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I thought Vertigo (Apex now I guess) invented the WLO toggle for slider up line overs. Restricting the tail with a tailgate slider up, so long as it doesn't hangup, should restrict the brake lines to the extent should very rarely result in a lineover. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

X-rays can originate from arcing and bremstralung or so-called braking radiation from the deacceleration of an electron impinging upon a metal target. Arcing can significantly damage hardware in some radiotransmission systems, and will also greatly increase noise of the transmitted signal. Some systems such as klystrons, twystrons, magnetrons, etc... use something called a crowbar when the transmitter (located on the ground, not the transmitting antenna or stinger) arcs to prevent such damage. Arcing should be uncommon and therefore x-ray production should be uncommon. Tthe power on most AM towers is much lower than a TV tower. The chance of arcing and hence x-ray production should be much, much lower for a low power AM system. I think the skin depth may be somewhat deeper than a few mm. See for example http://speech.llnl.gov/thesis/3_2.htm which quotes a few centimeters to a couple tens of centimeters based on tissue measurements of horses and pigs at microwave frequencies. This seems consistent with the behavior of food heating in a traditional microwave oven. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

I've looked at somes articles and I cannot find an appreciable hazard to humans from an exposure to RF radiation. The effect on tissue from RF is heating, which can permanently damage the eyes and temporarily damage the testicles (but a hot bath can do worse). The radiation will become much more hazardous above about 10GHz, especially at 22GHz at a water resonance absorption frequency, and generally for higher frequencies. Fortunately, most towers do not radiate at such high frequencies. I suspect some of the communication dishes do however transmit at such high frequencies, since the directionality of the antenna increases with increasing frequency. These may pose a hazard to equipment and or humans. There was an incident years ago where a jumper's camera fried once while in freefall as he passed a comm dish. The comm dish provided fields strong enough to induce currents in the metal and semiconductor components, resulting in a damaged camera. Notice also the diameter of the waveguide. The waveguide dimensions are comparable to the wavelength of the radiation. A narrow waveguide will generally transmit a much higher frequency. A large waveguide will transmit a lower frequency. I think the real hazard is related to arcing and the subsequent production of x-rays. I believe a transmitter will arc to a person if they stand too close to it. Also, there may be arcing occuring inside the transmitter, which will produce x-rays. This may provide a significant hazard. Arcing will also produce ozone, which is noticable by its distinct sweet humid smell. Some people will say the fillings in your teeth will heat up, etc. This doesn't seem plausible if the surrounding metal is not hot. However, heating of metal on the body or rig and portions of the tower should occur if x-rays are being produced. X-rays will be much more readily absorbed by metal and dense tissue than normal flesh. X-rays are very directional and may be the inadvertant source of much of the urban legends surrounding the hazards of towers. AM towers are a different issue. The absorption of radiation by the body follows the dipole model. Essentially what this model says is that absorption occurs when the wavelength is comparable to the length of the body (or some rational fraction of the wavelength, up to some point). I don't know if hazards exist simply from the small amount of current that flows through the body while on an AM tower, or if the hazard originates from low energy x-rays. The x-ray theory is testable by taking unexposed camera film into various radio tower scenarios. I do have some knowledge of x ray production by equipment that creates VHF and microwaves. X ray production can be a real hazard. X-rays can originate from arcing and bremstralung or so-called braking radiation from the deacceleration of an electron impinging upon a metal target. Arcing can significantly damage hardware in some radiotransmission systems, and will also greatly increase noise of the transmitted signal. Some systems such as klystrons, twystrons, magnetrons, etc... use something called a crowbar when the transmitter (located on the ground, not the transmitting antenna or stinger) arcs to prevent such damage. Arcing should be uncommon and therefore x-ray production should be uncommon. Tthe power on most AM towers is much lower than a TV tower. The chance of arcing and hence x-ray production should be much, much lower for a low power AM system. In case you are curious about the skin depth effect, I think the skin depth may be somewhat deeper than a few mm. See for example http://speech.llnl.gov/thesis/3_2.htm which quotes a few centimeters to a couple tens of centimeters based on tissue measurements of horses and pigs at microwave frequencies. This seems consistent with the behavior of food heating in a traditional microwave oven. These are all opinions and are not definitive. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

In my most Martin Luther King, Jr. voice: I have a dream! I have a dream... I see the day when the kids of base jumpers and park rangers can play together in the same playground. I see the day when base jumpers will talk to their base jumping elders, but never understand the silliness of the discrimination of the park rangers. I have a dream! Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Less chance of lineover, not necessarily a higher chance of better heading performance. This packjob as far as I know predated the tailgate. By restricting the tail inflation, the chance of a lineover is minimized, except for modifications such as the tailgate and Adam Fillippinnoo's (obvious mispelling). Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

it's superman and his great grandfather on this jump! Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

For a first time offense, what is the maximum sentence? I assume its a federal misdemeanor with 6 months max in jail, a few thousand dollar fine, and confiscation of gear. What about the conspiracy charge? How does that work??? Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

jumping naked is so cool. it's like "i'm at one with nature!" however, i don't think it's that common for any particular number. my 100th qualified me for my base number when i finally got my 'S,' as the first jumper at bridge day 1996. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Quote from Zennie: I think a better idea, one which would be respectful to the Navajo and just generally be the right thing to do, would be to have a sponsored event in which the proceeds go back to the tribe for various social causes. - Z Response from me: Super idea. Let's make it happen. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

There is a real chance to get this going. There is some history here. Canyon de C***** was legal with the Navajo nation until two old time jumpers (BASE 37 & BASE 124) ruined legal access by 1) filming a commercial without permission 2) using a helicopter in conflict with agreements with the Navajos 3) using a helicopter in a rescue This was a long time ago and the time is probably right for a respectful diplomatic approach to these Native Americans. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Congrats Duh! Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

I've tried the active ankle system. it's worthless and more likely to injure you. A good pair of boots will probably protect you far more, in my honest opinion. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Jaap Suter is such a cool name... I keep thinking its from one of the Stars Wars films. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

uhh-huhh-huh, you said 'DP' - double ... Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Jaap, until you can stick a good horizontal exit, do not transition to a track too quickly. If you transition too quickly in the subterminal environment and have even the slightest rotation in an exit that should be ideally horizontal or slightly head high, you will tend to pitch head down quickly. For most jumpers, transitioning to a track in one or two seconds doesn't add that much to the total 'flight.' Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

I'm intensely curious about what technologies would require so many millions to prototype. Guesses anyone? -Chris Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

I honestly have no clear cut idea on what the physics are, since I don't have a good foundation in fluid dynamics beyond the basics. One note though: it is widely regarded in the aerodynamics community that the parachute opening is the most difficult and poorly understood problem in aerodynamics. This is the reason there are groups using supercomputers, etc to simulate such processes. See for example http://www.mems.rice.edu/tafsm/ And for a description of how a round opens: http://www.mems.rice.edu/TAFSM/PROJ/FSI/axi_para.html The primary issue in my mind is obtaining reliable data. I worked with a physicist from U.C. Berkeley and Lawrence Berkeley National Laboratory who once described an ultrasound positioning system that would be ideal for charactering an opening sequence and the subsequent flight sequence without affecting either opening or flight. That added with other sensors such as pressure (and other things) would be first steps to understanding these issues ... and resolving many of the current debates. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

It's simply enough: add a tension datalogger on the bridle for the same pilot chute with large mesh, marquisette mesh, and with and without tashengerts (sp?), in a controlled environment such as a launching system on a vehicle at deterministic speeds. ya know? Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

The micro lines seemed to have worked for him. Microlines have tradiationally been avoided since they don't stretch nearly as much as dacron. The lack of stretch can overstress specific regions of the canopy, and can in some cases enhance the asymmetry of the opening. I don't see any significant problem with any of his setup though. The only issue that stands out to me is protective gear that has a line snag potential. Much of this gear can be worn beneath the clothing. There are reasons why people are leary of wearing open hooks on their shoes or boots (death hooks) when jumping - parachute line snag potential. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

The best technique I've seen for drying a canopy is to hang it from the tail (out of the sunlight - no UV). Nick raises a good point. I suspect the amount of deformation of the canopy and the amount of increase in permeability that results in the drying process is minimized with slow gentle drying. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

The salt is harmful not because it eats your gear but because it eventually recrystallizes and becomes very abrasive to the canopy. Put the canopy in a large bucket afterwards and run a fresh water garden hose continually into the bucket. Taste the lines or canopy for salt on occasion. Once the gear is salt free, handle the wet canopy very very carefully. The permeability of the fabric is determined by the spacing of the nylon threads, and these are forced together during a manufacturing process known as calendering. When the canopy is wet, it becomes so heavy and unwieldy, that it's easy to pull hard enough in some locations to damage the canopy and further increase the permeability (by further spreading the spacing between the threads). Of course, when the canopy gets wet, it absorbs moisture and bloats. During the drying process, it doesn't necessarily shrink uniformly, leading to an increased permeability. However, this shrinkage may be more noticable among various canopy tapes, which can slightly affect your airfoil. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

In my best Beavis and Butthead voices "huh-uhh-huhh-huh..." You said 'get in.' Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Is this a long time jumper with the initials K.N. ? Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

The only common thread I've found among the jumpers is that they are generally stress seekers... and most do not like to golf. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

From this point of view, I would think they were 11 years old! Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174