Tuesday, November 16, 2010

Some thoughts on an orbital launcher.
  • All stages contribute the same DV (Bad assumption)
  • 9500 M/Sec Delta V may not be enough for a really small vehicle.
  • MR is achieved MR per stage including payload.
  • We assume the MR is the same for each stage (again a bad assumption)
This table shows you the minimum ISP performance you need given an achieved MR and a number of stages. For Reference the Blue Ball with no payload and no legs had a MR of between 5 and 6. If my notes are correct the Falcon 1 first stage with no Payload and no 2nd stage has a MR of about 16.

MR is down the left side, number of stages is across the top.

Minimum ISP
Stages 4 3 2 1

2 349.3 465.7 698.6 1397.1
3 220.4 293.8 440.7 881.5
4 174.6 232.9 349.3 698.6
5 150.4 200.6 300.9 601.7
6 135.1 180.2 270.2 540.5
7 124.4 165.9 248.8 497.7
8 116.4 155.2 232.9 465.7
9 110.2 146.9 220.4 440.7
10 105.1 140.2 210.3 420.6
11 101.0 134.6 201.9 403.9
12 97.4 129.9 194.9 389.7
13 94.4 125.9 188.8 377.6
14 91.7 122.3 183.5 366.9
15 89.4 119.2 178.8 357.6
16 87.3 116.4 174.6 349.3
17 85.5 113.9 170.9 341.8
18 83.8 111.7 167.5 335.0
19 82.2 109.6 164.4 328.9
20 80.8 107.8 161.6 323.3
40 65.6 87.5 131.3 262.5

The second chart shows the vehicle gross lift off weight given a 1Kg payload and assuming that the empty stages weigh the same as the payload they are lifting.

GLOW multiplier

4 3 2 1

2 256 64 16 4
3 1,296 216 36 6
4 4,096 512 64 8
5 10,000 1,000 100 10
6 20,736 1,728 144 12
7 38,416 2,744 196 14
8 65,536 4,096 256 16
9 104,976 5,832 324 18
10 160,000 8,000 400 20
11 234,256 10,648 484 22
12 331,776 13,824 576 24
13 456,976 17,576 676 26
14 614,656 21,952 784 28
15 810,000 27,000 900 30
16 1,048,576 32,768 1,024 32
17 1,336,336 39,304 1,156 34
18 1,679,616 46,656 1,296 36
19 2,085,136 54,872 1,444 38
20 2,560,000 64,000 1,600 40
40 40,960,000 512,000 6,400 80

The two bold numbers are about where I think my notional vehicle will land on this chart. This was a 1Kg nanosat with 1Kg of support structure would have a gross liftoff mass of ~2200 lbs, and the engine performance is a relatively easy ISP of 232 (Easy in vacuume, a bit harder on the first stage) Total Vehicle empty wt would be between 500 and 600 lbs.

you can do some really gross things... like a monoprop 4 stage launcher... MR 6 Glow for 1Kg payload is 40000 lbs.

Monday, November 15, 2010

My weekend ......Frustrating

We went out to FAR and set up the test stand.
Everything checked out we put in the fuel (gasoline) and
were preparing to load peroxide. When we opened the cap
there was a black substance stuck to the cap, when we open more fittings
there was an unknown black substance. The tank had been a peroxide tank.
It sat in the garage sealed for 2 years. On Friday we hydroed the tank and say no sign of contamination. The rough drive out to FAR dislodged some kind of black/brown powder from the inside of the tank. The powered looks like Iron rust on close inspection and is very reactive with peroxide. So the test was scrapped. It makes me wonder if something is leaching out of the aluminum after being stored for a long period.

We need to add interior visual inspection to the check list for all stored tanks, even if properly sealed and stored.

We worked on the big generator, burning the stale diesel and replacing with fresh. (Still not running)

On the plus side we did get our primary storage container cleaned up.
(As a result the garage at home is in distress once again)

We tested some of the super chemical compatible K190 resin for peroxide compatibility. It responded almost identically to the easier to get Vipel F010. A slight etching of the surface.

We'll see if we can fabricate a new test stand tank this week, and try again next weekend.

Friday, November 12, 2010

My Weekend....

I just finished hydroing the test stand and setting the pressure relief valve.
I have to hook up two pressure transducers to the electronics and the Stainless motor is ready to test. We will probably go out to FAR sometime Saturday and test the motor, work on our generator, and clean out our container. The clean out the container part probably means we will be out there overnight Saturday night and return some time Sunday.

Wednesday, November 10, 2010

Ways to save the world... and more Rockets

Saving the World
Any long time blog reader reader has already heard my rant about the only way to really spread an American standard of living to the entire population of the world requires that we find new resources, not just recycle our soda cans. I believe that off planet resources will be a significant part of the solution for things like rare earth metals, platinum group metals, expanding humans into the solar system etc.... The other half of this is a cost effective green energy source. I'm still very skeptical about the ability of space based solar power to solve the energy issues here on earth. I think its much more likely that small modular fisssion reactors and hopefully fusion will solve the energy problems.

A few weeks ago I posted about LPP. since that time I have visited their facility. I went through the lab and got to watch several "fusion" shots. They have multiple different ways to detect neutrons and are clearly generating neutrons via D-D fusion. They have obviously spent a fair bit in building their lab, but none of it was wasted in any way. They have good instrumentation and a well setup shielded room, but the rest of the lab space itself could be generously described as spartan. Its obvious that the people working on the project are passionate about what they are doing and believe they have a pretty good shot at making it all work. As a result I've decided to personally invest some $ in their business. If you are an accredited investor give them a call.

Back to Rockets....
I've started in earnest to work on a plan for winning the Nano Sat contest. There was a big meeting to kickoff the contest last week and in my mind the only significant questions left about the contest will be
  • How do they resolve the no government funding rule,
  • Who will be the allied organization.
The overall goal of centennial challenges is to encourage innovation from individuals and companies that are not part of the traditional aerospace environment. The goal of the specific Nanosat prize is to try and kick start a low cost nanosat launcher. At some level the two goals are in conflict. There are many small SBIR sized companies that have received government funding to work in this area, and so excluding government contractors from the contest will limit the pool of people that might succeed, at the same time including people receiving significant government funding really violates the spirit of the centennial challenges.
Personally I would like to see the same no government $ rules that were part of every previous centennial challenge.

On the technical and regulatory side of the house many many questions remain.

This weekend I hope to finally fire my stainless printed motor.
Building more real hardware really requires that I get more details of my notional launcher nailed down.

Friday, November 05, 2010

A personal non rocket tale and warning.

This has NOTHING to do with rockets but I think its important.
For the last two plus years I've felt tired and somewhat depressed.
I just thought I was getting older and though it was normal to feel drained all the time.
Last year while I was driving toward the LLC I was not getting a lot of sleep, largely by choice.

After the LLC I was looking forward to getting my energy back but no matter how much sleep I got, I woke up feeling trashed. I could barely work past 9pm without becoming dangerous and/or unproductive.

A month or so ago My wife went up to Long Beach for 4 days.
On Sunday I slept by myself and Monday I felt terrible. On Monday I drove up to Long Beach and spent the night with her, Tuesday I felt fine. Tuesday night I was home alone and Wednesday I felt terrible. Wednesday night she came home and Thursday I was ok.
I pointed this out to her and she said "when you roll over on your back you snore and I elbow you to make you roll over."

A light goes on My 80 yr old father has Sleep Apnea so I call my Dr and explain the A-B-A-B experiment I had just done. He says he will schedule me for a home sleep study..... 10 days later its tied up in the insurance authorization never never land so I buy myself a recording pulse oximeter and record a nights sleep. I find that my O2 sat goes to less than 80% more than 20 times in a 6 hour recording.

Armed with my data I say dam the insurance and full speed ahead. So I go in and see a sleep doctor that schedules a formal sleep study. The result is that I was having 33+ apneas an hour,
and not just while I was on my back.

When this happens your body senses that something is wrong and sets off all the panic alarms and wakes you up. As a result anytime I got into REM sleep it was short lived and unproductive.
You also get to activate your fight or flight alarm hormones every night. It also explains why I would wake up a 3 am feeling exhausted yet unable to go back to sleep. My body was in panic alarm mode. I was inadvertently running the REM sleep deprivation experiment.

I got a CPAP machine on Wednesday this week. Its only been two days, but I feel 1000% better. I wake up feeling rested, I worked late in the shop last night and got a lot done.

I'm writing this so anyone that snores and is feeling tired will seriously consider getting a sleep study. I did not look forward to sleeping with the Mask and hose etc.. but the change in how

I feel has been so dramatic that I would do it in an instant even if it meant wearing the mask 24/7. So if any of you are feeling tired and run down, not yourself depressed think about a sleep study.

I realize that something once written is on the Internet forever and that this revelation
might cause me some grief in the future while looking for jobs, contracts etc.... but if just one person reads this and it prods them to get checked out it will be well worth it.

As a side note I hope this will mean a lot more progress on the rocket projects!