Archive | September 2012

Why You Cannot Open Airplane Windows

Ann Romney’s plane made an emergency landing after the cabin filled with smoke. At a campaign stop in California, Mitt Romney had this to say about the incident:

“I appreciate the fact that she is on the ground, safe and sound. And I don’t think she knows just how worried some of us were. When you have a fire in an aircraft, there’s no place to go, exactly, there’s no… and you can’t find any oxygen from outside the aircraft to get in the aircraft, because the windows don’t open. I don’t know why they don’t do that. It’s a real problem.”

There does not appear to be a video available of this statement, so he may have just been joking. However, in case you were wondering, allowing the windows to open on any high-altitude aircraft is a bad idea.

Temperature

Small private planes fly at an altitude up to 12,000 ft. above sea level. The standard temperature at this altitude is 16.2F. That is frigid, and maintaining the internal temperature of the cabin would be impossible if someone could just crack a window. Commercial jet liners fly much higher than private planes, and the temperature outside drops to around -49F.

Pressure

Have you ever wondered why aircraft include oxygen masks? Any plane flying over 10,000 ft. must maintain cabin pressure to prevent physiological problems associated with the low pressure of oxygen and other gases. Cabin pressure is maintained by pumping compressed air into the aircraft cabin. If someone were able to open windows, it would be impossible to maintain appropriate air pressure.

What would happen to you if Mitt opened the window on your plane? First, you would experience slugging thinking, dimmed vision, and eventually, loss of consciousness and death. To combat the low partial pressure of oxygen in your lungs, you would begin to hyperventilate. The low pressure of nitrogen and several other gases would cause dissolved gases in your bloodstream to begin to bubble. This will make you tired, forgetful, and cause you to develop a headache, subcutaneous itching, and possibly even a stroke. As your plane changes altitude, the gases in your body will expand or contract causing pain in your middle ear, gastrointestinal tract, and even your teeth!

Explosive Decompression

Have you ever watched a movie where a bullet-hole or small opening causes seats, items, and people to be ripped out of the plane? That is not going to happen from lowering a window. It can happen with a large and sudden rupture, which is why faulty cargo doors cause plane accidents.

Opening a window on a plane in flight would cause rapid decompression. Your lungs would be at risk for damage, but no danger from human projectiles. Still, you will probably not survive long enough for the plane to land.

The bottom-line is this: having the ability to open windows is a bad, and deadly, idea.

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Step by Step Speciation

Escherichia coli

Researchers at Michigan State University have performed an experiment detailing the step-by-step speciation of E. coli bacteria to consume citrate in the presence of oxygen.

The results show that new functions come about in three stages (generalizing from the specific experiment):

  1. Potentiation – mutation causing trait is acquired in population
  2. Actualization – trait caused by mutation is or becomes advantageous
  3. Refinement – mutations that enhance the new advantageous traits are acquired and propagate

Their research includes the frozen generations of e. coli so the exact situation and populations can be repeated.One interesting detail is that the mutation that enabled the consumption of citrate isn’t typical. Two chunks of DNA were combined so that one chunk encoded the new protein and the other expressed it.

The discovery of the mutant happened back in 2003. Years later have yielded much data as Carl Zimmer explains in his blog.