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The Blue Hole in the Red Sea is the deadliest dive site in the world

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Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#181

Post by henshao »

throw1234651234 wrote: post #166
s_dev wrote: post #142

Earlier quoted context omitted.

Other versions of this test include the last question being "Don't answer any questions". The habit the teacher was trying to impart was "read the whole paper" first before answering any questions -- particularly if there are multiple choice questions.

This is an irrational party(professor) trick that wastes everyone's time. An argument could be made for "read the (short) instructions at the start". An argument cannot be made for this. There is often very little value to skimming the entire question set before the exam.

I don't know about you, but for my tests on a curve where I might not be able to answer all the questions, doing the quick skim to answer the low hanging fruit before getting to the harder problems is a good way to make sure you don't run out of time and lose out.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#182

Post by Syonyk »

codeduck wrote: post #175
ska wrote: post #159

Earlier quoted context omitted.

> It's not actually the people riding like lunatics that manage to kill themselves on motorcycles at high rates. There are a couple of high risk groups. One is young guys with a combination of inexperience and a desire to go fast(er than conditions/skills allow). Another is older guys, often who haven't ridden for years if ever, who get into trouble. Again inexperience is a big factor in both.

Last time I looked at the numbers, the peaks were at 6 months to a year of experience riding, and the second at 3 to 4 years. The first peak being generally due to inexperience, the second to overconfidence. Lack of regular experience is definitely a contributing factor. Muscle memory has a half life.

> Muscle memory has a half life.

Indeed. This is part of why I sold one of my motorcycles - a powerful, fairly aggressive sport touring bike. It was my daily driver for about 2.5 years, and I rode it typically 7 days a week, around 1300-1500 miles a month. I knew the bike, and I had the "edge" - there was no question about what the bike was going to do. I knew it, I knew how it responded, I knew what I could ask of it. If I didn't ride for a few days, I could feel that the edge was dull when I got back on - there was just a little something missing, corners were a smidge sloppier, etc.

And I was no longer riding enough miles on that bike to keep that. I knew I was ham fisted when riding it compared to what I used to be, and I just don't put enough miles on anymore that I was able to keep it up.

I now ride the motorcycle version of a Russian tractor (one of a few Urals - sidecar rigs), and they're both entirely different from two wheels and demanding in different ways. But they don't have the sort of instant response of a sportbike either. A good sportbike does what you asked, right now. Capable of it or not, it does what you told it to do, and if that includes an unintentional wheelie, well, you did ask for it with your throttle inputs. The Urals have their own nasty handling corner cases, but are a lot more forgiving in many ways, and you really have to muscle them around at times. A subtle input gets entirely ignored.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#183

Post by Natsu »

Syonyk wrote: post #170
owenversteeg wrote: post #165

Earlier quoted context omitted.

Interesting. I'd be curious to read your thoughts on mitigating risk with general aviation. Is there a checklist somewhere of "always do these 20 things" or do you have to comb the NTSB accident records yourself?

You don't have to comb the NTSB records - they're aggregated by various groups. A lot of them involve loss of control of some form or another - typically in instrument flight conditions, often enough by someone who either doesn't have an instrument rating or is badly out of practice. A VFR only pilot in the clouds has a lifespan measured in minutes. Running out of fuel for some reason is depressingly common - and whi…

Sometimes this just makes me think that every pilot needs some IRF experience and a fuel gauge that has an alarm that says 'land now, you moron' or such.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#184

Post by codeduck »

Syonyk wrote: post #182
codeduck wrote: post #175

Earlier quoted context omitted.

Last time I looked at the numbers, the peaks were at 6 months to a year of experience riding, and the second at 3 to 4 years. The first peak being generally due to inexperience, the second to overconfidence. Lack of regular experience is definitely a contributing factor. Muscle memory has a half life.

> Muscle memory has a half life. Indeed. This is part of why I sold one of my motorcycles - a powerful, fairly aggressive sport touring bike. It was my daily driver for about 2.5 years, and I rode it typically 7 days a week, around 1300-1500 miles a month. I knew the bike, and I had the "edge" - there was no question about what the bike was going to do. I knew it, I knew how it responded, I knew what I could ask of i…

For broadly similar reasons I have a 650cc twin sports tourer. It is docile, mild mannered, and has enough reserve power at the speed limit should I need it.

I don't want or need anything more.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#186

Post by akiselev »

kubanczyk wrote: post #108

In truth, diving done right is procedures, procedures, procedures. That's why many novices and professionals suck at it. It needs boring personalities, or these that can handle boredom. I don't have to remember about the danger, I don't even have to respect the danger: if I actually go through all the steps and all the procedures, the risk is minimal. "If there was zero adrenaline, it was a dive done properly." I've…

As long as you're not flying an experimental aircraft, general aviation is naturally safer than diving. Since GA planes are aerodynamically stable and can glide, pilots (usually) have a lot more time to calm down and think through their options before the situation becomes really dangerous. Most emergencies can be resolved by identifying a flat field or calling an emergency at the nearest airport (which the FAA is encouraging pilots to do more often). Not to mention, getting a pilots license is about 10 hours of "how to fly a plane" and 30+ hours of "how to deal with emergencies" including the instructor cutting off engine power mid flight. There's a procedure for just about every situation and the most important ones are practically muscle memory by the time one receives a pilots license.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#188

Post by oh_sigh »

perilunar wrote: post #8

Wikipedia: https://en.wikipedia.org/wiki/Blue_Hole_(Red_Sea) Map: https://www.google.com.au/maps/place/Blue+Hole/@28.5722712,3...

Sigh...the wikipedia article has a picture of various memorials family members of deceased divers built at the Blue Hole. The most prominent one reads "Don't let fear stand in the way of your dreams"...isn't that exactly the wrong message? The guy whose quote that is died when he was 23 years old.

https://upload.wikimedia.org/wikipedia/commons/0/03/Blue_hol...

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#189

Post by MarkMarine »

JoeAltmaier wrote: post #106

Lots of things are dangerous. Motorcyclists I know each have a row of busted helmets in a closet. Ski long enough and you'll break something. Bicyclists die on the road every day (in America) and few give it a second thought. I wonder how diving compares to other off-track sporting activities. Does it have a worse record?

I don't know stats, but checking out the passings section of scuba board does indicate it's a fair number of people. The thing that is different about diving from bicycling or skiing is you really don't need to be physically fit to dive. It's relaxing and easy, people dive into their 70s and 80s so there are a lot of heart attacks of older people that get chocked up to diving and may just be natural causes.

Re: The Blue Hole in the Red Sea is the deadliest dive site in the world

#190

Post by Syzygies »

shellfishgene wrote: post #102
roland35 wrote: post #4

Summary: The Blue hole is a natural sinkhole off the coast of Egypt. It is very accessible, there are many beginners, and there are many unscrupulous dive guides which lead to diver depths. Some basic diving rules which when broken lead to deaths: - Not diving with a partner - Diving below the depth you should be - Diving after partying the night before - Rising back up too quickly

I think one big part of it is that tunnnel that leads out of the hole to the open ocean. Tunnels and arches to dive through magically attract divers, also for taking picures. The tunnel's ceiling is at 52-56 meters, which is exactly the depth that compressed air divers think they can risk diving to. The bottom of the tunnel however is at around 100 m, and nitrogen narcosis sometimes causes inexperienced divers to rea…

> nitrogen narcosis sometimes causes inexperienced divers to reach it

For those of us who (don't) remember the 60's, experience can take many forms. I remember reaching a depth of 100' in scuba training, and being asked to do arithmetic at a whiteboard.

"Um, ask me how I wrote my thesis..."

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