Needs to be revisited. Although I like all of the complex ideas given, one simple suggestion is that *air travels upward* (floats). It's unlikely the car would rest itself on perfectly level ground. If you could use the tire farthest upward you could use the angle to get the air to travel up into the mouth where it collects at the back of the throat (pushing the water out) and you can take deep breathes from that. Hence why jacuzzi breathing is easy (i did it too)...you're above the air.
I LOVE THIS MYTH BUT THINK MORE CAN BE DONE TO PROVE THIS CAN BE DONE. I have two very good suggestions to possibly make this myth work. First, use a bag to catch the excaping air from the tire (cut a bunch of holes to speed this up). Seeing that the air is escaping from the tire means that the pressure inside the tire exceeds the ambient depth pressure (no water is going into the tire the tire pressurized. The escaping air should displace the water in the bag and Adam should be able to stick his head into the bag and breath (exaclty like the old diving helmets). This should work seeing that the escaping/trapped air will be pressurized equal to the depth pressure of the surronding water which is also pushing on Adam's lungs. Without this pressurized air, the water pressure, even at 10 feet (4.4 psi) will exceed the lungs/diaphram's strenth to "inhale". This is why you can't breath from a garden hose while more than a few feet underwater (Great Myth suggestion). However, this will lead to ALOT of buoyancy which will want to bring him to the surface but we can pretend for a while. SECOND: Adam could possibly cut the valve stem to allow the air to excape and if he could form a tight seal with his lips, let the tire's air pressure (30 psi - depth pressure ~ 5 psi = +25 psi escaping) should be enough to expand his lungs without Adam haveing to "inhale". I'm sure Jamie can vouch for this seeing he is a diver. this is how the scuba regulators work. I believe this second option would be more difficult than the first to pull off due to difficulty sealing his lips on a small stem while underwater.
It looks to me like an ad hoc method isn't likely to work. Without a good seal and a means of regulating air flow, it's not going to work, period. OTOH it shouldn't be hard to fabricate an adapter that would allow a scuba regulator/mouthpiece to be hooked up to the tire's Schrader valve stem. One of those lever action devices used to inflate tires would be a first choice.
The question is whether or not there would be adequate air flow with the valve in-place, or even if it's removed. Regardless, it would have to be more James Bond than MacGyver.
About 30 years ago, the wife and I visited Weeki Wachee Springs in FL. They have Mermaids that use hoses to breathe under the water during the show. Some did not put the hoses in their mouth but used the exiting air to build up an air chamber in their mouths. I think this myth should be revisited a Weeki Wachee Springs. Jamie in a mermaid suit, attractive women, great underwater photography. (A number of shows and movies have been made there.) BTW, I am in now way connected with Weeki Wachee.
As a public safety diver and Dive Master (like Jamie), this is very possible. In Rescue dive class you learn to breathe off of a free flowing regulator. To get the volume of air that is needed one has to cut off the tip of valve stem. Then cup or wrap a hand around the valve stem to channel the air into your mouth. For something fun to try, members of our dive team have done it.
Question is; will someone have the frame of mind to complete all the steps required. Throw in zero ‘viz’ (after the car hits the bottom and stirs up the sediment) I would guess even a diver will have trouble doing this.
I have to disagree with your findings in the episode in which you tried to breathe under water using the air from the tire of a car. I have been able to stay under water for well over 2 and a half minutes breathing the air coming from the bottom of a hot tub. The trick is to seal your lips so that no water gets in your mouth. Much like you would a straw. This myth should not be busted.
I don't think there should be any special circumstances involved, like attaching a regulator or tire pump hose to the valve stem as others have suggested.
The myth is supposed to be about being forced into a lake by the bad guys and having to stay submerged by breathing tire air. It would be unlikely that you would have time to setup anything too fancy.
I think they made a mistake by letting the tire air flow freely out of the valve (and later out of the knife hole in the tire). They should have left the valve intact and given Adam the valve stem cap to hold in his teeth. Most valve caps (but not all) are designed to let you release air from the tire by pressing the top of the cap into the valve. By holding the cap in his teeth (maybe along the side molars, the incisors might hurt too much unless he held the cap against the front of the incisors, using the teeth to push the cap into the valve), he might be able to put his mouth over the stem and regulate the air flow this way. A complete seal over the stem may not be necessary in this case, I'm not sure.
Of course, a pen or a fingernail might work as well (like Mr. Bond), the point being that he could regulate the air flow, making it easier to breath this way (like others have suggested).
I also think that he should hold his nose closed while doing this. It would be one less thing to coordinate while trying to breath this way underwater. Also, a quick series of short breaths (breath in then out, spitting out water on the "out" breath) might be better than trying to inhale one big gulp of air.
A revisit of this would be easy since they only need to submerge Adam and the tire, unlike the original filming of this during the "Submerged Car Escape" episode.
Later!
ps. Since it's worth repeating, next time you choose to air footage that "didn't make it" on a previous show, just say so. Don't pretend that you've just done it. I think it damages your crediblity (as if the Discovery Channel producers/representatives haven't been doing that enough lately.).
This message has been edited. Last edited by: majmattmason,
As a public safety diver and Dive Master (like Jamie), this is very possible. In Rescue dive class you learn to breathe off of a free flowing regulator. To get the volume of air that is needed one has to cut off the tip of valve stem. Then cup or wrap a hand around the valve stem to channel the air into your mouth. For something fun to try, members of our dive team have done it.
How do you propose cutting off the tip of the valve stem? They're made of brass, and would require tools to cut them. I suppose that heavy duty wire cutters might do the job, but they would also crush the valve stem, effectively cutting off the air flow. A small hacksaw might work, but the exertions of sawing through the valve stem would quickly exhaust whatever oxygen you have in your lungs. It should go without saying that if someone comes prepared with specialized power tools for the job, they might as well just bring scuba gear instead.
After going to all of this effort, what have you accomplished? You've made an already short valve stem shorter. You've removed the pintle from the Schrader valve, leaving you with no way to open the valve. In fact, you may end up with a valve that's stuck closed. It looks to me like your plan would leave you in worse shape!
Why do you think that it's so important to shorten the valve stem in the first place?
IMO, joosep-georg has the most plausible solution.
At first I thought that using such a device would require pre-planning. Obviously anything that requires pre-planning means that you can pre-plan a better solution, making the need to use the air from your car's tires moot. However it occurred to me that the electric tire pump that I keep in the trunk of my own car is accessible from the passenger compartment, through fold-down back seats. Even cars without this feature can have their rear seats removed fairly easily IME. So it's at least plausible, provided that you're pre-prepared with more car care tools than most people carry. I suppose that someone who enters into situations where he or she gets shot at may well be prepared for more mundane problems.
I always carry a pocketknife, and could easily cut the hose loose from the pump. In an emergency, I could probably find a way to tear it loose if necessary. The fabric-covered hose provides a good grip for handling, and good sealing. The toggle mechanism that simultaneously holds the attachment fast and opens the Schrader valve makes for quick and easy deployment, and can be used to regulate air flow if necessary. It might be possible to just bite down on the hose for regulation.
I'd like to see that tested. Doing it with just a tire, a pre-cut hose and enough weight to keep the tire and Adam submerged would be a good proof of concept.
I don't think there should be any special circumstances involved, like attaching a regulator or tire pump hose to the valve stem as others have suggested.
Well yes, of course. That was my point, after all.
I've been following mythbusters since way back when and finally i decided to comment...
You had trouble breathing in the air because the water you took in settled in the back of your throat....
[Try holding the tire flipping yourself upside-down then the water will pool in the roof of your mouth allowing you to breathe the air... just make sure you breathe very slow... Also after each breath press the water out of you mouth with your tounge since it will collect constantly]
Even though it was not the original myth I like the idea of something catching the air as it comes up and then breathe the captured air. This hides the air bubbles reaching the surface and allows breathing. I do have a question about the James Bond movie "A View to a Kill". If the water was clear enough for Bond to see the villians wouldn't it be clear enough for them to see him or at least his movements?
I knew someone would bring up airbags. You cannot use airbags for breathing underwater for a very simple reason. They should be called chemical fume bags. the chemical used to inflate airbags is sodium azide, which produces toxic fumes which you sure would not want to breathe. In addition, the airbag deflates almost as fast as it inflates. If you watch the segment where they were trying to see if the thumbs would be ripped off, you can see the holes in the airbags that bleed off the pressure. I have seen in movies where someone had an airbag inflate, then he had to cut it away. they don't work like that, the inflate, then deflate once the impact has happened. After the impact, they are useless, and could actually impede rescue efforts so they are designed to collapse immediately.
This one obviously demands a revisit. I agree with most of the previous posts and suggestions regarding the underwater breathing but what really got me is that in this movie myth the people attempting to breathe out of the tire are either intelligence agents (007, Sydney Bristow in Alias) or professional assassins (Jason Bourne). They are not regular people like Adam, who have never received any special type of training... what I'm saying is get one of those professional divers or swimmers who commented on this forum and let them attempt the stunt. This way I believe you'll find the myth confirmed.
There are a couple of things that make bladders (shirts, handkerchiefs, etc.) problematic. Most people with a lung full of air already float pretty well. Adding a bladder big enough to get two good breaths, approximately 5 liters times 2 would provide more than ten lbs of flotation. Unless you go in with a few rolls of quarters in your pockets the extra flotation will be another element to contend with. It does seem your hands would already be dealing with the air bladder and valve stem.
Although many have stated they have breathed air out of tires, doing so may not be preferable unless like Mr. Bond, we have people shooting at us when we surface. Jacuzzi air pumps present less danger as they aren’t capable of great static pressures nor do they affect the air stream. Commercial air pumps can run hot and may if they leak some oil, flash combust that oil (like a diesel) on the pressure stroke creating carbon monoxide. High pressure breathing air compressors typically have filter sets that cost five or ten times the cost of the compressor you’ll find at your auto mechanic’s. It most likely will not be a problem for short durations or limited depth as most of you have survived but should be kept in mind if any of you are going to try for a tire breathing record.
In any case, sealing the airflow can be a serious risk. One of the previous writers (stated he was a professional diver) specified a moderate over pressure and therefore flow rate. The the Weeki Wachee Springs mermaid's gear provide the same condition. Uncontrolled flow causing over pressures (in the lung) as low as 1 psi or 2 feet of assent can cause an embolism. While I’m not saying “OH MY GAWD, DON’T DO IT YOU’LL DIE!”. A little bit of caution is in order. Make a mistake and you can be seriously injured by sealing your mouth on an uncontrolled air flow source.
The idea behind the pure nitrogen tire fills was ostensibly that the fill lasts about three times longer as nitrogen permeates the rubber more slowly. Pep Boys offers the nitrogen fill as does Costco. Just as in the old days you’d find water rather than ethyl glycol in the radiator, today you may not find air in the tires either. By the way it costs $2 to $10 per tire.
This message has been edited. Last edited by: deltad2,
Why didn't they cut the tire stem and suck on it for air. They talked about a lack of proper seal while sucking on the sidewall, but that might have been achieved if they would have cut the stem.
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