Nov 22, 2010, 12:18 PM
Post #1 of 27
Irvin Delta2 Parawing
Here's some pictures of the Delta2 Parawing jumps we have made over the last few weekends at Langar in the UK. All of these fantastic shots were taken by Tony Danbury.
The red/black, and white/black canopies are UK made Irvin Delta2 Parawings ; the red one is an original Red Devils canopy. The Red Devils Parawings were US made, and were among the first 3 commercially produced versions of this canopy.
The Red Devil canopy belongs to Craig Bulman, who rescued it from the scrap bin around 1992 when he himself was in the Red Devils (The Parachute Regiment Freefall Team). It needed a lot of work including a full reline before it could finally be jumped again.
(This post was edited by andrewhilton on Nov 22, 2010, 12:33 PM)
That strap trailing off the one side is the OSI or Opening Shock Inhibitor. During packing you would wrap it around a series of the coloured lines and then proceed to the next colour. During opening it would release a series of the coloured lines before the next, from front to back, and allow that part of the canopy to fully inflate.
The OSI on the packing pics Beatnick has posted is far longer than the OSI on the canopies I have been using. I think the original length was something like 2 yards, but this was cut in half after some experiences with the openings. The same picture also shows a telfon coating on the OSI to help with the high heat and friction. Not used on the canopies I jumped, and may well have been something that was hard to replace once it was damaged/worn. Beatnick and I have been talking about that lately.
The multicoloured canopy pictures I have are of canopies that have barely been used and have been well looked after ; the Red Devils one had seen a lot of jumps. The photographer knew his stuff too, the coloured lines show up well don't they? I think the white and black one must have scared its original owner and was just stored away. It must have less than 20 jumps on it, the coloured lines are gleaming bright.
For the Red Devils canopy, the lines had all been cut off and I had to make the OSI from scratch too - I used kevlar tandem. This was quite a project, which would have been Beatnicks if not for the owners reluctance to trust the overseas mail for such an artefact, hence it stayed in the UK and ended up with me.
I jumped mine ONCE in it's original length although I don't recall it being 6' long or teflon protected. . JEEZ! It unlocked, unwrapped a bit then hesitated then unwrapped some more then finally got outta the way and opened. I had heard to cut it shorter and did so right after. It helped but I still was anxious about jumping it.
great pics, and memories.. I never jumped one but I wanted to. By the time I had enough jumps they were mostly stored away in closets by then !!! But they looked great ( the jumpers were always pretty nervous about the not great reliability though ! )
the jumpers were always pretty nervous about the not great reliability though !
I am trying to figure that one out. Granted that this isn't a huge sample size but between a friend and my jumps, there is about 100 on the Delta II. We have never had ever remotely an issue with it. I wonder if it had to do with packing and the rush to make another jump. I don't rush when I pack it and make sure everything is really neat.
If I remember correctly, I put 320 jumps on my Delta II without any malfunctions. Although watching that 6' long OSI slowly unwrap was a bit un-nerving. I was a fun parachute, but when you pulled a toggle down too fast, it would sometimes turn the OTHER direction. This was especially bad when you were trying to do a "hook turn".
I concur with it being un-nerving watching the OSI unwrap. But that is some of the fun with the parachute. I have never had any of mine turn in the opposite direction in a hard turn but these parawings do many strange things and their flight characteristics can be altered so easily, I can believe it.
I put exactly one jump on a Parawing...it scared the bejesus out of me. Between the long opening and being very twitchy as I recall, it had an un-nerving tendency to tuck the nose under itself while holding into the wind.
it had an un-nerving tendency to tuck the nose under itself while holding into the wind.
I forgot about it doing that. Usually a few turns and it will do that or like you say holding into the wind. There isn't a lt of pressure there and it is pretty easy to spill the air out. It doesn't seem to matter which parawing either it happens on all of them or at least all the types I have jumped.
I had 120 on my Delta II's without any problema. I had my OSI shortened at the last wrap by Bill Keating along with other Red Devils mods. It was formerely owned by Big Bill Weber I would do stand ups in the peas to piss him of he only cut it away. I loved doing slack line stalls behind your back then let up for it to go over your head and dive below .you. I would do spins where it got below you to.. I still have mine reline shorter and no steering flap like the paradactyl. Never was as much fun the,wish I would have left it alone
Did Francis Rogallo have anything to do with the delta parachute design? Or was it designed based on his work, without him being directly involved? I know his kite designs are very directly linked with hang gliding, as in hang gliding might not exist - or would have much later - had it not been for Rogallo. His delta wing concept was encouraged by NASA at first till they began looking into the Shuttle as a way to have earth (as opposed to water) landings, such as the Russians were doing. And though I don't actually know the era of the delta parachute, it seems close to the time Rogallo's designs were influencing the birth of hang gliding.
Rogallo was working at NASA at the time of the Delta II. His concepts starting the design but the Delta II actually came from another parachute. Originally the Irvin Eagle was out and was a larger parachute than the Delta II. Steve Snyder developed it further with the mods of adding the OSI, stall panels and removing the last section of the parachute making it smaller.
Many of the Canadian Delta II's you can easily see the conversion. The parachute is similar to the US version but a close look there are a couple of differences. The nose and reinforcing being the biggest. Then of course there is the Irvin Eagle stamp marked out and restamped Delta II.
The era of the parawing is harder to answer. The Delta II was mid-60's, Paradactyl mid-70s, Double Keel Dactyl late-70s/early-80s and the PZ-81 (which is a reserve chute) was mid-90s. The design keeps coming back for probably the same reason so many take such an interest in them.
Loy Brydon made the very first manned-jump on a Rogallo design in '66. I saw the article in a link on this site a couple of weeks ago. I also read about it at the time.
Then in '67 ( I 'think' ) Scotty Hamilton made a jump on an Irvin-version of a Rogallo design and wrote about in an article for PARACHUTIST. Irvin had obtained a TSO for that one & it was packed in a sleeve. I talked to Scotty about it a few years later and he said that you had to pull just 'before' you left the step and it still hit you like a freight-train.
IIRC the Delta II would have been very late 60's or so. By then the race was on to come up with something in the way of a 'wing.'
PS) A little OT but I think it was about early '68 that Ted Strong built a ram-air square and was ground-launching it from ski slopes in the NE US. His first design had unequal length lines so that it would be flat across the span, not the curved/arced shape that equal length lines give you.
It might bring some more light to the Parawing history.
In a white paper I've had for years:
FLEXIBLE WINGS FOR MANEUVERING AND LANDING APPLICATION IN THE DE-COUPLED CONCEPT by: G. R. BARTE, JR. General Electric Company Philadelphia, Penn AIAA 5th Aerospace Sciences meeting Jan 23-26, 1967
-Historically, the first base point for flexible wing technology is the patent issued to Mr. Francis M. Rogallo in 1951.
(Rogallo, Gertrude S., and Roallo, Francis M., Flexible Kite, U. S. Patent Office Number 2,546,078, March 20, 1951
-Rogallo, F. M., Lowry, John G., Croom, Delwin R., and Taylor, Robert T., "Preliminary Investigation of Paraglider," NASA TN D-443, 1960.
-Rogallo, F.M. "Paraglider Recovery Systems." presented at IAS Meeting on Man's Proress in the Conquest of Space, St. Louis, Missouri, April 30, May 1-2, 1962.
- Rogallo, F, M., "Flexible Wing Research and Development," -presented at the Symposium of Retardation and Recovery, Dayton, Ohio, November 13-14, 1962
Also in the paper: An all flexible parawing configuration was first flown in small sizes as a kite and glider in 1948.Durng the intensive recent development work on the all flexible parawing, a total of more than 100 manned deployment and flight were made, 57 and 58, initiated by the U. S. Army parachute team and the John F. Kennedy Center for Special Warfar at Ft Bragg, North Carolina. They were favorably impressed by its simplicity, dependability and control.
The all flexible parawing has been successfully flown innumerable times in a 24-ft. (about 400-sq. ft. area) version and has been used for cargo drops. It is commercially available to sport jumpers and advanced versions are now being further tested at NASA-Langley Research Center. (This would be 1966 - 67 time frame [my words]) Ref: #57: Makulowich, 2nd Lt. Michael, "Project Flexwing," Sky diver, May 1966, pp. 18-19
Ref. #58: Hamilton, J. Scott, "Flight of the Parawing," Parachutist, September 1966 pp. 5-9
(As I remember it, I think Scotty was the USPA VP at the time [my words])
This is all very interesting to me because I worked at Irvin Airchute on the Delta II project with Ed Drumheller at the time.
Well, enough from me for now.
Also, check this out: http://en.wikipedia.org/wiki/NASA_Paresev
(This post was edited by SCR216 on Dec 5, 2010, 4:33 PM)
__________________________________________________ Ref: Then in '67 ( I 'think' ) Scotty Hamilton made a jump on an Irvin-version of a Rogallo design and wrote about in an article for PARACHUTIST. Irvin had obtained a TSO for that one & it was packed in a sleeve. I talked to Scotty about it a few years later and he said that you had to pull just 'before' you left the step and it still hit you like a freight-train. __________________________________________________ You got that one right. We jumped that puppy at Taft using a sleeve and when it opened it was like a cannon going off next to your head. My helmet had deep marks on each side from hard hardware hits almost every opening using a sleeve. We then tried an cross between a sleeve and a bag, but that was not good either so the next step was a bag, and that did the tick.
Then in '67 ( I 'think' ) Scotty Hamilton made a jump on an Irvin-version of a Rogallo design and wrote about in an article for PARACHUTIST.
I have an article from Canadian Parachutist when some Canadians were doing test jumps for Irvin Air Chute in Fort Erie, Ontario. They were done in 1966 but that was on the Irvin Eagle not the Delta II.
I was going from memory with the post. So it should be corrected for the Eagle mid-60's and Delta II late-60's. Thanks for the correction.