World Airports Voronoi

Online visualization by Jason Davies presents the world organized as territories in relation to the distance between airports:

Each region is closer to a particular airport than any other. This partitioning of the sphere is called a spherical Voronoi diagram, and was calculated by d3.geo.voronoi, which is currently underdevelopment.

More Here

The Physics of the ‘Stall’

The proposition that more the angle of attack, more the lift does not hold at all angles.

At about 14 degrees, something weird happens and the aircraft instead of soaring the skies starts to plummet to the ground.

When this happens it is known as a stall.


What causes Lift ?

The main thing to know is that a difference in pressure across the wing–low pressure over the top and higher pressure below–creates the net upward force we call lift.

Upon reaching a certain velocity, the aircraft’s lift is more than its weight and as a result, the aircraft takes off .

The Concept of a Boundary Layer (BL)

There is a high chance that you might have heard this word even in a casual conversation about wings and that’s because its an important concept in the context of aerodynamics and associated fields.

To understand the physics of a stall, lets consider the interaction of a moving air on a flat plate.

The nature of airflow over a wing/plate is the result of stickiness or viscosity of air. 

The first layer sticks to the wing/plate not moving at all.

The second layer in frictional contact with the first moves slowly over it.

And the third layer moves somewhat faster than the second

Thus layer by later the flow builds up to the free stream velocity or airspeed. These layers of flow are known as boundary layers.

What happens to the BL during a stall?

                                              Source Video

During a stall, these successive tiers of air that form the boundary layer lose their gripping on the surface and break away into turbulence.

( what i mean by turbulence is the chaotic wiggling of the test leads attached to the wing in the animation )


It takes a pressure difference between the top and bottom parts of the wing in order to produce lift. But when the flow of air becomes turbulent ( i.e during a stall ), this pressure difference is no longer established.

As a result of which, the lift drastically decreases and the aircraft starts dropping to the ground.

How to get out of a stall ?

Stalls can cause problems only when the pilot is not aware that the aircraft is stalling. ( Unlikely but has caused accidents in yester times )


As the airplane loses altitude, its nose dips down and airspeed picks up quickly. This restores the lift and the pilot would be able to regain control and bring the aero-plane into level flight.

How are stalls detected ?

On light aircraft there is a reed (much like used on a musical wind instrument) mounted on one wing root, which is angled such that at the Angle of Attack which would cause a stall, the reed “plays” which can be heard in the cockpit.

Here is a view of where this system is mounted on a Cessna

On some aircrafts, it is a similar principal, however instead of a reed, it uses a fin which at critical AoA pushes a micro-switch which activates a buzzer/horn inside the cockpit.

Here is the assembly on a Beech 18

Large commercial aircraft typically rely on either Angle of Attack (AoA) Vanes or Differential Pitot Tubes  to supply input to flight computers for the purpose of calculating AoA.



A lot of important stuff regarding aerodynamics in this post. Here’s a summary of the post:

Boundary Layer concept  — >  Why do aircrafts stall ? — >  How to get out of one  — > How are stalls detected ?

That’s all folks!

Hope you enjoyed today’s post and learnt something new.

Have a good one !

Avoid people who mess with your head. Avoid people who intentionally and repeatedly do and say things that they know upset you. Avoid people who expect you to prioritize them but refuse to prioritize you. Avoid people who can’t and won’t apologize sincerely. Avoid. Avoid.
—  Unknown

I really can’t stress enough how important it is to talk to your friends, family members, and partners regularly about their right to set boundaries, even ones that inconvenience you.

We absolutely live in a hierarchial abuse culture where people can and do impose their will on each other in a million tiny ways. A lot of people just expect it - they’ll make choices according to the assumption that you, too, are invested in controlling them to whatever degree - because unless you consciously make a point not to be, it’s possible that you are.

In a healthy relationship people ask for consent often - “Do you want to do this? Are you comfortable with this? Is there anything you think we should change about this plan?” And then, they clarify that negative answers are totally normal and okay.

Checking in can sound like, “Hey, you know I love doing X but if you ever don’t want to you know that’s okay, right?” It’s paying attention to nonverbal cues that someone is uncomfortable and giving them an out - “You don’t seem excited about this party, I want you to know it totally won’t be a big deal if you’d rather not.”

In a healthy relationship there’s a huge difference between “I said no” and “you shouldn’t have asked”. “No” is normal and expected and it’s assumed that sometimes it will be the response. There’s an intentional effort not to punish each other for not always giving each other what you want.

Normalize “no” in all your relationships. Seek it out! Give people extra opportunities to say no! And accept it. Recognise that it’s a good sign when your loved ones feel safe enough to not agree to things they don’t want out of fear of your reaction.

Just - check in. I don’t care what kind of relationship it is, don’t assume people know it’s safe to say no to you unless you remind them and show them regularly. Making space for healthy boundaries is one of the most important things to communicate with the people that you care about.

E naquela madrugada ela voltou a ser a garotinha de 10 anos que se esconde chorando embaixo das cobertas com o intuito de se proteger dos monstros imaginários, mas dessas vez ela não conseguiu se proteger dos monstros, pois o único mostro existente naquele quarto era ela mesma, com suas inseguranças e pensamentos grotescos.
—  Samira Melo