Vogon Poetry - 2 stage - old thread

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Oh man....that list just gives me goosebumps. I've been living vicariously through this thread for months. This is going to be so awesome. Good luck!
 
shaving doors... we are delayed coz boss man is shaving doors...

must not like hairy doors!
 
Story so far... Pete turned up at my house at 10pm... instead of 3pm... so.. off we went.
The weather just north of Crater lake was 27 degrees with freezing fog, slow going. Then the truck in front of us hit a large deer, which then lay in the road, steaming, and we noticed it about 40 yards away. I managed to swerve and we only clipped it. The front and side of the RV and truck now have CSI blood splatter. Got to the KFalls KOA at 4:16.... Pete collapsed into his sofa bed and I went through to collapse in mine. Only to find that during the torrential rain of the last couple of days, I have a leak... my bedding and pillows were soaked. Wrapped myself up in my Carhart jacket and a load of towels and tried to get to sleep.

8am the alarm goes off... no sleep.
Luckily the KOA has a laundry room, 2 hours later, I have dry bedding. I can dry the bed on the playa... its dry out there, open all the windows and turn the heater on.

We got to Gerlach 3pm and the weather wasnt too good. A little rain. Stopped at Brunos gas station, filled with diesel, then off to Brunos for food. NO RAVIOLI.... non left today... so I had to eat the double chilli cheeseburger! OMG that was one of the best burgers I have had in a long time, at a real reasonable price.... wrapped up by a cute waitress!

Talked to a couple of people who has been out to the playa, there is a little mud at the 12 mile entrance which had confused the portapot people, who then turned around and went back to Fernley!

We headed out to the entrance, and yes, there was a little mud. I gunned the throttle on the Chevy ... and lost the rear end of the trailer... did a nice little half spin, recovered, and we giggled for the next 5 mins as we headed out onto the flat.

Now on the flight line, we managed to camp next to the Hillybilly crew, so we have a guaranteed fun weekend no matter the weather.
We are expecting about 12 people in our Numb Camp by midday tomorrow.

There was already about 3 dozen RV's on the flight line, guess at nearly 100 people... and its only Thursday.

The rest of the numblettes are outside socializing... i am tired.

Tomorrow looks like a little rain with clouds, so i would say no to that.
Saturday looks good... Sunday morn better.... since we need to leave camp midday Sunday at the LATEST... I am gunning for Saturday morn.

If the internet holds up, (Hotspot with 3G and 3 bars), then I will update more over the weekend.
 
Good luck for today! Hope it goes more smoothly than the start of the trip did!
 
I've been thinking about you guys this morning. I'm not sure if I am envious of you or scared for you. Probably equal parts of the two. Best of luck and let us know how it goes ASAP!
 
Scrubbed - for multiple reasons...
This has been the year of the two stage at BALLS.... and the year of the two stage carnage!
Fuller update later
 
making a long story short... electronics problem.

I wasted a lot of Friday morning wandering up and down the flight line taking in all the people and wonderful selection of projects, lending a hand a few times if people needed an extra. Everyone was very friendly and had no problems sharing their projects details, motor design, pets name, etc.. :smile:

I got the booster motor built and in the rocket, tested the tracking, etc... fine, and started on the sustainer, to realise that i hadnt quite finished as much as I thought I had. I had the wires in place, etc, but hadnt put some JB weld around the holes to protect, etc., I needed to wait for RTV to set on something else, etc. and was obviously seeming a little frazzled as a few other team members brought me drinks, snacks, etc and told me there was no rush, and take my time. I took it one step at a time, wandering and watching between. The atmosphere was fantastic.
Kept working on it until the waiver closed... ho hum... finish it tomorrow.

I kept plodding through things on Saturday, but bigger and bigger things were launching and I had to watch, or go and find out what the outcome was of flights that I was real interested in.
Mid afternoon Pete flew one of the Team Numb N motors in a minimum diameter beastie to 27,000 ft... popped the main at apogee and went for a 4.5 mile drive. He had forgotten his tracking handset, but the TeleGPS was transmitting from his rocket. I had my HT and was decoding packets and we had GPS!!
Took quite a few hours out to take in the Party, and various dinners and offerings of other camps. A full O motor in the burn pit was a unreal experience from 30ft away!! I will need to see when that gets on YouTube!
Some of our camp wanted to go off to Frog Pond, and I went back into my RV to finish. At some point over the evening I had learnt that there was an update to the TeleMetrum / TeleMega firmware which fixed some problem with Kalman filter exitting Mach transition or something, so i spent a long time downloading over the phone hotspot and flashing all my units..... only to find out that I couldnt get sustainer continuity on the sustainer motor light channel. This and a GUI issue on my lower res laptop which meant I couldnt commit any changes to the altimeter.

Packed in an got some sleep..

Sunday, helped a few Team Members prep for their L3, one successful, one very nearly...
During the first few hours we watched 4 two stages, one after another boost nicely, then fail to light sustainer and come in hot. I announced after the 4th that I wasnt going to fly. I had about half dozen hands on my back almost immediately telling me i made the right choice.

Spent the rest of the morn watching rockets! Packed up camp and we hit the 'trail' at 2:16pm

514 miles later, 2:15am, I rolled into my driveway. Pete unloaded his stuff and headed off to his house.

1- Dont Trust Google . it does NOT know how much two people can fit in a 2500HD and 26ft trailer.
2- Max Axle weights are a recommendation only on trips like this.
3- That dust doesnt come off ... over 500miles later and driving through two rainstorms... the stuff is still clinging on there...
4- A camp cook is worth his weight in ... erm...
5- You will NOT go hungry at BALLS!
6- You will NOT go thirsty at BALLS!
7- The rocket is never really and truly finished.
8- DO NOT FLASH YOUR HARDWARE ONSITE.... i have been in the business long enough... stupid me..
9- When you hear that voice on the shoulder ... listen to it.
10- ITS BALLS BABY!


Loved every minute... people were fantastic crowd... there is always next year!

now... hmm... 5 grain in the booster simmed at 117K ... hmm..


Thank you to EVERYONE!

this is not finished yet!

pics will follow
 
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Sorry to hear you had prep troubles. You made the right call. That's the main reason I scrub even driving out for the launch. If I don't have everything but the charges ready at least one day in advance to me leaving the driveway I scrub the launch. I don't like the stress of prepping onsite, especially if there is call in waiver windows. It gives me a real bad feeling inside, like I'm forgetting something because I get distracted every five minutes. I need full confidence before loading it.
 
OK.... and it resumes :facepalm:

After a few days of decompress..... what do I want to do with this.

Answer - I want to hit 100K, pure and simple. I had no idea, nor inclination, at the start of this build to have that as a goal, it was 50K, but, now it is a challenge :)

Update to personal goals
1) 100K
2) as high as I can possibly go with M to M

81K (sim) is nice, but, if I am hitting that high with this 'throw together' build, a few tweaks and I really do believe that we could get a 100K flight, getting a setup that sims to 120K would get us enough 'wiggle room' that 100K may be do-able.
This is going to become very difficult, very quickly!

Break this down into two parts - sustainer and booster

I think that the sustainer is about as good as I could want, and has probably the best motor for the job, the CTi M840.
The booster.. Start off, we are running a 4 grain, the M1830. I KNOW that I can fit a 5 grain CTi case in the booster with no problem at all, but I don't think that will give me enough ooompfh. I believe we need a full 6 grain.

The other thing I noticed over the weekend is that quite a lot of the 2 stages that had three fins on the booster started to corkscrew a second or two into the flight. I have no idea why.. but.. if I need to build another booster stage, then I am definately looking at a 4 fin booster.
 
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The other thing I noticed over the weekend is that quite a lot of the 2 stages that had three fins on the booster started to corkscrew a second or two into the flight. I have no idea why.. but.. if I need to build another booster stage, then I am definately looking at a 4 fin booster.

This is known as coning (or inertia coupling) and can be caused by a variety of factors such as off-center motor cores, or off-axis mass in the rocket. I suspect many of the sustainers you saw were flying on longburn or moonburner motors, which often have a c-slot or moonburner grain geometry. This can lead to thrust asymmetry, which can then lead to coning. Four fins can help eliminate coning to a degree, but it's still something to design for and consider, especially if you're flying a longburn motor.
 
This is known as coning (or inertia coupling) and can be caused by a variety of factors such as off-center motor cores, or off-axis mass in the rocket. I suspect many of the sustainers you saw were flying on longburn or moonburner motors, which often have a c-slot or moonburner grain geometry. This can lead to thrust asymmetry, which can then lead to coning. Four fins can help eliminate coning to a degree, but it's still something to design for and consider, especially if you're flying a longburn motor.

Yup, now you mention it, that was one of the things that I heard talk about this last weekend, but my brain is still full and processing :)

Nope, Booster motor will be normal core BATES, sustainer will be the moon-burner, but it seems that this type of motor is the preferred for sustainer.

(off topic; I found it funny that I had two separate people offer me $$ on the spot for the M840 at BALLS, I could have made quite a profit!!, most others just wide eyed asked "where did you manage to get that?" ... "Oh, it's been in my garage for the past 3 years.. ")
 
making a long story short... electronics problem.

I'm actually sorta glad you had electronics problems. There was a flight where the sustainer made a sharp turn (not a good thing). I thought that was your flight, so I'm releaved it wasn't. We can reload....

Jim
 
hmm... I mentioned earlier that I have a 54mm Loki M sat here. Just for S&G's Pete and I wondered what would be the result of stacking this beasty on top of the long burn M840.

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So... sustainer exceeds Mach 3, but, doesnt light until 20,000ft. So, this has got me thinking of sustainer friction heating.. my limited brain capacity tells me that a long burn to get it to height and then blasting speed at an altitude where the air is thinner, would give me more N's for the $.

Just a thought
 
So.... thoughts have been thunked.... and the plan is still 'fly what i got on the motors I have', unless I can source an Imax for that booster.
 
Spent the winter thinking long and hard on this project.

I believe that the sustainer is about as good as it could get, mechanically, but would do with a few tweaks electronically.

The booster needs a complete rebuild.
I need to gain more experience.

So... moving to a new thread... Vogon Poetry Mk 2
 
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