uer16

Doesn't sound that impressive

That was a bit of a hyperbole. Not sure how it is in Germany, but basic gear maintenance is part of getting an A-license here. So the D224 risers don't come with hard housings installed? I assumed they already had them. Thanks for the suggestion, this is probably what will end up happening.

Sorry I wasn't clear. The velcro and toggles are fine, it seems to have been replaced at some point. The risers themselves are worn (especially where the harness ring loads the ty-17 webbing, and the white loop). Are paragear D224 velcro risers? I like how secure velcro is, hence why I'm looking for the out-of-fashion risers.

Does anyone still make those? I love mine, but they're worn to shit, don't have hard housings and need to be replaced.

https://www.youtube.com/watch?feature=player_embedded&v=ODhBajI4JaI Should be required viewing to whoever thinks that yelling CUTAWAYY at a bunch of people is a good idea. To be fair, the guy apparently was a lieutenant colonel, and in true military style, he executed the order immediately without thinking. Moreover, the guy on the ground was yelling at a cutaway'd canopy that was spinning, not a person, which makes the whole thing even more ridiculous.

A day or 2 later: http://s010.radikal.ru/i314/1103/79/2fbdd5f2a271.jpg

Most of the time that's not a very accurate method. Very good batteries (like Maxell) maintain rated voltage regardless of them being at 5% or 95% capacity. You can't determine anything useful from a voltage measurement. If the voltage does drop substantially as they are drained (Panasonic ones do, for example), then you can load them at rated load (15k ohm for Panasonic) and measure voltage at one of the temperatures that the cell was tested at (-10C, 20C, or 60C). Then try to match the measured voltage to the discharge curve from the datasheet. Basically too much work to be worth it. Best bet is to just replace them every X amount of hours, they're basically free compared to jump tickets anyways.

Unless they are fake batteries. I bought a few Chinese 6000mAh 18650 cells once, after characterizing one of them at rated current, the capacity turned out to only be around 250mAh. Not sure if there's a large market for fake coin cells, but it's certainly a possibility. Regarding performance, Maxell's CR2032 datasheet suggests that they have the flattest discharge curve of all, staying at 3V till the very end.

Specifically, what kind of material is the standard kill line made of and where can one get some?

While we're on topic, what recommendations are there regarding the material? (I.e. what kind of Spectra is it by default, and what can it be substituted with). Specific example: I have 400lb Dacron and 725lb Spectra, would either of these work? Both seem to be around 2x the bulk of whatever is in the PC.

It's been my (limited) experience that even though AADs might be listed here as "not required", the DZO may not nessecarily allow you to jump without one. 100% understandeable imo, but something to keep in mind.

$494.47 per jump!?

Last year I made one with a 7-segment LED display, which, even though it was the brightest on the market, was too dim in the sun. And at 100mA current draw, the battery couldn't last a day. I'm now interested in making one with a big 2.7" Sharp Memory display. Will work on the hardware over the next couple months, will let you know of the progress. Software-wise, writing render code for the 400×240 (or any other really) display would be a first for me, so help would definitely be appreciated. I'll put all the stuff in a bitbucket repo and link it later here.

I meant a hinge-type microSD holder inside the device (i.e. you can't take the card out without taking the device apart). Basically as an alternative to on-board memories. The bigger issue with making it water-resistant is probably the membrane for the pressure sensor(s).

I've used the MPL3115A2 with great success, has internal temperature compensation and altitude calculation, simplifies firmware a bit. The SCP1000 seems obsolete as of now. And +1 to whatever Gary said, implementation details like what exact hardware to use aren't that important. There's also no point in limiting the amount of sensors for the initial device for data acquisition. I'd go with a gyro, an accelerometer, magnetometer, an altimeter or 2 (which includes a temp. sensor internally), and perhaps even GPS, although this one would severely constrain a bunch of stuff like battery and case size. And also slap a microSD holder for logging all the stuff, since eeprom/flash or whatever ICs have worse byte/$ ratio than an SD card and are easier to use. And data can be retrieved from a broken device this way too. Something like an N3 with all of the above sounds pretty interesting.

I was talking specifically about a one-off prototype, which I have some experience with. I have 0 experience with large-scale production and agree that thAt is probably neither trivial or easy.

I'm willing to put time into it. Reverse-engineering is a waste of time, especially with the old cypres with its' external ADC and other obsolete stuff. Designing from scratch is complex, but mostly trivial. Anyone who knows C and can read a manual can follow MIRSA-C or the shorter JPL standard. PCBs are $5 per square inch nowadays, i.e. basically free. Machining an enclosure is free if you have access to a shop. Really, the only thing that one can't make themselves is the cutter. In any case, a prototype would run at most a couple grand with the above, large-ish scale production is a completely different story though. Imo, the regulatory and validation issues are bigger than the technical ones. (i.e. who will let me, or anyone else test-jump, or maybe drop-test a homebrew AAD?). In reality, starting with something a bit less serious like an open source altimeter that would integrate AAD code to watch for inadvertent fires would probably be a good first step to see how it goes. Basically a risk-free test platform. Actually that sounds like a good winter project, any volunteers to test-jump one-of-a-kind altimeters?

Did my static line course here. The instruction is absolutely fantastic, very student-oriented. They make sure their students become good and safe skydivers. Unfortunately the student program is closing down due to lack of landing area, but it was great while it lasted. Awesome friendly atmosphere, people will jump with you regardless of how much you suck at RW, and will help you out with whatever skills you need. Lots of fun is to be had here, high pulls, tracking dives, CReW, whatever you want (minus wingsuits). Caravan full? no problem, there's almost always space on the fun-82 which will go up with as little as 2 people. Rental gear is brand-spanking-new, and seems that they like to keep it that way. Staff is always super helpful. This is the one and only DZ I can call home. Can't wait to get my C and be back for more.

Disclaimer: I'm a traveling A-licensed newbie jumper with 100+ jumps, without own gear. My experience may not apply to you, take the review with a grain of salt. After showing A card + logbook, went to get rental gear. Lady consulted the trusty Brian Germain's WL chart plastered on the wall, and decided to put me under a 200 sq. ft. canopy (I'm 150lb mind you). After a bit of talking and showing her that the majority of my jumps were under a 170, she finally let me jump a 170. At the boarding area. I feel some movement on my back: some guy I've never seen before decided to mess around with my flaps, without any warning, let alone asking. He was giving a gear check apparently. I was so full of rage I could not talk, and was only able to give a death stare. After plane arrived on a hot-load we had to wait >10m for the TMs to arrive (their students were waiting too). In the plane I get chewed out for not having a jumpsuit (i.e. my tight fitting shirt that is pulled through the legstraps will somehow get over my handles and I will instantly die). Get my rig molested again in the plane, this time with a heads-up, but without asking if I actually WANT a gear check or not. Quoting the head honcho, "This is my dropzone and nobody will get hurt here under my supervision". This came off as arrogant, holier-than-thou attitude. People will get hurt eventually, doesn't matter how much you try to prevent that. I jump for fun, and I did not have any at Parachute Montreal, this experience left me with a bitter taste in my mouth. Also a lot poorer after $70 jump tickets. Regardless of my experience, this might still be a good place for the average skydiver. Awesome plane that climbs quick. Nice, big, green, segregated landing area with plenty of wind indication and targets.

Man this is funny. "A is better than B because facts" "what facts?" "Google it" Unless both companies give away all the C code/hardware design/mechanical design to a 3rd party for analysis all this yelling is senseless and feels like brand loyalty for subjective reasons. Nobody outside the manufacturer (potentially not even) will ever really know what is going on inside an AAD's brain, and seems like people can't make peace with that. Besides, describing an AAD as "safety critical" is doing a disservice to it's users imho. It's a consumer electronics device that's made to consumer electronics standards, just like your shitty iPhone. It's not like this crap is certified to DO-178/DO-254/IPC610-class 3, etc... Wouldn't it be nice if someone made an open-source (both software AND hardware AND mechanical design) AAD, so when it inevitably malfunctions, everyone can take a look at the design and see exactly where it went wrong. And fix it. // end rant

Might have something like this as Lee suggested: https://www.apexbase.com/harness-containers/apex-dpx-expandable

Heh, I believe that . Thanks for going through all the questions, pretty rare nowadays to see the engineers that involved with end users.

Finally found a perfect rig for the right price. Was sent out on the 24th of July. A week later it did not arrive (last known location was warehouse 10m away from destination ) and got reported as lost by the shipper. 3 days later it surfaces literally on the opposite end of the U S of A. Fine I think, shit happens, can wait an extra week. Another week goes by and it shows up at the final warehouse. Happy knowing I'll get it soon, right? Wrong, these fucks have lost it again the second time at the exact same warehouse. It's now been a total of 3 weeks since shipment and UPS has no idea where it is. When I called they basically told me to fuck off and refused to give out any info (let alone take any action) since I'm not the shipper. Fuck UPS

Now that reminds me (was a while ago). I didn't actually sew any zippers, but was planning originally. I sewed the side and bottom flaps together on both reserve and main (was awkward due to stiffeners). Put 3 fastex clips on top main flap, and one clip on the top reserve flap. Then cut off the legstraps without replacing the heavy webbing. Basically exactly like you're describing. It can probably be done to look nice, if one has skill/talent (I don't). Also, not sure how one would put a rig on with no legstraps, but then again, people jumped after forgetting to put a rig on at all ..