pilotdave

According to the article, she'll be doing 1150 km/hr, which equals about 1048 feet per second. The speed of sound at sea level, in standard atmospheric conditions, is 1116.4 ft/s. I don't know what altitude she'll reach terminal velocity, but it says she'll start to slow down at 100,000, so lets assume that's where she hits terminal. The speed of sound at that altitude (in a standard atmosphere) is 1003.2 ft/s. She'll be supersonic. Anything moving supersonic, or in fact transonic (where the speed is subsonic but some of the flow around the object is supersonic), will create shockwaves. A sonic boom is nothing more than what you hear when a shockwave enters your ear. Nobody will hear her shockwave because a shockwave forms in a cone shape. Falling straight toward the ground, the cone will face the ground, pointy side down. You'd have to be next to her for the shockwave to pass over you. A plane creates a sonic boom because it's flying horizontally. The shockwave passes over the ground. edit: The speed of sound does NOT depend on air pressure. It depends on some properties of air (which change with the composition and density of the air, which changes with altitude) and temperature. As temperature decreases, speed of sound also decreases. For the most part, up to 100,000 feet, the speed of sound decreases with altitude. Dave

Anything going supersonic will create a sonic boom... but you won't be able to hear it unless she passes you in freefall. The shockwaves won't reach the ground. Dave

White is the color of an expert. Non-experts don't wear white, they wear pre-brown. Dave

Here's the question. Is skydiving portrayed any worse than the rest of the sports shown on that program? Yeah, of course they dramatize it and show that they have no clue what's really going on, but I bet they do that for every clip they show. This isn't just a skydiving phenomenon. Shows like RealTV or the scary video shows on TLC try to make EVERYTHING more exciting than it really is. How many times do they show car racing crashes? Do you think they hire consultants to determine the actual cause of the crash? No, they just say "something went terribly wrong and..." Skydiving isn't a sport the majority of the world is ever going to understand. Don't let that bother you. Laugh at their mistakes. Dave

Yeah, a 20% off coupon is usually useless for a container or main. Great for a jumpsuit though! I got 25% off my Bev Suit that way. With options, it still came out below base price. Dave

This is why I don't jump with a hook knife. I doubt I'd have any clue what to do with it even if I needed it. Ok, I realize you aren't telling us not to bother with hook knives, and I'm actually getting one with my new container in a few more months (hey arlo, HAS IT BEEN 14 WEEKS YET???). It's just not something I've ever thought of as required or very important equipment for the jumping I do. Dave

No, just set it to zero when you get there. All you're doing is moving the needle, not the internal stuff, so theres no way to do it wrong. Dave

USPA says 16 is the minimum age with parental consent. Dave

Tremors! (With Kevin Bacon). One of my favorite movies. Nobody believes me when I tell them that. Dave

When visiting the US Army Aeromedical Research Lab a few months ago, I saw a lab where they test medical equipment for use on aircraft. I saw a really cool stretcher designed for the army, which had almost every piece of emergency medical equipment you could need built right in. Everything from a heart monitor to a defribulator. It could basically turn any vehicle or helicopter into an ambulance. But the army rejected the idea. Why? It weighed too much. A female medic only has to be able to lift 60 lbs. Two female medics can't even carry one average size soldier. THAT is messed up. I have no problem with women in the military as long as they are capable of doing their job. If you can only lift 60 lbs, whether you are male or female, DON'T BE A MEDIC! Dave

Ok, well the format is still the same... "='C:\path\[filename.xls]sheetname'!$G$9" Be sure to use those single quotes surrounding the path to the sheet name when you're using a whole path in the reference. Dave

I honestly don't think that reading about incidents is what stops the average person from jumping out of a plane. There are those that would and those that won't, regardless of how accidents are portrayed in the media. The "those that would" group is then split up among those that can afford it, and those that can't. So yeah, some positive articles instead of negative ones could get some new jumpers, and a few people that read about a horrible death might choose not to jump because of it, but overall I don't think either group could be the cause or prevention of skydiving becoming a mainstream sport. edit: no matter how balanced the account is, death is death. Dave

Do it the same way I suggested before. Lets say you want data from Book1 to appear on Book2. Go to the cell you want to put the data on book2. Type "=". Then go to Book1, find the cell you want to take data from, and click on it. Then press enter. Your cell in book2 will now contain: =[Book1]Sheet1!$A$1 (or whatever the book is called and the selected cells are). Dave

It's down till... umm.. it's back up. Seriously considering paying for professional hosting, which comes with a 99.9% uptime guarantee. That would be nice, wouldn't it?

Skateboarding, mountain biking, inline skating, skiing, snowboarding are all easy to sell compared to skydiving. Get some cool looking skateboards in a store, and you've got an instant market of new skateboarders. You can't do the same with skydiving gear. I think you're right that skydiving could become more popular if more people were exposed to it (how many of you have friends that have made at least one jump because they know you?), but it'll never make it as a "mainstream extreme" sport. There just isn't the market. Dave

Easiest way is to just enter = in the destination cell, then go click on the cell you want to take data from. It'll give you the correct wording that way. Dave

It's all just a matter of money. Skydiving does have a limited audience. You'll never see a magazine like parachutist on newsstands because very few people would ever buy it. And who would take out ads in a skydiving magazine being sold to non-skydivers? Those other "extreme sports" that get more attention are also MUCH more popular. The books and magazines exist because they're more popular, not the other way around. It surprises me you can find magazines like Flying and Plane and Pilot in some bookstores, but at least flying is something a lot more people have an interest in, and there are plenty of ads for non-pilot products like fancy watches and cars. Dave

Video is temporarily available HERE. Dave

Sounds like this sport's too easy for ya!

I'm guessing stiffer, energy absobing foam would be less comfortable during everyday use and for light hits. Besides, without the proper shell to hold it, I don't think you can be sure changing the foam would make all that big a difference. I'm sure someone will design a "crashworthy" skydiving helmet someday, but I don't think a small modification to an existing helmet is gonna do it. I'd love to see some testing done on our helmets though. They're not designed for large impacts, but I bet some hold up better than others. I wonder about the hardware on top of the bonehead havoc for example... a hit to that part could really focus the energy. Probably the same thing with the hinge hardware on most other helmets. Dave

Guy I work with had it. He had gotten a flu shot too, but he got the other strain. Went to the hospital and was told he had the worst case they have seen all season so far. He came back to work today. I REALLY hope he was all better. Dave

I stuck with an F111 canopy loaded at around .85 until I had over 100 jumps (just recently got my sabre2 loaded at just over 1.0). My old canopy was slow, but it was ALWAYS fun for me. Couldn't dive like my sabre2 does now, but it could still spiral and pull some Gs. But it always kept me out of trouble, and was simple and easy to fly. I really wasn't planning to downsize until I demoed a sabre2 (actually demoed a javelin that had a sabre2 in it), and learned that I'm a fan of ZP.

Not on the moon. Dave

What's the rush to downsize? Spectre170 not fun enough for ya? Dave

How will pulling rear risers lower your angle of attack? Dave