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kirrz

Reserve as Main?

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This might be a dumb question but I really have to ask it just to satisfy my own curiousity..

Why can't you (or rather can you) use a canopy that is a reserve as a main? What are the technical reasons behind the answer?

Thanks!

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You can use a reserve as a main. Its not going to be your snively main, but its perfectly legal. The main is not TSO'd so if a TSO'd component is placed in there, it doesn't make a difference for the main. The only issue is going to be finding a reserve that has an attachment point for the bridle. I believe Precision reserves do, and PD tandem reserves do as well.

PD will send you a demo of their reserve with a bridle attachment point. I dont know for sure about other reserve manufacturers, but I would guess that they provide the same offer.


Cheers,
Travis

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You can take a reserve canopy and jump it as a main if you like. The "problems" with this are:

* reserves are exclusively non-ZP (i.e. the material commonly referred to as "F-111"). While this is acceptable, and in some ways very good for reserve canopies, for main canopies it tends to result in problems like a weakened flare after a number of jumps (say, several hundred).

* reserves are exclusively (or nearly exclusively) 7-cell. If someone doesn't like jumping 7-cell canopies, obviously this is a problem. :)

* reserve canopies produced to actually be used as reserves won't have bag/bridle attachment points. So you'll either have to sew one on, or use a slider-attached "detachable" bag and pilot chute (something of an exotic method, especially for an F-111 7-cell canopy :)
* reserve canopies produced to actually be used as reserves will need a different slider to promote slower opening.

* reserve canopies are usually made in single solid colors, so if your friends don't know you're jumping a main that looks like that, they may think you've had a reserve ride. :)
* reserve canopies produced to actually be used as reserves won't have packing tabs.

* reserve canopies tend to have lower aspect ratios and be very rectangular, design characterics intended to maximize their chances of opening properly. The cost is what most canopy pilots would refer to as "performance" - turns, glide, and overall flying feel would be worse in many peoples' opinions than on a comparable "sport main" canopy. I should note that some reserve manufacturers will beg to differ, and will say their reserves fly very well. I don't doubt them, but I haven't flown their reserves so I can't say anything from experience either way.

But other than these issues, all of which can be addressed (or in some cases safely ignored), there's nothing wrong with jumping a reserve as a main. There are also some reserve models that are available as a main, so they'll have different colors, bridle attachment point, and a normal slider already. And reserve canopies tend to be cheap.

-=-=-=-=-
Pull.

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* reserves are exclusively non-ZP (i.e. the material commonly referred to as "F-111").



Incorrect. I suggest you do some research on the Raven Dash-MZ. It's a hybrid with both low-porosity and ZP fabric.
Sky, Muff Bro, Rodriguez Bro, and
Bastion of Purity and Innocence!™

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[reply reserve canopies tend to have lower aspect ratios and be very rectangular, design characterics intended to maximize their chances of opening properly.



The lower aspect ratio is more a result of having only 7 cells then it is a design characteristic. All canopies are designed to open properly.

Sparky
My idea of a fair fight is clubbing baby seals

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The lower aspect ratio is more a result of having only 7 cells then it is a design characteristic. All canopies are designed to open properly.

Sparky



I'm going to disagree with you on this Sparky. I believe that aspect ratio is connected to reliability. Lower aspect = more reliable.

This was certainly the view in the early days by the developers of the ram air reserve (Para-Flite), and I believe that more recent canopy manufacturers continue to hold the view that rectangular, with lower aspect ratio makes for better reliability.

-- Jeff
My Skydiving History

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Lower aspect ratio canopies are more reliable during openings. They are less prone to tail flutters and full blown lineovers. (It's why higher aspect ratio 9-cell canopies aren't used for BASE jumping.) I'll also go further and say low aspect ratios are better in case you have to fire them into a mess above your head and they are less wild and easier to control in case they do have malfunction. Old five cell reserves, along the lines of the ParaFlite Safety Star were good, except they are bulky in today's terms and the landings really sucked. However, nowadays people are jumping such small 7-cell reserves the landings can suck anyway.

You have to balance deployment reliability with good landings while keeping in mind you could already be injured before touchdown. If someone built a modern five cell reserve hybrid from newer light weight materials I think it would sell.

BTW, the number of cells has nothing really to do with aspect ration, and I just used 5, 7, and 9 cells to make the point . . .

NickD :)BASE 194

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Our US Military Mt1/ MC series was designed to have a reserve interchanged into a main if needed. That is that once the reserve had like five activations that reserve became a main canopy. Each system had a bridle attaching point and were the same size that way if the jumper had a problem that had to involve a cutaway then the reserve could be used and the mission could still be done. Say a 20,000 feet HAHO. etc..
Kenneth Potter
FAA Senior Parachute Rigger
Tactical Delivery Instructor (Jeddah, KSA)
FFL Gunsmith

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All canopies are designed to open properly.



with varying degrees of success. ever jumped an 11

cell?



>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I have hundreds of jumps on Strong 520, 11-cell tandem mains. They were to best-landing tandem canopies before ZP fabric was invented.
Unfortunately, Strong did not put enough effort into designing the 520. They just took their old 425 main/reserve and sewed on a couple more cells. The worst part was that they retained the old 425 slider.
As a result, 520s opened as fast as reserves and only god's-gift-to-packers could make the openings tolerable.
I tore up more 520 mains than I care to remember!

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The only issue is going to be finding a reserve that has an attachment point for the bridle. I believe Precision reserves do



Raven/Super Raven/Micro Raven reserves have a bridle attachment point. The Raven Dash M does not.

I haven't packed an RMax so I'm not 100% sure, but I don't think they have them either.

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...it is NOT generally true.



My bad. I was reading more into the instructions than was there and thinking of the 40 repack test requirement.

"DEGRADATION FROM USE

This canopy is designed for reserve or emergency use only. It is not intended to be jumped on a regular basis, or to accrue a large number of jumps. In an effort to build the most reliable reserve parachute possible, materials were chosen mainly for reliability and strength, rather than maximum durability over a large number of jumps. The fabric permeability increases with use, causing the canopy to take more time and altitude to open. A canopy with a lot of jumps will not open as quick or land as well as a new one. It is very important that your reserve be in close to new condition. A reserve with fabric over the permeability limits may take too long to open at routine cut-away altitudes, resulting in your death. If you are in doubt about the condition of your reserve, have it thoroughly inspected and have the fabric permeability tested."

PD Series Ram-Air Reserve Parachute Owner's Manual, 3rd Edition 1995

Blue skies,

Jim

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Our US Military Mt1/ MC series was designed to have a reserve interchanged into a main if needed. That is that once the reserve had like five activations that reserve became a main canopy. Each system had a bridle attaching point and were the same size that way if the jumper had a problem that had to involve a cutaway then the reserve could be used and the mission could still be done. Say a 20,000 feet HAHO. etc..



Unless it was a MT1-XS rig. 370 main 270 5 cell reserve.

MT1-XS

Scroll down to "Free Fall Capability"

Sparky
My idea of a fair fight is clubbing baby seals

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Yes, that is true but in general terms of the Mt1-1xx series and the MC-4 series they are inchanged. Back in the days when the HALO main course was at Bragg. You would see at least one to two reserve rides a course, this in turn placed a burden on the SWC riggers who had a problem with replacing all the reserves with new ones so the requirements were raised to five activations.

I can tell you that having just one actavation on one of these big boys made me not want to have another one, unless I had to. Until the materail had time to open up some making the opening a little better. This in turn allowed for a contious resupply of both mains and reserves in the system. Where a worn out main could be replaced with a little bit opened reserve.

My personal MT1 has about 50 jumps on the main and zero activations. Not a bad deal but I see love my Vector three with the skyhook though.

Just my two cents here.......B|
Kenneth Potter
FAA Senior Parachute Rigger
Tactical Delivery Instructor (Jeddah, KSA)
FFL Gunsmith

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Correct!
Raven Dash M was the first version without bridle attachments or packing tabs.
R-Max does not have them either.
R-Max also has a new airfoil, new line trim and a much improved flare. Even when you load an R-Max in the 1.8 pounds per square foot range, it still flies straight and has a decent flare. The only caveat with R-Maxes is to do a few practice flares. For example, the heavily-loaded R-Max - that I jumped last month - stalled when I pulled the toggles level with my diaphram/bottom rib.

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