DBTECH

http://www.square1.com/Catalog/Catalog.html
NEW! BONEHEAD HAVOK Full-Face RW Helmet

I can't imagine this curve making for a one CM shorter riser under tension/canopy.
If your so concerned about this and qualified, do what I did as described in my first post. (Teflon tubing)
(use size/wall thickness specified. I have stock on this size Teflon tubing, and can send you detailed instructions. Or, if you say--"I'm not concerned about severe line twist"---then just leave them out.
Dave Brownell
DB Tech
Mesa, AZ

Apparently you don't know why they are there--if you'd had known, you wouldn't have removed them.
The curve you talk about here is totality irrelevant to riser function, and only a slight annoyance when packing.
Dave Brownell

For riser release, riser cable channel inserts, I use 1/4" OD X 0.032" wall, Teflon tubing.
I make one tack 1/4" to 3/8" down from the tubing/channel top.
Yes, there is a curve in the tubing, but so what?
I believe the Javelins use HD Polyethylene, which is stiffer than Teflon. (also more friction than Teflon)
Dave Brownell

Stainless steel parachute hardware must be made somewhat bigger in cross sectional area because of it's much lower tinsel strength (tinsel in PSI) compared to "heat treated alloy steel."
Heat teated alloy steel (i.e., 4140 @ 40 RC) on the other hand is double the strength of stainless.
(18-8 alloy)
In the case of Rapide links, the only reason that stainless is stronger than steel, is that the steel that is used is low carbon-non heat treated steel.
David Weidner said--
>They actaully have another metal that they're using, also - it's shiny like Stainless,
>but there is no upcharge for it, ask them about it. Note,
>they do not use stainless on the leg straps because the coefficient of friction
>is low, the straps tend to slip on those.
DB--This is electroless nickel plate over alloy steel--looks like stainless
Dave Brownell
DB Technologies

I recommend a product called Carbosol made by Sunnyside for adhesive removal from a container.
It is available in many hardware stores.
The one quart can is white/yellow/blue. It does contain Triclorethelene which is a known carcinogen, but is ultra mild compared to Benzene, which is a big NO-NO. (Yes, Goo-Gone may also work)
Skies,
Dave Brownell

Line stows-line dump
I recommend no less than 2 1/2" bites for the locking stows and not less than 3" bites for the last four stows, with the bands wrapped twice if needed. As far as Tube Stows are concerned, you may want to do a Double Larks head knot, as this will make for a tighter stow without double wrapping the line bite. (see "tighter" or "tightest" on Tube Stow instruction sheet)
Aside from poor line stowing methods, the other negative factors in line dump are large pilot chutes and light weight canopies, as both these factors will mean higher bag acceleration away from the jumper. This results in the stowed lines pulling on the stows harder during bag launch, possibly resulting in their premature release (line dump) if not stowed properly. Large pilot chutes also increase the percentages of fast/hard openings for other reasons other than line dump.
I'm currently jumping an Atair Cobalt 135 with a 21" ZP pilot chute that I made.
(400+ jumps on PC)
I recommend quartering the slider.
Dave Brownell
Mesa/Eloy, AZ

Someone asks:
What are the advantages/disadvantages of the following 3-ring systems :
* mini-ring on type 17
* mini-ring on type 8
* large ring (std ring) on type 8
I am looking to buy my first new rig, it will be mainly for freeflying, but also a little RW.
What would you recommend and why?
DB: Mini ring Type 17 with type 3 reinforcing tape is pretty much the standard now on most rigs.
Mini ring Type 17 Integrity risers are pretty much out.
Mini rings on Type 8 is a configuration that is not recommended by the RWS.
Large rings (std rings) on Type 8 has the highest mechanical advantage and webbing strength/longevity.
Here is one you forgot to mention; it is the configuration for type 17 that is the best, but is rarely seen.
Large (std rings) rings on type 17 mini risers!
This is the best mechanical configuration for type 17, but is rarely seen.
I do have a pair of type 17 risers with standard rings that I built in 1987 that have 400+ jumps on them.
One of the openings was in the category of ultra brutally fast/hard. When I say ultra brutally fast/hard, how does stitches popped on dive loops, deformed delta/stainless connector links and broken lines sound!!
I did not cut away, but had to land with rear risers, as both steering lines were broken!
These type 17 risers with standard rings did not fail on this opening despite not having the type 3 reinforcing tape as used in currently manufactured type 17 risers.
BTW: The canopy was a PD 210. I believe line dump was the cause of this monster opening.
Now jumping a Cobalt 135 on Mini ring Type 17 risers. (I'm 195 OTD)
Dave Brownell
Mesa, AZ

In regard to line dump and openings.
I recommend no less than 2 1/2" bites for the locking stows and not less than 3" bites for the last four stows, with the bands wrapped twice if needed. As far as Tube Stows are concerned, you may want to do a Double Larks head knot, as this will make for a tighter stow without double wrapping the line bite.
(see "tighter" or "tightest" on Tube Stow instruction sheet)
Aside from poor stowing methods, the other negative factors in line dump are large pilot chutes and light weight canopies, as both these factors will mean higher bag acceleration away from the jumper. This results in the stowed lines pulling on the stows harder during bag launch, possibly resulting in their premature release (line dump) if not stowed properly. Large pilot chutes also increase the percentages of fast/hard openings.
I'm currently jumping an Atair Cobalt 135 with a 21" ZP pilot chute that I made.
(400+ jumps on PC)
I recommend quartering the slider.
Dave Brownell
Mesa/Eloy, AZ

Worm Virus among us!
A worm virus has entered dz.com, and has shown it's horrid face when it punched a hole in the home page.
The hole has since healed over, but beware of a second more violent attack when this worm returns from battle on several other web sites. This is a very violent worm that thrashes blindly.
It's also programmed to personally attack skydivers themselves!
The name of this worm virus is:- W95.skygod.hybrid.worm.dll
Dave Brownell

I was down in Florida from July 7 to12 on business at PD--I also jumped at Skydive Spaceland and saw the space shuttle launch at 07:04!
This was my first time in Florida since 1970!
I have to now believe that the state of Florida has the largest "girth" in America; and I don't mean the geographic girth! "Totality gross/huge frontal extreme masses"--300-400 lbs--common.
I could say allot, but it would only be a broken record we've all heard many times before.
Maybe this in an evolution thing---the thinning of the herd!
Dave Brownell
71" @ 174 lbs.
Mesa, AZ

WARNING: Another virus making rounds
Norton intercepted a virus on my computer last night that was in a windows TEMP file called tisland.xix.bat.
The virus was -- W32.sircam.worm@mm
I later deleted it from quarantine, followed by a clean sweep of all files for viruses, which turned up zero.
Computer--so far so good.
Then I got this E-mail
This virus has been wreaking havoc all over the web. Read about it at:
http://www.symantec.com/avcenter/venc/data/[email protected]
Just to be safe, I followed the instructions for virus removal, which included the downloading of a removal file--no infection was found.
As of 7-28-01, this virus has been moved up to a level 4 threat--very dangerous--can delete all files and directories on your C drive.
Keep your virus program up to date people--every week min.
Skies,
Dave Brownell
Edited by DBTECH on 7/30/01 00:46 AM.

It's only a matter of time before "WE" have TOTAL CONTROL
db

Try this-->
http://www.dzsports.net/news4.html

Type XVII webbing is 2500 lbs. minimum breaking strength--not 3600.
TY VIII is 3600 lbs.
Dave Brownell

A friend of mine has an original Centaurus with only 200 jumps on it. (160 nine cell main & a 20 foot round reserve. (Not TSO'd for a square reserve) This rig is in ultra mint condition, and is for sale.
(earth tone colors) (The rig was custom built for him--He's 5' 9" and 140 lbs.) (SF bay area)
The Centaurus was originally built by Troy Lenoy in Colorado. He sold out to North American Aerodynamics maybe around 86-not sure. You can tell by the riser covers--original rigs did not have full riser covers, while the newer rigs had full riser covers.
The original Centaurus was a great rig--I don't have much input on the late model Centaurus, but I would think that John Higgins would uphold the quality of the original rig. Also, the newer rig would be TSO'd for a square reserve.
Just my .02c worth
Dave Brownell
Mesa, AZ
Edited by DBTECH on 7/25/01 00:20 AM.

It should be noted here that bridge day jumps are done from less than 900 feet with zero initial airspeed for a fast pilot chute-bag launch--I know they use larger pilot chutes, but I think you get the point here.
On a good/fast hop & pop done at 75 knots min indicated airspeed, you should be at line stretch thirty to sixty feet below the aircraft. The first second, you only drop 16 feet. At the end of two seconds your total fall is 64 feet. (nominal)
Dave Brownell,
Mesa, AZ
Edited by DBTECH on 7/23/01 10:39 PM.

A "lowest normal" Hop and Pop for myself is 700-800 feet.
As far as an emergency exit is concerned, there are many factors that "I" would "hopefully" consider given that situation. I'd say that range would fall as low as 200 feet, depending on the "total situation."
The model of the "Total Situation" is of course, open for discussion.
Dave Brownell
1200+ Jumps
Mesa, AZ

Congratulations on keeping up on your membership, as I'm not sure how long USPA would allow it to be lapsed, before you would be put back to the zero point!
I received my 20 year certificate in May 2000--Signed by BJ Worth
Skies,
Dave Brownell
Mesa, AZ

American family Insurance will give you health/medical insurance knowing that you are a skydiver.
Not having life insurance, I do not know their policy on that for a skydiver.
They were also the only company that would insure my home built travel/video production trailer.
(for $18K)
They seem like a very informed company.
Check them out, good luck,
Dave Brownell

My Junior fuel dragster of late sixties/early seventies vintage turned high 7's ET at 185-192MPH on 98% Nitro. 301 ci unblown small block Chevy-(750 HP @ 8500 RPM on 98% Nitro)-car weighted 870 lbs!
If I had this exact same car today, but with a Linco two speed trans and current state of the art tires, I would be running in the low/mid sixes, with no engine changes! (MPH--200+
Dave Brownell

Until exit--breathe in through your nose, and exhale the "now humid air" out your mouth, through the helmet vent---works good. This technique purges the helmet with outside air only, and prevents fogging.
Helmet visors tend to remain clear after exit--I believe because of the high airspeed-purging effect.
Dave Brownell

A news stand price of $4.50 is in the upper right corner of Parachutist.
Based on this fact, I would think you could get a subscription only.
A membership in USPA may only be slightly higher.
Dave Brownell

The following is an excerpt of a text that described a sign jump video I did some time ago.
This sign also has a slot/handle at the bottom-center that can be used to turn the sign around in free fall to display the other side, which in fact I did on these jumps.
The sign was "hi tech," in the fact that it was constructed of 1/4" thick hollow tube core Polycarbonate (Lexan), sheet. There is also a wood frame on both sides; on the bottom edge extending 3/4 of the way up on each side. The wood is 5/8" square balsa mitered and gussetted at the two corners on each side.
Eleven #8 screws with T nuts hold the assembly together. The frame also made for a much bigger handle area than just a piece of 1/4" Lexan sheet with slots. This sign is very light for it's great strength and rigidity. It must noted here, that the side handles/slots must be as low as possible on the frame/sign, to assure stability.
Dave Brownell
Mesa, AZ

Geoff asks--
I agree about long bites being better, but why smaller for locking stows?
DB> The "line span distance" between the locking stow points is much less than the span distance between the post locking stow points. This means there is much less line mass between the stow points,--It's the line mass between the stows that causes line dump.
Also, the locking stows are more consistently tighter because of the stretch of the band between the band attachment point and the grommet in the flap, which makes for a tighter stow. Combine both of these facts---ya dig.
In the event of catastrophic line dump at bag launch of the non locking stows, the locking stows would then more than likely "un-stow" before line stretch. (un-stow--as apposed to line dump) This is because of the inertial factor of the mass of the prematurely un-stowed line mass pulling on the locking stow. ('s)
Critical bottom line--Prevent line dump of the non-locking stows with large line bites. Yes, higher band tightens will help, but larger line bites will come closer to balancing the span mass, which is the larger positive factor. As a matter of fact, if the bite sizes were half of the line span distance between the stow points, there could not be line dump even with loose bands, because of equal line mass on each side of the stow!
In the case of my prototype sleeves, I can go with 2.5" bites that do have equal mass on each side of the stow, only because of my "center span lifting loops," but in the case of a standard D-bag, you would need 5" bites which is not practical--and some would say, would increase the chance of a bag lock--but that's a whole other issue.
Dave Brownell
Mesa, AZ