2011-02-20 10:05:12B-52s proove that global warming is a lie!
John Hartz
John Hartz
john.hartz@hotmail...
98.122.68.19

The following was posted today on a comment thread to the article, "EPA fight heads to the Senate" posted on Politico.com. Has anyone ever seen this claim before?   

Airplanes get lift from the air.  Warm air is less dense, and gives less lift.

If "global warming" were happening, the air would be less dense, give less lift, and this would mean that large, heavy airplanes would not be able to take off unless the gross weight were reduced.

The B-52 is a large, heavy airplane, and there have been B-52s in the air every day since the plane was put in service in 1955.  

The last one was built in 1962.  That means that the newest B-52 has been flying for nearly 50 years, with tens of thousands of hours of flight time.

If "global warming" were true, the B-52 "all-up" takeoff weight would have had to be reduced, to adjust for the reduced density of warmer air.  This has not happened.

With a 488,000-pound gross takeoff weight, an increase in temperatures of ONE PERCENT would reduce the takeoff weight capability by MORE THAN TWO TONS.

According to the Warmers' "Hockey Stick Chart," the temperature has gone up one degree (Fahrenheit) since 1960 -- an increase of nearly two percent during the time that the B-52 has been flying.  This would mean a reduction in gross takeoff weight of 9,600 POUNDS.  That would mean cutting payload, fuel load, or a compromise between them

The B-52 has a payload of 80,000 pounds.  It would be impossible to hide or ignore a loss of  1/8 of gross weight capability -- the equivalent of one cup out of every gallon of milk, or 12 of the keys on your computer keyboard.

There has been NO TEMPERATURE-RELATED LOAD REDUCTION DURING THE FIFTY-SIX YEARS THAT THE B-52 HAS BEEN FLYING.  Not five tons, not five pounds, not five grams.

That's not tree rings, hockey charts, superstition, conjecture or suggestion.  That is cold, hard mathematics.

Global Warming ain't happening, folks.


2011-02-20 16:18:11
Daniel Bailey
Daniel Bailey
yooper49855@hotmail...
97.83.150.102

I can disprove that.

 

It was the construction of the Spruce Goose in 1947 that brought an end to the 1940's decline in global temperatures.  The Spruce Goose was maintained in operational readiness until Howard Hughes' death in 1976.  Global temps over that period?  Flat:

 

Since then combined temps have resumed their inexorable rise:

 

 

Add-in particulates and aerosols from the war as the causative factor of the 1940's temperature decline (similar to the drop during WWI) & it's all covered:  every base.

 

Heh.

2011-02-20 21:15:31
Paul D

chillcast@googlemail...
82.18.130.183

Alternatively, if it were warmer, the take off speed would have to be greater, requiring more fuel rather than a reduction in pay load.
You could check to see if longer take off runs and more fuel were required. Reducing payload isn't the only solution, the UK developed a simple ramp to get Harrier jump jets to carry greater loads on a short take off run. So the 'reduce payload' meme would seem to be another cherry picking moment.

NASA have an educational airfoil sim that looks like it can vary air density and temperature:

http://www.grc.nasa.gov/WWW/k-12/problems/Dalette/LiftvsAirspeed_int.htm

Some info:

http://www.pilotfriend.com/training/flight_training/aft_perf.htm

"As a result, the take-off distance is substantially increased, climb performance is substantially reduced and may, in extreme situations, be non-existent."

But another point is that engine efficiency has increased, so that might mask any change in reduced performance due to changes in the air.

There are numerous other reasons why this is crazy, I'm sure the scientifically literate can say why there are other flaws. One obvious one is that warming is not evenly distributed across the Earth. We know the polar regions are warming faster. I would think that the heat island effect of runways and airports is far greater locally than the effect of climate change.

 

From wikipedia (http://en.wikipedia.org/wiki/Runway):

An aircraft will need a longer runway at a higher altitude due to decreased density of air at higher altitudes, which reduces lift and engine power. An aircraft will also require a longer runway in hotter or more humid conditions (see density altitude). Most commercial aircraft carry manufacturer's tables showing the adjustments required for a given temperature.


2011-02-20 21:30:12
Paul D

chillcast@googlemail...
82.18.130.183

 

Here you go Badger, Christian Science Monitor has covered it:

http://www.csmonitor.com/Environment/Bright-Green/2009/0910/a-warmer-world-could-make-current-airport-runways-too-short

Apparently some flights are cancelled on hot summers (see page 2 of the report). So increased frequency of would increase flight cancellations, unless airport runways are increased in length.


The B52 nerd needs to get a life!

2011-02-20 22:09:35
MarkR
Mark Richardson
m.t.richardson2@gmail...
134.225.187.80

1 degree Fahrenheit isn't a 2% increase or 2% change in density. The guy's a scientific illiterate.

 

To use the gas equations you have to use an absolute temperature scale, like Kelvin. If you plug Fahrenheit into an equation like PV=nRT you're on a fast track to flunking your school science class.

Say temperatures have risen something like 0.6 C since the '60s. The absolute temperature in the '60s was about 288 Kelvin on average. A 0.6 K rise is an increase of 0.2%, not 2%.

B-52s are not run exactly at tolerance either. And I'd be surprised if we're still using exactly the same engine and there has been a 0% improvement in its thrust (which would increase acceleration and ultimately lift).

 

Interestingly, the properties of gases give us more ways to detect changing climate. The troposphere has expanded and the stratosphere has shrunk, supporting the measurements of tropospheric warming and stratospheric cooling. The tropospheric expansion shows that warming is happening, and the stratospheric shrinkage shows a combination of ozone loss there and increased greenhouse effect in the troposphere, giving us a very important 'fingerprint' of human caused global warming.

2011-02-20 23:35:01
MarkR
Mark Richardson
m.t.richardson2@gmail...
134.225.187.80

Also, the lift equation:

http://www.grc.nasa.gov/WWW/K-12/airplane/lifteq.html

 

So from the ideal gas law PV=nRT => ρ is proportional to 1/T at constant pressure. So if T increases by 0.2%, density decreases by roughly 0.2%. To offset this, you need to increase take-off velocity by about 0.1% (because of the velocity squared dependence of lift).

 

Since B-52s work in the desert and over ice fields, they're clearly not working exactly at tolerance. Basically the guy's a typical internet climate 'skeptic'. Thinks he's worked out something really clever and everyone else must therefore be wrong, but he's gone wayyyy off the mark.

2011-02-21 01:36:08Muchos gracias
John Hartz
John Hartz
john.hartz@hotmail...
98.122.68.19

Thank you all for your feedbackand useful information/links. 

MarkR posted a direct response to the blogger on the comment thread. He has yet to respond to MarkR.

It will be interesting to see if this meme speads throughout Climate Denier Land and shows up elsewhere.   

2011-02-21 23:43:31
Dikran Marsupial
Gavin Cawley
gcc@cmp.uea.ac...
139.222.14.107

 

I don't think I would want to fly if planes were so marginal that a difference of a bit less than one degree C made a difference as to whether it would fly or not! (although the Spruce Goose mentioned in an earlier would come close ;o)

2011-02-22 11:23:39
Rob Honeycutt

robhon@mac...
98.207.62.223

That has to be the stupidest thing I think I've read in quite a while.  Any licensed pilot can refute that.

The broad concept is correct.  In aviation it's called density altitude.  Density altitude is pressure altitude (altitude measured at standard barometric pressure) adjusted for non-standard temperature.  So, a hotter location, say an airport in the desert, effectively has a higher altitude relative to the performance of an aircraft that an airport at a cooler location.  

Since a high desert location in the summer can have a temperature difference of 34C over standard temperature (15C), and B52's certainly land at high desert military bases, the 0.8C attributable to to CC is not a factor.

Interestingly though, this could eventually become an issue as climate change pushes temperature extremes higher.  A fully laden B52 at a high altitude airport on an extremely hot day could very well have problems taking off.  Even small aircraft run into this problem sometimes.  I've taken off from high hot airports and it's amazing how much more runway you need. 

2011-02-22 11:29:22
Rob Honeycutt

robhon@mac...
98.207.62.223

I also just read the last part of that as well.  //facepalm

Of course there are no adjustments to the performance specs...  because they are relative to temperature.  You make the calculations based on the temperature of the airport at take off, not based on the temperature of the planet.