So, maybe I'll try a three-stager

plugger said:

Hi Jim,

You're correct, the firmware comes with the AltOS installer but it doesn't automagically update the device. You have to plug the EasyMega directly into your computer and run the process manually via the AltOS GUI. The instructions for how to accomplish this are on page 60 of the AltusMetrum manual.

Click to expand...

I did that back in September. I'm trying to recall the details, but I got the firmware separately from Keith (I think Keith referred to me as his Guinea Pig). I do not know exactly how others did their updates before Balls. Sorry for not being clear on that.

Jim

Edit - Turns out I was "the first test monkey".

JimJarvis50 said:

I did that back in September. I'm trying to recall the details, but I got the firmware separately from Keith (I think Keith referred to me as his Guinea Pig). I do not know exactly how others did their updates before Balls. Sorry for not being clear on that.

Jim

Edit - Turns out I was "the first test monkey".

Click to expand...

Thanks for the clarification Jim. And thanks again for documenting your experiences here.

drew

So, I'm planning to try the three-stager at Balls again this year. This will be the fourth try. In 2014, the 2nd stage didn't light due to tilt (which was a good thing). In 2015, I made 132,000 feet, and in 2017, the 2nd stage didn't light due to an altimeter bug (which was also a good thing). Rumor has it that the replacement N5800 for the first stage will be in my hands next weekend (yet another good thing).

Actually, I say "launch the three-stager again", but in reality, the third stage and the top of the first stage is the only original equipment. The current model has the spin can on the first stage and a vertical stabilization system that I have increasing confidence in. The second stage was new for last years flight.

Over the winter, I have upgraded lots of little things from last year. One area of focus has been the "keys" that hold the various sections in alignment. When controlling roll, turning of the sections relative to each other isn't a good thing, so all of the keys have been upgraded.

Since there was no launch today, and since it isn't horribly hot yet, I made this the "put the rocket on the rail" day. The idea is to test fit everything, make sure the fins clear the obstructions and make sure I have all of the little pad pieces accounted for. My rail is sort of an I-beam design. Normally, I have to assemble the whole thing at the launch. This year, I expect to have a longer trailer to take out my equipment, so the rail only needs to be broken into two parts and an extra rail section. So, today was about 80% of the rail assembly for the flight.

One other change I have made is to add an alignment guide for helping to load the booster on the rail. Alignment is real important given the PML rail guides that I use, and keeping the "index pointer" just above the guide board makes loading the rocket easy. I did this for a 6x4 two stage flight in 2016, and it worked very well.

Additional pics include two sets of "keys" (between the stabilization spool and the 2nd stage and between the 2nd and 3rd stages), and the whole rocket loaded.

Jim

Looks great Jim! I love the key idea as well, I’ve been doing that on my last couple builds too - nice and easy

Nice! But what's with the fins on the second to last pic? They look very fwd swept...

AdAstraPerAspera said:

Nice! But what's with the fins on the second to last pic? They look very fwd swept...

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I suspect that's just from being zoomed in a little. The picture is of the transition from the 4" 2nd stage to the 3" 3rd stage. Maybe the attached will help.

Jim

JimJarvis50 said:

I suspect that's just from being zoomed in a little. The picture is of the transition from the 4" 2nd stage to the 3" 3rd stage. Maybe the attached will help.

Jim

Click to expand...

Okay, got it. The last pic seemed to show no trailing edge angle at all, while the second to last showed a lot... Camera angles do funny things sometimes.

This pic shows what it going on nicely. Thanks!

So, it looks like Balls is about 6 weeks out. Usually around this time, I post my electronics configuration just in case someone can catch the errors I will inevitably make.

Just as a reminder, this is a three stage project with a spin can on the booster and an active roll/yaw/pitch stabilization module under the second stage. It's similar to the project last year, except the sustainer motor is a CTI M1430, which I hope will be easier to light then the Gorilla M745 that I've used in the past. It raises the 3rd stage speed quite a bit and the simulated altitude is somewhat higher at 187K. The attached flight profile for 2017 is attached, but the 2018 version is the same except for the third stage motor. There are lots of other changes, but the N5800 and N1560 in the first and second stage are the same.

The flight programming this year is based on the new EasyMega 1.8.6 firmware. The changes with this firmware allow the flight to be based on timing, instead of burnout detection, which makes things a bit easier. One change in the firmware, though, was to eliminate the ascending/descending flags, so I'm not quite certain how to program barometric apogee-related things in the third stage. That would be something to look at. As always, I can assure everone that I have made errors and that there is something to catch to help make my flight work. If you have a spare moment, please take a look.

Jim

View attachment 359547 View attachment 359548 View attachment 359549

Jim; How is it that you can have both "pressure increasing" and "pressure decreasing" checked on the 4th channel/first stage Raven?

Wallace said:

Jim; How is it that you can have both "pressure increasing" and "pressure decreasing" checked on the 4th channel/first stage Raven?

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When you select the "Output disabled" menu item, that's how the channel gets configured (automatically). Makes sense.

I mentioned previously that the new 3rd stage motor is the CTI M1430. This will be in an AMW case using "the hub". One change I made in the motor was to replace the plastic, non-stepped insulation disk with an Aerotech metal disk. To make that fit, I had to shorten the top grain by about 3/16" of an inch, which was a bit of a trick given that the grain was glued into the liner. The combination of the CTI reload, the nozzle carrier and the AMW case makes this motor very difficult to assemble.

Jim

Ok, so you're simply not using output #4? How did you manage to shorten the glued in grain? I imagine an end mill and lots of "Etch-A-Sketch" or do you do cnc?

I did this on an M685 where the last grain stuck flush with the top of the liner. I used a box knife and Xacto to cut the grain down. It wasn't that hard to do.

Wallace said:

Ok, so you're simply not using output #4? How did you manage to shorten the glued in grain? I imagine an end mill and lots of "Etch-A-Sketch" or do you do cnc?

Click to expand...

JimJarvis50 said:

When you select the "Output disabled" menu item, that's how the channel gets configured (automatically). Makes sense.

I mentioned previously that the new 3rd stage motor is the CTI M1430. This will be in an AMW case using "the hub". One change I made in the motor was to replace the plastic, non-stepped insulation disk with an Aerotech metal disk. To make that fit, I had to shorten the top grain by about 3/16" of an inch, which was a bit of a trick given that the grain was glued into the liner. The combination of the CTI reload, the nozzle carrier and the AMW case makes this motor very difficult to assemble.

Jim

Click to expand...

Jim, out of curiosity, what motor is the CTI M1430 - OD/Grains/Propellant ? I can't find it.

Wallace said:

Ok, so you're simply not using output #4? How did you manage to shorten the glued in grain? I imagine an end mill and lots of "Etch-A-Sketch" or do you do cnc?

Click to expand...

Actually, I stuck some sandpaper on the Aerotech forward seal disk with some double sided tape and had at it until the seal disk got seated. I'm pretty low tech.

Jim

Charles_McG said:

Jim, out of curiosity, what motor is the CTI M1430 - OD/Grains/Propellant ? I can't find it.

Click to expand...

Crap. It's the 5-grain M1401 white. An alternate was the 4-grain M1230 imax. I've been mixing these up, so to speak, quite regularly.

Jim

JimJarvis50 said:

Crap. It's the 5-grain M1401 white. An alternate was the 4-grain M1230 imax. I've been mixing these up, so to speak, quite regularly.

Jim

Click to expand...

Either way, it adds up to about a 5% P.

JimJarvis50 said:

Actually, I stuck some sandpaper on the Aerotech forward seal disk with some double sided tape and had at it until the seal disk got seated. I'm pretty low tech.

Jim

Click to expand...

Field expedience, gotta love it.

Charles_McG said:

Either way, it adds up to about a 5% P.

Click to expand...

Yes, I had to submit my paperwork twice, but I'm firmly in the queue at this point.

Jim

JimJarvis50 said:

I had a problem with the O motor. Basically, the HTPB adhesive provided with the kit didn't set up. Not sure why. The grains were wetted with the old adhesive, so the first step of the cleanup was to "peel the grains" to remove the saturated paper. That left the grains pretty loose in the liner, so the question became how to best build back up the diameter of the grains. I got lots of advice, but I ended up working with the technical folks at CTI and we devised a plan using HTLO, Papi 901 and microballoons. The microballoons thicken the HTLO and provide some thermal insulation.

Click to expand...

JimJarvis50 said:

To assemble the motor, the space between the rings was coated with HTLO/Papi and then frosted with the HTLO/Papi/MB mixture. I used 10% microballoons by weight. I'm pretty sure that most of the volume between the rings got filled with the mixture, and I'm happy with how it turned out. So, the plan is to fly the motor in a few weeks.

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I know I'm replying to an old post here, but I was curious how this ended. Obviously the motor flew - were all the indications positive of a successful salvage operation?

CoyoteNumber2 said:

I know I'm replying to an old post here, but I was curious how this ended. Obviously the motor flew - were all the indications positive of a successful salvage operation?

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The flight file appears to be on a different computer, but so far as I know, the motor worked just fine (maybe a bit too fine). I had a very hard time getting the liner out of the motor case, and it wasn't long after that that I discovered that the motor tube had been slightly banana'd when the sustainer landed. Crap. The liner itself looked normal. So, I would say the recovery of the motor, with the help of CTI, went just fine.

Jim

JimJarvis50 said:

So, it looks like Balls is about 6 weeks out. Usually around this time, I post my electronics configuration just in case someone can catch the errors I will inevitably make.

Just as a reminder, this is a three stage project with a spin can on the booster and an active roll/yaw/pitch stabilization module under the second stage. It's similar to the project last year, except the sustainer motor is a CTI M1430, which I hope will be easier to light then the Gorilla M745 that I've used in the past. It raises the 3rd stage speed quite a bit and the simulated altitude is somewhat higher at 187K. The attached flight profile for 2017 is attached, but the 2018 version is the same except for the third stage motor. There are lots of other changes, but the N5800 and N1560 in the first and second stage are the same.

...

Click to expand...

Thanks for that. You're getting ever closer to the magic 300,000 feet altitude number.

Best of luck on this flight - and on the even higher flights to follow!

Bob Clark

Well, I was able to do my three-stage flight at Balls on Friday. Just as a reminder, this is the N5800 to N1560 to M1401 with the spin can and active stabilization. The up part was great. Everything was clearly visible and quite straight (I think), and the spin can and stabilization system seemed to work as intended (pending an analysis of the data). The down part was mostly good, except that the second stage came in hot. Not many clues as to why. As usual, my flights have a few issues, and this flight did too, but I'll take the overall result. The altitude was around 160K, but I think I left a few feet on the table. There is lots of data to analyze, but I won't get around to it until next weekend.

A few pics are attached, including two pics posted by Jim Wilkerson on the Tripoli Facebook page.

Jim

Congratulations! 160K is phenomenal.

Nice one Jim.

I take it you managed to recover the entire 2nd stage? Guess the electronics did not enjoy the rapid stop at the bottom.

Jim , congrats. While not a perfect flight with the recovery issue of stage two, I consider this a success. It flew straight, all three stages lit, it went really high, and you retrieved everything. I look forward to more detail once you get through the data.

Outstanding Sir!

SpaceManMat said:

Nice one Jim.

I take it you managed to recover the entire 2nd stage? Guess the electronics did not enjoy the rapid stop at the bottom.

Click to expand...

Well, we pulled out what we could. Seems like it was mainly the lower air frame with the motor (about a third of the motor was peeled back). However, I'm not certain that the upper air frame was there. Further, the 4x3 transition that was the "nose cone" for this stage came off and was recovered not far away from the lower section. I think the main just popped and the transition section came loose. However, I'm going to take a quick look around that area just on the chance that the upper air frame came free. Stranger things have happened.

Jim

Yes, I do too. The boost part was really nice. So far, I don't have a complete video of the flight, but I'm sure one will appear.

It was also nice that Steve Shannon was able to see the flight, after working so hard to try to fly the rocket twice last year. And it was great that Kip helped out this year.

Jim

Outstanding! Looks like they all lit on the money.
I would be interested in what altitudes the upper stage motors lit, when you publish your data.
Did you use the pellets?

Salutations on an extraordinary and inspiring achievement