Mae, an interesting question. In Alvin we have to take our own atmosphere with us. There is no tether or surface supplied air for us to breath. Here's how we do it...

In Alvin we want to reproduce the normal atmosphere we breath on the surface. After the hatch is shut the occupants start to consume the available oxygen and increase the amount of CO2 inside the personnel sphere. In the rear of the sphere we have three pressure bottles of pure oxygen and all day during the dive we slowly add oxygen to the sphere, about 1.5 liters of gas per minute. CO2 in high concentrations is poisonous so it's important to remove this from the sphere's atmosphere. We do this with a device called the scrubber. It uses simple chemicals to convert CO2 into water and calcium carbonate, essentially chalk, which, just so happens to absorb the small quantities of water produced. Pretty neat chemistry, huh?

As far as helium goes, scuba divers sometimes use a “mixed gas” when they need to go deeper for extended periods. Often this mixture is pure helium and pure oxygen. The diver would mix the percentages of each gas according to the particular needs of the dive. The helium, not used by the body, replaces nitrogen which can cause abnormal conditions in the body when absorbed by tissues in high quantities. Look up "nitrogen narcosis" and "decompression sickness" also known as the "bends". And yes, breathing too much helium, without any oxygen, could not only cause you to be ill, it could be deadly.

A long answer, but the physiology of diving is quite interesting. As far as diving in Alvin is concerned, our atmosphere requirements are quite simple. As long as we have enough oxygen to keep our atmosphere in the range between 17.5% to 21%, and our scrubber is working, we're ok.

It's been really great to have you all following along with us, Leona. It really means a lot to all of us. Thanks for being a part of the expedition.

Hi folks,
When we left San Diego around October 20th and started the trip south toward our dive site here at 9°50'N we started to watch the weather. Within a few days the ship's Captain, Gary Chiljean, let everyone know that there was a tropical depression off the coast of Mexico and that it might form into a tropical storm or even a hurricane. The ship gets weather data via satellite and by using this data the Captain changed the course of the Atlantis westward to avoid the path of the storm. The most we ever saw was a day or two of following seas, swells that travel faster than the ship and pass us from the stern. It really was pleasant sailing. It turned out that the hurricane became a Category 4 storm, quite strong. We never really saw any of that nasty weather. Ironically the hurricane actually passed along the path originally planned for our trip.

Hi, Talon — The tubeworms are in the Animal Kingdom. Thanks for your question.

Hey, Joey — Those are good questions. I'd have to say that there’s always something odd or strange to see on every dive. One of the best places on our Extreme 2002 dives is "Tubeworm Pillar." It’s an awesome place, and there’s always something interesting to see there. Alvin has a tremendous safety record. Since Alvin’s first dive, there have been only a few instances when the sub experienced problems that were potentially dangerous. One example was in the 1990s. The sub had unknowingly been scooping mud up into its lower equipment areas. A lower fairing had come loose and allowed a large quantity of mud to add mass to the submersible. When the pilot tried to ascend, the sub didn’t respond. As in all problems, the pilot contacted the surface for advice and in a small matter of time, the sub was on its way home although at a much slower rate than normal.

Hey, Ricardo — When we dive in Alvin, we have to take our own atmosphere with us. After the hatch on the sub is shut, we start to consume the available oxygen in the sub and increase the amount of carbon dioxide (CO2) inside the personnel sphere. In the rear of the sphere, we have three pressure bottles of pure oxygen, and all day during the dive we slowly add oxygen to the sphere, about 1.5 liters of gas per minute. CO2 in high concentrations is poisonous so it's important to remove this from the sphere's atmosphere. We do this with a device called the scrubber. It uses simple chemicals to convert CO2 into water and calcium carbonate, essentially chalk, which, just so happens to absorb the small quantities of water produced. Pretty neat chemistry, huh?

Hi, DeRidder High —

Thanks for following along with us, and sorry it's taken so long to reply. We heard some schools in your state had experienced tornadoes. I hope everyone out there made it through okay.

When we left San Diego around October 20th and started the trip south toward our dive site here at 9°50'N, we started to watch the weather. Within a few days the ship's Captain, Gary Chiljean, let everyone know that there was a tropical depression off the coast of Mexico and that it might form into a tropical storm or even a hurricane. The ship gets weather data via satellite and by using this data the Captain changed the course of the Atlantis westward to avoid the path of the storm. The most we ever saw was a day or two of following seas, swells that travel faster than the ship and pass us from the stern. It really was pleasant sailing. It turned out that the hurricane became a Category 4 storm, quite strong. We never really saw any of that nasty weather. Ironically, the hurricane actually passed along the path originally planned for our trip.

In regard to your questions about Alvin, the sub basically sinks to the seafloor. Once just above the seafloor, the pilot maneuvers the sub using a joystick. Maneuvering the sub can be difficult, especially in tight areas with strong currents. Off the coast of Oregon, along the Juan De Fuca ridge system, is an area of immense vents that are tightly packed together, have very hot water (over 350° Celsius), and routinely have very strong currents. On some dives, the currents are strong enough to make the vent plumes run horizontal from the vent orifice. This is a good indication of a difficult set-up for sampling. It can be very frustrating trying to keep the sub ‘parked’ at a vent site while fighting a strong current. Also, we can’t see much to our port or starboard sides and nothing at all behind us. Over time, the pilots become very spatially aware, noting nearby structures and their relative positions to the vehicle, flying by ‘gut feeling’ to keep us clear of obstacles.

The only real differences between the surface and the seafloor are wave interaction and the sub’s buoyancy. On the surface, we have to deal with the ocean’s waves and swell pushing Alvin around. Under the surface, there is no wave effect. Alvin is designed for the extreme and operates best down near the seafloor. Thanks a lot for the questions and for following along.

Hello, Caroline — The research these scientists out here are conducting is aimed not only at answering some mysteries about the planet we live on, but also possibly producing a number of other important benefits for me and you, like developing new medicines for treating cancer and other diseases, creating new products that can withstand high temperatures, and more.... People often ask, “What sort of training does it take to be a pilot?” Normally the answer includes reference to two years of on-the-job training and an engineering degree: standard responses to a routine
question. But the real answer is it takes time, and experience, and many humbling hours inside the sphere. As pilots, we’re the front-line guys, performing most of the actual sampling and manipulation. Scientists expect a lot from us and we’re dedicated to giving our best. Often the dives are very successful, and we return to the surface from a productive day below. But it’s the days of repeated frustrations and failures that help shape a pilot. I spend my quiet time in the evening after a marginal dive reflecting on the circumstances that helped create the problems below. Reliving the time in the sphere helps me identify better methods for meeting the many challenges we face when pursuing good science in such an extreme environment. And as always, I look forward to getting right back in the sub
and doing it all over again, with a better perspective and more positive results. Thanks for your questions.

Hi, B. S. Hill — There is a link to the UNOLS site from this Extreme 2002 Web page: http://www.ocean.udel.edu/extreme2002/Mission/rvatlantis/index.html. It should help answer your questions about this important organization. Thanks for your question.

Hi there, Curious — We use a variety of tools, but Alvin's manipulator arms are critical to most of our collections. Thank for your question.

Hi, Matt — It generally takes us about an hour and a half to descend 2,500 meters. Thanks for diving with us.

Hi, Mrs. Grasso's Class — Boy, you sure have some good questions. Since Alvin’s first dive, there have been only a few instances when the sub experienced problems that were potentially dangerous. One example was in the 1990s. The sub had unknowingly been scooping mud up into its lower equipment areas. A lower fairing had come loose and allowed a large quantity of mud to add mass to the submersible. When the pilot tried to ascend, the sub didn’t respond. As in all problems, the pilot contacted the surface for advice and in a small matter of time, the sub was on its way home although at a much slower rate than normal.

Many different pieces of equipment can malfunction on a dive and have minimal impact on dive success or on safety. When a problem is encountered, the pilot and surface watch evaluate its impact on the dive and determine the proper action to take. Every dive is governed by our Operations Manual, the group’s ‘bible’ and specifically a list of ‘Minimum Requirements for Diving.’ Our morning pre-dive checks ensure that the sub meets the minimum requirements and identifies any other minor problems.

During a dive, systems are monitored constantly with the critical components — atmosphere, electrical distribution status, communications — monitored at least every half hour. Certain problems, loss of comms for example, will immediately end a dive. More serious problems and our reactions to them are outlined in the OPs manual. The sub has a wide range of redundant and emergency systems to help ensure that we return to the surface. In the long run, it’s the coordination of the group, the good operational decisions of the pilot, and our specific operational guidelines that have maintained our perfect safety record.

I think that getting a job with the Alvin Group is a combination of education, experience, and timing. You’ll need an engineering degree, mine's in Ocean Engineering, and some time working in a technical field. Some of us are ex-Navy guys. I spent six years in the service managing, operating, and repairing missile fire control weapons systems. Other guys have worked as engineers in industry prior to moving to the group. Many of us are accomplished scuba divers and love other water sports like surfing. About half the group, Pat Hickey and myself for example, are pilots in the air as well. The group is always looking for people with solid technical skills to join the group. Oh yeah, you have to like going out to sea ... we do an average of eight months a year out here. I love being an Alvin pilot. I love machines, especially ones that fly, float, dive, or drive. If I couldn't do this for a job, I'd like to be an astronaut or an airplane pilot. Thanks for all of your questions.

Hi, there's always something interesting to see at the vents, from zoarcid fish to Pompeii worms, tubeworms, vent crabs, mats of bacteria, and more. It's really difficult to rank one organism as more amazing than another. Thanks for writing.

Hi, we really haven't had problems with seasickness in the sub. Some people may feel a little queasy when we're on the surface waiting to be retrieved because of the bobbing in the waves. It is possible to go to the bathroom in the sub using what is called a "human range extender," which basically is a bottle for urine. Most people are careful not to drink a lot of fluids before getting in the sub for an eight-hour dive. Thanks for the questions.

Hello Amelia and Chris — During this expedition, we've been working at a depth of about 2,500 meters. The deepest recorded dive by a SCUBA diver is 282 meters. The pressure at 2,500 meters is more than 250 times the pressure you feel on land. If we were not in Alvin's protective titanium sphere, there is no way we could survive. Thanks for your questions and for diving in with us.

Dear Mystery Writer — Most of the organisms cannot survive the change in pressure. However, young (larval) vent crabs can survive the trip to the surface. Thanks for your questions.

Hi, Brianna and Bekah at Avon Grove High School — We had a couple of "green" scientists out here when we first got under way and when we experienced some rough seas as we adjusted our course to avoid Hurricane Kenna. Sometimes it's hard for people to re-adjust to the movement of the ship when we are under way again and steaming back into port after being out at sea for several weeks. Some people take medication like Dramamine to help avoid seasickness. Thanks for your question and for following along with us.

You know, James, diving in Alvin is one of the most challenging and rewarding experiences imaginable. I've yet to have a dive where I haven't learned something, either about the submersible, about the science, or about myself. Thanks for your question.

It's certainly fascinating, but not scary. Maybe I could say that during one of my early training dives, when I dropped the temperature probe off of the science basket, that the reaction of the lead pilot during the dive was pretty scary! The sub’s titanium sphere keeps us at about one atmosphere, so we never experience a pressure change .... thus, no ear "popping." Thanks for the questions.

I never feel scared, Liza Anne, but every pilot realizes he has a major responsibility, which each of us has been well trained to handle. The biggest responsibility that the Alvin Group has, pilots and techs, is to ensure the safety of our observers. Alvin’s record over the last 38 years is perfect. No one has ever been hurt. Everything else is secondary; safety of the vehicle and mission accomplishments are always secondary to getting the folks back ‘home’ in good shape, although they’re often tired and a bit stiff. Thanks for your question.

Hi, Mystery Writer.... We don’t experience any true pressure change. Alvin’s titanium hull keeps us at about one atmosphere, protecting us from an external seawater temperature and pressure that would kill us instantly. At our maximum depth, the force on our viewports alone is over seven hundred thousand pounds. That’s like having a jumbo jet balanced on the 12"-diameter viewport. We do get stiff necks and backaches from the cramped position we're in during the dives.

Hello, Mystery Writer — ‘Hard’ is a relative term. I’d use the word challenging. Different situations during the dive, like positioning to sample, finding a specific site, or maneuvering in strong current near the vents can be difficult. It’s important to know the limitations of the vehicle and your own abilities and balance those during the more difficult times below. You can learn all about Alvin on the Woods Hole Oceanographic Institution's Web site. Thanks for your questions, and good luck with your project.

Hello to another Mystery Writer. Thanks for your good wishes. The answer is "b" — battery-powered. The primary direct consumers of the 120V power are the propulsion system and external lights. The 26V power, derived from the 120V batteries, supplies all services within the sphere, including the control systems, instruments, and computers.Thanks for the question.

Hi, Sebastian — We don't really see any indication that the light from Alvin harms the fish. Thanks for your question.

Hi, Thomas — That's a good question. Maneuvering Alvin can be difficult, especially in tight areas with strong currents. Off the coast of Oregon, along the Juan De Fuca ridge system, is an area of immense vents that are tightly packed together, have very hot water (over 350° Celsius), and routinely have very strong currents. On some dives, the currents are strong enough to make the vent plumes run horizontal from the vent orifice. This is a good indication of a difficult set-up for sampling. It can be very frustrating trying to keep the sub ‘parked’ at a vent site while fighting a strong current. Also, we can’t see much to our port or starboard sides and nothing at all behind us. Over time, the pilots become very spatially aware, noting nearby structures and their relative positions to the vehicle, flying by ‘gut feeling’ to keep us clear of obstacles.

On the surface, we have to deal with the ocean’s waves and swell pushing Alvin around. Under the surface, there is no wave effect. At depth, the sub begins to cool off and as the dive progresses, the sub becomes less buoyant requiring periodic adjustments to our variable ballast system to maintain neutral buoyancy.

On a routine dive we don’t experience any technical difficulties due to the environment. Alvin is designed for the extreme and operates best down near the seafloor. Thanks for your question.

Hello, Emily — I really haven't been scared by any creature although I know Dr. Cary mentioned during the "Phone Call to the Deep" on Nov. 8 that he once looked out of his view port and saw a human head fish, or "Yul Brynner fish." Be sure to listen to the phone call to find out more. Thanks for your question.

Hi, Jamie! — I ended up working for the Alvin group after finishing a degree in Ocean Engineering at Florida Atlantic University. I had also spent six years in the Navy where I learned to love the oceans. I’ve also worked as a dive master and as a diver on small boats in Florida. Diving showed me how amazing life in the oceans can be. One night while searching the Internet for job openings, I found the posting for a position in the group. It sounded so interesting that I sent off my resume the next day and within six months I was hired. I’ve been here over six years now, and it’s been very rewarding.

Hi, Charlie — Thanks for your question. I've always had a great interest in science and technology, but I never really planned to be a member of the Alvin group. I guess I owe most of my interests in science and technology to my family. As I grew up, I had a questioning mind and would read magazines and watch programs that discussed all types of science and new technologies. I ended up working for the Alvin group after finishing a degree in Ocean Engineering at Florida Atlantic University. I had also spent six years in the Navy where I learned to love the oceans. I’ve also worked as a dive master and a a diver on small boats in Florida. Diving showed me how amazing life in the oceans can be. One night while searching the Internet for job openings, I found the posting for a position in the group. It sounded so interesting that I sent off my resume the next day, and within six months I was hired. I’ve been here over six years now, and I love my job.

Hi, Brian at CCDS — Yes, each observer viewport has one or more lamps positioned to illuminate viewing areas. The observer viewport lights are individually controlled by switches near the viewports and by the pilot’s master control switches. Thanks for your question and for following along with us.

Hello, Nicholas — The pilot's job is to make sure that everyone has a safe trip in the sub. The experience as a whole is very gratifying, and I guess the opportunity to participate in all of the science, especially on the front lines, to see a world that few will ever see firsthand, is the most exciting part. Also, I love machines, especially ones that fly, float, dive, or drive. I ended up working for the Alvin group after finishing a degree in Ocean Engineering at Florida Atlantic University. I had also spent six years in the Navy where I learned to love the oceans. I’ve also worked as a dive master and a a diver on small boats in Florida. Diving showed me how amazing life in the oceans can be. One night while searching the Internet for job openings, I found the posting for a position in the group. It sounded so interesting that I sent off my resume the next day, and within six months I was hired. I love my work.

Hi, we attach a total of 832 pounds of steel descent/ascent weights to the sub every morning we dive. Otherwise, Alvin would remain on the surface. On descent, at about 50 meters from the bottom, the pilot releases two of the four weights, adjusts the sub’s buoyancy with water (added to or removed from tanks in the sub) to make it weightless (not mass-less). When it’s time to surface, the last two weights are released and the sub ‘floats’ to the surface. Thanks for your questions.

That's a good question, Andrew. We actually use a combination of both weights and ballast tanks. Without the 832 pounds of steel descent/ascent weights we attach to the sub every morning, Alvin would remain on the surface. On descent, at about 50 meters from the bottom, the pilot releases two of the four weights, adjusts the sub’s buoyancy with water (added to or removed from tanks in the sub) to make it weightless (not mass-less). When it’s time to surface, the last two weights are released and the sub ‘floats’ to the surface. The weights are not harmful to the seafloor. They do make it possible for us to reach the seafloor and study it. Thanks for your question.

Hi, Mike — Boy, those are some questions! First off, no one has died aboard Alvin. In what is now our 38th year of operation, the sub has a perfect safety record, and we work hard to put the safety of the observers first during every one of our dives.

Is it boring on the ocean floor? Never!

Well, hello there, Anonymous at MCMS — I love machines, especially ones that fly, float, dive, or drive. Alvin is the best toy a guy could ever ‘play’ with.

Hi there, Rachael — What do I do for fun? Life on ship affords time to read, and we have a good library. We have no television (yeah!) but can select movies from our large selection of DVDs. We have some decent work-out equipment as well. I play guitar and spend my time reading and studying new things. Oh yeah, all of us also dream about being on shore again, relaxing with our friends and doing
other fun things like surfing, diving, or skiing. Thanks for your question.

Hello, Sierra! — I think that getting a job with the Alvin Group is a combination of education, experience, and timing. You’ll need an engineering degree — mine's in Ocean Engineering, and some time working in a technical field. Some of us are ex-Navy guys. I spent six years in the service managing, operating, and repairing missile fire control weapons systems. Other guys have worked as engineers in industry prior to moving to the group. Many of us are accomplished scuba divers and love other water sports like surfing. About half the group, Expedition Leader Pat Hickey and myself, for example, are pilots in the air as well. The group is always looking for people with solid technical skills to join the group. Oh yeah, you have to like going out to sea ... we do an average of eight months a year out here.

Hi, Ann from Springer Middle School — Forward illumination is provided by 400-watt metal halide lamps. Thanks for your questions and the good luck!

Sorry it took me a while to respond. Julie is doing just fine. She was a little irritated that Tony Tarantino was using her cup from last year (see her journal from Oct. 24) but I think she's over that now. Just kidding! She's been working hard and should soon be on her way home.

The biggest responsibility that the Alvin Group has, pilots and techs, is to ensure the safety of our observers. Alvin’s record over the last 38 years is perfect. No one has ever been hurt. While important, mission accomplishments are always secondary to getting the folks back ‘home’ in good shape.

We do our best to help the science team accomplish their mission, and we are often the first to see some of the vent phenomena, which is very rewarding. We help to collect samples, take temperature readings, and record the environment with cameras inside and outside on the sub. It takes plenty of teamwork and communication to help fulfill our scientific objectives.

Dave Olds, a group member up until about two years ago, once said, “This is the best and worst job...” What he was trying to say was the experiences as a sub pilot out here are amazing, but we all give up a lot to get here. Eight months a year we’re out here working, often up to four or five weeks without a day off. Prior to this job I had a home, a girlfriend, and all the other things ‘normal’ people enjoy. Since 1996 when I started with the group, I have maintained no permanent residence, traveling around the U.S. and world during my vacation time. It’s a nomadic lifestyle that I’ve chosen, at least for the time I stay with the group. I realized that this was a chance of a lifetime and decided the sacrifices were worth it in the long term. Someday soon I’ll return to the ‘real’ world, probably ending up boring people with tales of my time in the group. Thanks for your question.