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frogfish

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Everything posted by frogfish

  1. My problem comes with "raise the alarm" and "used by search & rescue to locate you". Let's just say, hypothetically, that one is using this unit in a location like Komodo (the recent incident) or Raja Empat in Indonesia. My understanding is that there is no reliable arrangements or system yet in place whereby the "alarm" raised when a satellite picks up the 406 MHz signal is passed on to a local who would, in theory, carry out the search & rescue operations. Similarly, I'm not aware that any organization or service in Indonesia that might be carrying out search and rescue operations in these locations - say National Park rangers in Komodo, Forest Police in other Indonesian national parks, water police, police, or local military units have receivers capable of homing in on the 121.5 MHz homing signal. If so, then carrying a unit like this in places like Indonesia would be a waste of time or worse, if the equipment were actually relied on as a substitute for conventional visual signalling devices. And I assume the situation would be the same in PNG, the Solomons, and possibly also the Philippines. I'd love to be wrong about this, and if so - I really hope there is somebody knowledgeable out there who can set me straight. Pending solid information, I think the assumption that equipment like this - which may indeed be very useful in alerting SAR teams in places like California or Florida - would have any value in countries such as Indonesia or PNG may be a risky one. Frogfish (who is sticking with a 10' SMB and marine emergency dye packs for now)
  2. An update from PNK on the missing divers... Holding Statement: 7pm, Bali time, Saturday, June 7 2008 Successful Search and Rescue Operation Demonstrate Power Of Cooperation as Strong as Ocean Current The five divers reported missing in Komodo National Park on Thursday evening are recuperating, from the effects of sunburn and dehydration only, in a Labuan Bajo hospital tonight after being rescued just before lunch time today (local time) by PT. Putri Naga Komodo’s speedboat, Cakalang, part of massive search and rescue efforts involving all the major stakeholders in the Park. Today, the recognition of a job, collectively, well done has sparked a current of emotion ­ as powerful and full of direction, if you will, as any ocean current running through the Park – that gives light to a simple but irrefutable fact: anything is possible when we work together. As anyone who has ever dived in Komodo National Park knows, the waters there are home to an extraordinary abundance of spectacular and diverse marine life. But it also harbors its dangers: some of the swiftest and most unpredictable currents and undertows on the planet. Ironically, the latter is at least partly responsible for the former. Soon after the divers were reported missing, PNK staff Pipin consulted Greg Heighes and Jos Pet, well known members of the local dive and live-aboard community that were so instrumental in the SAR efforts, for their considered advice on the currents. After consulting local tide tables and using their knowledge of the dive conditions, the two were able to accurately pinpoint where the currents might have swept the divers to: South Komodo island. This information was quickly transmitted to Salim, the captain of the PNK speedboat Cakalang – also aboard Suhar-ABK, Saleh, Zaenudin and Hasbin (The Komodo National Park Authority), BTNK- Vinsensius Latief, Ramanag Ishaka, Yoseph Nong SH. Urbanus Sius (Park Authority) and Abu Bakar Pasha (PNK) - which began its search yesterday in the area where today it plucked the five lucky divers off a south Komodo beach. Says Rili Djohani, President Director of PNK: “Komodo National Park’s size, climate and fierce currents mean that cooperation and collaboration are really essential to the success of any search and rescue effort. Today’s very happy ending illustrates that. “It also serves as a powerful reminder to those of us working to protect and preserve this very special place, that, truly, you can achieve anything if you stand united. By drawing on the resources and capabilities of the government, the park authority, the private sector and volunteers, we, collectively, achieved something great and the current of good will flowing through all stakeholders today bodes well for achieving our vision of a park that can finance its protection and sustainable development.†Today, truly, was one of the good days. Cheers, Earlier holding statements with additional detail below contact details Marcus Matthews-Sawyer Director: Tourism, Marketing & Communications
  3. Here are the first details from PNK. For those of you who know the park, Tanjung Manta is the cape on the southern tip of Komodo Island near the Manta Alley and German Flag dive sites. This was truly the last stop before open sea. HOLDING STATEMENT: Five Missing Divers Found Alive 11.50am, Saturday 7 June 2008 Five divers were found alive today more than 40 hours after they were reported missing in Komodo National Park. The three British nationals, Charlotte Allin, James Manning and locally-based dive-master Kathleen Mitchinson, and an unidentified Swedish woman and Frenchman, were discovered on the beach on the south of Komodo Island near Tanjung Manta at 11.10 am (Bali time) by Pt. Putri Naga Komodo’s speedboat Cakalang. All divers, who were first reported missing at 5.30pm on Thursday evening (5 June 2008), were reportedly in remarkably good condition after their ordeal and a medical team from Labuan Bajo, the gateway to the park, is heading toward the site to rendezvous with the speedboat The Park is considered one of the world’s premier dive sites but is also home to some of the swiftest and most unpredictable currents and undertows on the planet. Ironically, these fierce currents, a constant concern for divers here, are at least partly responsible for Komodo's famously rich abundance of marine life. Three cheers for the search and rescue team!!! Another update to follow as soon as the divers reach Labuan Bajo. For more information contact: Marcus Matthews-Sawyer Director: Tourism, Marketing & Communications
  4. New: All five divers have apparently been found, alive, on a South Komodo Island beach. This is wonderful news. 12:45 See the new topic for details.
  5. Komodo NP isn't a great location for cell phone signals except when you are very close to Labuanbajo (and even then...). This is also true of some other great locations for diving in Indonesia (Raja Empat, Banda Sea, and Wakatobi National Park), and I think the situation is probably similar (still) in PNG. VHF only works for line-of-sight communications, which can be problematic in areas with lots of islands, such as Komodo and Raja Empat. A waterproof mobile VHF would obviously be useful if you were adrift and could see the search-and-rescue (SAR) vessels, assuming that they also were equipped with a VHF radio, but one cannot assume that all craft participating in SAR operations in locations like this would be equipped with even VHF radios. It would be even more unrealistic to assume that vessels participating in SAR operations in Indonesia or PNG would be equipped to monitor the 406 MHz distress signal from an EPIRB or PLB or to pick up the 121.5 MHz homing beacon. Of course, if you are within sight of a rescue boats or planes, then the rescuers should also be able to see you, provided that you have a large-enough submersible marker buoy or sausage (if it's still daylight), or a good light or emergency flashing strobe at night. The fundamental emergency kit which anyone diving offshore should have, particularly in locations like Indonesia's Komodo National Park, remains the same: a large SMB or sausage (ideally 2 m or bigger.), a good light reserved for emergency use, and a powerful whistle. Adding a flashing emergency strobe, an inflator-hose-powered horn, a small mirror, and a couple of dye packs won't hurt. All this can also be easily carried or incorporated onto any BC. After that, it might be worthwhile also considering adding electronic communication devices such as cell phones or EPIRBS, but one should not rely on these devices being effective in every location. Robert Delfs
  6. I'm forwarding the statement that was released today by Putri Naga Komodo. As of the time of this posting, the divers will have been missing more than 24 hours, so the situation doesn't look good at all. This is a tragic development for everyone concerned. But I also cannot help but think that this was an accident that was almost waiting to happen. R.D. HOLDING STATEMENT: Five Divers Missing in Komodo National Park. Search underway Friday, 10am, 6 June 2008 Five scuba divers were reported missing yesterday afternoon at popular diving spot Tetawa Besar. inside Komodo National Park. An extensive search and rescue (SAR) effort, involving the local police, army, navy, Park Authority and PT. Putri Naga Komodo (PNK), continued today but none of the missing divers have been found as of 10am this morning Bali time (6 June 2008). The five divers were part of a trip organized by local dive company Reefseekers. Reefseeker partner and divemaster Kat Mitchinson is among the missing. The rescue efforts, which are being organized around predictions of the southeast movement of the rapid currents in the Park, is focusing on waters around Tatawa Besar, Tatawa Kecil, Batu Bolong, Karang Makassar, Loh Sebita. It is also believed that if the divers did not make land around Rinca or Padar islands, they would have drifted south past Rinca to open sea. The Park is considered one of the world’s premier dive sites but is also home to some of the swiftest and most unpredictable currents and undertows on the planet. Ironically, these fierce currents, a constant concern for divers here, are at least partly responsible for Komodo's famously rich abundance of marine life. The divers were reported missing to the Park Authority yesterday afternoon at 5.30pm. However, the severe weather conditions of heavy winds and strong waves hampered initial search and rescue efforts and prevented the Floating Ranger Station (FRS) Lajang from reaching the area. A coordination meeting, led by the Head of the local police force, was held at 7pm to form the SAR team and the fleet departed to the location at 22.15 pm along with PNK Speed Boat Cakalang. At 6am this morning, the FRS Lajang and two local dive operator boats (Rajawali and Somba) also reached the location and began searching for the divers. PNK will continue to offer all possible assistance and monitor the situation closely. Out thoughts and prayers go out to the families of the missing divers. Regards, Marcus Matthews-Sawyer Director: Tourism, Marketing & Communications Putri Naga Komodo
  7. John, it looks like the outside maintenance on your house may be getting away from you just a bit! - Frogfish
  8. Airport workers staged srikes at five Indonesian airport Wednesday [7 May, 2008], the Jakarta Post reported today. "The coordinated six-hour strikes hit Sepinggan Airport in Balikpapan, East Kalimantan Frans-Kaisiepo Airport in Biak, Papua Hasanuddin Airport in Makassar (Ujung Pandang), South Sulawesi Sam Ratulangi Airport in Manado, North Sulawesi; and Pattimura Airport in Ambon, Maluku A labor union official was quoted as saying that the union planned more strikes if demands for improvement in airport worker pay, social security insurance and an end to outsourcing were not met, including a possible 12 hour strike on Thursday (today) and a 24 hour strike Friday. Military police reported assisting with airport operations at Hasanuddin Airport in Makassar. The strikes caused delays at some airports, but there have not been any reports of cancelled flights so far. Unfortunately, some of these airports are important hubs for divers travelling from Jakarta or Bali to Manado/Lembeh Strait, the Maluku area, and Derawan in Kalimantan. While Makassar airport is a transit hub on almost every domestic flight route from Bali or Jakarta to any destination in East Indonesia. If we're lucky, the labor dispute will be settled soon and there will be effect on our travel. But if you are planning to transit hrough any of these airports this week or next, it might be prudent to check with our agent or operator for updated news until the disputes are fully resolved. Frogfish
  9. Drew, Thanks for watching my back. I don't mind the ads for viagra and cialis or the interesting letters from my fabulously wealthy new friends in Nigeria who I'm going to try to help get their money out safely. But I hate getting those junk mails from Apple and Adobe. Seriously, I've found Anthony's email address and will send him the file. Robert
  10. Congratulations on what sounds like a super opportunity. Drew's 2nd post on anti-malarials is right on the money. I don't know anyone who lives and works in malarial areas (PNG, Indonesia) who takes antimalarials in prophylactic doses long-term, and it's not just because of the cost. But you do need to have anti-malarials on hand to treat you if you do contract a case. Consider including Larium (Mephaqin) on the list. It has some nasty side-effects and should never be considered for prophylaxis, especially while diving, but it is said to be the most effective treatment against some forms of fulciparum malaria - the kind you need to worry about most. I would suggest you spend a good long time with your doctor working out the contents for your med kit and also procedures you might need to know how to do yourself. If your doctor isn't completely up on tropical medicine, a consult with a specialist might be worth while. Insurance with medical evacuation cover will also be important. DAN will take care of that for diving accidents, but their coverage doesn't include non-diving accidents or illness. A serious manual on first aid and wilderness medicine should go on your list. If you and your partner haven't done a good course first aid and CPR, or haven't done one recently, now might be a good time for doing that. Look into whether you set up an arrangement with your doctor (or someone new) wherebe he/she would be available to consult via email or phone to help with diagnoses and treatment. It will be much easier to set up this arrangement and work out an understanding about how the payments for consultations would be handled now than to try to organize something after you or your parter are sick. If you pm me your email, I'll send you a "work in progress" spreadsheet covering a lot of meds that might be useful for you, including summary information on dosages, ADRs (adverse drug reactions), conflicts with other meds, etc. It might be a place to start when you're talking to your doctor about putting your own med kit together. Edited by Moderator
  11. I had a problem with the way that the Ike synch cord bent sharply out where it came out of the bulkhead fitting on my first housing, long ago. I jury-rigged a fix that kept the cord working - basically this was just the plastic core from a roll of some kind of tape., diameter about two inches. I taped the first few inches of the synch cord around the outside of the core so that the bend in the synch cord was made gently around the core instead of being pulled into a sharp right angle. For what it's worth. Robert Delfs
  12. With respect to exhaust tees, the Apeks XTX200 and XTX100 come with an alternate large exhaust T. I use the big "T" on my primary reg, but keep a small T on the XTX100 spare (on a necklace). In fact, I believe this applies to the entire XTX line, but do check first. These regulators can also be easily converted from right-hand to left-hand hose connections, if you are diving twins and want to run short hoses from both posts. http://www.apeks.co.uk/products/product_ca...?Product=XTX200 The main reason I converted from Scubapro to Apeks a couple years ago was the lack of professional quality regulator servicing for Scubapro in Indonesia. Also the fact that the shop - which shall remain nameless - in Singapore where I preferred to have my regs serviced refused repeated entreaties to allow me to reserve time slots in advance so that I could get my regs serviced during a single visit. But since I switched, I've grown to very much like these simple, well-built, easy-breathing regulators. And the Singapore agent, with advance notice, is usually able to complete maintenance servicing within a few days. Robert
  13. Four cabins are now booked, so this trip is now guaranteed. To accomodate the booking party, the trip dates have been changed to 7-18 December. Frogfish
  14. I'm passing this information on: Due to a sudden charter cancellation for December 9 - 20 in Raja Ampat, Seven Seas is offering a LAST MINUTE discount of 20% on published rates for this cruise. I was just in the same region on this boat last week. December is a great time to do R4. Email: info@thesevenseas.net or check on the SevenSeas website for further details. Frogfish
  15. Back off, CamDiver. I made it absolutely clear in my posting that if they had a boat now, then it was a new one (and it is). I also corrected my post as soon as I heard from a reliable source that the situation had just changed. Frogfish
  16. As I recall, John, you didn't pay us anything at all! All those peeled grapes, the swirling diaphanous fabrics barely concealing tantalizing wonders, the dancing maidens, the intoxicating potions. And us - all the craven newbies eager for nothing more than the opportunity to carry your housing and weights down to the tender, to test the temperature of the waters so that you might easily select the most appropriate items from the racks of test gear from manufacturers desperately hoping for the nod of your approval; all of us humbly waiting in the hope that you might notice those frogfishes and pipefishes which we found in the vain hope of possibly pleasing you, dreaming only of the opportunity to briefly hold in our salt-wrinkled palms a tiny share of your reflected radiance. (Or maybe meet a former Penthouse model.) But none of that meant anything to you, did it John? So can you question now that we felt we had no choice but to rebel against that archaic and meaningless order? That some of us began to lean ever more to the dark side, threw away our McPADI manuals, made bonfires of those stupid WHEELs, ventured into the forbidden land of DECO, wandered ever farther from our decreed buddies underwater, experimented with exotic eastern gas mixes, and even secretly studied the unholy doctrines of DIR? It's a new world now, John. No more kowtowing, no servants, and no more tugging of forelocks just because a big foot dive journalist from the UK heaves into view. To paraphrase the immortal words of B. Traven, slightly censored when they were delivered by the unshaven and irredeemable Alfonso Bedoyo to an unimpressed Humphrey Bogart in Treasure of the Sierra Madre: "Buddies, to god-damned hell with buddies! We have no buddies. In fact, we don't need buddies. I don't have to show you any stinking buddies, you god-damned cabrón and ching' tu madre! Come out from that sh**-hole of yours. I have to speak to you." Yours,
  17. ** Correction ** I've just been informed that Annabel at Aquamarine here in Bali may have purchased a boat last month. If so (and my source is one that is usually "impeccable"), then my post above stands corrected. I'm sure this will be a first class craft, and a welcome addition to the list of safe, well-found day boats operating here in Bali. Frogfish (Robert Delfs
  18. Pakman, the crowds should have thinned out by late September and I'd think it would definitely be OK in October. It's a nice time to be here, and by then, weekends at NP probably won't be a problem either. Yes, it does get cold underneath. Frogfish
  19. Hi all. The sun still sets in the West even south of the equator, Pakman, while Nusa Penida is still east of Bali ((and has been since the Jurassic). You have a choice: you can either watch the sun set from where you stay and commute to Sanur on the bypass highway, or you can stay near where the boats leave in Sanur. Actually, at this time of year (southeastern monsoon), Sanur gets the better breeze anyway. The word on the molas may have got out a bit more successfully than I would like. I'm hearing that there are just too many divers recently, especially on the weekends, and its affecting the molas. I had thought I would finally get some mola hunting in this year just last weekend, but when I heard about the crowds of divers (and fewer and fewer molas), my friend and I decided just to dive Sanur for the hell of it. At least our carbon emission footprint for the day was lower. Actually, we had two ok dives. I can tell you that the water temp was at least 25 and the molas that we didn't see here in Sanur were just as big and friendly as the molas that apparently none of the hundreds of divers in the 20 degree water at Crystal Bay on Nusa Penida didn't see there. So there! (My advice, at least while for the rest of this month while the crowds are heavier, would be to do Nusa Penida on weekdays when there seems to be slightly less crowd pressure than Saturdays and Sundays. Or else arrange to stay in Nusa Lembongan and get to the mola sites before anyone else gets there. And bring your 5 mm suits and hoods.) Like Drew, I dive with BIDP in Bali. By now, I'm sure I've done several hundred dives with Avandy (a good friend) and his people, and I think they're one of the best dive operations I've ever used anywhere in the world. Of course, there are other operators in Bali. as well. Contra Mark, however, and nothing against Aquamarine in particular, but if Annabel now has her own boat, it must be brand new, and I'm surprised she doesn't mention it on her website and that I never see it at the beach here in Sanur. The last I heard, Annabel is still chartering when she has customers who wanted to go to Nusa Penida. I did hear she did a longer term charter last summer during the mola season. The problem with operators who don't own their own boat isn't that they aren't good dive masters or anything, but while they save on overheads, they may not have been able to hire a decent boat when you want to go diving. And Mark, I know Annabel makes a big point of advertising her company as the "only British owned and operated dive shop in Bali", and yes, she definitely is British (though her DMs and instructors aren't), but since you're coming to Indonesia, why would you prefer to dive with a "British owned and managed" dive operation over anyone else's, for example, owned by an ... Indonesian? Although Aquamarine doesn't have their own boat, several other operations besides BIDP do, but there are boats and boats. Some I would be willing to ride in to NP, others I wouldn't (nor would I let any member of my family). The Lombok Strait can be treacherous. If I couldn't go with BIDP (and they are very busy right now), I'd probably go with Bali Hai, despite the fact that it's "Australian owned and managed." (insert smiley here - some of my best friends are Aussies!) Bali Hai is also a bit of a high volume operation for my tastes, but they operate their own boats, know what they're doing, and their people are also experienced and well trained. Lots of places to stay here in Sanur, but I'm told that tourist arrivals in Bali are up 30% this summer (most of them apparently looking for mola molas), so it's not as easy to book a room during high season (now) as it has been the past few post-bomb years. And you can probably forget discounts - some places have reinstituted high season surcharges for this first time in five years. In Sanur, I'd probably try the Parigata, in Batujimbar or maybe LaTaverna (on the beach, run by a friend). Good luck. Message me via the board when you get here - I might be around. Frogfish (Robert Delfs)
  20. I agree, best for us all to calm down, ATJ. I can see where you you might have taken Christian's comments amiss, but I doubt they were intended to offend. The reality is that we all have our hot buttons when it comes to safety. I see red when I run into McPADI divers who seem to think buddy diving was something decreed to Moses on Mount Sinai and that solo divers are somehow kin of Satan and Beelzebub, or who think that a snorkel strapped to the head is an essential piece of equipment but an SMB isn't. And, as you my have gathered, I'm concerned that a lot of divers don't seem to understand how risky certain kinds of profiles can be, and how it's probably impossible to figure out exactly where the dividing line between practical realism and suicidal stupidity really is. Then I have to question myself - have I done any reverse profile dives in the past year, six months, or three months? The answer, I confess, is yes. Have I done dives with shorter than optimum surface intervals? The anwer, again, is yes. About the only things I can say in my defense would be that, (1) I was aware that I was taking additional risk and I took further steps to try to compensate for that, and (2) beyond admitting the fact here, in this message, I haven't publicized the fact that I've done those dives (and they were exceptions to my standard practice, made for very specific reasons), and I certainly haven't publicly advocated reverse profiles or reduced surface intervals in this or any other forum as safe. I know that they aren't, and that if I'd been injured as a result of those divers, it would have been completely my fault, all the way. Other people, on the other hand, get excited by different kinds of divers "sins", and may feel as strongly about my "same ocean same day" buddy diving philosophy as I do about carrying SMBs and diving "bend me" profiles. PGK made a lot of good points. I wouldn't begin to suggest that you shouldn't or can't participate in this discussion, ATJ. But I do feel that divers ( like you or I) should be cautious about discussing practices that depart from well founded principles of safe diving (and you know that I don't mean "McPADI rules) in ways that could lead, or mislead, beginning divers to take on risks that neither they nor we fully understand. OK? Frogfish
  21. This has got a bit out of hand. As far as I'm concerned, the recent twist in this thread wasn't really about your diving skills, atj, whatever those may be. If you will recall, we were talking about solo diving, which led me to recall and post links to the thoughtful articles which Bob Halstead wrote on the subject of buddy diving and the practice of surfacing to relocate a missing buddy some years back. I thought these articles might be of interest here because so many divers seem to assume that buddy diving is the sine qua non of safe diving and that other practices and procedures learned during their 4-day McPADI course (like ascending to locate a missing buddy, wearing a snorkel on mask) are both safe and universally applicable to almost all dives. Some of us question those assumptions. You asked me if I could explain why ascending and then reascending might be a bad idea, and that's what I tried to to in my last post. I also made it clear that I personally didn't think these considerations were particularly critical on a dive to 10 meters, which is apparently what you were concerned about, and reminded you that the original comments about the practice of ascending and redescending were explicitly in reference to dives to "non-trivial depths". I confess that I can't really follow the distinction you seem to be trying to make between a "full dive" and something less than a full dive. Is a full dive "emptying the tank", finishing off a memory card, or what? In any case, I don't think I've ever seen any reference to a distinction between "full dives" and "half" or "quarter" dives in anything I've ever read in modern dive decompression theory or practice A bounce dive to 30 meters is still a 30 meter dive in any model that I know of. And nobody assumes that your dive to 30 meters is a square profile with the entire bottom time spent at max depth. If you can provide a reference to the legitimate authority which you are basing your argument (if that's what it is) that multiple bounce (or sawtooth) dives to depths of 30 meters or more do pose additional risks of DCS compared to an orthodox profile, then I and many others would be very interested to see it. If you don't know of any reputable authority, then I would urge you to be very cautious about inventing your own decompression theory and/or rules for handling profiles and ascents, and to be doubly cautious about sharing your speculations with others who may not have the experience and knowledge to distinguish practical realism from dangerous nonsense. I just noted that your sig references a link to your logged dives since certification in 1978, totalling roughly 300 dives over the past 30 years, and roughly 100 dives over the past three years. The vast majority of your dives appear to be limited to depths of 11-15 meters, and there are only a handful of dives to 30 meters, none deeper. Nothing wrong with any of that, and it's nice to see that you've been diving for a long time, and not to be harsh, but I don't think 300 lifetime dives, mostly to less than18 meters, is the kind of experience that would make you an authority on what makes certain dive profiles safe or unsafe, do you? I hope it's clear by now that this discussion wasn't really about you or your dive skills, and also that I really don't care what you and your buddy do or don't do, at any depth. Bounce up and down all day if you want. But if you really believe sawtooth dive profiles are not really dangerous under certain conditions that you believe you somehow have the knowledge and experience to figure out on your own, then I'm not sure I'd want to talk about it in a forum like this one, and definitely pas devant les enfants, ok?
  22. Wow, with John B. and Eric, that's two people here whose photos have broken into the painful end of the "skin trade." I understand getting a tattoo hurts a lot, so I'm assuming the Screamin' Turtle would have hurt a lot. I would find it hard to charge royalties to someone who had gone through that in order to wear one of my images on their body - for the rest of their life? Frogfish
  23. ATJ, I'm happy to do so. Halstead's Undercurrents piece does focus on the problem of people surfacing alone, and not at the place and time that the chase/tender boat driver might expect, which is serious enough. The problem with ascending and redescending is that your nice safe dive profile has just turned into a nasty double spike. Your computer probably won't take that into consideration. Suunto and Mares computers with partial RGBM implementations should try to compensate by cutting your bottom time for the remainder of your dive, at least in theory. The purpose of RGBM, however, is not to make it possible to dive suicidal profiles, and no reduction in bottom time on the second half of the dive could ever make ascending and redescending safe. Let's say you and I did a dive together to 30 meters, then ten minutes after we surfaced, I said, screw the surface interval, let's do another dive to the same depth right now. Would you agree to go with me? If not, then why would you ever consider doing a second dive after a surface interval of only one minute? The problem with a quick re-descent is that it can recompress those zillions of nitrogen bubbles streaming out of your tissues into your bloodstream after your ascent to look for your missing buddy (and you probably didn't do a 3 minute safety stop either, did you?) so that they become small enough to pass through the lung barrier to the arterial side, where they can then re-expand after your second ascent. That can be where a serious problem starts, and that's why cutting bottom time after the re-descent won't protect you. This is why we do surface intervals between dives, and why sawtooth dives (even with only two "teeth") can kill you. There is apparently some new data showing that divers (often a divemaster) are particularly vulnerable to DCS after doing a quick dive or free-dive down to free the anchor following a normal dive, even though this is usually redescending to only 12 meters or so, and only for one or two minutes - hardly any "bottom time" on the "2nd descent" at all, really. I assume that ascending and redescending to and from depths of ten meters or less would be much less likely to cause DCS problems - I think I did qualify the comment in my original post to apply to "non-trivial depths." But I have seen people ascend to look for a missing buddy from depths in the 30 meter range, then re-descend to the same depth ... and not always with their buddy either. (So what was the point of that?). BTW, I think you were a little harsh in your response to ChristianG. Is somebody up past their normal bedtime? Frogfish (Robert Delfs)
  24. This would be nice. It's too bad the quality of the scans on GoogleEarth is so uneven, or it might be useful to pull together data on dive sites linked to GoogleEarth coordinates. (Most of you probably know that GoogleEarth coords don't necessarily line up precisely with any paraticular navigation chart, nor with the datums used by gps systems, in some parts of the world. Some of the most interesting places to dive here in Indonesia - Raja Empat, Triton Bay, Banda Sea - have only poor quality low detail scans on GE. Komodo is pretty good, and parts of Bali are OK. (If you want to see where I was diving today, "fly" to Sanur, Bali, Indonesia and check out the slope on the outside of the barrier/fringing reef outside the lagoon at 8°41'47.54"S, 115°16'27.12"E. Saw a nice Ceratosoma gracillinum nudibranch,only the second one I've ever seen - the first one was at exactly the same place, same dive, possibly same rock and same slug - six months ago.) Frogfish (Robert Delfs)
  25. At least NWDiver isn't saying that after the separated divers relocate each other at the surface (assuming they actually do) that they should subsequently re-descend and resume the dive, a procedure still taught by some training agencies - including, if I'm not mistaken, McPADI ("Over Five Million Sold)". Bob Halstead is just one of the knowledgeable, experienced divers who has condemned this practice as unsafe (in an Undercurrents article some years ago). Except in situations where the depths involved are trivial, I find it hard to believe that anyone here would adhere to the practice of surfacing to relocate a lost buddy and then re-descending. Not a good idea. Halstead may also be the foremost exponent of the argument that diving with a buddy actually increases the potential risks of diving. His diatribe (in a now famous "Aquacorps" article) "On your own: the buddy system refuted" is well worth reading, and has been extensively discussed on other online and other forums over the years. I think Halstead makes the case against the buddy system - or at least the simplistic buddy diving practices taught by some training agencies - far better than I ever could. For what it's worth, if I'm diving with a beginner or inexperienced diver who requires constant monitoring, then I simply don't bring my camera with me. In that situation, we're not diving as buddies - I'm diving in the capacity of an (unpaid) instructor or dive guide. If I run into a problem on the dive myself, I know I will have to deal with the problem on my own while remaining responsible for the safety of the diver I'm accompanying. And I certainly won't be expecting help from the person I'm with. If you are a "dependent" diver (McPADI's other motto: "Are you co-dependant? We will certify you!") and you don't have a friend willing to take care of you underwater for free (thus ensuring that service you receive will be worth at least what you are paying for it), then you should bite the bullet and hire a real, qualified instructor. No shame in that - I will always hire an instructor (or rely on a much more experienced colleague/friend) to help me on any dive that I have reason to believe may be beyond my experience or capability. What's really insane - and may be the McPADI's ("The way the world learns to dive") most important contribution to unnecessary and avoidable dive fatalities - is the practice of pairing off divers according to experience and skills and forcing them to dive together as buddies, thus ensuring that the two least experienced divers in the water - the two persons who are simultaneously the most likely to require assistance during the dive and also the two who are least qualified to give it, will dive together. Great system. Frogfish (Our buddy motto: "Same ocean, same day")
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