Talk:Parachute

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Contents 1 Safety 2 Alternative Meanings 3 Components 4 History 5 Alternatives 6 stabilty of a parachute 7 bomb delivery 8 how expensive is skydiving? 9 Andrew Garnerin? 10 Edit 11 Merging with "Ripcord" 12 Restructuring 13 photo 14 paracommanders 15 Drag chutes used on aircraft carriers? 16 Reserve sliders 17 Speed 18 Uses...other celestial bodies 19 This article's integrity was compromised... 20 The Mathematical Contest in Modeling (HS level) 21 Removal of text 22 Malfuntions 23 Varieties of personal ram-airs 24 General characteristics of ram-airs 25 EDITED: Modern Parachutes 26 Criticism 27 Heights 28 Deployment systems

[edit] Safety

damn rite

This can't be right. Does anyone know the correct figure? Kent Wang 00:00, 2 Jan 2005 (UTC)

"1000 hundred"??? - Omegatron 19:38, Feb 9, 2005 (UTC)

The failure rate for static line deployed rounds with an anti-inversion skirt is MUCH lower than sport parafoils. I edited this a while back to reflect a degree of uncertainty and stated a specific type of rig. In addition I added a discussion on how having a reserve affects safety. It's not particularly helpful to try to cite the reliability of a parachute unless you're very specific about the parachute you're talking about.

Since this is an article about parachutes, we should differentiate parachute safety from skydiving safety and discuss primarily parachute malfunctions here. As one contributor points out, the single leading cause of skydiving deaths is not due to parachute malfunction. Failure rates by type of parachute and type of failure would be interesting here. Jumps per death ratios more properly belong in the Skydiving article. Depending on comments here, I'll make these changes later this week. Rklawton 23:03, 4 February 2006 (UTC)

[edit] Alternative Meanings

This page is problematic because it defines "parachute" in terms of vertial parachutes for individual people, when the term has a broader meaning as a drag or lift producing device.

Anyone got better stuff?

Parachute are used in different contexts you're right, I think an expansion may be in order rather than replacement. The original definition is still the dominant one, with drogues etc. often used to describe other applications.

A parachute is also a smoking device commonly used for cannabis...AKA 'lung', it is based on the principle of using a sealed plastic bag to draw smoke into an airtight bottle, by pulling the bag away from the bottle it is attached to. Smoke is pulled in through the neck of the bottle, the only open area of the device. The cap of the bottle is then removed, and the smoke is inhaled by the user, causing the bag to be pulled back inside the bottle.

You may want to add a section and have it disambiguated for this, I'd rather not, let folks find it under drug paraphernalia somewhere, some slang term for a bong in a bag is not justification for a whole section. This is not a dictionary, it's an encyclopedia.

What about other definitions of "parachute"? For example, some people take drugs by wrapping them in tissue paper and then swallowing them, and they call that process parachuting. If this is too uncommon a usage of the word, that's no problem.

You answered your own question. Definitions belong in a dictionary. Articles belong in an encyclopedia. If you want to write an article describing that particular practice, then you'd want to creat a disambiguation page the allows the reader to branch off in one direction or another.Rklawton 22:49, 4 February 2006 (UTC)

[edit] Components

Aren't the lines connecting the load with the canopy called shroud lines? Leonard G. 05:24, 4 May 2004 (UTC)

Yep. Trekphiler 13:22, 3 December 2005 (UTC)

I think this applies principally rounds, modern squares tend to be called suspension lines I think, but I'm not a rigger.

I am a rigger and I've never heard the lines on a modern sports parachute called "shroud lines". "Suspension lines" or just "lines". "Control lines" or "steering lines" for steering lines. Military applications, roundies and cargo parachutes may have different terminology.Skydiver 09:58, 21 January 2006 (UTC)

I believe "shroud line" is an antiquated term still used by the general public and is typically not used in either the military or the sport parachuting community. In my many years as a skydiver/BASE jumper and as an aircraft mechanic in the military, I have never heard the term used in a professional setting. Brienh 04:31, 26 March 2006 (UTC)

[edit] History

By no means am I trying to accuse the contributor of anti-Muslim attitudes, but I'm just curious why the mention of the guy in Constantinople is referred to as "Another Muslim", rather than something like 'someone else'.. pomegranate 14:55, Jan 22, 2005 (UTC)

The primary source simply describes him only as a Saracen. If it had given some clue as to his national heritage, I would have said something like, "an unnamed Turk," or Arab, or whatever. As it was though, he was described only by his religion, or I went with that as the most specific description possible. It is no disgrace to count an early pioneer of flight among one's co-religionists, even if they were unsuccessful. Shimmin 16:18, Jan 22, 2005 (UTC)

[edit] Alternatives

I doubt they exist except for science fiction, but if they have been thought of, they've probably been tried in one form or another... I'm thinking of some movie where freefalling people had rockets that shot down beneath them and exploded at the point where they would land, with the explosive gases filling balloons for them to land on. In video games they have "dropship" type things where the people are rapidly decelerated by a long tube they ride in, which hits and sticks in the ground, etc. etc. Was anything like this ever tried by crazy experimenters? I guess those ziplines that they use to drop troops out of helicopters count... - Omegatron 19:44, Feb 9, 2005 (UTC)

[edit] stabilty of a parachute

Hi does anybody know what factors affect the stability of a parachute? Thanks

Air flow. Rklawton 22:50, 4 February 2006 (UTC)

[edit] bomb delivery

Why is necessary to drop huge bombs with a parachute? Is there too much heat generated from drag otherwise? Twinxor t 22:29, 6 Jun 2005 (UTC)

It's to slow-down the descent of the bomb (especially airburst nuclear weapons, which explode some distance from the ground) thus delaying detonation and giving the dropping aircrat time to get to a safe distance from the explosion. Ian Dunster 10:59, 20 Jun 2005 (UTC)

It's also been used to slow frag bombs so the burst doesn't hit low-flying aircraft, such as the WW2 "parafrag" or (Mk82?) hi-drag. Trekphiler 13:22, 3 December 2005 (UTC)

[edit] how expensive is skydiving?

When I read:

The average skydiver in the U.S. makes about 150 jumps per year and will leave the sport before the 5th year.

I wonder how expensive this hobby gets. But not sure if prices should be included on Wikipedia.

About $20 a jump once you're qualified, maybe $3-6k for a gear and about $2k for student training to get you started. But you can jump rental gear etc.

WpZurp 14:24, 6 August 2005 (UTC)

And I wonder whether such temporary and unsourced information belongs to Wikipedia. Pavel Vozenilek 23:34, 6 August 2005 (UTC)

I think this is info from the USPA, it may be unsourced in the article but it may not be inaccurate. I did not add it, and it does seem of limited value, it should be attributed at the very least.

The pricing information is accurate as of 2005. However, I think what he means is that current price information probably doesn't belong in an encyclopedic article. It will get dated too quickly. If this information is important, then perhaps average cost per jump for each decade of sport jumping might be interesting. On the other hand, price per jump probably reflects inflation and cost of living increases. Readers can get that sort of information from articles about economics. Rklawton 22:46, 4 February 2006 (UTC)

It all depends where you go. http://mnskydive.com has some good rates... you can also get info and lessons from http://yshuaparachute.info

[edit] Andrew Garnerin?

I corrected this. It's André... Trekphiler 22:06, 2 December 2005 (UTC)

[edit] Edit

This was the original:

"The first military use for the parachute was for use by artillery spotters on tethered balloons in World War I. Hydrogen balloons used for spotting were easy targets for enemy fighter aircraft and were difficult to escape from while on fire. To avoid interception, observers would jump from their balloon and descend by parachute as soon as enemy aircraft were seen. The ground crew would then attempt to retrieve and deflate the balloon as quickly as possible. Aircraft crews, however, were forbidden from carrying their own parachutes. Having parachutes onboard was believed to encourage the unnecessary abandonment of expensive aircraft during flight."

I corrected this. Observation balloons were extremely tough, well-protected targets. And it wasn't an issue of how costly the aircraft were... Trekphiler 13:25, 3 December 2005 (UTC)

Weren't parachutes used with observation balloons during the American Civil War? Rklawton 23:03, 4 February 2006 (UTC)

[edit] Merging with "Ripcord"

This article is already 17Kb in size. Adding information about all possible parachute system components would probably make the article too long.

In any case, the "Design" section needs to be re-written; it has information about cargo, sports, aircrew and military parachutes all lumped together. The designs of the different kinds are completely different.

Maybe the "Design" section could be split in to an article of its own, with sections called "General", "Cargo", "Sports", "Aircrew" and "Military"?

Don't merge ripcord, there are many links to components, like slider and 3-ring release system and they should remain separate. Merging like this is a rather silly suggestion, it is useful to have a section of a ripcord for search purposes and additional detail without making the original article too turgid. On the rewrite of the design part, there are only a couple of main designs in use with common components, sure some details change between applications but but it ain't that bad. It really depends how exhaustive you want to be. Rounds are used for people and cargo, and squares are now being used for cargo delivery using GPS. The main differences for the purposes of description lie in the harness and deployment systems (and the scale of things). I'd suggest some restructuring rather than a total rewrite if you insist. Maybe an applicatiosn section? Suggestions?

[edit] Restructuring

I've re-organized the Design-section. Very little information was removed, and a few sentences were added here and there. Someone who knows about cargo-parachutes should include a section about those. Skydiver 10:50, 9 December 2005 (UTC)

I added a bit on deployment systems and switched out one of the images, not because it was better but because the same image of a guy under a round was used twice. Now there's a picture of a C-130 airdrop from dod.mil.

[edit] photo

This article could benefit from a photo of a folded-up parachute in its pack. TerraGreen 17:23, 22 December 2005 (UTC)

I'll add one shortly Rklawton 23:03, 4 February 2006 (UTC)

[edit] paracommanders

The section on the paracommanders (or whatever they are called here - in 20 years of skydiving I never heard that term used) appears to conflict with what I had been told about how they work. I was under the impression they were smaller because of the lift generated by air flowing over the wing-shaped upper surface, not due to increased drag as stated here. Given that they have much less fabric, the claim that they generate more drag seems suspicious. Maury 13:35, 6 February 2006 (UTC)

I seem to remember hearing the same thing; that the distorted shape of a PC produces lift and therefore slows down the descent. The pulled down apex would increase vertical drag, but not the holes! I've removed the sentence. I haven't included anything about producing lift because I'm not sure about the details. Someone who has Poynter's manual handy should check it out and add the relevant information while citing the source. Skydiver 13:59, 15 March 2006 (UTC)

[edit] Drag chutes used on aircraft carriers?

"Parachutes (commonly called "drag 'chutes") can also be deployed from a jet aircraft horizontally from the tail cone at the point of touchdown or shortly afterwards to shorten its landing run, for example if landing on an aircraft carrier....... "

Please provide a citation in reference to use of drag chutes on aircraft carriers. Having worked as an aircraft mechanic (F4-N) in the Marine Corps, both shore based and on an aircraft carrier, I have never witnessed a drag chute used in this way. Aircraft recovery on a carrier is accomplished with the use of a tailhook and arresting cable system. In the event of a failure of the tailhook, a 'barricade' is stretched across the flight deck to bring the aircraft safely to a stop.

Also, it should be mentioned that some aircraft, specifically the F4, use a drag chute for spin recovery in addition to shortening landing rollout distance. Brienh 04:31, 26 March 2006 (UTC)

[edit] Reserve sliders

I've seen BASE rigs with mesh sliders, but I've never seen a skydiving sport reserve with a mesh reserve slider as claimed in the article. Has anyone? Rklawton 00:22, 24 June 2006 (UTC)

I've never seen one either. Many reserve sliders have a large hole in the middle though. Then there is the "bikini" slider which has two triangular holes. Skydiver 16:54, 13 July 2006 (UTC)

I've never seen a bikini with two triangular holes, but I'll keep a lookout. Rklawton 17:02, 13 July 2006 (UTC)

I think older Ravens had a mesh slider.RWgirl 22:53, 23 February 2007 (UTC)

[edit] Speed

I can't find anything about the speed that a parachute slows you down to.80.109.79.136 16:05, 28 August 2006 (UTC)

Speed will depend on what you mean by parachute (which kind and what size), weather, and weight of the parachutist. Rklawton 17:33, 28 August 2006 (UTC)

[edit] Uses...other celestial bodies

Bothered by the wording of the "space" section under usage. Currently it reads: "Parachutes can be also used for soft landings on other celestial bodies. However they do not work on celestial bodies without an atmosphere, such as the Moon. For a soft landing on Mars a parachute alone does not reduce the sinking speed in the necessary intensity and there are always brake rockets or airbags necessary for a soft landing. Soft landings on Venus do not require a parachute, because the extremely dense atmosphere of Venus breaks the descent enormously, even without the use of a parachute. Because of the high temperatures and the limited cooling possibilities of probes, the last part of the descent to Venus is done without a parachute. Landings on Saturn's moon, Titan, are possible using only a parachute."

It certainly seems reasonable that a parachute could not work on the moon, but the wording ("they do not work") implies that this has been tried. Has it? (And, doesn't the moon actually have a very thin atmosphere?) Similar assertions are made for various planets here without clear indications of what is theoretical and what is proven fact. On Venus, the atmosphere "breaks" the descent; I'm pretty sure that should be "brakes." What is the meaning of "Because of the high temperatures and the limited cooling possibilities of probes, the last part of the descent to Venus is done without a parachute"? I would think the point of this sentence is that the last part is done with a parachute; otherwise I do not understand the statement. (And is this actual or theoretical?) None of these statements are cited, nor indeed do I believe there are any citations in the whole article... Darentig 15:40, 1 September 2006 (UTC)

[edit] This article's integrity was compromised...

somebody changed the article and it doesnt make sense now (though it is funny...)

"A parachute is a very unsafe fabric device used to kill the person trying to break through an atmosphere by creating drug. Parachutes are generally used to speed the descent of a person or object to Earth or another celestial body within an atmosphere. Drogue parachutes are also sometimes used to aid horizontal acceleration of a vehicle (a fixed-wing aircraft or space shuttle after running very fast, or a drug racer). The word parachute comes from the French words para,kill or torture, and chute, the fall. Therefore parachute actually means "kill the man in this dang thing". Most modern parachutes are classified as semi-rigid wings, are quite effective at killing, and can be flown as a glider.

Parachutes were once made from silk but these days are almost always constructed from more durable woven nylon fabric, sometimes coated with a - silicone - zero porosity coating to improve performance and consistency over time. Originally silk was used for parachute suspension lines, but was replaced by nylon during the Second World War. When square (aka ram-air) parachutes were introduced, manufacturers switched to low-stretch materials like Dacron or zero-stretch materials like Spectra, Kevlar, Vectran or high modulous aramids. Kevlar is rarely seen except on reserve canopies."

[edit] The Mathematical Contest in Modeling (HS level)

This is very strange. The COMAP Math Modeling contest, for the high school level is a competition offered in November for high schoolers in which a group of up to 4 students spedns 36 continuous hours working on/modeling a mathematical problem.

The questions are available online (the honor system is used; don't look at the questions if you plan to participate and haven't yet) at http://www.comap.com/highschool/contests/himcm/2006problems.html.

Look at problem A. Look at the attached PDF. They shamelessly plagiarized Wikipedia - I mean they copied and pasted, verbatim, pages and pages of text and images straight for Wikipedia. I'm looking at the Copyrights section, especially the Verbatim copying page, and I don't believe they followed these guidelines.

If this isn't the right place to put this, let me know... 24.125.117.4 02:02, 15 November 2006 (UTC)

[edit] Removal of text

I've removed the following text:

The average skydiver in the U.S. makes about 150 jumps per year and will leave the sport before the 5th year.{{fact}}

I think no information is far better than infromation that disrupts the flow of articles, is US-centric in an article of international importance, and lacks a citation , all of which are problems in the text I removed. Graham87 12:20, 19 November 2006 (UTC)

[edit] Malfuntions

Most of the malfuntions listed are malfuntions of round parachutes. Mae West, Inversion, and Cigar Rolls are round malfunctions.

Line twists and line overs are two mals that need to be included. Should there maybe be a seperation of the two types. —The preceding unsigned comment was added by RWgirl (talk • contribs) 22:44, 23 February 2007 (UTC).

I think a separate article is called for. Along those lines, lets examine a general re-organization of these topics while we're at it. It'll help keep the sport/military/non-human use topics in their own buckets. Give this outline a bit of a look and let me know what you think. Rklawton 22:54, 23 February 2007 (UTC)

[edit] Varieties of personal ram-airs

I made a number of small changes to the punctuation and text of this section, hoping to make it clearer, and more grammatically correct. As I know nothing (apart from this fine article!) about parachuting, it might be good if one of the primary contributers were to review my changes for factual accuracy. For example, it wasn't clear to me from the text whether both the leading- and trailing-edge ellipticals were used by sports parachutists, or just the trailing-edge ellipticals. (It wasn't clear what the word "these" in that paragraph referred to.) Fagiolonero 06:39, 19 March 2007 (UTC)

[edit] General characteristics of ram-airs

I have a question about factual accuracy of a small change I made to this section: At the beginning of the second sentence of the first paragraph, is it correct that the problem described regards overly rapid deployment, as I've written? From the text that follows, this seems clearly to be the case, but I thought I'd ask to be sure. Fagiolonero 07:06, 19 March 2007 (UTC)

[edit] EDITED: Modern Parachutes

I've added a few sentences regarding Germany giving their pilots parachutes during the First World War. I've also added two new names:

-Erich Lowenhardt -Fritz Rumey

65.255.130.104 03:42, 6 October 2007 (UTC)

[edit] Criticism

Rounds are rarely used by skydivers these days.

Why?

A "Mae West" is a type of round parachute malfunction which contorts the shape of the canopy into the appearance of a brassiere, presumably one suitable for a woman of Mae West's proportions.

This makes no sense.

Anyhow I came here to learn, so I don't know anything about this subject otherwise I'd fix it. -Rolypolyman 04:21, 11 November 2007 (UTC)

The Mae West bit makes perfect sense to me. The malfunctioning chute looks like two puppies fighting in a bag, ones of which you don't get many of to the pound. Easy. Maikel 14:02, 14 November 2007 (UTC)

[edit] Heights

It would be interesting to include a short list of characteristic jump heights, i. e. for military parachutists, hobby parachutists, high altitude, BASE, supply drops, etc. Thanks. Maikel 14:02, 14 November 2007 (UTC)

You should be able to find that information in the parachuting article. --BennyD (talk) 03:09, 25 November 2007 (UTC)

[edit] Deployment systems

If there is no text under deployment systems, shouldn't we take out the heading? Or could someone add to it? Thanks!--99.244.66.12 (talk) 21:34, 24 February 2008 (UTC)