Post round pre squars

[steve1 5]

Thanks Jerry and Howard,
After all these years I finally know what a crossbow canopy looks like....

[lucky508 0]

I have a 26’ Crossbow reserve from Security. I’m guessing this is the reserve that came with the complete system correct? It has no mesh in the drive slots or diaper. I have a pic of the data panel from the last time I packed it. The pic is on my other computer and I’ll post it later. I have it packed in a chest reserve. The volume is much lower than even a 24’ T-10R.

Cael

[riggerrob 558]

Yes, I have packed several Crossbow reserves.
They were conventional 26 foot diameter conicals.
The oldest Security reserve - that I packed - lacked mesh in the drive windows. Instead, the drive windows were criss-crossed with tapes.

[JerryBaumchen 1,048]

Hi lucky,

That Security 26 ft Lo-Po that you have is in the original configuration of that canopy.

What Rob is describing is a later version. Then, even later, they changed to the mesh covering for the drive slots.

During the entire life of that canopy they also added the 'normal' diaper & what I call a Flat Diaper for when they used the canopy in their SafetyChute.

Security made a lot of small changes to that canopy over the years; probably more than any other TSO'd canopy.

JerryBaumchen

[slots 0]

I was very interested to read Jerry Baumchen’s account of the LeMoigne idea of using formed panels to direct air out of a round canopy, and how Dan Abbott designed a “copy” of the LeMoigne principle using flat panels.

Back in the 80’s I gave a lot of thought to the radical difference between a flat circular canopy and a LeMoigne type. Realising that the shaped panels not only provided drive but also lift I wondered if there was a way to have more of these shaped panels. Not on a round parachute there wasn’t, but parachutes don’t have to be round do they?

I came up with the idea of getting shaped panels out of flat material on a single layer square parachute, first of all by also using the Derry Slot principle, but in a horizontal plane rather than near vertical.

The first one was made of just five flat panels as shown in the drawing, Fig 1. All the lines shown in the drawing are where the panels are reinforced with tape. Each panel is joined to the next one ONLY where the arrow heads are shown, and on the curved ends which formed the stabilisers. The black dots mark the rigging line attachment points. The front (upper) four panels only have rigging lines on the leading edge which is pulled down, but the trailing edge of the panel in front billows upward to make a shaped panel like the LeMoigne type, but from flat material more on the Derry Slot principle.

This parachute became known as Slots, later called Slots 1. It was twice dropped from 500 feet with a sand bag load, then live static line jumped from 4,000 feet and landed safely first jump. I had over erred on the side of caution and Slots 1 was in fact far too big so a smaller Slots 2 was built using six panels, four lift panels and two flat stabiliser panels.

A further development was Slots 3 with six panels exactly as Slots 2, but these panels were only joined to each other directly at the stabilisers. They were joined indirectly by a 6 inch tape at the entire mid canopy line attachment points.

Slots 3 was very successful being cleared in the U.K. for use as a main parachute by D licence holders. It was used many times for display purposes into restricted areas without any problem. It was perhaps 20% faster than a PC, turned quicker and only had about 60% of the bulk.

Slots 1, 2 & 3 were the first parachutes I made. Slots 1 was first jumped in April 1980, Slots 2 was first jumped in November 1980 and Slots 3 in October 1981. Those dates tell you why you have probably never heard of them. They never went into production because Ram Air parachutes had already taken over. Slots 3 was loaned to Rigging Innovations for evaluation and later to Pioneer Aerospace.

There are two Slots 3 canopies still in occasional use such as at the Vintage Weekend at Teuge in the Netherlands every year and I understand a rigger in Canada is building two more for fun use.

Dick Gays, U.K.

[lucky508 0]

Thanks to Riggerbob and Jerry for the info. I think I'll sew some mesh into those drive slots.

Cael

[pchapman 261]

"Slots":
Great to see new pics and hear the history from the designer.
I had seen the Teuge pics but little information was out there about the canopies.

(Interesting too that even a main canopy had to be approved for regular jumper use in the UK. Does that sort of regulation still apply?? )

[Hammitt 0]

I started jumping in 1973 and by then XBO's and TBO's were a rarity. I remember seeing a TBO at Pope Valley probably in October 1973. That was my first visit to Pope Valley.

The only person I remember jumping a XBO at that time was Leon Delisle. If I recall correctly, Leon bought it from Mike Truffer. He didn't jump it much as it seemed to have a mind of it's own. Seems like they were very hard to keep in trim. This was a problem that PC's didn't have. I remember Leon going to a Black and White PC soon there after.

[nitrochute 2]

around 1965 Lew Brooks(D977)borrowed a crossbow from either Bill Fabrey or Jim Stewart( 2 navy guys stationed at Lakehurst NJ) at snyders dz in NJ. on opening, all 4 steering toggles broke loose from the risers leaving Lew with no way to control the canopy except for risers.the crossbow sarted making turns all by itself and Lew had to use all his strength to stop the turns. he lost altitude awareness and by the time he decided to cutaway, he was at 500 ft or less( and exhausted from countering the turns) To say the Crossbow was unstable would in my mind be an understatement.

[slots 0]

I don't know the current rules having left the sport some 16 years ago. At the time the British Parachute Association required all parachutists to wear two parachutes made by "an approved manufacturer”. As I was not an approved manufacturer, not a rigger but just a Do It Yourself bloke, for quite some time I had to use whatever I was testing as a third canopy in a cut away rig.
All together I made eleven parachutes, none of them suitable for production at the time they were designed. i.e Slots might have been several years earlier. The other parachutes of mine that were perhaps interesting where my three “Parashapes”.
These were an attempt to copy the hot air balloon special shapes for advertising purposes. Parashape 1 is “WALLY”, made for the Wally Gubbins videos made by Leo Dickinson. Foolishly I made WALLY to read correctly from below and since it was far too dangerous to land it, taking photos from below was nearly impossible. Photos taken from above did not read correctly unless reversed and this put the jumper OVER the canopy instead of beneath it.
Parashape 2 is The Olympic Rings, made with the intention of stealing a little bit of the Americans limelight I knew they would achieve at the 1988 Olympics. This did not happen as this was a very difficult parachute to get to fly right, several modifications being required. When it was right it still had a very high malfunction rate and we ran into copyright problems. Despite the fact that it oscillated wildly swinging the test parachutist through quite a large arc (it had to have VERY long lines) it was once landed safely.
Parashape 3 was made with the intention of having a safe Parashape that could be landed in reasonably calm conditions. Looking for a suitable shape I finally decided on the either the Volkswagen logo or a POLO mint. (If POLO mints are unknown to you, they are a small round sweet (candy?) with a hole in the middle). A photo of a 6’ diameter model made to test my ability to add the words “POLO” is attached. After the copyright problems with the Olympic Rings, VW and Nestles (who made POLO mints) were approached for permission. Nestles declined, VW gave ascent. This was handy as the VW logo reads correctly from above and below. I made thirty odd jumps on Parashape 3, safely landing on all but one occasion when jumping in high wind for Leo to film.
All the Parashapes were single skin canopies, but a second skin was added to Parashape 3 to see if it was possible to reduce the bellowing between the rigging lines to clean up the shape. Since this second skin had to have holes to let the air in, where these coincided with the drive or turn slots it gave the appearance of having eyes (see photo).

[mircan 0]

amazing!

dudeist skydiver #42

[steve1 5]

Thanks for the great photos Slots. I've never seen parachutes like that....

[muff528 3]

Are you sure "The Right Wally" and The Wrong Wally" are 2 different pics?

[slots 0]

No, The right Wally is at it really appeared, the wrong wally is the same picture flipped. As I said "Photos taken from above did not read correctly unless reversed and this put the jumper OVER the canopy instead of beneath it."

[sprtdth 0]

Quote

Thanks to Riggerbob and Jerry for the info. I think I'll sew some mesh into those drive slots.

Why on earth would you want to do that? The inverted T cut out is for drive (the center gore) and steering (the small turn windows). Cover those up with mesh and you'll find (just like we did in Taft in the early '70's) that you loose about 50 percent of your performance.
Think about it, make "holes" to let air out then cover them back up????
Just my thoughts.

CRW Skies
Frank
CRW Diva #58

[howardwhite 4]

And speaking of Teddy Mayfield...

http://www.registerguard.com/csp/cms/sites/web/news/cityregion/24367930-41/mayfield-faa-1994-eugene-license.csp

HW

[steve1 5]

I knew of some fatalities at Sheridan, but I had no idea that there were 13 people in all, who went in.

I jumped there once without log books or anything else, after about a ten year lay off. I went to Ted and told him I wanted to jump. Next thing you knew I was on a Beech load with a rented rig.

You couldn't help but like the guy....

[bozo 0]

Quote

I knew of some fatalities at Sheridan, but I had no idea that there were 13 people in all, who went in.

I jumped there once without log books or anything else, after about a ten year lay off. I went to Ted and told him I wanted to jump. Next thing you knew I was on a Beech load with a rented rig.

You couldn't help but like the guy....

----------------------------------------------------------
Teddy was my Tandem IE long long ago. We paid his airline ticket and put him up in a motel and fed him of course while he certified a half dozen of us.
The only problem was that ole teddy had forgotten all his ratings had been pulled prior to his visit with us.
I was doing 12 to 15 tandems a weekend when I got a nasty letter from both USPA and Booth telling me that my rating was no good and to cease and desist.
So I had to do it all over again and pay the fees all over again....yeah.....you couldnt help like the guy, my ass.

bozo
Pain is fleeting. Glory lasts forever. Chicks dig scars.

[steve1 5]

I think many of us have a Ted Mayfield story or two to tell. The guy always treated me right, so I think I'll keep quiet....