"Starship" - L3 Build Thread

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Update #26

I tested the ejection charges today. I went with 2g for the drogue and 1g for the main. More testing will be done in two week, probably will increase the main charge.

Video:
 
I've heard that the main is just supposed to get the nosecone off since the nosecone will pull the parachute out of the payload bay. I'll probably increase it to 1.5g and see the results, but I think 1g would work great for flight.
Looked kind of underpowered for the main, but I don't have that mich knowledge.
 
I've heard that the main is just supposed to get the nosecone off since the nosecone will pull the parachute out of the payload bay. I'll probably increase it to 1.5g and see the results, but I think 1g would work great for flight.

I think that is a dangerous generalization. Is it possible for the nose to pull out the rest of the laundry, maybe, depends on how tight its packed and how much other volume you have in the chamber in question.

IMO, retest at 2 grams for the main.
 
I think that is a dangerous generalization. Is it possible for the nose to pull out the rest of the laundry, maybe, depends on how tight its packed and how much other volume you have in the chamber in question.

IMO, retest at 2 grams for the main.

I pulled on the nosecone with maybe a few pounds of force and the parachute slid right out after the test. What stopped it from coming out was the nosecone hitting the grass. I'm confident that it would have smoothly deployed. But I am going to test again with 1.5g as 2g is way overkill for the very small payload bay volume. The backup charge will be 150% of the final main amount I decide on, likely 1.5 or 2g.
 
I know the general rule of thumb is that it's better to push a parachute out than to pull it. Maybe that rule or this situation carries subtleties that I'm not aware of.
 
I know the general rule of thumb is that it's better to push a parachute out than to pull it. Maybe that rule or this situation carries subtleties that I'm not aware of.
It seems like the gas just went around the parachute and popped the nosecone off. I'll test with 1.5g next weekend and see if it has similar results, but I'm nearly 100% confident that it would have deployed reliably with only 1g. In addition, I have a backup charge to ensure the safe deployment of the main in case the flight does not go as tested.

The calculator gives 1g as a bit over 10psi with 3 shear pins which is good. 2g would be over 20psi, which is dangerous in itself. 1.5 produces the upper end of the PSI range with 15psi, I'll have to test it to see if it's too much.

The payload bay is only 4in x 15in with the parachute taking up 80% of the space. It has 3 shear pins for the nosecone.
 
I use 1.4g in my 4" MC SDX3 with 2 2-56 nylon pins. I looked at my L2 flight data and the main was set for 500' and drogue decent rate was 45f/s. Main fired right on time but the air frame fell another 100' in about 2 seconds to get everything in line and slowed down to a slow 11f/s. Yes its good the nose cone came off, there is a chance the main would rattle out but that takes time, then it needs to inflate and slow the air frame down.

~John
 
I use 1.4g in my 4" MC SDX3 with 2 2-56 nylon pins. I looked at my L2 flight data and the main was set for 500' and drogue decent rate was 45f/s. Main fired right on time but the air frame fell another 100' in about 2 seconds to get everything in line and slowed down to a slow 11f/s. Yes its good the nose cone came off, there is a chance the main would rattle out but that takes time, then it needs to inflate and slow the air frame down.

~John
My main is set at 900 with backup at 700 for the first flight. Depending on the results the main might be lowered to 700 and the backup at 500. This gives it time to fully open and settle. I'll test with 1.5g but will probably reduce the main charge to around 1.2-1.3g with the backup at 2g.
 
Update #27

Successful launch!

Launched Starship for the first time today.

Main: 1.2g, 1.5g backup (900ft for main, 700ft for backup)
Drogue: 2g, 2.2g backup (1 second delay for backup)
Parachutes: 9ft main, 2ft drogue
Motor: K535W

All charges were set off by the dual Stratologger CFs set with full redundancy. Everything went flawlessly besides a tangled booster which will be easily fixed by moving the swivel.

Video of launch:

Pictures: Shown below.VideoCapture_20191109-231245.jpeg1573350480264_13thPic00005.jpeg13thPic00014.jpeg13thPic00015.jpegIMG_20191109_143303.jpegIMG_20191109_143343.jpegIMG_20191109_143409.jpegIMG_20191109_143418.jpeg
 
Looks like it was a great day. I’m sorry I missed the launch. Hoping the weather is as nice in December.
It was a beautiful day. Perfect day to launch as the weather was great and best of all, no wind! You were attending something a "bit" more important. Hope to see you next month if the weather is nice!
 
Impressive project. Based on some of the decisions you discussed in this thread (not launching in poor wind, and ground testing deploy charges), I think you have a bright future in rocketry and whatever career path you choose.
 
Long time no see! Planning to get back into rocketry and resume this project / quest towards L3. I think the logical steps would be to get back into launching with a smaller motor (like the K used in the test flight) then moving onto good sized L motors to get a flight profile similar to a baby M. Excited to get back into this hobby, will keep you guys updated!
 
Welcome back. What kept you? ;)

Why the L motor flight? I can understand repeating the K flight if you feel like you're rusty and to check the rocket for "rattles". But then why launch on a full L then a baby M, and not just go right to the M?
 
Welcome back. What kept you? ;)

Why the L motor flight? I can understand repeating the K flight if you feel like you're rusty and to check the rocket for "rattles". But then why launch on a full L then a baby M, and not just go right to the M?

Transferring schools/states has kept me busy the last 2 years, starting to get really settled in now and getting back into the hobbies I was into. Repeating the K is certainly a good idea, it's just the L/M that is a bit conflicting for me. I know the L3 is very complicated compared to L1/L2 and will take me a while to get all the paperwork hopefully situated and get in contact with people in my area who can oversee my attempt. I know that L3 rockets normally have to be all laid out and approved before being made, not sure how this would work if I made this rocket to practice L2 more before my L3 so it's already produced. Thankfully I have the build very well documented so that might help me out there. NAR's Level 3 Certification Package looks like it includes a build section so I would assume an already built rocket with the documentation I have would be perfectly acceptable. Just need to get in contact with experienced individuals in my area and see what my best course of action would be to hopefully be able to use this rocket as my L3 attempt. Launching on a full L would closely replicate the flight of the baby M and make sure the rocket is up to the task, but as you say, why not just try it on the actual M?

Hopefully, I can get this all figured out. If there are any L3 TAP members or L3CC members reading this feel free to reply and help clarify some things, would greatly appreciate it.
 
I am decidedly not an L3 TAP or L3CC member, but I'd suggest that putting your new L3 overseers in touch with your former ones, who observed the design and construction, couldn't hurt.

Based on the reasoning above, I would skip the L launch. The K launch should serve as a good shake-down flight for you and the rocket both. After that, I would think, the L flight is just one extra opportunity for something out of your control to go wrong. Rehearse once then go for it!
 
Long time no see! Planning to get back into rocketry and resume this project / quest towards L3. I think the logical steps would be to get back into launching with a smaller motor (like the K used in the test flight) then moving onto good sized L motors to get a flight profile similar to a baby M. Excited to get back into this hobby, will keep you guys updated!
That’s a very reasonable plan and will allow you to build confidence as well. If you need help finding an L3CC or TAP near you let me know and I can help you find someone.
 
That’s a very reasonable plan and will allow you to build confidence as well. If you need help finding an L3CC or TAP near you let me know and I can help you find someone.
Thanks for the reply Steve! Are you familiar with if a rocket that is already built but is documented still qualifies for a L3 attempt? I did not get it approved by a TAP / L3CC before making it as I originally only planned on using it for L2 experience. I would be more than willing to go back and do all the paperwork as if I haven't built it yet. I'll message you about finding an L3CC/TAP near me.
 
Transferring schools/states has kept me busy the last 2 years, starting to get really settled in now and getting back into the hobbies I was into. Repeating the K is certainly a good idea, it's just the L/M that is a bit conflicting for me. I know the L3 is very complicated compared to L1/L2 and will take me a while to get all the paperwork hopefully situated and get in contact with people in my area who can oversee my attempt. I know that L3 rockets normally have to be all laid out and approved before being made, not sure how this would work if I made this rocket to practice L2 more before my L3 so it's already produced. Thankfully I have the build very well documented so that might help me out there. NAR's Level 3 Certification Package looks like it includes a build section so I would assume an already built rocket with the documentation I have would be perfectly acceptable. Just need to get in contact with experienced individuals in my area and see what my best course of action would be to hopefully be able to use this rocket as my L3 attempt. Launching on a full L would closely replicate the flight of the baby M and make sure the rocket is up to the task, but as you say, why not just try it on the actual M?

Hopefully, I can get this all figured out. If there are any L3 TAP members or L3CC members reading this feel free to reply and help clarify some things, would greatly appreciate it.
I just went back and skimmed the thread. It looks as though you started the build (and completed it?) without ever discussing it with a TAP or L3CC. Both NAR and Tripoli require that you submit the design to a TAP or L3CC and get approval before beginning construction. Tripoli used to allow a person to simply use a rocket that had previously flown but no longer does. That change came about shortly before you started this build thread as I recall. The requirement is stated on the Tripoli certification page for L3.
 
Thanks for the reply Steve! Are you familiar with if a rocket that is already built but is documented still qualifies for a L3 attempt? I did not get it approved by a TAP / L3CC before making it as I originally only planned on using it for L2 experience. I would be more than willing to go back and do all the paperwork as if I haven't built it yet. I'll message you about finding an L3CC/TAP near me.
Looks like I answered this while you were asking. I’ll watch for your PM.
 
Well that's a bummer. I remember the Tripoli rule of being able to use a rocket that has previously flown and was hoping that was still the case. Suppose the best way of going about it would be making a new rocket from scratch after approval from a TAP/L3CC. Kind of a shame that I would have 2 rockets of similar capabilities but I suppose that I could just make the new one bigger haha.
 
I was working off the assumption of current rules - and compliance thereto. I assumed you had the design approved before starting construction, as I hadn't registered that this is reuse of your L2 rocket. So the thinking was that if you had to change TAP tams mid stream you could get the first team to discuss the design/construction approval with the second team and be OK. But that obviously is not the case.

Well, back you go to the drawing board. Do you "have to" start over, or "get to"?
 
I was working off the assumption of current rules - and compliance thereto. I assumed you had the design approved before starting construction, as I hadn't registered that this is reuse of your L2 rocket. So the thinking was that if you had to change TAP tams mid stream you could get the first team to discuss the design/construction approval with the second team and be OK. But that obviously is not the case.

Well, back you go to the drawing board. Do you "have to" start over, or "get to"?

I did not think to have the design approved at the time as at the time, I could have it approved for my L3 attempt after gaining L2 experience with it. The rules now are you must get the design approved before manufacturing it so this rocket can just be used to gain L2 experience which is still very useful. Looking forward to designing my L3 attempt and getting in contact with local members to get it approved correctly this time. I assume that using recovery hardware/electronics from this rocket would be perfectly fine but I'll double check with them. Should be a fun project to get back into the hobby.
 
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