So, maybe I'll try a three-stager

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Looks like you might need a boat to get out of Texas. Hope to see you at Airfest, I'm finally bringing a two stage rocket to the rocket pasture!


Still don't know about our launch Saturday. It has stopped raining anyway. I'd love to fly my two-stager at air fest, but with the three-stager prepped, I don't have enough equipment left to field a team.

Jim
 
Still don't know about our launch Saturday. It has stopped raining anyway. I'd love to fly my two-stager at air fest, but with the three-stager prepped, I don't have enough equipment left to field a team.

Jim

Not headed for BALLS this year, but I am headed to AirFest, need help?
 
Steve is sitting across the table from me and says he owes you a beer if the Trailer with a capital T can help track his and Kip's project.

-Clay

Two things:

1. More than a single beer, seriously have you seen my trailer.

2. Damn right, I can track anything.

P.S. email me frequencies and mode ASAP.
 
After quite a bit of thought, I have completed the first draft of my launch checklist. This covers preparations for travel, for the day before the launch and for the launch day itself. This will be of no interest to anyone except to illustrate how I'm trying to manage the complexity of this flight. It's just not possible to keep the order of everything in my head. One strategy I'm trying to use this year is to have as much done prior to the launch day as possible. Last year, we were pretty tight against the end of the launch window, and the checklist helped us to get the rocket launched in time.

Jim

View attachment Detailed Checklist.pdf
 
Well, we leave for Balls in less than a week. The only question now is, what happened to July, August and September? In spite of the fact that this launch has snuck up on me, I'm pretty much ready to go. Now, it's just a matter of executing the plan. This assumes that the FAA comes through with the COA (no news is good news?).

This will be the third three-stage attempt. On the first try, the second stage motor was aborted due to tilt. The second try reached 130K feet, but it wasn't a very good flight. A couple of videos from that flight, explitives not deleted, are here:

https://youtu.be/9pfy_Nyc9z8
https://youtu.be/eHloNCGlYz4

I'm hoping for a better flight this year. Just for the record, it's N5800 to N1560 to M745, projected for somewhere between 0 and 170K feet. The rocket has a spincan on the first stage and active roll and vertical stabilization between the 1st and 2nd stages. What could go wrong?

I did have an issue with the EasyMega in the 3rd stage, leading to a certain amount of panic last weekend. Apparently, the calibration of the accelerometer can drift, and the result of that is that the altimeter goes into idle mode instead of pad mode even when the rocket is vertical. Fortunately, Keith ran into this issue at Airfest and had a patch pretty much ready to go. I really appreciate the support! Everything looks fine at this point.

Now, I just need a few hundred things to go right and we'll get this project into the air!

Jim

IMG_1317.jpg

IMG_1319.jpg

IMG_1322.jpg
 
looking beautiful! really looking forward to seeing this up close!
No, I havent as yet heard a thing back and i am thinking "no news is good news"

I had the same problem with the TeleMega. I couldnt get it to go into pad mode, ended up having to go through "putty" and manually recalibrate and reset, sounds similar!
 
"projected for somewhere between 0 and 170K feet"

Lol - hope it goes well, sad I'm gonna miss it this year again.
 
Jim,
I offered to help. If you still need me, I get to Gerlach on Thursday sometime. We have a board meeting on Thursday night. After that just let me know where and when you need me to do something. I'll warn you right now you're getting unskilled labor, but I am trainable.


Steve Shannon
 
I did have an issue with the EasyMega in the 3rd stage, leading to a certain amount of panic last weekend. Apparently, the calibration of the accelerometer can drift, and the result of that is that the altimeter goes into idle mode instead of pad mode even when the rocket is vertical. Fortunately, Keith ran into this issue at Airfest and had a patch pretty much ready to go.

Jim

Jim can you share the patch? You have me paranoid.
 
Jim,
I offered to help. If you still need me, I get to Gerlach on Thursday sometime. We have a board meeting on Thursday night. After that just let me know where and when you need me to do something. I'll warn you right now you're getting unskilled labor, but I am trainable.


Steve Shannon

Yes, Steve, I'm counting on you, and thanks. According to the rules, which we're supposed to self-enforce, I'm only allowed to have three persons at the away cell (other than me and my wife). I'm hoping you'll be one of them. It shouldn't take much time this year - just a few hours. The pad will be set up in advance, and the rockets will be (almost) ready to place on the rail after an electronics check. Where I need help is getting the rocket loaded on the rail, monitoring the checklist to verify all steps are completed, and then tracking the four pieces of the rocket during the launch. And someone should take a little video too.

At this point, I don't know what day I will be launching on. That will depend on the weather, and in particular, the upper wind forecast. That forecast will begin to be available early next week.

Jim

PS - If you happen to be in Austin on Saturday, I could use help packing up. It's supposed to be hot and humid. Sigh....
 
Jim can you share the patch? You have me paranoid.

Just contact Keith for a link. You'll need a new operator interface version (with a "calibrate accelerometer" function) and then you'll need to flash the altimeter with the correct firmware. I would recommend doing it if any of your control logic involves calculated velocity. This is a beta program, and I have been designated as Guinea Pig #1. You might be #2, so you will need to make a choice.

Jim
 
Just contact Keith for a link. You'll need a new operator interface version (with a "calibrate accelerometer" function) and then you'll need to flash the altimeter with the correct firmware. I would recommend doing it if any of your control logic involves calculated velocity. This is a beta program, and I have been designated as Guinea Pig #1. You might be #2, so you will need to make a choice.

Jim

Yikes. Yeah I've been a guinea pig for Altus for a couple years now. What's new...

You're just using velocity (< 250 m/s) for backup apogee?
 
Yikes. Yeah I've been a guinea pig for Altus for a couple years now. What's new...

You're just using velocity (< 250 m/s) for backup apogee?

I have several channels that have a velocity criteria. I set the velocity value on the high side and I try not to use it if possible, but the latest firmware has some enhancements that should make using velocity for mach lockout more reliable. I don't know much about the specific issue of the accelerometer drift, but I suppose it's possible that it might affect burnout detection as well. Just speculating.

Jim
 
I have several channels that have a velocity criteria. I set the velocity value on the high side and I try not to use it if possible, but the latest firmware has some enhancements that should make using velocity for mach lockout more reliable. I don't know much about the specific issue of the accelerometer drift, but I suppose it's possible that it might affect burnout detection as well. Just speculating.

Jim

K, Keith just sent me the patch. I'm going to load it on both sustainer flight computers. He recommends it for reducing integration error. Not sure if that will improve tilt sensing too.
 
And yeah if it improves the accelerometer I would love to use velocity to light the sustainer instead of a timer. Flying EX in the booster and sustainer make it much more difficult to predict my coast and pick a time to punch the sustainer.
 
K, Keith just sent me the patch. I'm going to load it on both sustainer flight computers. He recommends it for reducing integration error. Not sure if that will improve tilt sensing too.

Well, just speculating some more, I would have expected the gyro accelerometers to do the sensing of the board position. It's tilt after all. But I guess the axial accelerometer is used for this such that if it drifts a relatively small amount relative to its range, it might think it is not vertical. The accelerometers associated with the gyros are not used during the flight, and I don't think this issue is related to tilt detection.

Jim
 
K, Keith just sent me the patch. I'm going to load it on both sustainer flight computers. He recommends it for reducing integration error. Not sure if that will improve tilt sensing too.

K reminded me to check all the Altus Metrum stuff that i have (TeleMetrum and TeleMega) and make sure that the firmware is updated to 1.7 on all of them. There can be a problem where the GPS loses lock and switches off and soft reboots the unit. Luckily it comes back on with arms apogee and main, but not what you want in a real high flight.

the .ihx flash files can be found on the Altus Metrum site, and it is simple using the "Flash Image" option in Altos
 
Ya I don't trust any hobby integrated GPS flight computers. Too many bugs across all manufacturers -particularly RF issues. And they all run lower power transmitters than standalone units like the Beeline.

I will double check all firmware once I start prep this weekend.
 
Hi Jim,

Can you post a link to the wind forecast site you're using?

Thanks,
Jerry O


 
Yes, Steve, I'm counting on you, and thanks. According to the rules, which we're supposed to self-enforce, I'm only allowed to have three persons at the away cell (other than me and my wife). I'm hoping you'll be one of them. It shouldn't take much time this year - just a few hours. The pad will be set up in advance, and the rockets will be (almost) ready to place on the rail after an electronics check. Where I need help is getting the rocket loaded on the rail, monitoring the checklist to verify all steps are completed, and then tracking the four pieces of the rocket during the launch. And someone should take a little video too.

At this point, I don't know what day I will be launching on. That will depend on the weather, and in particular, the upper wind forecast. That forecast will begin to be available early next week.

Jim

PS - If you happen to be in Austin on Saturday, I could use help packing up. It's supposed to be hot and humid. Sigh....

Austin sounds lovely but unfortunately I'll be in Billings, Montana.
I'll send my cellphone number so you can call me and we can meet up at Gerlach.
 
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