# Thales Starstreak build

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#### BrendanH69

##### Well-Known Member
TRF Supporter
Thanks mate! I'm sure I'm over-engineering it a bit, but good to know it might help you too, Drew. If it wasn't for your spark and kick-start with this idea, I wouldn't have been inspired to run with this!

#### DrewW

##### Rocket Surgeon
TRF Supporter
Thanks mate! I'm sure I'm over-engineering it a bit, but good to know it might help you too, Drew. If it wasn't for your spark and kick-start with this idea, I wouldn't have been inspired to run with this!
I'm thrilled to see it happening, after sadly looking through more than a decade of peoples intentions to start this project. I keep on wanting to make special items for this project with my 3D printer, and keep sadly looking on as I haven't quite gotten it tweaked in just yet.

#### shockie

##### High Plains Drifter
Alright, no glue here and somewhat the "exploded view" but I put together a first mockup with a clear BT50 section at the forward end to see how things should be placed internally for adequate spacing before I start cutting or permanently attaching. Then I decided if something was going to fail it would be in the forward section anyway, so my first version will actually look remarkably similar when assembled.

View attachment 439733

Two part nosecone may perhaps need some ballast when all done, perhaps not. 12" chute packaged with wadding. I used orange tape to make the two bearings more visible. These will nominally have significantly less tape at assembly and be rigidly mounted inside the red coupler seen just aft. A hollow aluminum rod runs through both creating an axel and also a blow through path. Then will have an appropriate length of BT50 to make up the scaled length. Also, I still need to figure out routing for a kevlar shock cord...maybe I'll anchor it to the axel loosely, notch the tape and route it through? Below you can see the aft section

View attachment 439734

BT50 tube, with the aluminum rod running axially. I have an 18mm motor mount with two centering rings, but I need to make sure the ejection charge vents where I want it to so I will use the punch out of the 18mm centering ring drilled for the rod to act as a cap and a centering ring itself.

Since this was the first look at how it would go together I haven't finalized lengths yet, but plan on cutting paper and aluminum tubing tomorrow. Then prepping, gluing, and final assembly. Fins will be cut from 1/8" balsa for this pass, but I need to work on shaping/canting for appropriate rotation rates. video of initial spin test below.

View attachment 439735

Not great spinning. Needs more mass further out (radially) to maintain the rotation better, however, I'll be able to check in front of a fan when I get some canards on. I think I'll start with a 10º cant and see how well it works in a flow field.
replace the moving parts with teflon .....super slick, no friction. material will allow for faster spin up and it will stay spinned due to its low friction coefficient. I would even use ptfe power to lube it before each flight

#### BrendanH69

##### Well-Known Member
TRF Supporter
Got some progress in on the Starstreak today after yesterday's diversion into making "Spoolin' Around" (see the WDYDRWT thread).

Drilled the transition through to the top of the AV Bay coupler (the Spider bay), and then I fitted 6 M4 threaded inserts to take the M4 attachment screws. Had to shim them about 3.5mm to keep all the useable threads and keep them just under the coupler surface. Just used some cutdown plastic Mac-shims and softened them with a heat gun to form them to shape.

Removed it after it's trial fit and then bolted the Dart (Hittile) carrier to the transition, and then fitted the two back to the AV Bay coupler.

Gonna have to start thinking more about the electronics, including where to place an arming switch. I'm toying with the idea of a rotary switch fitted to the transition, or a couple of internal switches with a single pull-pin & "Remove before Flight" flag.

Next jobs on the list:
• Tip to tip F/Glass on the canards (been putting it off!).
• Get my mate to 3D print some long launch rail guides and start the Dart stacking and alignment trials.
• Fit charge wells.
• Make a few vent holes and shear pin holes.
• Spray with filler primer and start sanding.
• Make up a long harness.
• Consider making and fitting a protective metal skin to the conical base of the dart carrier - a blast deflector of sorts.

#### BrendanH69

##### Well-Known Member
TRF Supporter
Got tired of looking at the part filled spirals on the main Bus body tube, so I started filling and sealing with spray putty primer/sealer and sanding, and sanding and.....

Also did a bit of filling on the transition and I've now given it a couple of light coats of base matt black. Going to try out this Chrome-like spray paint from a local auto shop and see how it goes.

Started the first tip to tip F/Glass on the Dart canards using some fine weave 98g/sq.m cloth, so time will tell on how this goes. Humidity is just over 90% and temp is down to 20 degrees C so I'm expecting long slow cures.

#### BrendanH69

##### Well-Known Member
TRF Supporter
Time to start thinking colour schemes as I start to seal and prime. A lot depends on how the chrome-like spray paint works out. Think I'll follow this photo as my guide:
• Dart carrier (upper core)- Aluminium/silver
• Darts - Chrome
• Dart carrier lower conical section - Chrome
• Transition - Chrome.
• BUS (sustainer) body, plus the fwd/aft outer rings - White
• Fins and fin can - Aluminium grey
• Booster - as per photo below.

#### DrewW

##### Rocket Surgeon
TRF Supporter
Time to start thinking colour schemes as I start to seal and prime. A lot depends on how the chrome-like spray paint works out. Think I'll follow this photo as my guide:
• Dart carrier (upper core)- Aluminium/silver
• Darts - Chrome
• Dart carrier lower conical section - Chrome
• Transition - Chrome.
• BUS (sustainer) body, plus the fwd/aft outer rings - White
• Fins and fin can - Aluminium grey
• Booster - as per photo below.

View attachment 462502
I was wondering what you were thinking since you are very obviously going to be at that stage before me.

#### BrendanH69

##### Well-Known Member
TRF Supporter
Used a bit of watered-down carpenter's filler to do a bit of "grain" filling on the F/Glass wrapped body and fins/canards of one of my Starstreak Darts. Hope to get one ready with a protective base coat of paint on it so I can give it a test flight at this Sunday's scheduled QRS launch day.

I've got a packet of curtain rail sliders from the local DIY store and will try to modify them to make mini rail guides for the Darts. Will then use this part of the dart carrier as the launch rail for the test flight.

Made up some decorative side panels to mimic the external shape of the Dart sabot locators and the side view of the separation system. Got one epoxied on so far. A base coat of high gloss black needs to go one before the attempt at the chrome paint.

#### BrendanH69

##### Well-Known Member
TRF Supporter
First go at applying the chrome paint to the dart carrier and transition. Wasn't expecting same result as the cap, but its not too bad for these parts, especially as it will get more fingerprints and dirt as I intend to use it for a test firing of the Dart with a C6-5 at tomorrow's QRS club launch day. OR indicates I need 10g more in the nose to get it to just about 1Cal stability, with 469ft predicted.

Got a packet of curtain rail guides from the DIY store for about A$2.50 and after a little bit of trimming with the Dremel and hobby knife, they have made suitable little rail guides. Expoxied them onto the first Dart (still in its gloss black undercoat). Spoolin' Around also gets its maiden flight tomorrow on a C6-3. OR predicts 110ft. #### DrewW ##### Rocket Surgeon TRF Supporter First go at applying the chrome paint to the dart carrier and transition. Wasn't expecting same result as the cap, but its not too bad for these parts, especially as it will get more fingerprints and dirt as I intend to use it for a test firing of the Dart with a C6-5 at tomorrow's QRS club launch day. OR indicates I need 10g more in the nose to get it to just about 1Cal stability, with 469ft predicted. Got a packet of curtain rail guides from the DIY store for about A$2.50 and after a little bit of trimming with the Dremel and hobby knife, they have made suitable little rail guides. Expoxied them onto the first Dart (still in its gloss black undercoat).

Spoolin' Around also gets its maiden flight tomorrow on a C6-3. OR predicts 110ft.

View attachment 464284
View attachment 464285
Launch videos please!

#### BrendanH69

##### Well-Known Member
TRF Supporter
Launch videos please!
Interesting and reasonably successful launch day today at Cedar Grove, QLD.

Great interest in the Starstreak Dart, although RSO had concerns about it from it’s Dart Carrier mini rail (20cm long) and its probable low velocity off the rail. We discussed how to simulate a shorter rail in OR, so will look into that tonight.

As a result, I switched to a regular 1010 rail about 100cm long on a jawstand as my home made rail guides fitted it rail pretty well. So, it had it’s successful maiden flight off that with a C6-5 in it. The Micropeak altimeter reading were OK but a bit noisy on the way down. First flight reported as 315ft, quite a bit lower than the OR sim figure of 463ft.

#### Ez2cDave

##### Well-Known Member
TRF Supporter
Great interest in the Starstreak Dart, although RSO had concerns about it from it’s Dart Carrier mini rail (20cm long) and its probable low velocity off the rail. We discussed how to simulate a shorter rail in OR, so will look into that tonight.
Brendan,

When they are actually flown with the Booster, "speed off the rail" is immaterial, since they will already have velocity imparted by the Booster. At that point they are merely "upper stages" ( no "rail" required, at all, technically ).

Dave F.

#### DrewW

##### Rocket Surgeon
TRF Supporter
First flight reported as 315ft, quite a bit lower than the OR sim figure of 463ft.
Looks like you still had considerable upward velocity when your ejection charge popped. The timing of the delay is more than likely the culprit on the below projected altitude. Otherwise, looked like a very nice flight!

#### BrendanH69

##### Well-Known Member
TRF Supporter
When they are actually flown with the Booster, "speed off the rail" is immaterial, since they will already have velocity imparted by the Booster. At that point they are merely "upper stages" ( no "rail" required, at all, technically ).
Very true, Dave.
However for the first test flight yesterday, I was happy to keep the RSO happy and I was also lucky the home-made rail guides I made up the evening before were a suitable enough match for the 1010 rails available.
I did adjust the OR rail/rod length setting to 20cm in OR ( Edit>Preferences>Launch...) last night, and it appeared to have made no change at all to the velocity off the rod figure - still 12.6 m/sec.

The second flight yesterday was on one of the four longer HPR 1010 rails, which attracted a bit of fun as it was reckoned that this was the smallest rocket ever flown off that HPR rail/pad! Photo and video below, flight data to follow.

#### BrendanH69

##### Well-Known Member
TRF Supporter
Here's the graphs from the second test flight of the Starstreak Dart at the QRS launch day yesterday.

For the second test flight, I flew it with both of my Micropeak altimeters in it, plus I took the opportunity to drill two 2.9mm vent holes in the body prior to flying it. I'm convinced that one of the Micropeaks is a bit sensitive and giving more noisy readings.
Lower altitude achieved (286ft), but I'm going to partly put that down to a longer and somewhat dirtier rail than the first flight.

#### Ez2cDave

##### Well-Known Member
TRF Supporter
The second flight yesterday was on one of the four longer HPR 1010 rails, which attracted a bit of fun as it was reckoned that this was the smallest rocket ever flown off that HPR rail/pad !
Brendan,

I actually had to "look twice" to find the rocket on the rail . . . LOL !

Dave F.

#### DrewW

##### Rocket Surgeon
TRF Supporter
Alright, 3D printer is operational and cleanly printing parts without issue and also I'm freshly back from a week of vacation. Time to get back to work on this instead of playing around with the 20 other kits/scratch builds I've built this year.

I have my launch solution worked out for my partially spinning version of the dart just need a club range day to work with my schedule.

#### BrendanH69

##### Well-Known Member
TRF Supporter
I've been painting and sanding and painting!

Got all three Darts in base black gloss for now, and I'm considering buying the Spaz Stix brand of mirror chrome for them. The other chrome-like paint was OK, but more like a shiny silver, but I'm going to leave them like that. The Darts look good in black (nice contrast for launching, but perhaps that will just make them harder to find after landing.

Got the main booster body painted in gloss white, but I've not been happy with the fin colours (currently a gold colour), so going to re-do them.

Also started on finishing up the tube launcher/blip motor.

#### DrewW

##### Rocket Surgeon
TRF Supporter
Alright, pictures of prototype dart #1. The blue painters tape mid-body is there to emphasize the separation needed to allow the canard can to free rotate on the bearing assembly. Picture 2 is to emphasize that the canards have purposefully been set in with a 5º cant relative to the body axis; additionally, i've tapered on one side only to aid the clockwise rotation of the canard can. Additional canard cans will be swapped in as needed under controlled conditions to determine impact of dynamic stability on the partially spinning airframe. Considering if I should make a set with a steel BB or two set into each canard to increase the rotational moment.

#### BrendanH69

##### Well-Known Member
TRF Supporter
Did a bit more prep on the tube blip/booster motor section (seen in the first photo below on the saw horse stand) - carpenters filler, spray putty and sanding, sandin, sand...sa..........

SPAZSTIX ULTIMATE MIRROR CHROME paint ordered and on it's way for the Darts. I'm shelling out big time for this (A\$62 for two small 3.5 Fl.oz. spray cans), so it better be as good as the youtube videos show!

Don't like the gold colour of the fins, so I'm going to try one more - Dupli-colour Tungsten pearl metallic auto paint.

Couple of pictures of the general assembly taking shape (minus electronics):

#### BrendanH69

##### Well-Known Member
TRF Supporter
Got two coats of white gloss onto the booster/blip section yesterday, so took a chance to pose with the (almost complete) assembly!
Hope to re-spray the fins later today, and then spray the chrome parts of the booster/blip section later in the week.

#### DrewW

##### Rocket Surgeon
TRF Supporter
3D printer ran overnight to print the first segment of my prototype Starstreak booster tower (Picture below). This lovely shade of PLA just happened to be loaded in the printer at the time I kicked it off. This lower segment printed just fine but the tower section had some issues so I'm having to reprint. First pass doesn't include the dart supports or dart rails, but will make adjustments on the next pass after making some measurements. Current booster build is a 93% scale.

#### Nytrunner

##### Pop lugs, not drugs
TRF Supporter
How does the booster factor into the stability during boost of the 1st stage? (i feel like I messed that from earlier in the thread)

It's looking great!

#### Lemmiwinks

##### Member
Really interesting. Would like to see a version with the darts powered by A10T size engines.

#### DrewW

##### Rocket Surgeon
TRF Supporter
Alright, first print of low fidelity tower is complete and I see some areas that need modifications for a flightworthy version...though I may take this one out for a test launch using static darts to get an idea of drag.

Image shows 93% booster next to 109% dart...a little mismatched.

#### BrendanH69

##### Well-Known Member
TRF Supporter
Alright, first print of low fidelity tower is complete and I see some areas that need modifications for a flightworthy version...though I may take this one out for a test launch using static darts to get an idea of drag.

Image shows 93% booster next to 109% dart...a little mismatched.
Hi Drew, the main body tube looks like it's a really nice quality one and will hopefully prove easy to seal and paint. Mine was a bit low grade and "furry", which made it harder (and more coats) to seal and paint.
What size is it? Can you get the next size up to match your scales more evenly?

3D print looks so good, and I can't wait to see your final version with the rails etc. - I'm officially jealous!

#### DrewW

##### Rocket Surgeon
TRF Supporter
Hi Drew, the main body tube looks like it's a really nice quality one and will hopefully prove easy to seal and paint. Mine was a bit low grade and "furry", which made it harder (and more coats) to seal and paint.
What size is it? Can you get the next size up to match your scales more evenly?

3D print looks so good, and I can't wait to see your final version with the rails etc. - I'm officially jealous!
@BrendanH69 Tubes were free! Courtesy of some friends at work who know I’m in to rocketry. 105mm OD I have eight of them sitting around and this seemed like a good project for them. No fuzz, and very shallow spirals.

I’m looking at options for the next tube size larger, but very few choices short of wrapping my own or buying 25. I’m leaning towards wrapping my own to at least learn a new skill.

Speaking of jealous, yours looks great and ready to fly! I’m still quite a ways off from that.

#### BrendanH69

##### Well-Known Member
TRF Supporter
Built a little stand to hold the upper assembly of the Darts + Dart Carrier + Fwd Transition + AV Bay while I prep it or work on it. Just used various off-cuts from earlier in the project.

Added cut-down bolts into the rail guides to act as aft stops for the Darts to sit back on and hold them in position during launch.

For test flights with the Darts in place, I don't want one or more Darts coming in ballistic after deployment of the Nose/Carrier/AV Bay. So, I made up a little retention system that basically pins the Darts by their rail guides tightly back onto their aft stop. Comprised of a red G10 F/Glass disc under the carrier fwd "nose cone" and three cut-down bamboo chop-sticks inserted into the top of the rails.

#### BrendanH69

##### Well-Known Member
TRF Supporter
Drew...thinking of safety, time to think about other necessary fight and public safety features we might need to design/build.

Doing the above Dart retainer work has had me thinking ahead about one of the worse case flight safety scenarios..... 3 Darts coming in ballistic, with or without their B6 motors initiated.

In my mind, the flight mission I want to progress towards first is to rail-launch the Starstreak main Bus and the Dart Carrier assembly with active 3 Darts that are then ignited simultaneously and mid-air launched at a pre-determined time or altitude as the Bus coasts and before it's apogee. I want to do all that at a reasonable altitude for visibility (show!) and safe recovery, so I'm targeting the Bus to about 500ft apogee and Darts under 1000ft apogee.
Later missions will try to add the booster/Blip motor and maybe tube launching into the equation.

For safety, the avionics for initiating the three Dart ignitors will need to incorporate a switch/logic feature to ensure the Darts are not ignited if the Bus and Carrier are more than a safety critical angle away from vertical. For this purpose I'm planning on using the Simple-Timer-for-Staging from Apogee which has that type of protection if the Bus ventures more than 45degress from vertical.

However, if the Starstreak does venture more than 45degress from vertical, then the Darts will not be launched, will not ignite and will never be able to deploy their own parachutes after they fall/get flung out of their rails when the whole fwd Carrier/Transition/Av Bay assembly is deployed away from the Bus and dangles under the main parachute.
Suddenly all three Darts are potentially hurtling earthward!

How do we manage this risk? Thoughts?

One idea I've had today would be to have a similar fwd carrier nose and Dart retainer assembly as I've made today, but epoxy it all together and modify the central carrier tube to make this retainer assembly "deployable" with its own BP charge but held in with a shear pin or two.
As a complete "carrier nose cone and Dart retainer assembly" with shear pins strong enough to stay in place (and therefore stop the Darts falling out in this scenario during main deployment and descent), it would require a fourth ignitor, a small BP charge capability and would be initiated at the same time as the three Darts.
Downsides/issues I can see with this deployable "carrier nose cone and Dart retainer assembly" are:
• It would very, very likely impact and damage several of the Dart canards.
• Timing and sequence are likely to be an issue, especially if triggered from the same "Simple Timer" unit.
The real thing uses shear pins to retain/release the Darts, with the deployment/shearing action being done by some sort of piston action after the burn out of the Bus motor, and then the 30Hz spin action does most of the separation, although they might also get a little kick from the piston too. See the earlier posts with the Royal Ordnance videos.

#### DrewW

##### Rocket Surgeon
TRF Supporter
Drew...thinking of safety, time to think about other necessary fight and public safety features we might need to design/build.
@BrendanH69 You raise some good points I've spent some time thinking about also. Something that is likely to happen for this design no matter what is drag separation. This is actually how the darts deploy on the live system; more than likely, between 0.1-1.0s (estimated) after bus motor burnout the darts will separate unless retained. The good news here is that if you do a retained flight like you have planned in post #148 you can get a sense of the timing for time to apogee (better yet if you can measure it). As long as that time is >1 second your darts will be clear of the body before apogee where the bus will nose-over, thankfully aerodynamics keep it from doing this earlier.

My thoughts: (1) do a launch with retained darts for overall timing burnout to apogee; (2) an unpowered and unrestrained dart launch with a streamer on a leash out the aft (never seen it, but seems like it could work) to verify the drag separation timing; (3) using information from 1 & 2 you should be able to conduct a safe powered dart flight with a timer based ignition; alternatively, you could use accelerometers to measure thrust and ignite darts at burnout +0.1s.

I think the angle lock-out is prudent but not absolutely necessary. If you're fast off the rail, and winds are reasonable there shouldn't be any reason for unsafe flight. Then again, nobody wants to do a duck and cover at a launch event.

Drew