I put Nitrogen in my tires.

<div class='quotetop'>QUOTE(TJandGENESIS @ Dec 20 2006, 01:16 AM) [snapback]364493[/snapback]</div>

Most reasonable explanation I've seen: http://nslog.com/2006/01/09/better_gas_mil..._with_nitrogen/

At least two of the three reasons he lists don't apply to automobiles. I'd argue that the third one doesn't apply either. Due to the temperature extremes that an airliner tire experiences, the presence of moisture is going to have a much larger effect than it would on a car. So IMHO none of the three reasons he lists for airliners using nitrogen apply to automobiles.

 

<div class='quotetop'>QUOTE(staze @ Nov 12 2006, 05:01 PM) [snapback]347906[/snapback]</div>

Does the relative N vs. O molecule size remain the same at elevated pressures, like say 40 psi or 3.7 atm vs. 1 atm ? Intuition would tell me that lower "electron cloud force" might mean that gas would be more compressible, but then I'm just guessing.

 

<div class='quotetop'>QUOTE(Mr07Touring @ Dec 20 2006, 11:41 AM) [snapback]364623[/snapback]</div>

Yes, unless you're planning on touring a Neutron Star on your next vacation

 

I'd humbly suggest a switch to concrete tires and rubber roads.

While the unsprung weight of our wheel/tire combos would be a bit more than we're used to, in this scenario the folks who take care of the roads can now be tasked with worrying about whether they're aired-up with nitrogen 78% or something higher...

 

<div class='quotetop'>QUOTE(TJandGENESIS @ Nov 12 2006, 01:51 AM) [snapback]347741[/snapback]</div>

I guess this is going to be a rant.

Fractional distillation of air to produce "pure" nitrogen takes quite a lot of energy - you're certainly not being green by creating a market for what is ostensibly energy-intensive air. This quickly leads to the bottled water argument...

O2 may (or may not) oxidize the inside of tire, although chances are slim it would make any detectable difference in the lifetime of your tire anyway.

O2 does permeate tire walls, slowly. You'd better be checking your tire pressure more frequently than that anyway!

Valve stems can be contaminated by *anything*. Good grief.

Compressed air does contain water - unless you have a drier inline (I do but more for pump oil). Does it matter? I can't even count the number of tires I've bought in my life and I inspect them scrupulously. I've never seen condensate in the tire or any evidence of such, although I'm there are certainly tiny amounts depending on tire temperature.

Saving fuel? Better handling? *just* as a result of having N2 only in your tire? No.

Find *one* lick of evidence that indicates or even suggests that O2 lead to a tire failure.

And for god's sake, that URL you posted stated that "the FAA requires it" as if this added some credibility. The FAA requires things that put money in the right pockets or avoids the emptying of the wrong pockets.
The FAA (via Congress) allowed airlines to monitor their own security (to increase airline profit) which is what allowed 9/11 to happen and the Iraq war to start. I think you'll agree, not a very cost-effective move there.

I hope people are not buying things just because they say "green" on them without putting some thought into it.

Why am I on a soapbox about this? People are dumping fantastic amounts of energy down the toilet to be "green" with N2 in their tires when it does not provide substantial (any?) benefit.

<div class='quotetop'>QUOTE(jbarnhart @ Nov 12 2006, 10:16 PM) [snapback]348053[/snapback]</div>

A mole of any gas is 22.4 liters at standard temp and pressure.

Readily derived from ideal gas law.

 

<div class='quotetop'>QUOTE(TJandGENESIS @ Dec, 01:32 AM) [snapback]367569[/snapback]</div>

How much better is your mileage using Nitrogen vs. standard dry air?

Rick
#4 2006

 

<div class='quotetop'>QUOTE(TJandGENESIS @ Dec 28 2006, 03:30 PM) [snapback]367772[/snapback]</div>

Those are double digit percentage mileage increases with the nitrogen vs. air in the tires. That is an increase that cannot be ignored. It also represents a significant amount of energy that somehow must have been dissipated by the air only tires. Where did it go?

It just seems too good to be true. If so Toyota, and all other auto manufacturers for that matter, could instantly raise their CAFE standards to unheard of numbers with the simple and cheap addition of nitrogen filled tires only.

I currently have a true lifetime (about one year of ownership) 49.5 MPG average with standard air fill (44/42). My driving is mostly highway at 70 to 75 MPH and some back roads at 60 or so with the A/C on all the time. So with putting nitrogen in my tires I could get from the mid to high 50's in MPG? Hmmm....

Rick
#4 2006

 

<div class='quotetop'>QUOTE(TJandGENESIS @ Dec 28 2006, 03:30 PM) [snapback]367772[/snapback]</div>

What was the cold tire pressure when you were using air and what is the cold tire pressure now with the nitrogen? Did you change tires? I'll believe your statement if the only change is the gas in tires.

 

<div class='quotetop'>QUOTE(TJandGENESIS @ Dec 28 2006, 10:01 PM) [snapback]367982[/snapback]</div>

King Toyota thinks of it as pure profit. Costco gives you nitrogen for free, as well as free rotations and computer balancing, for the life of the tires when you purchase your tires there.

 

<div class='quotetop'>QUOTE(Display Name @ Dec 28 2006, 12:01 AM) [snapback]367529[/snapback]</div>

I'll chime in one this one. Usually the FAA regulates certain maintenance practices because they are tried-and-true ways of doing things learned the hard way from earlier aviators. Changes to maintenance practices usually come from recommendations from the NTSB following aircraft accidents.

One example: In March of 1986, an Aeromexico B-727 had a brake failure on takeoff. The brake failure caused the brake assembly to heat up and transfer that heat to the wheel/tire upon landing gear retraction. At FL310, the heat and subsequent expansion of the gasses in the tire caused an explosion that severed fuel and hydraulic lines near the wheel well. A fire followed the explosion and 166 passengers and crew were killed.

The accident investigation concluded that the tire had been serviced with air and that the oxygen content in the air had contributed to the fire that erupted in the wheel well. Several tests showed that a nitrogen filled tire most likely would have suppresed any fire.

Following the NTSB's recommendations, the FAA published an Airworthiness Directive (AD 87-08-09) that mandated the use of nitrogen in transport category aircraft tires. AD's are regulatory in nature and mandate the way certain maintenance must be performed. Failure to do so would result in fines and certificate action against air carriers.

In addition, AC 20-97B is an Advisiory Circular (recommended but not mandatory) published by the FAA that recommends the use of nitrogen to ensure a 5% or less Oxygen content for all aircraft tires-not just large transport category airliners.

This to me seems to be an example of the FAA following a rational recommendation from the NTSB that could potentionally save lives, and not merely "put money in the right pockets..."

Anyway, nitrogen in automobile tires seems like overkill in regards to fire suppression. The only real advantage might be gained from its low water content and subsequent protection against corrosion.


<div class='quotetop'>QUOTE(Display Name @ Dec 28 2006, 12:01 AM) [snapback]367529[/snapback]</div>

Correct me if I'm wrong here, but prior to 2001, FEDERAL regulations allowed knives onto aircraft; along with lighters, water bottles and shampoo in amounts exceeding 3 oz. The terrorists hell-bent on killing Americans were in possesion of APPROVED carry-ons.

What difference would it have made who employed the screeners back then? Hindsight is always 20/20!

 

<div class='quotetop'>QUOTE(Stepclimb @ Jan 1 2007, 02:17 PM) [snapback]369324[/snapback]</div>

Speak for yourself. I fly approaches at 220 knots in my Prius, and land at 180 knots. I need the N2 in my tires. :lol:

 

<div class='quotetop'>QUOTE(Stepclimb @ Jan 1 2007, 03:17 PM) [snapback]369324[/snapback]</div>

We're digressing from topic, but that happens...

Terrorists can still bring down a passenger jet pretty easily, I think we'll be seeing that again before too long.
Not to mention how easy it would be put 500 lbs of TNT and nails in a Cessna 172 and fly it into a football stadium. A TFR won't prevent that. To make it hard would be to make the airlines even less profitable than they were prior to 9/11.

Federal oversight was handed over to the airlines after deregulation, as I'm sure you know. The airlines adopted a set of security protocols at the behest of DOT, FAA, NTSB et al. The people who perpetrated the 9/11 attacks triggered twelve of the "red flag" security measures as I recall, and each one went unchecked or ignored. There had been increasing numbers of alerts regarding potential terrorist hijackings beginning in the late 80s. I can even remember a series of interviews with Brian Jenkins regarding such, and if I can remember it, surely the security officers in the airlines should.

Reinforced doors were suggested long ago to prevent this kind of scenario, but this was never required because it would be "too expensive." They pay jumbo pilots over a quarter million dollars a year, but a reinforced door is too expensive...

True enough, it doesn't matter who employed the screeners, but since the airlines employed the people (not just screeners) who blew the protocols a large number of times, the culpability is squarely on the shoulders of the airlines for allowing 9/11 to happen. There has been no accountability. The 9/11 commission concluded in the end there was a "failure of imagination." Pretty pathetic conclusion.

I read an interview with an FAA official who said something to the effect of "It hadn't happened before, so how could we have known?"

 

<div class='quotetop'>QUOTE(Display Name @ Jan 1 2007, 11:49 PM) [snapback]369359[/snapback]</div>

Perhaps, but I did address the Nitrogen issue as it applied to aircraft tires

<div class='quotetop'>QUOTE(Display Name @ Jan 1 2007, 11:49 PM) [snapback]369359[/snapback]</div>

I can speak to this as I am currently an airline captain. I beg to differ with you on this one. The reinforced doors we have now are a huge step towards stopping cockpit intruders. Many other procedures and protocols I can't address are in place today that would make a repeat of 9-11 highly unlikely to succeed. Are there still holes in the system? Yes, but a lot of time, money and effort are being put into place to fix the "holes"
The only real threat I can imagine that would be nearly impossible to curb would be that of portable, shoulder fired surface to air missiles (MANPAD SAM's). The only thing making this difficult is the ability to procure old soviet hardware that still works and then ship it to the US undetected. So I feel your "bring down a passenger jet pretty easily" statement is a little off the mark.

<div class='quotetop'>QUOTE(Display Name @ Jan 1 2007, 11:49 PM) [snapback]369359[/snapback]</div>

In addition to my airline flying, I am still an active "little airplane" GA pilot. Again, this statement is misguiding and only feeds into the irrational "fear" of general aviation (GA) aircraft. It's true you could overload a C-172 with 500lbs of TNT and nails and get it near a stadium. How many people would be injured? Maybe a couple hundred?
If massive damage was the goal, what would prevent a Ryder truck a-la Oklahoma city happening again? A TFR? It could certainly hold a lot more explosives than a small airplane and get a lot closer without drawing attention to itself.

Also, think about what kind of people would load up a plane like that? I don't know how much time you spend hanging around general aviation airports, but I've been hanging around them most of my adult life.
The kind of people that are involved in GA would tend to notice if a "new guy†showed up with a 172 and was seen loading it up with a lot of stuff. Check out www.aopa.org/airportwatch and or www.gaservingamerica.com There is a lot of good information there about what GA pilots are doing to prevent terrorists from using small aircraft. By the way, airline operations are usually exempt from TFR’s that affect GA. Operations into DCA and throughout the DC ADIZ for example don’t make airlines less profitable, it’s more of a function of passenger demand, fuel prices, capacity and a myriad of other factors.

<div class='quotetop'>QUOTE(Display Name @ Jan 1 2007, 11:49 PM) [snapback]369359[/snapback]</div>

First of all, de-regulation had nothing to do with security and everything to do with unfair competition and federal control of ROUTES and FARES.
In regards to hijackings, 9-11 was a MASSIVE paradigm shift. EVERY hijacking before 9-11 involved hijackers that were seeking asylum or wanted to get to a different destination or hold folks for ransom etc. Nobody wanted to weaponize the plane and commit mass murder-suicide. Again, you have the benefit of hindsight to say what should have been done.


<div class='quotetop'>QUOTE(Display Name @ Jan 1 2007, 11:49 PM) [snapback]369359[/snapback]</div>

The airlines?!?! How about the accountability of the Clinton administration for failure to nip ‘ol Osama and company in the bud after Trade Center ’93, Kenya, Tanzania, the Cole etc. Not much imagination needed there to figure out who was killing Americans and with the benefits of hindsight, we missed multiple opportunities to kill that guy and his buddies, but it seems he(Bill) could never make a command decision in a timely manner. To many distractions I suppose. Anyone remember how much our military and counter-terrorism and intelligence budgets shrunk during those 8 years?



<div class='quotetop'>QUOTE(Display Name @ Jan 1 2007, 11:49 PM) [snapback]369359[/snapback]</div>

I guess we should have predicted Pearl Harbor too? Anyway, it seems like both events were caused by shortfalls in intelligence gathering.

 

I just had new tires installed at Costco. They replace your black valve stem caps with green ones to signify your tires have nitrogen in them. I bet if you ask they will give you some green ones for free. Just change your black ones to green ones and save the $40.00.

 

<div class='quotetop'>QUOTE(Stepclimb @ Jan 15 2007, 10:11 PM) [snapback]376154[/snapback]</div>

I was with you until I got to reading this diatribe. Thanks for perpetuating the stereotype that airline pilots are right wing nuts.

Snopes - The Clinton administration failed to track down the perpetrators of several terrorist attacks against Americans - FALSE

 

<div class='quotetop'>QUOTE(IsrAmeriPrius @ Jan 16 2007, 06:13 PM) [snapback]376505[/snapback]</div>

I guess since were labeling each other, would it be fair or appropriate for me to call you a "left wing nut?"

I don't think so....You just happen to share a differing point of view.

Here are a few facts as I saw them during my time in the Air Force during those 8 years. You can dispute these as you see fit.

Clinton tended to handle all of the TERRORIST ATTACKS on American soil and those abroad that also killed and injured Americans as LEGAL matters. He felt for the most part that the courts should handle those that wished to do us harm. Of course, as we all know, the legal system is a rapid and highly effective way of going after terrorists.

The one time we did attack (with the cruise missiles), Clinton was "unavailable" to give the "go-ahead" when the situation presented itself. The command to proceed was not delegated as it should have been to the field commanders. Only later, when he was located, did he give the order to launch, but by then, the opportunity was gone and we missed. This rather "weak" show of force only served to bolster the spirits of our enemy.

To return to your original statement (the one where you called me a "nut"), I'll give you some background on why perhaps a few (not all) airline pilots might lean towards conservatism in some aspects. Like me, a good number of airline pilots were (and/or) are still in the military.

During the Clinton administration, we saw ourselves forced into a social experiment (Gays in the military*), and saw multiple small scale deployments to localized foreign conflicts where our presence was not strong enough to make a difference and the command decisions were taken away from the field commanders and handled at the White House by people with little or no military background. Additionally, the "vibe" of the White House senior staff was that they by and large loathed the men and women who wore the uniform of the United States.

I back up my point of view by inviting you to read a book written by a gentleman with whom I had the pleasure of flying the C-141. His name is Buzz Patterson and his book is entitled "Dereliction of Duty"
He observed first hand the way the Clinton White House handled military matters and the way they acted towards those military members who worked there. His primary duty while at the White House was to carry the nuclear launch codes and as such, required him at all times to be in close proximity of the President.




Footnote 1: I don't view myself as a conservative(“nut†or otherwise) nor a liberal, more of an open minded libertarian. I'm open to most any point of view if presented in a logical manner and backed up with verifiable facts.

*Footnote 2: I personally don't have any issues with homosexuality. Hell, most of our flight attendants are openly gay and are a pleasure to work with. That is an individual behavior that is protected by law. However, I do feel that openly suggestive homosexual behavior is incompatible with military service. Not because of how I feel about it, but because of how the rank and file soldier, sailor and airman feel about it. If they are distracted or made to feel uncomfortable in the performance of their duties, then that affects our nation's ability to defend itself.


Footnote 3: Nitrogen in automobile tires does not improve fuel economy. That is a function of tire pressure. In fact, separating Nitrogen from the atmosphere and pressurizing it requires much more energy (read: burning fossil fuels) than just using regular 'ol pressurized air.