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mule.
mule.-
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mule
I have a new creation that I’m flying on Sat. Down the nose O – kit bashed PML IO. 😛
It’s 2.15 Quantum tubing, 72″ long, 3.2lb. If I calculate for a 50 fps descent on apogee deployment and about 15 fps on main, I get a 15″ drogue and heavy wt spherical 48″ main. Question is, do I really need the drogue?Other question, I would rather use a lighter, spherical 42″ that calcs at 18 fps. Is this still reasonable?
thanksstuck together before all the work….
new2hpr
Do you “need” a drogue? No, probably not. But, depending on the weight of the motor, the weight of your av-bay, and the drag of the fins, it might help keep things falling in a stable manner, rather than tumbling and tangling.
On your decent calculations, make sure you’re using the altitude of our sites. Far too often, I’ve had them come in faster than I’d liked. If you’re going to the trouble of DD, come in fast, then use a big chute at a reasonably low deployment to gently set ‘er down.
Just my $0.02
-KenChris LaPanse
I tend to use a drogue, and I also tend on the big side for my mains. The exception is my AMRAAM, but I have the largest chute I can fit in there already and it still comes down at ~24fps. If the 48″ fits without too much difficulty, I’d go with it over the 42.
I would think that a drogue would help make descent more predictable and controllable. You don’t need one, but as I said, I probably would use one.
mule
I’ve been leaning towards using one, I have plenty of room for it. I need a better 48. It’s one of those basic monster thick orange ones we get from Tim. my next nice one is a 60 w/ no hole. I could always take the center section back out of it, but it’s still too big. Oh well, if I wasn’t doing that 98mm CTI deal with Tim, I’d just get another one. Next month 😆
thanksforgot, some more teaser pics….
Need to pick up battery mount tonight, had to zip tie to fit bat.
Jeffrey Joe Hinton
Another possibility instead of a drogue – use a bright mylar streamer. Helps with the visual acquisition and then blow out the largest chute you can fit in at 1000′ and save yourself some walking.
new2hpr
Wow, how are you going to attach your harness to that eye on your fincan? That’s tight, at least with anything but a stubby motor!
-Ken
John A. Wilke
For my part, I almost never use a drogue… the only time I do is on BIG projects, and even then I often go without. I’d say I’ve probably done 100 or so dual deploy shots, and maybe used a drogue 4-6 times. I’ve never shredded a chute (from falling too fast) but I have tangled drogues a couple of times, so I tend to avoid them.
Years ago at LDRS a group of us flew a ~120# rocket 7 times on M and N motors. We never used a drogue on that porker… In the end, you have to do what you are comfortable with.
mule
Ken,
that’s an emergency eye – assuming I don’t have a threaded forward closure for this Sat….. I tied the Kevlar shock cord directly to it for now.I like the idea of a streamer better. I have some Mylar stashed somewhere.
Joe, ping Larry and remind him about this launch. I sent them an email earlier this week.
mule
new2hpr
Chris LaPanse
Jeffrey Joe Hinton
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