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Jumped a 55 year old 26' Navy Conical

 


pchapman  (D 1014)

Nov 18, 2012, 5:00 PM
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Jumped a 55 year old 26' Navy Conical Can't Post

Yesterday I jumped a 55 year old canopy, a 1957 26 reserve, a Navy Conical I think. Bill Cole and I think it probably was once one of his, that he dyed yellow as an attempt way back when to see if the dye would reduce porosity and descent rate. (I can't rule out that it could have been used as an airshow cutaway canopy later on too.) It has seen some service, with a replaced line and a bunch of patches.

Descent rate was about 20 fps down low, based on video timing vs. alti checks. Yes I was a little apprehensive! (When I did an alti vs. watch time check up high, I had blown through 1200' in well under a minute. Even without doing the exact math, I knew that didn't sound like much fun.)

The canopy was worn as a 3rd canopy on my belly, on a second harness. That way I could both watch the deployment and have no worries about chopping it if I didnt like how it flew. But it did mean extra weight and a lump on ones back when trying to land a round.

When a pilot chute has as weak a spring as an ancient MA-1, then it isnt bad to have the canopy in sight while it deploys! The opening, after a 3 second delay from a C-182, was quick enough on video but at the time it seemed rather slow: I pulled the ripcord, nothing happened, I assisted in pulling open the flaps, the MA-1 bounced in the burble and bounced off my face, and finally about two seconds later started to pull the canopy away.

No wonder jumpers had to protect their Capewells when cutting away with a belly reserve in the old days.

The canopy sure flopped around in my burble as the MA-1 extracted it. One thing that was worse than even the old days was that elastics were on bights of line but not attached to the belly container's tray, reducing the little bit of staging that provides.

Canopy inflation was good, pretty symmetrical, with just a little extra dishing on one side (when looking at video frames). It's an undiapered round of course but with the low speed the opening wasn't hard.

Rebound: There was some good wake recontact after initial full inflation. It happened so fast I didnt notice at the time but its clear on video. About a third of the canopy deflates and one line group goes all slack before second full inflation.

Canopy performance was poor, with seemingly very poor forward speed, despite having been "modded". There were 3 traditional vents at the back, which later had been meshed in too. I thought the mods would give good stability, but occasionally the canopy would randomly rock forward and back in an oscillation -- which suggests it wasn't consistently spilling air out the back and flying forward. Or perhaps even the slightest touch on the risers, to start a turn, might disrupt its normal flying and cause it to rock some seconds later. Not sure exactly what was causing the issue. Turns with rear risers were slow but worked.

The oscillation was not nearly as bad as what one sees in old videos of flat circulars, and only occasional. But it unexpectedly rocked back a few seconds before impact, so I ended up getting dumped on my back on landing instead of getting in the proper PLF I wanted in the low wind conditions. The impact wasnt that bad but there was a little whiplash.

For those on facebook, a bunch of pics are at http://www.facebook.com/...855495656&type=3

For just a quick look, Ive uploaded a few pics here.

I don't feel any burning desire to jump the canopy again; I think it'll be donated for a kid's room decoration next.


(This post was edited by pchapman on Nov 18, 2012, 6:16 PM)
Attachments: 1957 26ft - messy extraction.jpg (147 KB)
  1957 26ft - decent inflation.jpg (176 KB)
  1957 26ft - wake recontact on opening.jpg (58.0 KB)
  1957 26ft - Peter Chapman (Nov 2012) - oscillation on landing.JPG (222 KB)


RobertMBlevins

Nov 18, 2012, 5:37 PM
Post #2 of 22 (3090 views)
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

You might want to re-post this one over at the infamous DB Cooper thread next door. Supposedly, Cooper jumped a 26 or 28 foot round (depending on what version of the story you support) out of an NB-6 container. I would add the pictures, too.


matthewcline  (D 21585)

Nov 18, 2012, 6:06 PM
Post #3 of 22 (3079 views)
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Re: [RobertMBlevins] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

In reply to:
You might want to re-post this one over at the infamous DB Cooper thread next door. Supposedly, Cooper jumped a 26 or 28 foot round (depending on what version of the story you support) out of an NB-6 container. I would add the pictures, too.

Kind of an apples and oranges comparison though.

Cool jump though PC!

Matt


councilman24  (D 8631)

Nov 18, 2012, 7:41 PM
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

What was exit weight?

I looked for years for a Phantom 28 that was cheap enough. I finally found one and jumped it in 2005, with about 240 lb exit weight. I planned on landing in the grass but hit the pea gravel. Was glad I did. Hadn't jumped a round since I busted up my leg in 1987 and put on a bunch of weight using a cane.

I've got it and several others ready for jumping.


airdvr  (D 10977)

Nov 18, 2012, 7:47 PM
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Re: [councilman24] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

Takes me back to the days when you knew someone had a mal.


lekstrom10k  (D 3001)

Nov 19, 2012, 2:21 AM
Post #6 of 22 (3018 views)
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

I made many jumps on mine as it was rhe only steerable tri vent surplus you could get. Other than a 23 tri-con and the 28 foot front mount suitcase. With the ropes and rings squares you needed a good reserve.. My next favorite was my Strong 26 Lo-Po. That was much laterthough when I had my "Unit" that I parted company wiyh many times . Back yo back 4 times over our companionship.


pchapman  (D 1014)

Nov 19, 2012, 5:26 AM
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Re: [councilman24] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

Exit weight I should have mentioned: about 185-190 lb with all the gear. I'm glad I'm still reasonably skinny.

Edit to mention more about container design:

No kicker plate was used, although the pack job was tight. No bungees on the belly container. So those are additional reasons for the weak pilot chute to launch even worse.

(The belly container is a modification of the main container that was hacked off the 1980's rig that furnished the 'cutaway harness'. It has been mainly used for ram airs as cutaway canopies, and not specifically for rounds. Instead of a kicker plate these days, the way to do things would be a kicker flap, like in modern sport reserve containers or I think the T-10 MIRPS belly mount.)


(This post was edited by pchapman on Nov 19, 2012, 5:45 AM)


AdD  (D License)

Nov 19, 2012, 7:16 AM
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

20 fps! You are tougher than a $2 steak Peter.


blongb  (D 2717)

Nov 19, 2012, 8:35 AM
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Re: [AdD] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

Nice! I remember deploying my 26' conical at 500' following my messing around with a total (bent pin on a very low exit). Enjoyed watching the excellent fast deployment; had no time to play with steering or to judge decent rate. It was a less than terminal landing, so it was all good.......
Thanks for bringing back that memory!
Bill


(This post was edited by blongb on Nov 19, 2012, 8:36 AM)


Niki1  (D 3103)

Nov 19, 2012, 9:17 AM
Post #10 of 22 (2937 views)
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

I used a 26' conical as a main for about 100 jumps because it packed a lot smaller than PCs, Strato Stars, or even my Starlite.
I put a center line on it. The apex was pulled down to the skirt, it had crown lines and even a couple of turn slots on each side. It had about as much drive as a wind drift indicator. But it packed really small and it let me make the next jump. That's a parachutes main job, after all. Wink

1957 or 1958 Navy conicals had a bad batch from one manufacturer. (Switlik?) The story I heard was that they were shipped in a rail car that had been used for some kind of fire retardant. The canopiesd blew up pretty often.


steve1  (D 23640)

Nov 19, 2012, 9:54 AM
Post #11 of 22 (2927 views)
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

26 coni's were supposed to be a great reserve, back in the day. Most of us felt they were a lot better than the 24' round.

I may be in the market for one, when I get back to jumping again. I've been grounded for a few years.

I have an old P.C. that needs to be jumped. I'd like to find one, still in good shape, in a chest pack.

I think I'd be scared to jump one that was 55 years old.


chuteless  (D 41)

Nov 19, 2012, 10:28 AM
Post #12 of 22 (2918 views)
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

Thats a good photo of the conical, Peter.

I have never once jumped a square reserve, although I have had a round reserve out about 10 times...well, actually 9 times, because I once cutaway my reserve and opened my para-commander.

There is nothing like a round as it inflates above you like a giant flower....what a pretty sight.

Bill Cole D-41 Canada


councilman24  (D 8631)

Nov 19, 2012, 11:53 AM
Post #13 of 22 (2882 views)
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Re: [AdD] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

Wait till you land under that 126 unconscious. That will be tough.Tongue


NovaTTT  (D 17887)

Nov 19, 2012, 5:44 PM
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

Nice, Peter. Probably better you landed on the gear and not your feet!

FB unavailable. :-(


pchapman  (D 1014)

Nov 19, 2012, 7:00 PM
Post #15 of 22 (2823 views)
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Re: [NovaTTT] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

In reply to:
FB unavailable. :-(

Hey Nova, FB is convenient for uploading batches of files, but has the issue that the viewer must have an account and be logged in. That's still needed even when someone leaves their uploaded photos on the default (?) setting of "Public". No friending necessary, but logging in is required. If that's a problem for anyone who really wants more photos, bug me and I'll get them to you somehow.


More trivia about the canopy:

-- The MA-1 was a little newer, 1958, built by "Jayval of New Mexico".

-- Today I pull tested the Navy Conical, having only thumb tested it prior to jumping it. Two spots were OK at 35 lbs. Another spot I tested to destruction, and it tore at 41 lbs on a pretty accurate scale.

That's actually pretty impressive given that the old Type I fabric* is only rated to 42 lbs minimum strength when new. I acknowledge that nylon will chemically slowly degrade over time, but this is one data point showing old does not necessarily = weak.

-- From looking at prior damage to the canopy, it had led an eventful life:

Some patches on the canopy retained the original material inside, where one could see the damage wasn't poke holes from landing in a tree, but sometimes had scroring leading up the the 1-2" holes, and/or fuzed thread ends at the tears.

In other words, I think the canopy had gotten a bunch of friction burn holes at one time. Plus one line had been replaced, being normal white instead of the yellow that everything else had earlier been dyed.

So at some point a jumper had an exciting ride, perhaps on a high speed opening, burning a bunch of holes in their undiapered round reserve!





* according to Poynter's,
MIL-C-7020 Type I was used in the Navy 26', Army C-9 etc, and has 80-120 cu ft/min permeability, so it was effectively high-po before LoPo came about.

While PIA TS-108 says to test to 40 lbs, that's pretty tough on a fabric only rated to 42 lbs, when the later George C. Harris F-111, the real stuff, was rated at 45. So I think 35 lbs is a reasonable test for older materials.


Krip  (Student)

Nov 19, 2012, 9:03 PM
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Re: [steve1] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

In reply to:
26 coni's were supposed to be a great reserve, back in the day. Most of us felt they were a lot better than the 24' round.

I may be in the market for one, when I get back to jumping again. I've been grounded for a few years.

I have an old P.C. that needs to be jumped. I'd like to find one, still in good shape, in a chest pack.

I think I'd be scared to jump one that was 55 years old.

Hi Steve

I look at it like this: that 55 yo coni has the same DOM from back in the day. We've grown old together but if we've taken care of ourselves we're still servisable. More or less.

Some peeps have been hitting the bottle, drugs, couch, twinkies for 55 years and have issues.

Peters last post gives objective quantative numbers for the 55 YO ripstop coni strength.

Don't worry be happy find a coni that wasn't used as a car cover, and stored correctly have it strength tested by someone you trust.Than make your decision.

What could go wrongLaugh

BTW MY trapping this winter is going good, 3 big ass ratsTongue

R,


councilman24  (D 8631)

Nov 20, 2012, 12:54 PM
Post #17 of 22 (2752 views)
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

Now you have to patch it before you make it your regular main.Wink


SEREJumper  (D 29555)

Nov 20, 2012, 8:38 PM
Post #18 of 22 (2707 views)
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

Great post Peter, thanks for sharing!


SCS292  (No License)

Nov 21, 2012, 6:17 AM
Post #19 of 22 (2677 views)
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

"In other words, I think the canopy had gotten a bunch of friction burn holes at one time. Plus one line had been replaced, being normal white instead of the yellow that everything else had earlier been dyed.

So at some point a jumper had an exciting ride, perhaps on a high speed opening, burning a bunch of holes in their undiapered round reserve! "

I had a what we called a garbage malfunction on my PC and cut away somewhat low and opened my 26' conical for the first time. I thought it was a perfect deployment since I had both ripcords in my hand (no beer buying penalty) and I saw my kicker plate frizbeeing off. I thought I would just follow the kicker plate and not have to buy anything. Just as I finished that thought I began to spin and when I looked up at the canopy again I had a May West and the canopy was full of silver dollar sized holes. About a quarted of the canopy was tucked in with two lines over. I didn't have a knife so I tried to do the burn trick but the ground was becoming an issue. I pulled in a similar amount of canopy in the adjacent quarter and stopped the spin just as I landed in a freshly plowed field. I never felt the ground. I weighed 150 at the time. I was really glad to see PCs third photo labeled "Wake Recontact". Back then, 1972, the theory was that the canopy "pancaked" and that the pilot chute looped under two lines and redeployed the whole canopy, pulling it under the two lines, thus causing the burn holes. Of course I always suspected the rigger and everyone else suspected I did something wrong, but from PCs photo I can see how it may have happened. Anyway, over 100 jumps and only two malfunctions isn't bad, unless you have them both on the same jump.

My canopy was white but I sold it to a friend who used it for practice cutaways and I have no idea where it may have ended up.


(This post was edited by SCS292 on Nov 21, 2012, 6:21 AM)


efs4ever  (D 7014)

Nov 22, 2012, 2:28 PM
Post #20 of 22 (2600 views)
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Re: [pchapman] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

Brings memories. My first jump was on a Yellow C-9


WGore  (D 3379)

Nov 27, 2012, 6:19 AM
Post #21 of 22 (2404 views)
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Re: [efs4ever] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

  I've made quite a few rides on a Navy Conical modified and non modified and it beats the devil out of a 24 flat.

The problem IIRC with the conicals was a chemical treatment of the fabric to make it a duller white. They only used it in 57 and 58 and discovered it caused the fabric to deteriorate at a faster rate. I had one of the affected canopies and checked it regularly and it eventually failed the tensile test.

Before the low-pos came out it was the way to go. Packed smaller that the 24 flats. Out of 14 mals only one was on a 26 Phantom, one on a 24' Twill, one on a 24' Flat, none on a square.


airtwardo  (D License)

Nov 27, 2012, 2:57 PM
Post #22 of 22 (2360 views)
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Re: [WGore] Jumped a 55 year old 26' Navy Conical [In reply to] Can't Post

In reply to:
I've made quite a few rides on a Navy Conical modified and non modified and it beats the devil out of a 24 flat.

The problem IIRC with the conicals was a chemical treatment of the fabric to make it a duller white. They only used it in 57 and 58 and discovered it caused the fabric to deteriorate at a faster rate. I had one of the affected canopies and checked it regularly and it eventually failed the tensile test.

Before the low-pos came out it was the way to go. Packed smaller that the 24 flats. Out of 14 mals only one was on a 26 Phantom, one on a 24' Twill, one on a 24' Flat, none on a square.


Yup...I had a '57 as my 1st reserve, it rode nice enough but I got a like new 23' tri-con really cheap instead. I was told with my size & weight it was a better choice.

I cut the lines off the Navy and hung it from the ceiling of every place I lived in during college...boy could THAT canopy tell some stories! Blush



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