Skip to main content

Can Global warming really ground planes?

On the 20th of June 2017, American Airlines cancelled more than 50 flights to and out of the Sky Harbor International Airport in Phoenix, Arizona. The primary reason for this cancellation was that the temperature of the region was too high for planes to fly.

Dr. Marshall Shepherd, an internationally known weather expert and the host of Weather Geeks, wrote a  post on Forbes explaining the phenomenon behind flight cancellations and high temperatures, which was then tweeted by Elon Musk, where it went viral.

To summarize Dr. Shepherd's article and explain why flights were cancelled, we first need to understand the principle of flight in an aeroplane. The wing of the aeroplane is designed to create a difference in the momentum in the air ahead of the wing as it passes over it to create lift. Faster the change in the momentum greater is the lift created, which allows the plane to take off.

True Airflow over a wing with lift
True Airflow over a wing with lift

As the temperature of the surroundings (at the runway) increases, pressure of the air under the wing decreases. This means that the aeroplane now needs to change the momentum of the air much faster than earlier to create the necessary lift or reduce its gross weight to achieve the same lift in the same distance. While this is possible in some scenarios, in certain others, it is not and that is exactly what happened to the American Airlines flights, which were all being operated using the same kind of aircraft, the Bombardier CRJ.

An aviation enthusiast myself, I dug a little deeper to know what was so unique to these CRJ aircrafts that made them incapable of flying as claimed by this tweet from Verge. 

Well, it is not that planes cannot fly at higher temperatures. The Bombardier CRJ, manufactured in Canada, is basically a small plane aimed to be used for short distance flights and has operational performance records for temperatures only up to ISA + 15 degrees celsius  i.e. 48 degree Celsius or 118 degree Fahrenheit, temperature of Arizona on the day. The reason it was grounded is purely because of safety concerns since the manufacturer had not tested the aircraft in higher temperatures and is unlikely to do so, because it is no longer in production. 

Bombardier CRJ aircraft
Image credit: Bombardier

On the other hand, other commercial aircraft makers such as Airbus, Boeing have higher limits to their performance testing and have performance data for temperatures up to 53 degrees Celsius and were not affected by the temperature at the airport.

This is also evident from flight operations in the Middle East, the hub of famous airlines like Emirates, Etihad, Qatar, Gulf Air etc. which are busy during the nights and deserted in the afternoons to avoid such cancellations due to high temperatures. It is likely that given the increasing temperatures in cities around the globe, such cancellations will become more rampant in the coming years.

This is not the first incident of flight cancellations in Phoenix. In 2013, 18 US Airways flights were cancelled due to higher temperatures and the trend in Phoenix is to to break its own highest temperature record every year. 
So, we can expect Phoenix to announce more cancellations next year, the year after and so on, till we just accept it to be the new normal. 

But why should I single out Phoenix for this. All major cities in the world have recorded temperatures in the higher 40 degrees in the past few years and with rising global temperatures, they will soon reach the upper limits for flight operations in their respective zones and announce such cancellations during summers. 

Of course, the human civilization is not going to take this lying down. We will do everything we can to ensure that we continue flying as per our convenience. So, this would be mean a lot of research will go into funding research (more jobs created, hurray!) for discovering new materials to build aircraft that can withstand extreme temperatures, research into building more powerful engines that can create the necessary lifts faster and even better fuels that can generate more power out of the engines. 

It would also mean that we would probably work out a few compromises such as travelling earlier or later in the day or expanding the runways of our airports in the name of development and expansion or reducing the carrying capacity of the current flights and increasing airfares for the common man. 

But that is very little sacrifice that we will readily make to ensure that the rich and powerful decision makers of the world can go about denying climate change and any of its many effects on the planet, back out of promises that countries have made and raze forests to build power plants! 

Edit: Changes made to how lift is created by an aeroplane after feedback from Subbarao Raikar, an ardent reader and patreon of our blog. 


Popular posts from this blog

Do free energy magnetic motors really work?

The internet is rife with websites that promote generators that are capable of providing electricity without using any fuel. Built largely with magnets, these 'free energy generators' promise to cut your electricity bills and provide a much greener alternative to the electricity that is largely generated out of fossil fuels. Elaborate videos that give you estimates of how much money you can save without revealing any details of how to go about it, manage to keep the audience hooked on for a while, but $40 price tag, the loads of freebies and the instant $10 discount for not leaving the page, make the product and its seller highly suspicious. So, we decided to find out if these free energy magnetic motors really work?

The Principle

The magnetic motor works on the simple principle that we all already know, 'Like poles repel each other while opposite poles attract each other'. By arranging the magnets in a fashion where only like poles face each other, one can simply set t…

Why Sci-Hub’s story is so crucial to science?

On the 28th of October 2015, Judge Robert Sweet in his ruling at the New York district court declared that the website be blocked with immediate effect and managed to stop hundreds and thousands of researchers and science enthusiasts from accessing the holy grail of today’s science, the research paper.
What should be a simple means to communicate to the world one’s research findings, has become a currency of some sort. A ticket to a researcher’s professional success, a magnet for an investigator to attract funding for his lab and the elusive piece of the puzzle that the publishing group can hold you ransom for, until you cough up some good cash ($30 or above for a single article and thousands of dollars for a bundled annual subscription)
What Judge Sweet termed as a “disservice (to) public interest”, is actually a small website that allows you access to scientific research, old and new, and for free. Sci- Hub. Org, started in 2011, as a trusted place to access research …

Generating electricity from flapping tree leaves

As kids, you might have spent many afternoons, under a huge tree, enjoying its shade. In a tropical country like India, trees are a welcome sight in the month of May, when the sun is blazing in the sky and the shade offered by them is a hundred thousand times better than artificial cooling of the air conditioning units. But never in our dream would we have thought that the rustling of the tiny leaves of the trees could one day make electricity for us.Because that requires a Hendersonian moment! (just in a bit)

This brilliant idea has come from the lab of a biophysicist at Iowa State University, Dr. Michael McCloskey, whose work at the University largely involves the study of membrane transport in algae and adult born neurons but also has a background in plant sciences. It was his colleague in the department of genetics, Dr. Eric Henderson who first came up with this plan of harvesting energy from leaves as he wondered how much kinetic energy was being generated when winds blow across l…

5 things driverless cars will do to change our future?

The race for building the world’s first commercially available driverless car is on. Google seems to be leading the pack and in its own charismatic style has been very open about it. Elon Musk’s Tesla is considered the second best with their cars having almost automated the driving process. Tech favourites, Apple also seem to be in the race but everything is under wraps, as of now, and there is not even a hint of what Apple is planning to make, the car, the software or simply make the car accessible with your Apple ID.
Once part of science fiction, driverless cars will soon be a part of our lives and with major automobile manufacturers such as General Motors, Toyota, Ford investing in the technology, prototypes of driverless cars will soon be seen on the roads. Before we get there, a quick review.
The Driverless car
The concept of automated driving has been around for close to a century but progress was slow due to unavailability of technology. For a car to be autonomous, it needs to kno…

Solar cells that work in rain

In case you have read my last month’s guest post about harvesting solar energy in rust, you would be delighted to know that there has been yet another breakthrough in our attempt to harness solar energy.  For many years, solar energy has been targeted for being unavailable at night and during rains. The problem of utilizing solar energy at night can be resolved with the help of metal oxide cells as elaborated in my above post (do read it, if you have not done so already). And now researchers at the Ocean University in China have addressed the second problem and developed solar cells that can actually use rain drops to generate electricity.
Published in the German journal Angewandte Chemie, the paper titled, A Solar Cell Triggered by Sun and Rain, opens a new realm of possibilities when harnessing solar energy. Coating the solar cell with a thin film of graphene allows the cell to function even when it is raining. Graphene is nothing but reduced form of graphite that consists of a hone…