the difference between
taking your driving test in a manual or automatic car - if you can drive a
manual you can drive any car, with an auto-only license you've not
demonstrated competence at what is a fundamental part of driving a manaul
car.

Its not to say that the flier is (neccessarily) any less competent, but if
the RSO only has the cert flight to go on (lets say the flier has travelled
from a different part of the country, or is even making their first rocket
flight, or they've only flown saucers...all hypotheticals I know), how are
they to know if the flier can successfully pack a 'chute or determine the
stability of his/her rocket.

Flame away, just my thoughts. Saucers are cool, and they do satisfy the
requirement for a recovery as intended, but I'm not sure that flying a
saucer is a good test of competence for an HPR flier. Perhaps a saucer with
a 'chute, I don't know.

FWIW I have no issue with saucers (and their ilk) in general, I've seen some
very cool flights made with them.

*dons nomex underwear, hopes for intelligent and reasoned responses!*

Signature

Niall Oswald
================================
http://www.bits.bris.ac.uk/niall
UKRA 1345
EARS 1151
MARS

Phil Stein - 29 Apr 2005 01:20 GMT
>>>>> It sounds like it will be a fun cert flight - doing it in style!
>>>>
[quoted text clipped - 52 lines]
>
>*dons nomex underwear, hopes for intelligent and reasoned responses!*

I totally agree.  I know there are some (like Art Applewhite) that
totally disagree but that's just a combination of conflict of interest
& not knowing any better.
Jerry Irvine - 28 Apr 2005 23:28 GMT
> >>> It sounds like it will be a fun cert flight - doing it in style!
> >>
[quoted text clipped - 13 lines]
> I agree.  You guys are discussing stuff that shows some expertise.
> Anyone can throw a saucer up.

Stop judging either.

The variety of methods to achieve a stated goal is the spice of life.

Now if only the goal was reduced in stature to a merit badge, 90%+ more
of the population would qualify for access.

Signature

Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to:01rocket@gte.net>
Please bring common sense back to rocketry administration. (too late)
Produce then publish.  http://www.usrockets.com
Ebay. http://tinyurl.com/6wlp8

Niall Oswald - 28 Apr 2005 23:39 GMT
>> I agree.  You guys are discussing stuff that shows some expertise.
>> Anyone can throw a saucer up.
>
> Stop judging either.
>
> The variety of methods to achieve a stated goal is the spice of life.

Can't disagree with you there.

I guess what Phil is questioning is whether 'throwing a saucer up' actually
reaches the goal. On the other hand, if NAR/TRA/UKRA say it does, then it
does.

> Now if only the goal was reduced in stature to a merit badge, 90%+ more
> of the population would qualify for access.

How does this apply to L1 certification?

Signature

Niall Oswald
================================
http://www.bits.bris.ac.uk/niall
UKRA 1345
EARS 1151
MARS

Phil Stein - 29 Apr 2005 01:38 GMT
>>> I agree.  You guys are discussing stuff that shows some expertise.
>>> Anyone can throw a saucer up.
[quoted text clipped - 13 lines]
>
>How does this apply to L1 certification?

Jerry-

I don't see what the big deal is with needing a cert or not.  If you
don't have a cert and want one, you are going to build a rocket
weather you have a cert or not.  Either way, you fly that rocket.  The
only difference is how close a  look at it someone takes before the
flight.  Knowing it is a first flight, the typical RSO will look it
over fairly well anyway.  Also, you have a few people sign off.  If
you fail, you get to do it again - the same as if you had passed.
What is the big deal?  
Jerry Irvine - 29 Apr 2005 04:01 GMT
> >>> I agree.  You guys are discussing stuff that shows some expertise.
> >>> Anyone can throw a saucer up.
[quoted text clipped - 17 lines]
>
> I don't see what the big deal is with needing a cert or not.  

Mandated by NFPA-1127 is the ONLY reason.

That added rule was not self-regulation, it was self-destruction
codified.

> If you
> don't have a cert and want one, you are going to build a rocket
[quoted text clipped - 4 lines]
> you fail, you get to do it again - the same as if you had passed.
> What is the big deal?

Signature

Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to:01rocket@gte.net>
Please bring common sense back to rocketry administration. (too late)
Produce then publish.  http://www.usrockets.com
Ebay. http://tinyurl.com/6wlp8

Jerry Irvine - 29 Apr 2005 03:58 GMT
> >> I agree.  You guys are discussing stuff that shows some expertise.
> >> Anyone can throw a saucer up.
[quoted text clipped - 8 lines]
> reaches the goal. On the other hand, if NAR/TRA/UKRA say it does, then it
> does.

I think he is attacking anybody that does not agree with HIM:

Stein:
I totally agree.  I know there are some (like Art Applewhite) that
totally disagree but that's just a combination of conflict of interest
& not knowing any better.

> > Now if only the goal was reduced in stature to a merit badge, 90%+ more
> > of the population would qualify for access.
>
> How does this apply to L1 certification?

Signature

Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to:01rocket@gte.net>
Please bring common sense back to rocketry administration. (too late)
Produce then publish.  http://www.usrockets.com
Ebay. http://tinyurl.com/6wlp8

Phil Stein - 29 Apr 2005 01:26 GMT
>> >>> It sounds like it will be a fun cert flight - doing it in style!
>> >>
[quoted text clipped - 20 lines]
>Now if only the goal was reduced in stature to a merit badge, 90%+ more
>of the population would qualify for access.

Saucers are cool but as Niall said, building one doesn't show that you
can do several major things right.  I believe that showing that you
can do these thngs sucessfully were the reason that the cert process
was established.  If a person can't show me that I'm not going to cert
him.  Of course he can go find someone else that will.
Jerry Irvine - 29 Apr 2005 03:56 GMT
> >> >>> It sounds like it will be a fun cert flight - doing it in style!
> >> >>
[quoted text clipped - 24 lines]
> Saucers are cool but as Niall said, building one doesn't show that you
> can do several major things right.

>  I believe that showing that you
> can do these thngs sucessfully were the reason that the cert process
> was established.  

The cert process was established to simply show you can successfully
launch an H. I was there. I know.

> If a person can't show me that I'm not going to cert
> him.  Of course he can go find someone else that will.

Signature

Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to:01rocket@gte.net>
Please bring common sense back to rocketry administration. (too late)
Produce then publish.  http://www.usrockets.com
Ebay. http://tinyurl.com/6wlp8

Jerry Irvine - 29 Apr 2005 03:56 GMT
> >> >>> It sounds like it will be a fun cert flight - doing it in style!
> >> >>
[quoted text clipped - 27 lines]
> was established.  If a person can't show me that I'm not going to cert
> him.  Of course he can go find someone else that will.

You think this is about you? Ha!

Signature

Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to:01rocket@gte.net>
Please bring common sense back to rocketry administration. (too late)
Produce then publish.  http://www.usrockets.com
Ebay. http://tinyurl.com/6wlp8

David Weinshenker - 29 Apr 2005 05:26 GMT
> >> It sounds like it will be a fun cert flight - doing it in style!
> >
[quoted text clipped - 10 lines]
> certify with minimumstress. I think half the fun is doing something
> risky/complex though!

With me, it was more that I had a rocket that I had flown on G's and
felt that it really needed just a bit more impulse, so I pulled out
the cert blank that I'd been carrying around in my range box, lined
up a witness, and said "hey everyone watch this - I'm gonna fly an H
now..."

Level 2 was interesting... it was kind of a last-minute thing getting
written test arrangements made, and due to the uncertainty, I was working
on getting things set up for either a NAR or TRA cert, hoping one or the
other would be consummated: in the end, both came through, and (having
passed each writen exam) I made a flight that was observed by two NAR
witnesses and the prefect of the local TRA field, counting simultaneously
for certification by both organizations.

-dave w
Kevin OClassen - 29 Apr 2005 09:21 GMT
wow. I didn't mean to start an argument, nor did I mean to imply anything
about the methods people use for certifying L1. To each their own. For me
it's all about the "quality of experience".

I could launch any number of kit rockets, with a variety of APCP motors, and
certify. For me, not exciting enough. I've built lots of kits, I've launched
tons of rockets with engine-based time delays. A bigger engine? Ok. More
epoxy. Still essentially same-o, same-o. My goal with this project is to
build and launch a L1 rocket, incorporating as many of the requirements for
a L3 bird as is appropriate. Partly because of the complexity, partly
because of the quality of technique demanded (i.e. external disarm of pyro
charges). Partly because I believe that if something is worth doing, it's
worth overdoing.

My L1 launch will be a "peak experience", and I want it to be one to
remember (hopefully in a good way, eh?) The complexity and personal
involvement will leave me progressively more "keyed -up" until the moment of
launch. If I fail, that's cool. I promise you I will have learned a great
deal that will be incorporated in the next attempt.

I'll admit to a hidden agenda of challenging the local NAR section to grow a
bit.... I am the only member shooting hybrids, for example. Only one other
member scratch-builds most of their birds. Kits are fine, APCP is fine. Just
not enough psychological "oomph" for me.

Of course, I'm warped.

Kevin OClassen
NAR 13578
Jerry Irvine - 29 Apr 2005 14:05 GMT
> wow. I didn't mean to start an argument, nor did I mean to imply anything
> about the methods people use for certifying L1. To each their own.

My point is Phil (and like minded folks) disagrees and wants to impose
his view on those certifying, not theirs, and not the rules.

He applies this ethic in a variety of ways and a variety of places in
rocketry.

And supports and endorses others that do as well.

All to the detriment of others ocketry experience.

Jerry

Signature

Jerry Irvine, Box 1242, Claremont, California 91711 USA
Opinion, the whole thing. <mail to:01rocket@gte.net>
Please bring common sense back to rocketry administration. (too late)
Produce then publish.  http://www.usrockets.com
Ebay. http://tinyurl.com/6wlp8

Phil Stein - 30 Apr 2005 00:05 GMT
>> wow. I didn't mean to start an argument, nor did I mean to imply anything
>> about the methods people use for certifying L1. To each their own.
[quoted text clipped - 10 lines]
>
>Jerry

Look at the bright side - I have certified quite a few people and have
never refused anyone (yet)
John Bonnett - 30 Apr 2005 19:34 GMT
-----snip-----
> The MC has a bunch of useful features - not only the datalogging but you can
> use the main channel as a post apogee timer, which I am planning to do on my
> L1. Its also got the handy safety jack - you did order the 'remove before
> flight' tag, right :)

It took some scrounging around the Lab 'O Computers and PAD's before I
figured
out how to use a 'remove before flight' streamer with my RRC2.  What I
came up
with was a standard motherboard jumper to connect two wires together at
J3 for
positive power control along with an identical non-electrical plastic
jumper.  The
plastic jumper has the 'remove' flag attached via a lanyard and when
installed I
know the RRC2 is off.  At the pad I will put on the conductive jumper,
listen to the
beeps, tape it to the wires and tuck it into one of the vent holes.
Simple and
secure.

-----snip-----

> It sounds like it will be a fun cert flight - doing it in style! If I make
> that t-shirt, it will have 'The more failure modes the merrier' on the back
> I think :)

And "Real BAR's do Fault Tree Analysis" on the front :-)

John<==priming the BT this afternoon
 
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