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As Yuri pointed out to me, his last name is pronounced and spelled as "cuts nuts off." Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

hey no problem. i think an intuitive understanding is generally the best understanding. i'll research the issue if anything dramatically differs from these common sense aerodynamics. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

I am confused. My understanding is essentially that the principle is a simle expression relating pressure of a fluid to its velocity, and roughly explains certain aspects of wings, etc. Is there a reference you can point me to confirm your thoughts or mine? My background is not in air flow theory but in atomic theory. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

This is exactly what is being said Gardner. The Bernoulli principle dictates that most of the initial opening stages of pilot chutes and parachutes are from air flow on the outside, NOT THE INSIDE. This fact is well known among the parachute design community. Additionally, a detailed study of round openings will show that the canopy inflates from the top down, and at some point the bottom skirt has opened enough to finish the final stages of inflation. I believe this effect also predominates in squares, inflating from the top down resulting in a generally tail first inflation. Only problem is that the tail has the longest lines and line overs therefore can be a significant risk factor. Therefore, we use items like tailgates, etc to control the tail first opening sequence. Johnny has a point though: knowledge of the very low speed environment is limited and anything that can be done to improve pilot chute performance can only help, obviously. Maybe we should consider adding taschengerts to pilot chutes too instead of just old ratty rounds. I am also skeptical about any analysis of this video. It is just too difficult to see any real detail. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

A little hike will take you to the top of Cerro Torre in Patagonia! Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Does it also look to you that the pilot chute has a bungee cord or something in its design to prevent its inflation until a critical speed, used to collapse the pilot chute while under canopy in the skydiving environment? Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

I'm honored that you and Zennie hold in me such high regard! ;) Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

a word of caution, homeland security has been spotted watching some antenna sites. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

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

The world is now a much emptier place. BSBD, Chris Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

The bumps are at the leading edge of the fin, not on the top or bottom skin of the canopy. They are not like tachengerts, etc., to create turbulent flow. Whales have evolved a semi-regular series of bumps on the front of their fin wing. The front is where most of the drag originates and can the most crucial part of the wing design. Rotating vortices are setup on the leading edge of the whale wing in the vicinity of the bumps. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

I read in Scientific American a few months ago about the effect of bumps on the leading edge of wings. It turns out that whales have evolved fins this way to reduce drag, increase lift, and dramatically increase the performance envelope available with a wing section. A bumpy leading edge can create rotating vortices that cause unusual effects that can be exploited. This concept has created a furor in the aerodynamics community. I believe this should be a long term research item for canopy design; it may or may not be feasible on a parachute but it is nevertheless interesting to contemplate. Quoting some of the results: The sleek flipper performance was similar to a typical airplane wing. But the tubercle flipper exhibited nearly 8 percent better lift properties, and withstood stall at a 40 percent steeper wind angle. The team was particularly surprised to discover that the flipper with tubercles produced as much as 32 percent lower drag than the sleek flipper. http://www.ascribe.org/cgi-bin/spew4th.pl?ascribeid=20040511.071106&time=07%2026%20PDT&year=2004&public=1 Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Tom wrote: Do you think it's necessary to attach the rubber bands to the tail pocket? What if you just used them to gather the lines, but left them hanging free? I see no advantage to using rubber bands to gather lines but leave them hanging free. The point of the tailpocket stows is to prevent sudden line dump. The locking stow at the base of the canopy should prevent premature slider descent that can possibly result in an entanglement. However, no system is perfect and minimal redundancies can be crucial to a lifesaving system such as a parachute. I believe the primary reason people have eschewed or avoided using rubber bands was simply because of effort and the attention required to assemble a system correctly. However, as you know, the rule in parachutes is staging, in order to prevent the many unknown things that can possibly occur. We currently have a system that is pretty good so long as the anti-line dump flap velcro is in good shape and final locking stow is secure, but not too secure. The flap separators seem like an ideal way to go, if manufactured very carefully. I'm rambling... Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Are you using a tailpocket with the anti-line dump flap technology that is standard on both BR and CR canopies (originally developed by Sandy Reid of Rigging Innovations on reserve freebags)? If not, your lines will flow through your velcro causing unnecessary excessive wear on your lines and velcro. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

If extreme sports were a drug, BASE would be crack. Highly addictive, potentially expensive over time, makes the user/jumper do stupid things... Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Get well Robin. Sorry to hear about that. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Line dump from a tailpocket can cause a certain of malfunction, i.e., line entanglement potentially with premature slider descent. People have used rubber band stows with success in cases where "pony tail" rubber bands (very thin breakable rubber bands) are used. The tension created by such a system is generally not enough to torque the canopy during line stretch. I have seen it used very successfully by a few jumpers. If you canopy is turning before completion of line stretch, consider the following options: 1) rotating pilot chute. Consider centering the bridle attachment on the pilot chute or purchasing a apex-vented pilot chute. 2) the canopy is catching some part of the container during lift off. 3) the stabilizers are too exposed and should be 45 degree folded. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

The good ones require a helicoptor Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Ok, Ok, maybe this is site naming but check this out http://www.local6.com/travelgetaways/3793113/detail.html Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Beware, or I shall taunt you some more! Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

qoute: Rather than fly off, he just sat on my canopy for awhile and stared at us, giving us a rather dirty look. This is pretty funny! LOL! Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Yuri is correct about these issues. There is only one subtle detail though that I've noticed when jumping in strong winds with the wind down the wire. First, on exit, you're basically working with a relative wind. I've noticed that my body sometimes will immediately point downwind or will 90 degree turn off that axis. I've also noticed that my canopy tends to open downwind, which can be down the wire if the wind is down the wire. The canopy seems to windsock. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

What comes to mind is this: do you think you'll be more prone to injury given that you don't weigh 100 pounds less? It seems to me that the people who survive with the least injuries are also the lightest. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Having started jumped prior to the invention of the tailgate, I have definitely noticed a significant improvement in opening heading quality with the use of the slider down tailgate. I have noticed the same for other jumpers. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

Hey Nick, the aerobatic jump was from a well known Houston bridge. I'm unfamiliar with the "rodeo" jump shown. I heard BASE 38 refer to the one with Alan H. and George R. as daisy chain. Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174