level 1 attempt. Could use a little help w/sims
- Thread starter Wallace
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Thanks for the plugs guys... I can't help with the older machine, but I'm fair to middling with getting OR to do what you want (provided you have a working copy).
well I've managed to at least get close to what I suspect will work. My current thoughts are; Go for cert w/H115 DM using motor eject single deploy with 26" hemi chute (with generous spill hole) while not losing it, hopefully all goes as planned, gain said certification then punch it with an I205 W along with my yet to be completed/tested cable cutter setup and 30"hemi set to deploy around 600' and hope the eggfinder and my hiking boots are up to the task. Is good plan no?
View attachment Estes Scion(3).ork
View attachment Estes Scion(3).ork
If it were me, I'd do the cert flight as you suggested, then test the cable cutter set up on a similar motor. Lower altitude means you can verify the process works before sending it to the moon.
Have you used the eggfinder before?
Only basically toyed with it. I tried google maps, US topo maps and I do have a Garmin Etrex handheld. Once again, I absolutely need to find time beforehand to get out and do some testing. I have some F and some G motors for said. Any and all advice is much appreciated...
Charles_McG
Ciderwright
I find a simple range and bearing app on the phone, manually typing the coordinates from the receiver into the app, is easy, cheap, and straightforward.
At Bong, there is cell coverage, so you can do maps. Which can be handy to spot the ponds -before- wading into them (djs), or to figure out the roads to the farm fields to the south.
I'm set up to BT the eggreceiver data stream to my Surface, but I haven't done it in the field yet.
I'll second the advice to save the cable cutter until you practice with it on lower flights. They aren't as simple/reliable as they seem. Get over the learning curve first.
I did my L1 two launches ago at Bong, with DJS witnessing, on a nearly stock built Estes PSII Leviathan (fin fillets bigger than instructions) and an H175SS. A much lighter build than yours, but otherwise similar.
At Bong, there is cell coverage, so you can do maps. Which can be handy to spot the ponds -before- wading into them (djs), or to figure out the roads to the farm fields to the south.
I'm set up to BT the eggreceiver data stream to my Surface, but I haven't done it in the field yet.
I'll second the advice to save the cable cutter until you practice with it on lower flights. They aren't as simple/reliable as they seem. Get over the learning curve first.
I did my L1 two launches ago at Bong, with DJS witnessing, on a nearly stock built Estes PSII Leviathan (fin fillets bigger than instructions) and an H175SS. A much lighter build than yours, but otherwise similar.
Oh- I knew where the ponds were.. I went any way.
Charles_McG
Ciderwright
So, do you ever stop and watch the snapping turtles crossing 142 in the spring?
My thought process was more like:
"Hey this is pretty deep"
"Guess I have to swim"
"OK, I can walk now"
"Hey these weeds are thick"
"are there water moccasins in Wisconsin?"
"Would I see one before it bit me?"
"I bet those bites are painful"
"How far is it to the nearest place with anti-venom?"
"Do snakes like to hide in the reeds?"
"They're more afraid of you than you are of them, right?"
"Would a snake see me and slither away before I see them?"
"Was that a frog or a snake?"
...etc.. you get the point
Charles_McG
Ciderwright
DJS, no water moccasins in WI. Timber rattlers along the Mississippi. Massasauga along the southern border, including Kenosha County - but they are so rare they are listed as endangered in WI, and like river floodplains better than land locked swamps, anyway.
I've always wondered what would happen if one stepped on a snapping turtle. Some are big enough to stand on. And bite through at least 29mm airframe
I've always wondered what would happen if one stepped on a snapping turtle. Some are big enough to stand on. And bite through at least 29mm airframe
Charles_McG
Ciderwright
The Quark tending the chute chirped out 1799'. 100' short of the sim.
It landed to the south of the pool along the drive. About 800' from the A pads.
It had a sonic locator in it, along with the Quark. But it was eyeball otherwise.
It landed to the south of the pool along the drive. About 800' from the A pads.
It had a sonic locator in it, along with the Quark. But it was eyeball otherwise.
Charles_McG
Ciderwright
The Quark was set to release the chute at 300'. Motor ejection only.
Charles_McG
Ciderwright
KBUU weather history suggests the wind was 10-15mph.
So some sort of cable tie chute reefing cuttter burner setup then? I just can't see deploying a main at 1700' as "keeping it simple". Please correct me if I'm wrong but that seems to add, not mitigate risk. While I'm on my rant, what difference is there in a core sample from 1500' as opposed to a core sample from 3000'? Potentially less digging? Sorry, just read that and it kinda sounds like I'm being an ass. Not my intent, just need to know. Thank you all for being so helpfull.
@Wallace- these are fair questions. As the person who signed off on Charles' L1 cert, I can answer with my reasoning:
1. Main at apogee with no electronics is the lowest point of failure. Still some failure modes, but less complex than other topics
2. Charles' chute tender has the chute come out at 300', but the chute itself (reefed) comes out at apogee (with motor eject). This helps mitigate the most dangerous recovery- lawn darting.
3. Charles has flown this chute tender before on F+G motors, so I knew that the functionality had been proven to work (most of the time), and he was familiar with recovery from a higher altitude.
4. Charles has flown this particular rocket before on smaller motors, so I knew that it had a history of being structurally sound.
With that being said, I still examined the rocket before going ahead with the flight. In my experience, most L1 failures are due to airframe or stability failures- rockets shredding or skywriting. Second to this is "no chute". Generally with the second, it's in some ways less dangerous because the rocket has ejected it's nose cone, but the chute is stuck in there. At this point, the flight path is mostly known and predictable. With the first, you don't know what the rocket will do (or pieces of the rocket will do), which makes it more dangerous.
1. Main at apogee with no electronics is the lowest point of failure. Still some failure modes, but less complex than other topics
2. Charles' chute tender has the chute come out at 300', but the chute itself (reefed) comes out at apogee (with motor eject). This helps mitigate the most dangerous recovery- lawn darting.
3. Charles has flown this chute tender before on F+G motors, so I knew that the functionality had been proven to work (most of the time), and he was familiar with recovery from a higher altitude.
4. Charles has flown this particular rocket before on smaller motors, so I knew that it had a history of being structurally sound.
With that being said, I still examined the rocket before going ahead with the flight. In my experience, most L1 failures are due to airframe or stability failures- rockets shredding or skywriting. Second to this is "no chute". Generally with the second, it's in some ways less dangerous because the rocket has ejected it's nose cone, but the chute is stuck in there. At this point, the flight path is mostly known and predictable. With the first, you don't know what the rocket will do (or pieces of the rocket will do), which makes it more dangerous.
Charles_McG
Ciderwright
Yes, a nichrome wire cutting a fishing line keeping a rubber band tight around the chute bundle. But probably my 8-10th flight of it, so not trying it out on a cert flight.
My son did his L1-jr on a Wildman Sport/H163 at Bong. Apogee deploy, small chute, visual tracking, no locator. Mechanically simpler - longer walk.
There's no difference between a 3000/1500' core sample. And there may not be a difference between the tall fall lawn dart, and the core sample draped by a chute shredded by a 500' deploy at free fall speed. Apogee deployment is -the- most critical recovery event. Late deployment -might- be survivable. But only maybe. Drogue-only deployment is far more survivable.
My Leviathan is so lightly built, it really doesn't need the chute to unfurl, as long as the nose comes off. If my chute tender failed, the rocket's light enough to make the landing anyway. My sim says 590g empty.
Your rocket's heavier - you'll want a bigger chute. Which means if you want to limit drift, you'll need to tend that chute. You might want to practice with some Gs before the cert flight.
Or use the lighter nosecone and a smaller chute. If it deploys high, well that failure mode means a longer walk, maybe longer search. But not a failed cert flight.
My son did his L1-jr on a Wildman Sport/H163 at Bong. Apogee deploy, small chute, visual tracking, no locator. Mechanically simpler - longer walk.
There's no difference between a 3000/1500' core sample. And there may not be a difference between the tall fall lawn dart, and the core sample draped by a chute shredded by a 500' deploy at free fall speed. Apogee deployment is -the- most critical recovery event. Late deployment -might- be survivable. But only maybe. Drogue-only deployment is far more survivable.
My Leviathan is so lightly built, it really doesn't need the chute to unfurl, as long as the nose comes off. If my chute tender failed, the rocket's light enough to make the landing anyway. My sim says 590g empty.
Your rocket's heavier - you'll want a bigger chute. Which means if you want to limit drift, you'll need to tend that chute. You might want to practice with some Gs before the cert flight.
Or use the lighter nosecone and a smaller chute. If it deploys high, well that failure mode means a longer walk, maybe longer search. But not a failed cert flight.
Charles_McG
Ciderwright
Looking back at your last post:
Apogee eject and deploy is -mechanically- simplest. But increases the drift distance. That -might- raise the risk of loosing the rocket. No rocket back at the table, no cert. I can see your concern.
I think you're looking at the risk of not being to find your rocket at all, while we are noting the risk of added electronics and mechanics failing and leading to structural damage to the rocket.
At some level, there is risk in flying. We work to mitigate it. I've recovered enough rockets from the tall weeds at Bong that drift is not the risk I weigh heaviest.
Apogee eject and deploy is -mechanically- simplest. But increases the drift distance. That -might- raise the risk of loosing the rocket. No rocket back at the table, no cert. I can see your concern.
I think you're looking at the risk of not being to find your rocket at all, while we are noting the risk of added electronics and mechanics failing and leading to structural damage to the rocket.
At some level, there is risk in flying. We work to mitigate it. I've recovered enough rockets from the tall weeds at Bong that drift is not the risk I weigh heaviest.
Agreed- to me the highest risk is having a rocket be in a dangerous situation where someone could get hurt. This should always be the first risk to mitigate.
Ok; I guess I failed to properly explain my intent. I have several simlar hot wire/igniter type reefing systems, all partially completed. That was my original intent; use motor eject to kick out the bundle and let the quantum release it at a reasonable height. I also have a quark that would either fit in my bay or if not, tape to the harness for redundancy. I know, I get it, I just ADDDED complexity but I promise I won't even attempt it untill I have at least a couple of successful mid power flights on whatever I decice to go with. Good point on the weight of mine compared to yours, totally missed that one....While I'm at it, do you guys require a mechanical switchw/a quantum? I won't have any pyro on board with the exception of possibly an igniter for a burn string...
Charles_McG
Ciderwright
Here's a tip, rather than a lecture: use enough thrust. If you cut through the wind and fly straight, it hardly matters how windy it was. Tip the rod into the wind, get a straight flight, let the wind carry the rocket back to you.
The longest recoveries I've had, or seen, typically share a flight that went cross-range, rather than down-range. Or way-way downrange, rather than up. Then you hit trees and corn fields and swamps and all kinds of unpleasantness.
BTW - I find that the bound up chute bundles make for a squirrelly downward leg. The rocket body has a tendency to back-glide - and drifts back and forth cross-range. I don't know if drogue-chute bay combos are any less prone to that.
The longest recoveries I've had, or seen, typically share a flight that went cross-range, rather than down-range. Or way-way downrange, rather than up. Then you hit trees and corn fields and swamps and all kinds of unpleasantness.
BTW - I find that the bound up chute bundles make for a squirrelly downward leg. The rocket body has a tendency to back-glide - and drifts back and forth cross-range. I don't know if drogue-chute bay combos are any less prone to that.
I will show up fully prepared option wise (several potential combinations and maybe a spare rocket or two). I fully understand where you're coming from, safety being the biggest concern. Who can say, I may just lose or destroy my Scion during testing, that's always a possibility. If that happens I'll bring something else. I suspect you won't dislike whatever it is I show up with....
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Just in case anyone is interested; This is of which I spoke in regards to chute sizes up to 60". $4.99 golf umbrella @ Home Depot. Pretty nice nylon of some Chinese sort, full 60" canopy weighs 2.7 ounces. Always cut w/hot knife or you'll regret it. Simple way to make hem is hem tape, just fold and iron. Shroud lines get sewn on in any manner you chose or even take the lazy path and poke & tie (again, use the hot knife). Custom lightweight himispherical chute for well under $10 in about an hour along with the satisfaction of have done at least part of it yourself.
I guess that might be a good plan, but I would suggest building 38mm MMT rocket you can use all the L1 motors in and still land on your field. If that means a 6 lb. 4" diameter or a 3 lb. 2.6" diameter is to be determined. Either way, build something that you can fly L1 motors in without risking loosing it on every flight. That's why you're getting a L1 cert for in the first place. Once you learn to fly the field with a 3g 29mm to a 6g 38mm you will be ready for L2.
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