L3 Success: Compulsion, 4-in Fiberglass Frenzy XL build

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I did some charge testing over the weekend. I used the Eggtimer Quantum's wireless test feature to remotely fire the charges.
My calculations were pretty much right on:
⦁ Drogue 4F Black Powder Charge: 1.7 grams
⦁ Main 4F Black Powder Charge: 1.9 grams

I had the rocket at a shallow upward angle to test the drogue charge. It was a nice powerful "pop" and it shot the payload section out, hit the ground about 10 feet ahead and skidded to a stop extending 18' of the 25' Kevlar shock cord. If I had the rocket angled up more, it would have gone to full extension. I'll plan to use 1.7g for the primary drogue charge, and +25% more = ~2.2g 4F for the backup drogue charge.

The main charge test had the rocket at a slightly higher upward angle. It was also a nice separation and "pop". The heavy nosecone with integrated tracker shot out, hit the ground and skidded to a stop, extending 22 ft of the 25 ft shock cord. I'll plan to use 1.9g for the primary main charge, and 2.5g for the backup main charge.

I took some deployment charge test videos. but I'll have to post those later next week.. since I'm scrambling to get everything ready for my L3 flight this Saturday at TCC's Dairy Aire Launch Event.

I've got the nosecone, payload tube and altimeter switch band painted Gloss Red Apple using Rustoleum Painter's Touch 2X. Tonight, I finished sanding the booster and those tedious fin fillets and have the first coat of primer on.. I'll be painting the booster Gloss White. I also have the standard Madcow Frenzy XL vinyl decals to apply.. time permitting.
 
FYI, I tested my F200 the same way, and settled on my charges based on similar results to yours. Upon watching the video of a flight, I saw that both the NC and booster harnesses were extending and snapping back. Next flight I am going to reduce my charges. Turns out that the ground resistance required more powder to separate than in the air.

Go big for sure on first flight, but if you can get good video, check your harness extensions.
 
If you think about it the NC or NC/Payload bay are unsupported while the booster section is sitting on the stand. In flight there should be less friction because both sections should have the same amount of support from the air flowing over them.
 
FYI, I tested my F200 the same way, and settled on my charges based on similar results to yours. Upon watching the video of a flight, I saw that both the NC and booster harnesses were extending and snapping back. Next flight I am going to reduce my charges. Turns out that the ground resistance required more powder to separate than in the air.

Go big for sure on first flight, but if you can get good video, check your harness extensions.


I'll be flying an smaller M motor Saturday.. to roughly 13,000' AGL. Thus, it's unlikely I'll get to see the drogue separation and cord extension. With luck, it will be close enough and I'll have eyes on it when the main charge fires. I always like to see/hear the primary charge separate the rocket, and then seconds later hear the backup charge an see the second puff of smoke.

Having thought about this again, I realize that I forgot to mention that when I tested the drogue charge, I used an AeroTech RMS 54/1706 case with the AeroPack 54-75mm adapter to fill/plug the motor tube. With this smaller case in the rocket, there's more air volume to compress. Using the same 1.7g 4F drogue charge with the larger 75mm motor should result in greater pressure and thus a more energetic separation. I had calculated the charge assuming the 75mm motor would be installed. If I have time, I'll run some numbers to see how much more BP I should use with the smaller motor case. However, given the good test results and your comments, I'll carefully consider reducing the charge after I get a better feel for how energetic they are during lower altitude flights where I can see the apogee events.
 
If you think about it the NC or NC/Payload bay are unsupported while the booster section is sitting on the stand. In flight there should be less friction because both sections should have the same amount of support from the air flowing over them.

That's a good point. I also have it in my mind that the cords will easily make full extension in flight as there will be no ground friction to stop motion.
 
I was planning to do the L3 flight using an AeroTech RMS 75/6400 M1315W motor at XPRS, Blackrock NV. I picked up the motor, reload adapter system and a M1315W reload some months ago. However, since I wasn't ready in time for this launch, my flight will be at Tripoli Central California's (TCC) October Skies launch event this Saturday. They have a standing waiver to 16,811 ft AGL. Unfortunately, with the M1315W I would be getting too close to the waiver altitude for comfort. Thus, I'm now planning to fly on a M1297W to roughly 13,000 ft per my simulation. During discussions on this subject, I was made aware that there is data from other TCC fliers that has a 29.5 lb build of this rocket getting about 1,000 ft higher than my simulations of he same motor. Thus extra caution is warranted. I'll be working to get everything ready so that I can get an early start Saturday.
 
Good thought process and pre-check.
The M1297 can take these long 4" Madcow kits up there for sure. A 35 lb modified DX3 XL went 10,700 on it.
 
I got 14k on a M1780 in my 22lb Punisher 4. I got 14.9k with the M1315 in the same bird.
 
Good thought process and pre-check.
The M1297 can take these long 4" Madcow kits up there for sure. A 35 lb modified DX3 XL went 10,700 on it.

I got 14k on a M1780 in my 22lb Punisher 4. I got 14.9k with the M1315 in the same bird.

Thanks for the data points.
I will have a final weight tonight.. but I think I'm goin to be around 28.5 lbs with a M1315W or 26.75 lbs with the M1297W. I've been getting things ready and it's 2am! It's raining pretty good tonight, hope the rain puts out the fires in CA.
Lots more to do tomorrow night.
 
Last week I added a third non-deployment altimeter to the avionics bay, a Jolly Logic Altimeter 3. I used the Jolly Logic assessory mount and two 6-32 wood screws into the 1/4" plywood to secure it. The Y-axis is aligned with the rocket's vertical axis. It can measure up to 25 Gs acceleration on each of the 3 axes. This was sufficient to capture acceleration data for my L3 certification flight without saturating. If there's a strong shock upon the shock cords pulling tight, it may saturate then. This little altimeter will also record pressure information, which will be helpful when analyzing data for the impact of shocks building/receeding during transition to/from supersonic flight. I installed it such that the on/off button is lined up directly below the altimeter bay vent hole. I'll simply need to slide in a screwdriver and press the button once to turn it on, then connect with it via Bluetooth on my Android Cell Phone to turn on the recording and download data. Here's a picture of this simple installation:

JL Altimeter3 Installation IMG_3885 sm.jpg
 
I decided to paint this rocket the stock Madcow Frenzy Colors, Red and White. I have had good luck with Rustoleum Painter's Touch 2X on two cardboard rockets, so I thought I'd try it on this Fiberglass kit. My process was pretty standard:
Sand
Wash and dry
Alcohol wipe down
Tape ends and plug holes
Prime
Wet Sand
Rinse/wipe off all surfaces to be painted
Paint Light Coat
wait a few minutes
Paint a Second Light Coat
Pick off Bugs
Curse a few times
Allow to dry.

Sanding
IMG_3774 1600x1200.jpg IMG_3758 1600x1200.jpg

Taping off end/edges of tubes:
IMG_3777 1600x1200.jpg

Paint:
IMG_3768 1600x1200.jpg

Av Bay Switch Band, Payload Tube and Nosecone are Gloss Apple Red
IMG_3767 1600x1200.jpg

Booster is Gloss White
IMG_3809 900x1200.jpg

All together, she looks pretty good:
IMG_3810 1600x1200.jpg IMG_3814 1600x1200.jpg
 
Saturday, October 21st, 2017, my family and I drove out to Helm California, to attend Tripoli Central California's (TCC) October Skies Launch Event.
I had made arrangements with my NAR L3CC, Dave R., to do my L3 certification flight with the Frenzy XL. Dave and James M. made up the certification team

I had originally been planning to fly it on an AeroTech RMS 75/6400 M1315W at XPRS @ BlackRock last month, but I was not able to finish building in time. TCC has a standing waiver for the Helm, CA launch site(s) at 16,811 ft AGL. After some discussion with James D, president of TCC, he asked that I lower my impulse to ensure that I didn't break the waiver altitude. Thus, I picked up an AeroTech RMS 75/5120 M1297W Saturday morning. Dave R. was generous and allowed me to use his RouseTech RMS 75/5120 motor, sans a forward seal disk. This was easier to use than having to fuss with my 6400 case and the reload adapter system, particularly since I use the forward closure eyebolt as a backup shock cord mounting point.

Initially, the winds aloft forecast was looking too brisk with winds above 9,000 ft in the 40 to 70 knot region. Fortunately, the forecast improved and winds were forecast to be less than 30 knots below 18,000 ft. The winds aloft after 2pm Saturday were forecast to be between 20 and 30 knots above 9,000 ft. Here's the numbers I had to go with:
FT 3000 6000 9000 12000 18000
FAT 3307 3415+11 3315+09 3218+03 3027-09


With that, I decided to go for it, and began loading the motor and connecting the altimeter charges. The surface winds, however, seemed to get stronger. Perhaps up to 15 kts. The flight was straight up, even with the stiff wind. Apogee was at 13,116 ft AGL, where the primary altimeter separated the booster from the payload smoothly and the Sky Angel Cert-3 Drogue kept things orderly during a nice descent at 79 ft/sec. This was a good rate given the altitude from which it was falling. The primary altimeter next separated the nosecone from the payload, deploying the 84" main parachute at 1,300 ft AGL. The main descent rate was slower than I predicted. For a long while, the rocket was only dropping at 4 to 10 ft/second. I'm guessing that a thermal was releasing off the dark plowed soil. However, in the final seconds before touchdown, the descent rate sped up to 16 ft/sec, which is closer to the 17.4 ft/second that I'd predicted for his size chute, rocket weight, local current barometric pressure and air temperature.
Below are some shots of the flight as well as a data plot from both the Altimeter3 and StratoLoggerCF.

IMG_3821.jpg
Dave R. giving the thumbs up.

IMG_3822 1600x1200.jpg
I'm worried about a speck of dirt on my fin.. lol.

20171021 L3 Cert Flight Launch1.jpg
The M1297W pressurizes and thumps off the pad.

20171021 L3 Cert Flight Launch9.jpg
Dirt clawds were blown about as the Frenzy XL accelerates straight up.
She flew straight up, with no weather cocking or coning.

IMG_3825.jpg
Recovery Photo, Dave has just wrapped up the main chute that had been inflated and dragging the rocket though the hard dry clay clawds. My new smooth glossy paint was severely damaged by dragging, it looks as if someone took 60 grit sandpaper and removed the gloss. I'll be debating how I might fix or refinish the whole rocket this week.


The Eggfinder TRS telemetry was received until the rocket was on the ground, about 1.3 miles downwind. The tracker gave excellent data from Apogee all the way down to the ground. However, after landing, stiff winds inflated the 84" Top Flight PAR84 parachute, and dragged the fully deployed rocket assembly another 0.25 mile downwind. My new paint job was destroyed, but the rocket was in perfect mechanical shape and ready to fly again.

20171021 FrenxyXL M1297W L3 CertFlightTrack View2 markup.jpg
Maphsphere GPS tracker coordinates for the filght.

20171021 FrenzyXL M1297 TCC October Skies Helm CA L3 Cert Flight.png
Jolly Logic Altimeter 3 Data Plot.

20171021 L3 Cert Flight Frenxy XL M1297W TCC October Skies Helm CA.jpg
PerfectFlite StratologgerCF Data Plot
 
Congrats! Sounds like a great flight. Can't wait to go for mine... I'll be flying my frenzy this weekend but just on a large 75mm k.
 
Congratulations Kevin. You did a great job. I'm sorry I wasn't available to take pictures of your launch.
 
Fantastic and very well documented. Congrats! Now go buy something really BIG! :cyclops:
 
Great job on your L-3 I liked watching your build progress. I had a Dynacom Anaconda that I flew in KS one year with the best paint job I had ever done. I was a very high gloss black. By the time I got to it had turned grey in color from being dragged across the KS land scape.
 
Congrats! Sounds like a great flight. Can't wait to go for mine... I'll be flying my frenzy this weekend but just on a large 75mm k.
THanks. I'll be looking forward to your onboard videos! I hope to integrate a camera on mine before the next launch. I'll likely fire a K2050ST or a K1103X next. I'm hopeing to hear a whistle after the hard-hitting K2050ST burns out.

Congratulations Kevin. You did a great job. I'm sorry I wasn't available to take pictures of your launch.
Thanks Chris. You had more important business hanging!

Fantastic and very well documented. Congrats! Now go buy something really BIG! :cyclops:
Thanks! Wait, an M isn't big enough?! =]

Congrats on your L3! Great flight and nice looking rocket.
Thank you. I wish it were still nice looking. I'll need to work on buffing out the surface and/or sanding and repainting. Ugh.

Gotta be happy with that. Welcome to L3 :)
I'm definitely happy. Seems like a load is off my shoulders. Thank you.

Great job on your L-3 I liked watching your build progress. I had a Dynacom Anaconda that I flew in KS one year with the best paint job I had ever done. I was a very high gloss black. By the time I got to it had turned grey in color from being dragged across the KS land scape.
Thank you. Did you repair the finish or live with it? I have a yellow and red crossfire.. so ever time I see your avatar, I think of it.

Congratulations on the successful L3! Now you need to repaint it.

Thanks Nathan. I'm not looking forward to reworking the finish. But I have an idea!... I'll just need to know your address so I can drop off the Frenzy for professional paint rework!
 
THanks. I'll be looking forward to your onboard videos! I hope to integrate a camera on mine before the next launch. I'll likely fire a K2050ST or a K1103X next. I'm hopeing to hear a whistle after the hard-hitting K2050ST burns out.


Thanks Chris. You had more important business hanging!


Thanks! Wait, an M isn't big enough?! =]


Thank you. I wish it were still nice looking. I'll need to work on buffing out the surface and/or sanding and repainting. Ugh.


I'm definitely happy. Seems like a load is off my shoulders. Thank you.


Thank you. Did you repair the finish or live with it? I have a yellow and red crossfire.. so ever time I see your avatar, I think of it.



Thanks Nathan. I'm not looking forward to reworking the finish. But I have an idea!... I'll just need to know your address so I can drop off the Frenzy for professional paint rework!

I was able to buff most of the scratches out. So I didn't repaint it. Our rockets will always get some dings if we fly them.
 
I didn't have an onboard video camera, but I managed to stitch together a little video documenting my L3 Certification Flight with the Frenzy XL on an M1297W:

[video=youtube;GQCuK-pt6Wk]https://www.youtube.com/watch?v=GQCuK-pt6Wk[/video]
 
Nice flight, Kevin. Congrats.

Don't let a little drag on the Fresno clay bother you. A 1/4 mile drag at the BR playa would probably result in a failed attempt. Cuz the playa doesn't remove paint, the playa removes fiberglass. It's like getting dragged across a 1/4 mile of 25 grit sandpaper, and can leave a foot long, 3" wide notch in the end of your a/f tube.

You can do that next year, minus the certification butterflies.
 
Congrats on your L3 Kevin, great build and flight!


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Awesome job, and congrats on the cert. on a quasi related note, has anyone tried jettisoning all but one set of shroud lines once on the ground? That would prevent the parachute from reinflating, and I think can be done from any altimeter with an aux channel? Added complexity, of course, but if it doesn't work, you just have to refinish...not quite sure how I'd implement it myself, but there are many far-smarter people here!


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Have you considered injecting fillets using a thinner epoxy (e.g. West System) mixed with chopped carbon fiber. Personally I think its much easier!
View attachment 319593
Just wondering, does the hole you drilled for the injection pose a problem when doing the fillets? Like does the epoxy sag into the hole or do you plug it flush with the body?

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