#learningoftheday

Post#45                        Feb 25,  2020                 Tue 00:21 AM

Do you know, sometimes, flights dump fuel in air, known as fuel dumping. But why do they carry extra fuel if they don’t even need this? Isn’t this a pure wastage of money, as well as source of pollution?

Definitely it is. But it has its own reasons. But the reason is more of a necessity of time, than a lack of planning.

All planes are designed with a standard weight limitation. It has a take-off weight limit and landing weight limit. Landing weight limit is around 10,000 Kgs less than the takeoff weight limit.

Plane weight is measured at different stages.

Dry Operating Weight: Without fuel and passengers

Zero Fuel Weight: With passengers and luggage

TakeOff weight: Zero Fuel Weight + fuel weight

Landing weight: Takeoff weight - consumed fuel weight

Landing weight is normally within the limits, but may have exceptions, when plane has to make emergency landings for some reason.

Post#44                        Feb 24,  2020                 Mon 23:00 PM

Why all airplanes are painted white?

Painting an Airbus airplane needs 1100kgs of paint, and just printing the logo needs around 500kgs of paint. So, if no paint is used, the plane can carry 5 more passenger’s weight with same structure. 

So question is why does an airline company paints the airline, when it is increasing the operating cost.

Even the airline company used to think so earlier, and they didn’t use to paint their flights. But because of bad weather, and exposure of direct metal to atmosphere used to degrade the surface, which needed to be polished.

The polishing cost used to come higher than painting cost. So they started painting it white, after putting a green anti-corrosive paint.

Post#43                        Feb 23,  2020                 Sun 22:58 PM

The problem with rockets is that they are expensive, mostly single use and occasionally have been known to explode. That’s why for over a century scientists and sci-fi writers alike have dreamed of creating a space elevator to ferry astronauts and payloads between the Earth and low orbit. But is this even possible? Can a building be so high that it can take people to space?

So yes, it is. Astrophysicists says it can be true. But what material can be so strong to handle so much of weight and pressure? Answer is: Carbon NanoTubes. Carbon NanoTube is 100 times stronger than Steel, and as flexible as Plastic. The steel tether is too heavy to be used as a full-sized space elevator, which must, of course, extend for tens of thousands of miles

Just like a ball tied to a pole using a rope is kept by giving the ball a perpetual motion around the pole, the same way a counter-weight attached to carbon-nanotube ribbon on Earth, will be kept straight. The centrifugal force at the space end of the ribbon will help in balancing the gravitational force applied on the earth side.

The ribbon will be thin like a paper, and just few centi-meters wide.

The space elevators are planned to be built around equators, where hurricanes and tornadoes are scarce. Also, it needs to be planned to keep it safe from terrorist attack as well.

The elevator would go as high as lower earth orbit, or geo-stationary orbit, where satellites can sync the position for transportation for cargo or men.

A space elevator would create a permanent Earth-to-space connection that would never close. While it wouldn't make the trip to space faster, it would make trips to space more frequent and would open up space to a new era of development. It would significantly lower the cost of putting cargo into space. Although slower than the chemically propelled space shuttle, the lifters reduce launch costs from $10,000 to $20,000 per pound, to approximately $400 per pound.

Japan’s Obayashi Corporation, is already doing lots of research in this, and have designed a prototype for this. 

Post#42                        Feb 22,  2020                 Sat 16:34 PM

Have you noticed flights have two different coloured lights on its two wings: Red and Green?

Do you know the reason?

These are called Position/Navigation Lights.

Red is always on the left wing tip, green on the right, each beaming two rays at 110 degrees.

These lights are used to reduce the collision, mostly during night time. At night time, the flight is not clearly visible, except the colourful light, which indicates, which direction flight is going, whether it is coming towards, or have crossed you.