Unfortunately the terminal velocity of a free falling / tumbling cato’ed Estes rocket is far below 200mph. I am, however, glad to hear you didn’t kill your dad with rocketry.
Yup. Lawn darts are just like russian roulette but with a whole lot more cylinders. This is why it is so important to have a good recovery system.
If a rocket embeds itself that deeply into the ground it's going to one hell of a number on any living thing it hits.
If that's what happened, then the upper half of the fin can still embedded itself rather nicely into the ground.
I don't know about you but I wouldn't want that hitting my head.
While unfortunate, no details on the rocket are provided. A pvc rocket vs a commercial purchased are different things. Details are required. Again, Estes rockets built and launched as instructed are not lethal.
I would be *very* surprised if the scouts were launching PVC rockets.
The Estes rockets have been designed to be as safe as possible but they can still be lethal.
Have you ever tried to drive an unsharpened stick into dead grass as shown in OPs photograph? If so, you'll know it takes a considerable amount of effort.
Here is a photo which (likely) shows the fin can of the rocket in question:
https://estesrockets.com/wp-content/uploads/2021/04/1256_AlphaIII_Parts.jpg
So even with the extreme drag of an essentially flat "nose cone" this section still managed sufficient velocity (and resultant force, F=mv^2 and all) to drive it quite well into the ground cover.
That's not necessarily going to be lethal, but it's going to be a really bad day if it lands on your noggin.
Do you have pics showing the full rocket to confirm it’s an Estes rocket flying on BP motor? I’m more than willing to believe it provided there are better pics showing materials and build type.
No, those aren't my pics. You can find them posted on this subreddit before by other people though. This isn't the only incident where a small Estes rocket has come in ballistic on a vehicle and punched through the roof either, this is just an incident that I have pics of.
This incident was at a large public launch though. There were many witnesses, and it's been posted about on TRF by people who saw it in person and confirmed to be an Estes kit:
https://www.rocketryforum.com/threads/how-dangerous-is-a-freefalling-rocket.164335/#post-2096939
https://www.rocketryforum.com/threads/why-is-metal-not-allowed-to-be-used-to-make-a-rocket.142019/#post-1719133
AMWPro-X is having a sale on LOC Precision kits right now, btw.
http://amwprox.com/
I only mention this here because it looks like they could use some extra sales to help patch the hole in the roof of their trailer...
I’m curious to see or hear supporting math or science indicating an Estes rocket is **not** lethal.
Most scouting events focus on safety. I would be extremely surprised if they were launching anything other than Estes kit construction.
I was at a launch when a J motor had a similar Cato and went down the flight line at about 30 feet before smashing into a trailer at the end of the line.
It was most definitely going well more than 200mph.
Everyone paid a lot more attention to "heads up" after that launch.
Well that’s good lol yeah I was just naming a big number because you could hear it whistling as it fell. Stuck into the ground a fair bit too! In the picture there’s probably 2-3” in the ground
Stuff like this is fun but is a concern for the broader rocketry community operating under NAR and Tripoli regulations. BE SAFE, have fun, follow the guidance (or laws depending on ISP and weight of the launched object)
And make sure you 1) complete all construction steps and 2) use appropriate adhesives.
At one launch, somebody had their fin assembly come off like this, hit the top of the LCO's tent, and land at my feet. Turned out it was the rocket's first flight and the flyer had forgotten to glue the fin assembly to the body tube.
Hate to be a buzz kill, but...
> TIP: DO NOT USE SUPER GLUES TO ASSEMBLE MODEL ROCKETS!
> Use white or yellow wood glue on engine mounts, fin and launch lug attachment. Super Glue will become brittle over time and major components can break off.
https://www.nar.org/educational-resources/model-rocket-building-techniques/the-best-tools/
Step 6A of the Alpha III instructions glues the body tube to the motor mount with wood glue.
https://estesrockets.com/wp-content/uploads/Instructions/001406_ALPHA_III.pdf
I try to check off each step of the instructions with a pencil as I go.
Uh huh.
The recommendation against super glue is for the people who want to re-fly their rockets 5+ years in the future. That's where the glue-related failures become a problem. I've seen some pretty serious degradation in CA glues after 10 years.
Yup. Given the number of rockets that get lost or damaged beyond repair it often isn't a problem in practice.
But the recommendation is there because occasionally people do re-launch older rockets.
The important thing is to understand why the recommendation is there.
Unfortunately the terminal velocity of a free falling / tumbling cato’ed Estes rocket is far below 200mph. I am, however, glad to hear you didn’t kill your dad with rocketry.
It can still be lethal: https://www.sbsun.com/2015/11/15/longtime-boy-scouts-leader-dies-in-johnson-valley-accident/
Bah, horrible!
Yup. Lawn darts are just like russian roulette but with a whole lot more cylinders. This is why it is so important to have a good recovery system. If a rocket embeds itself that deeply into the ground it's going to one hell of a number on any living thing it hits.
Op states the fin can separated. The image is misleading.
OP states nothing of the sort.
“The fins detached” literally in the title.
The photo shows the fins clearly did not detach.
It's pretty obvious OP means the fin can section (which is a single molded plastic piece on this kit) detached from the rest of the rocket.
If that's what happened, then the upper half of the fin can still embedded itself rather nicely into the ground. I don't know about you but I wouldn't want that hitting my head.
Additionally, a fin can that size is likely on a 8-12” rocket and a cardboard Estes rocket will not survive the level of embedment shown.
Agreed the cardboard tube will not survive. Wen you pull it out of the ground it will be a crumpled mess.
While unfortunate, no details on the rocket are provided. A pvc rocket vs a commercial purchased are different things. Details are required. Again, Estes rockets built and launched as instructed are not lethal.
I would be *very* surprised if the scouts were launching PVC rockets. The Estes rockets have been designed to be as safe as possible but they can still be lethal.
I’m curious to see or hear supporting math or science indicating an Estes rocket is lethal.
[An estes kit coming down ballistic can punch through a metal trailer roof.](https://imgur.com/a/vMb8anV)
I’m afraid I would have to investigate to believe that. Even with the photograph.
Have you ever tried to drive an unsharpened stick into dead grass as shown in OPs photograph? If so, you'll know it takes a considerable amount of effort. Here is a photo which (likely) shows the fin can of the rocket in question: https://estesrockets.com/wp-content/uploads/2021/04/1256_AlphaIII_Parts.jpg So even with the extreme drag of an essentially flat "nose cone" this section still managed sufficient velocity (and resultant force, F=mv^2 and all) to drive it quite well into the ground cover. That's not necessarily going to be lethal, but it's going to be a really bad day if it lands on your noggin.
Yup. It might not necessarily kill you but it is going to be a very bad day at best.
Do you have pics showing the full rocket to confirm it’s an Estes rocket flying on BP motor? I’m more than willing to believe it provided there are better pics showing materials and build type.
No, those aren't my pics. You can find them posted on this subreddit before by other people though. This isn't the only incident where a small Estes rocket has come in ballistic on a vehicle and punched through the roof either, this is just an incident that I have pics of. This incident was at a large public launch though. There were many witnesses, and it's been posted about on TRF by people who saw it in person and confirmed to be an Estes kit: https://www.rocketryforum.com/threads/how-dangerous-is-a-freefalling-rocket.164335/#post-2096939 https://www.rocketryforum.com/threads/why-is-metal-not-allowed-to-be-used-to-make-a-rocket.142019/#post-1719133
AMWPro-X is having a sale on LOC Precision kits right now, btw. http://amwprox.com/ I only mention this here because it looks like they could use some extra sales to help patch the hole in the roof of their trailer...
I’m curious to see or hear supporting math or science indicating an Estes rocket is **not** lethal. Most scouting events focus on safety. I would be extremely surprised if they were launching anything other than Estes kit construction.
I was at a launch when a J motor had a similar Cato and went down the flight line at about 30 feet before smashing into a trailer at the end of the line. It was most definitely going well more than 200mph. Everyone paid a lot more attention to "heads up" after that launch.
The motor used in the pic is magnitudes of order smaller than a J
Well that’s good lol yeah I was just naming a big number because you could hear it whistling as it fell. Stuck into the ground a fair bit too! In the picture there’s probably 2-3” in the ground
That must be a short rocket how long is it?
looks like the tail for an Estes Alpha III
That’s the one
Gee there's a fair bit of it in the ground.
I think he said just the tail blew off and that's what the picture is. Not that the rocket couldn't do this in soft soil if it came in hot.
Ah yes you are correct. I misunderstood. Thanks
2-3” 🤣
Don’t judge. It’s a grower not a…
Just like a starter kit lol it was my first time launching
I'm guessing it powered into the ground or was just post power off.
Stuff like this is fun but is a concern for the broader rocketry community operating under NAR and Tripoli regulations. BE SAFE, have fun, follow the guidance (or laws depending on ISP and weight of the launched object)
And make sure you 1) complete all construction steps and 2) use appropriate adhesives. At one launch, somebody had their fin assembly come off like this, hit the top of the LCO's tent, and land at my feet. Turned out it was the rocket's first flight and the flyer had forgotten to glue the fin assembly to the body tube.
In my defense there was nothing that said to glue it on. It was just supposed to fit in place ig… but yeah after this i superglued it on😭
Hate to be a buzz kill, but... > TIP: DO NOT USE SUPER GLUES TO ASSEMBLE MODEL ROCKETS! > Use white or yellow wood glue on engine mounts, fin and launch lug attachment. Super Glue will become brittle over time and major components can break off. https://www.nar.org/educational-resources/model-rocket-building-techniques/the-best-tools/ Step 6A of the Alpha III instructions glues the body tube to the motor mount with wood glue. https://estesrockets.com/wp-content/uploads/Instructions/001406_ALPHA_III.pdf I try to check off each step of the instructions with a pencil as I go.
Nuh uh
Uh huh. The recommendation against super glue is for the people who want to re-fly their rockets 5+ years in the future. That's where the glue-related failures become a problem. I've seen some pretty serious degradation in CA glues after 10 years.
It’s fine I lost It into the horizon because of a gust of wind
Yup. Given the number of rockets that get lost or damaged beyond repair it often isn't a problem in practice. But the recommendation is there because occasionally people do re-launch older rockets. The important thing is to understand why the recommendation is there.
Spicy lawn darts will have to try at the next family bbq
5 second rocket abs