Calvin19

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Posts posted by Calvin19


  1. bjgraybeal

    ***I actually was setting down writing a very coherent response to his first post. It was all about pressure suits vs pressure breathing and an old U2 pilot that I used to know. I got interrupted yesterday and didn't get to finish it. By the time I checked on it again last night it was in full swing and I just went and got some popcorn.

    Things I will say for his plan. 60,000 ft is at least way more doable then the exponentially larger problem of trying to set a new record at 130,000+ A 60,000 foot balloon is at least doable for decent size loads. There are certainly places where they launch balloons like that commercially for weather and other things. In fact they do it at all latitudes. On one of my trips to Canada I was talking to a guy about a launch site... I don't recall if it was actually on Baffin or a near by island. Site wasn't even a town. It was just an out post where they went to launch balloons using hydrogen. Way too dangerous to be near any town. So commercial stuff is out there but it's generally in the middle of no where with flight paths away from every thing, like over oceans. Obviously you can get permits to launch from any where you like. Look at the balloon racers for the around the world. But I can't even conceive of trying to reuse or recover an envelope from some thing like that. Never even heard of it being done. Every thing I've ever seen they just cut away the payload and recovered it.

    About air craft. I think it would be very... interesting to try to jump out of an air craft at that altitude. Look up "Coffin Corner" in the history of high flying aircraft. Basically you can get into this situation where as you fly higher your stall speed of course goes up and you get into a corner of the graph where lines for critical mach number and stall speed start to converge. It's a scary place to fly but a lot of high flying aircraft have wound up there, the U2 as a prime example. What's relevant here is that the air plane just can't slow down. No Cut! So we're talking about a jumping out of a jet aircraft with no cut. Density is low but the indicated air speed is still pretty high. I think we're talking ejection seat, and ejection seats are no fun. Normally it's a question of how badly you're injured. Any body know what the highest jump made from an air plane is? What kind of plane could you jump from at 60,000+ feet where you wouldn't lose the aircraft? I think there are ways you could build one. There was once a design, old supersonic fighter bomber idea, where they were looking at deploying ordinance out the tail of the aircraft between the engines rather then through a bomb bay or under wing. They wanted to drop a bomb or fire a missile supper sonic and were worried about the bomb taking out the plane. I just can't think of a lot of planes that could fly at that altitude with a door open.

    If you want to do this I'll tell you how to do it. It won't be cheep but the next record will be set with a rocket. There are people talking about this right now. If you want to set a new record, I'm talking 200,000 feet, give us a call: Exos Aerospace

    http://exosaero.com/

    But don't even waist our time till you have secured... lets say $3,000,000, that's just a guess off the top of my head, to build you a custom air frame. It's not exactly what you're looking for, some thing cheep enough to be a new business that the ordinary skydiver is going to want to jump. But once built, normal operating cost are about $250,000 per flight. Let's talk wet lease.

    Lee



    Very nicely said. There are a few balloon companies now, launching from quite a few places around the world. Currently working for a stratospheric balloon company under one of the world's top balloon designer, I proposed this question. How would you set up a ballooning operation to lift ~10 jumpers to 50,000-60,000ft and make it equal to the price skydivers are paying for a nice complete rig? He provided his answer and I became curious if there was already talk in the community about doing this. As far as reusable balloons, they are not often used but I have used them. Some painter's plastics are actually thinner than what is used in balloons.

    For a true space jump (61mi+) a rocket must be used. The ride itself would not be expensive, ~$100,000. There is already a company with the resources. The test jumps, equipment, engineering, training, etc is the real cost. $3,000,000 for a package of equipment, engineering, testing, and a ride is very reasonable.


    I agree with everything here.^ (quote and response).

    My main points were the ideas of re-using envelopes, 'hovering' a buoyant unpowered aircraft, and other logistics of using a balloon.

    An airplane with a large window between mach and stall would be doable at 40000', and far more practical. coffin corner was the reason for the edit in my post a few responses back from 60k to 40-50k.

    And of course never said impossible, only very expensive and difficult. If you get the company together I would gladly help crew.

  2. bjgraybeal



    First, the reuse is a means to lower the price, but balloons are cheap. Plastic is a few hundred dollars and only a few hundred in labor, so one time use can also be done.


    I'm curious about that. Cheap is very relative. I looked into building several 130'k, 300kg payload zero pressure envelopes. large hangar/factory/warehouse, materials, parts and custom tools to just get started would be well past five digits. Assuming learning curve, R/D, testing, permits, airspace, certifications, is not included. After quotes we got from manufacturers in 2011, building our own envelopes was more attractive. Moot now of course. space jumping is so 2012.



    Quote


    As far as commercial flight use, you might want to let worldview enterprises know that this is not possible. They plan on taking tourist up to 100,000ft and descending under a massive square parachute in about a year.



    I didn't say not possible, just really expensive.
    And their initial business plan is WAY more practical than 20kUSD a head for jumping.

    Seriously, just use a plane. Or even a hot air balloon with fewer jumpers and 40,000'

  3. bjgraybeal

    ************
    Rough estimate. If divided between 10 people, renting suits, and an established business, I would guess $10,000-$20,000. and a company who would do this could reuse the balloon and helium and rent the suits. This would keep their overhead low and possibly lower customer cost.



    A gas balloon envelope that can take "~2000lb" (OP's number) to 60k MSL would be really really big. If you find a manufacturer that will make a re-usable gas balloon to those specs I will give them a gold star. A big high five to whoever pays for it. Who I don't want to meet is the poor ground crew gathering up a few million square feet and thousands of pounds of fragile, expensive balloon.

    Well then I deserve a gold star. It is called a super pressure balloon. If it is to be reused then it is never fully deflated, but brought down and stored in a hanger. The balloon would not be as big as you think, somewhere in the neighborhood of 200,000 cubic feet volume. Weight would be around 100-150lb at the most. Sorry, you have met a poor ground crew member who has cleaned up the plastic.

    At least we are on the same team as far as GC goes. :P (12 years GC experience and free PG drops whenever there was room). I also did consulting work for Google's Project Loon (super-pressure helium long duration communication flights)

    I find it exceptionally hard to believe that a 200,000cf envelope that can do anything but a one time, one-way trip would weigh 150lb.

    A super pressure balloon is normally not intended for multiple inflations or flights. Re-usable gas balloons, even those that are meant to stay more or less inflated and hangared are at best comparable in mass per envelope area to hot air balloons.

    It is not easy reusing a balloon but it is possible. I have personal experience unpacking, inflating, and launching a balloon with a 2,200lb payload and designed to float at 110,000ft. the weight of that balloon was only 60lb. granted a reusable super pressure balloon would need more robust film, but it wouldn't add a ton of weight. It could be more feasible to have a one time use balloon that weighs only 30-40lb.

    Reusing a condom is also doable. But let's not grab the lube just yet.
    The point of this theoretical venture is to get RAF felix wannabes to 40k or 60k MSL, somewhat reliably. ignoring this would be classified by any insurance company, aviation authority, or investor to be a commercial flight. Ignoring that even hot air balloons are comically un-dependable as reliable aircraft compared to fixed wing.
    I doubt a 'used' zero-pressure or super-pressure balloon made out of film that makes painter's plastic drop-cloth seem like bullet-proof kevlar would make anyone very confident.


    IMO you would be better off modifying an existing aircraft already capable of 60kMSL (edit:40-50k, 60k gets a lot more expensive) flight for jumping.

  4. bjgraybeal

    ******
    Rough estimate. If divided between 10 people, renting suits, and an established business, I would guess $10,000-$20,000. and a company who would do this could reuse the balloon and helium and rent the suits. This would keep their overhead low and possibly lower customer cost.



    A gas balloon envelope that can take "~2000lb" (OP's number) to 60k MSL would be really really big. If you find a manufacturer that will make a re-usable gas balloon to those specs I will give them a gold star. A big high five to whoever pays for it. Who I don't want to meet is the poor ground crew gathering up a few million square feet and thousands of pounds of fragile, expensive balloon.

    Well then I deserve a gold star. It is called a super pressure balloon. If it is to be reused then it is never fully deflated, but brought down and stored in a hanger. The balloon would not be as big as you think, somewhere in the neighborhood of 200,000 cubic feet volume. Weight would be around 100-150lb at the most. Sorry, you have met a poor ground crew member who has cleaned up the plastic.

    At least we are on the same team as far as GC goes. :P (12 years GC experience and free PG drops whenever there was room). I also did consulting work for Google's Project Loon (super-pressure helium long duration communication flights)

    I find it exceptionally hard to believe that a 200,000cf envelope that can do anything but a one time, one-way trip would weigh 150lb.

    A super pressure balloon is normally not intended for multiple inflations or flights. Re-usable gas balloons, even those that are meant to stay more or less inflated and hangared are at best comparable in mass per envelope area to hot air balloons.

  5. chutem

    *********Yes, balloons can hover over the earth by using the different directions of wind and different altitudes.



    Can this be done at the same time as climbing to 40k' in a "reasonable" time?

    Very few planes can you take to 40,000ft and jump. But the answer to your question is anywhere from 1,000ft/min and up. It really depends on how much helium is wasted in the free lift. If 20,000lb extra were thrown into a balloon lifting only 2,000lb, it would take off like a rocket ship.

    Not asking how fast a balloon can climb, asking if you can "hover" a balloon over a certain area while at the same time climbing to 40k' in a reasonable amount of time?


    Longer answer:
    Assuming perfect conditions in the most ideal area in the world, maybe. If you use a tether. A 60,000' tether for something with ~4000lb inertial mass would weigh (assuming lightest material available) about 4000 pounds.

  6. chutem

    *********Yes, balloons can hover over the earth by using the different directions of wind and different altitudes.



    Can this be done at the same time as climbing to 40k' in a "reasonable" time?

    Very few planes can you take to 40,000ft and jump. But the answer to your question is anywhere from 1,000ft/min and up. It really depends on how much helium is wasted in the free lift. If 20,000lb extra were thrown into a balloon lifting only 2,000lb, it would take off like a rocket ship.

    Not asking how fast a balloon can climb, asking if you can "hover" a balloon over a certain area while at the same time climbing to 40k' in a reasonable amount of time?

    Short answer. No.
    Long answer. Nooooooooooooooo.

  7. bjgraybeal


    Rough estimate. If divided between 10 people, renting suits, and an established business, I would guess $10,000-$20,000. and a company who would do this could reuse the balloon and helium and rent the suits. This would keep their overhead low and possibly lower customer cost.



    A gas balloon envelope that can take "~2000lb" (OP's number) to 60k MSL would be really really big. If you find a manufacturer that will make a re-usable gas balloon to those specs I will give them a gold star. A big high five to whoever pays for it. Who I don't want to meet is the poor ground crew gathering up a few million square feet and thousands of pounds of fragile, expensive balloon.

  8. normiss

    Creepy flashback to county network engineer job I worked for awhile.
    A couple of the women judges are FREAKS!
    One of them, who just loved wearing nothing but lingerie under her cloak was the first person to show me that Adult Friend Finder is a thing.
    Whoa.
    :D:D:D:D
    Damn was she sexxxy.



    Being of the generation where internet porn has been free for as long as it mattered to me I am amazed that this post is not flashing on the side of my page.

  9. ryoder

    Interesting article about people who think they are "Electrosensitive".
    A lot of parallels to the "noise sensitive".

    http://www.theguardian.com/technology/2015/jun/21/the-town-that-banned-wi-fi



    Until I looked that up I would have called 100% KG size and type BS. After reading about it a bit I call 99.9% BS.

    Quote

    “I got the symptoms of radiation sickness,” she told me. Her tone was patient, like a veteran teacher explaining old truths to young students. “I went to the doctor and he wasn’t able to diagnose it. Eventually I established that I was reacting to a buried cellphone tower. US Cellular was the brand – I didn’t react to AT&T, Spring or Cellular One towers.” She reeled off the names as if it would be the most normal thing in the world to have a brand-specific allergy. With her home life increasingly unbearable, she began to travel across the USA and even further afield, to Scandinavia and Nicaragua, in search of somewhere more peaceful. Sweden is one of the few places to recognise electrosensitivity as a disability and the government will help sufferers insulate their homes. “In Scandinavia there were places where electrosensitives gathered, but they didn’t go far enough to prevent the signals,” Schou said. “Farmers still used electric fences for their sheep, or people would use cordless phones.”



    CARRIER Specific sensitivity? ... sounds familiar. :P:)

  10. ryoder

    Interesting article about people who think they are "Electrosensitive".
    A lot of parallels to the "noise sensitive".

    http://www.theguardian.com/technology/2015/jun/21/the-town-that-banned-wi-fi



    "starring at static on tv for hours at a time, listening to washing machines, Did you really think these stories wouldn't get out?"
    ----"I was looking for patterns in the chaos, come on!"
    "It doesn't matter anymore! It's a joke to them..."

    Gold star to whoever can name that movie/book.

  11. If it is a towered or very busy airport you might have to do something civil. But If you can get a truck to the wreck, just tie it on a 20' line and drag it to the other side of the airport. Airplanes are light, especially with the motor gone.

    Oh, and aluminum does burn. Bring a couple 5gal cans and have a party.

    -SPACE-

  12. Sincy78

    Anyone know where I might be able to buy some of these?




    I have a couple of them, I used them in rope rigging for a while. They are not very strong and with any appreciable load they are very hard to release. I recommend. snap shackles or 3-rings.

  13. chuckakers

    *********If she's there specifically to listen to the skydiving noise, as in actively listening FOR it, wouldn't the noise be perceived 'louder' than someone standing next to them who were, say, not paying attention to the circus around them?



    Not if she does her job properly.

    https://www.instrumart.com/products/24262/extech-407732-sound-level-meter

    The only issue I would have with someone using that is I am fairly certain that it just measures any levels of sound, instead of being able to isolate the otter. It's quite possible that a bird or lawn mower or freeway would register a loud enough signal on the meter without being the otter that's flying overhead.

    I don't know squat about audio stuff (yeah, I'm a radio guy and admit that) but I would think a bit of common sense would need to be employed. I also don't think sounds "stack". In other words, if there's a lawn mower nearby giving let's say a 60db reading and then a plane flies over at 100db, I think the device would simply read the same 100db that it would read if the lawn mower wasn't present.

    Either way, the way to do it would be to take several readings to get a typical average and also consider other sound factors in the testing.

    Sound is a wave, two different frequencies (separate noises) do not stack as in 50db+80db=130db, but it can resonate in a particular way that certain waves within two individual 'noises' can 'stack' to increase the power of the noise. Things like a gas engine in a lawnmower or motorcycle could be close to the same frequency as a spinning aircraft propeller and actually register a higher reading. I don't think that would happen in this case, but it could.

  14. VectorBoy

    Interesting. My hang glider belly mount reserve could use those pins. The fairly new reserve and d bag came equipped with two standard curved pins we are all familiar with. The manufacturer told me to fabricate the stows from bungee material kinda like skydiving reserve safety stow material. None of it is TSO'd and actual deployments are slow speed compared to skydiving.


    The system isn't as tight as I would like and an accidental deployment would ruin my day especially while being towed. Another solution would be the sheathed cable method mentioned, I am familiar with this on some crow containers.



    I strongly prefer coated cable with a good 10cm of play, but be sure the handle leash is long enough to extract the cables.

    The only way curved pins work for a PG/HG reserve that I am comfortable with is when the area around the grommets and on the pin cover are velcro, so the pin is sandwiched and held in place by velcro, but easily is ripped when you pull on the handle.

  15. dpreguy

    Before you change the design of a component of a parachute container, don't you think you should run it by the manufacturer?


    nope.
    If I was modifying a harness I would (and I have modified skydive systems quite a bit before[legally] after talking with manufacturers).
    Quote

    Experimenting with a newly
    designed component, (designed by you), is a recipe to create danger for yourself.


    I do this for a living. :P
    I design parachute parts for anything from tiny UAV reserve parachutes to BASE equipment to reverse engineering 1950s ejection seat parachute components. My other job is selling PG gear and teaching speed flying.
    Danger is very relative, and complacency is far bigger a killer than a controlled testing environment where the test pilot/jumper is aware of the situations and potential issues and where appropriate safety systems and backups are in place.