L3 Cert - 1/2 scale Patriot

Discussions for scratch builders. For the enthusiast that builds from the ground up. Tell us what you've built and what projects you working on in the space race.

Moderator: Moderators

User avatar
CATO
Mr Smiley
Mr Smiley
Posts: 1855
Joined: Thu Dec 24, 2009 6:20 pm
Location: Sydney, NSW
Contact:

L3 Cert - 1/2 scale Patriot

Postby CATO » Sun Feb 03, 2013 9:20 am

Hi all,

Thinking about building a 1/2 scale Patriot for my L3 cert attempt. This will be a copy of Mr David Greenapple's model and I have his permission to replicate this model. The model has an inboard 75mm mmt and 4 outboard 38mm mmts. The cert flight will be on a single M1315 or CTI equivalent and utilise a 3 tube dual deployment method. The airframe will be full fibreglass and home rolled (thanks Nic). Once I succesfully complete the L3 flight :D , I will utilise the outboard motors, either ground or air start via a Clust-O-Matic http://www.whooshtronics.com/products-t110/clust-o-matic.aspx and or a Tiltometer http://www.rocketiltometer.com/pages/The-RockeTiltometer.html. Dual electronics, RDF, BRB900 GPS Telemetry, etc, etc.

Any recommendations?
Half_Scale_Patriot.png
Half_Scale_Patriot.png (61.07 KiB) Viewed 9048 times

DG_Half_Scale_Patriot.jpg


Level 3 TAP Submission Document (this is a very usefull document) and Rocksim File can be found at
http://www.astralisrocketry.com/Knowledge_2.html
"In thrust we trust"

AMRS 21 L3

Impulse:
2017: 5,973 Ns (13.14% M)
Ns 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: 1.14M

User avatar
Scoop1261
L3 Rocket GURU
L3 Rocket GURU
Posts: 1924
Joined: Sun May 06, 2007 9:29 pm
Location: Perth, Western Australia
Contact:

Re: L3 Cert - 1/2 scale Patriot

Postby Scoop1261 » Sun Feb 03, 2013 9:38 am

CATO wrote:
Any recommendations?


Make sure you bribe your TAPS with booze! :D
Why Limit Yourself?

AMRS #4 - L3 |TRA #11080 - L3 |MDRA #263

Impulse: A Whole Lot ..So much I've lost count!

User avatar
CATO
Mr Smiley
Mr Smiley
Posts: 1855
Joined: Thu Dec 24, 2009 6:20 pm
Location: Sydney, NSW
Contact:

Re: L3 Cert - 1/2 scale Patriot

Postby CATO » Sun Feb 03, 2013 9:55 am

Done.... :D
"In thrust we trust"

AMRS 21 L3

Impulse:
2017: 5,973 Ns (13.14% M)
Ns 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: 1.14M

User avatar
kopius
Elle3
Elle3
Posts: 2793
Joined: Mon Apr 23, 2007 4:30 pm
Location: Gold Coast, Queensland
Contact:

L3 Cert - 1/2 scale Patriot

Postby kopius » Sun Feb 03, 2013 11:13 am

LOTS OF BOOZE is what I think Scoop was trying to say ;-)
QRS Secretary

AMRS #3 L3 ACO
Life member of QRS

NAR L2 #98260

MDRA Member #0241

User avatar
cryoscum
STOP... Hammer Time The Prodigy
STOP... Hammer Time    The Prodigy
Posts: 1802
Joined: Wed Oct 06, 2010 2:54 pm
Location: QLD, NSW & VIC

Re: L3 Cert - 1/2 scale Patriot

Postby cryoscum » Sun Feb 03, 2013 3:30 pm

Yeah, I can confirm the efficacy of this approach! :lol:
AMRS L3 | NAR L3 | QRS 089 | MDRA 224
AMRS Technical Advisory Group

Total impulse for 2016: 32,458 Ns (thus far)
Total impulse for 2015: 84,231 Ns
Total impulse for 2014: 40,757 Ns
Total impulse for 2013: 62,927 Ns

User avatar
CATO
Mr Smiley
Mr Smiley
Posts: 1855
Joined: Thu Dec 24, 2009 6:20 pm
Location: Sydney, NSW
Contact:

Re: L3 Cert - 1/2 scale Patriot

Postby CATO » Sat May 04, 2013 9:40 pm

OK....

Given I have received no negative posts thus far from our friendly TAPS, I will hopefully start this build in the next few weeks, the build will take months not weeks. The rocket will be fully scratch build except for the NC which will be a PML FNC-7.5 Fiberglass Nosecone.

The only changes to this existing successful design is an extension to the fin frame section from 30" to 32" (plus coupling tube) to accommodate CTI motors, and 4 ignitor / e-match tubes, not 1.

1.png
1.png (11.46 KiB) Viewed 8905 times

MMT_75mm_x1_32mm_x4_DG.png
MMT_75mm_x1_32mm_x4_DG.png (200.89 KiB) Viewed 8905 times
"In thrust we trust"

AMRS 21 L3

Impulse:
2017: 5,973 Ns (13.14% M)
Ns 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: 1.14M

User avatar
CATO
Mr Smiley
Mr Smiley
Posts: 1855
Joined: Thu Dec 24, 2009 6:20 pm
Location: Sydney, NSW
Contact:

Re: L3 Cert - 1/2 scale Patriot

Postby CATO » Sun Jun 16, 2013 4:12 pm

Three 7.5" airframe tubes rolled (1 spare just in case), and ready for the smoker...

Post cure will be:
15 hours at 50*C
4 hours at 70*C

3_7.5_Inch_Tubes.jpg
"In thrust we trust"

AMRS 21 L3

Impulse:
2017: 5,973 Ns (13.14% M)
Ns 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: 1.14M

User avatar
cryoscum
STOP... Hammer Time The Prodigy
STOP... Hammer Time    The Prodigy
Posts: 1802
Joined: Wed Oct 06, 2010 2:54 pm
Location: QLD, NSW & VIC

Re: L3 Cert - 1/2 scale Patriot

Postby cryoscum » Sun Jun 16, 2013 4:20 pm

Yeah, baby! :lol:
AMRS L3 | NAR L3 | QRS 089 | MDRA 224
AMRS Technical Advisory Group

Total impulse for 2016: 32,458 Ns (thus far)
Total impulse for 2015: 84,231 Ns
Total impulse for 2014: 40,757 Ns
Total impulse for 2013: 62,927 Ns

BerowraRocketBoy
Rocket Flyer
Rocket Flyer
Posts: 194
Joined: Fri Jan 18, 2013 7:59 pm
Location: Berowra Heights, Northern Sydney

Re: L3 Cert - 1/2 scale Patriot

Postby BerowraRocketBoy » Sun Jun 16, 2013 7:05 pm

Nice work!

Nic, looks like you've got some competition!
MPR cert: Grey Dot on an F52-8T

Level 1 cert: Ok... so maybe I was a little optimistic putting this in. But if I do do it, then it'll be something fast.

User avatar
CATO
Mr Smiley
Mr Smiley
Posts: 1855
Joined: Thu Dec 24, 2009 6:20 pm
Location: Sydney, NSW
Contact:

Re: L3 Cert - 1/2 scale Patriot

Postby CATO » Sun Jun 16, 2013 7:27 pm

BerowraRocketBoy wrote:Nice work!

Nic, looks like you've got some competition!


Cheers BerowraRocketBoy, the majority of everything I know about glassing has been learnt (copied) from Nic...
"In thrust we trust"

AMRS 21 L3

Impulse:
2017: 5,973 Ns (13.14% M)
Ns 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: 1.14M

PJR
Rocket Crew
Rocket Crew
Posts: 267
Joined: Fri Jul 13, 2012 7:37 pm
Location: Albion Park/Wollongong

Re: L3 Cert - 1/2 scale Patriot

Postby PJR » Sun Jun 16, 2013 7:54 pm

David looks very good. What wall thinkness did you end up with

Phil

User avatar
kopius
Elle3
Elle3
Posts: 2793
Joined: Mon Apr 23, 2007 4:30 pm
Location: Gold Coast, Queensland
Contact:

L3 Cert - 1/2 scale Patriot

Postby kopius » Sun Jun 16, 2013 8:04 pm

Very nice David.

Whilst your TAPs are OK with your ideas, before getting too far into any assembly, please submit your initial documentation for review
QRS Secretary

AMRS #3 L3 ACO
Life member of QRS

NAR L2 #98260

MDRA Member #0241

PJR
Rocket Crew
Rocket Crew
Posts: 267
Joined: Fri Jul 13, 2012 7:37 pm
Location: Albion Park/Wollongong

Re: L3 Cert - 1/2 scale Patriot

Postby PJR » Sun Jun 16, 2013 9:45 pm

David my second question, your AV bay is 12 inch long? if the centre section is 2" that leaves 5" (127mm) each side to join your upper airframe and mid airframe. Is that enough support for the tubes in that size of a diameter? Just asking as I have made my shoulders 190mm for a 6" diameter tube

Phil

User avatar
CATO
Mr Smiley
Mr Smiley
Posts: 1855
Joined: Thu Dec 24, 2009 6:20 pm
Location: Sydney, NSW
Contact:

Re: L3 Cert - 1/2 scale Patriot

Postby CATO » Mon Jun 17, 2013 12:17 am

PJR wrote:David my second question, your AV bay is 12 inch long? if the centre section is 2" that leaves 5" (127mm) each side to join your upper airframe and mid airframe. Is that enough support for the tubes in that size of a diameter? Just asking as I have made my shoulders 190mm for a 6" diameter tube

Phil

Hi Phil,

The tubes are @ 2.5mm thick.

These are images from a 1/2 Scale Patriot that has already flown on an M powered motor for a successful L3 cert, this airframe was made from PML " Pre-Glassed Phenolic Airframe Tubing - FGPT-7.5" and phenolic couplers.

In relation to determining the Coupler Length for HPR rockets, there are a number of theory's / considerations out there, 2 x dia, 1.5 x dia, 1 x dia, dual wall coupler, coupler material, super sonic, sub sonic, etc, etc, etc.

A number of rocket manufactures supply 6" couplers for a 4" airframe (3" per side).

My couplers will be dual walled, fiberglass (3mm thick each wall), and the rocket will reach .8 Mach "TOPS".

The majority of coupler failures are between the fin-frame and the mid-frame, my coupler at this junction will be a dual layer fibreglass 12" coupler, 6" each side of the junction.


I will rely on the TAPs (2) :) , and others providing recommendations.
"In thrust we trust"

AMRS 21 L3

Impulse:
2017: 5,973 Ns (13.14% M)
Ns 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: 1.14M

User avatar
CATO
Mr Smiley
Mr Smiley
Posts: 1855
Joined: Thu Dec 24, 2009 6:20 pm
Location: Sydney, NSW
Contact:

Re: L3 Cert - 1/2 scale Patriot

Postby CATO » Mon Jun 17, 2013 7:40 am

Phil, forgot to also mention that my av bays will also be reinforced with 4 x M5 or M6 stainless steel threaded rods.
"In thrust we trust"

AMRS 21 L3

Impulse:
2017: 5,973 Ns (13.14% M)
Ns 16: 34,558; 15: 35,955; 14: 6,016; 13: 10,208
PB - Gorilla N2717WC, H: 10,260', S: 1.14M


Return to “Scratch Built”

Who is online

Users browsing this forum: No registered users and 4 guests