Birds V-Fly !!! Mystery or Miracle?

Have you ever noticed the sky when flock birds migrate from one place to another?

Yes,of course? Had you ever think the reason for that.

There is a strong reason and mystery behind it.


Before getting that revealed let me define two technical words.

Upwash: The term upwash is used to refer to regions around an aircraft or airfoil where the air is moving in the opposite direction to downwash.The wingtip vortices induce an upwash outside the wingspan of an aircraft or airfoil balancing downwash produced by upper wing surfaces. Birds which migrate make use of this upwash and they form the V shape and make a easy fly.


Downwash: The meaning used most often by non-engineers, refers to the forcing of air downward during the creation of lift. This usage is most common with regard to helicopters where the effect is most dramatic.Now in terms of aerodynamics: The downwash immediately behind a wing is a consequence of the wing vortex system. This downwash is experienced by a horizontal tail placed in the flow behind a wing.

What Researchers Say?

The researchers found that there are 2 strong reasons behind this flying habit of birds. They are

1.The shape of the formation reduces the drag force that each bird experiences compared to if it were flying alone. the decrease in drag occurs thanks to the formation of wingtip vortices.2.The second strong reason holds for the V-Formation flying is that this orientation allows the birds to communicate more easily.

This V-formation provides the birds with good visual contact of each other to keep the flock together. This eye before communication minimizes the possibility of losing birds along the way as the formation crosses vast distances during migration.These kind of groups of birds will fly in a large V-shape with one bird in the lead and other birds trailing behind in two lines.A bird which is flying in one of these upwash regions gains free lift so that it can fly at a lower angle of attack.

Since the angle of attack is reduced, the induced drag is lowered so that the bird does not need to flap its wings so hard or as often to generate the thrust needed for forward flight. This obviously proves that bird’s muscle do not work harder. So its heart rate drops.


Yes, absolutely the bird does get not tired and can fly longer. 


Analysis proves: A flock of 25 birds in V-Formation can fly as much as 71% further than a single bird using the same amount of energy.


Do all Birds share drag force equally?

Because of spacing themselves apart in a proper distance, these birds can achieve optimum positions that reduce the drag of every bird in the V-Formation. But, not all birds benefit equally.

The first bird has to work the hardest since it flies into undisturbed air. The upwash this bird creates improves the aerodynamics of the two behind it, and these two further improve conditions for the next two birds in line.Although this kind of fly benefit all the birds, the bird which is in the lead position has to work harder. 




The time when the bird in lead position this bird tires, it will move out of the lead position and fall back into one of the lines of the “V”. To substitute this another bird from further back will rapidly move forward to take the leading position and maintain the V-Formation.The two birds in the trailing positions of V also tire more rapidly than those in the middle. 



The birds in trailing positions are also rotated frequently to share the tiredness throughout the flock.This kind of self management gives all birds in leading the flock and also they can relax by being in the middle of the flock.

Who taught them?

This V-Fly sense of teamwork comes by nature since the young birds in the flock realizes the ease of flying in the middle or V-Formation than flying alone.

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Lyrebird (Burung yang boleh tiru pelbagai bunyi)

Lyrebird ini boleh meniru dalam 20 jenis bunyi-bunyian yang dia dengar. Daripada bunyi burung lain hinggalah ke bunyi kamera dan alarm kereta. Menarik bukan ciptaan Allah SWT ini..




A Lyrebird is either of two species of ground-dwelling Australian birds, most notable for their superb ability to mimic natural and artificial sounds from their environment. Lyrebirds have unique plumes of neutral coloured tailfeathers.

Lyrebirds are among Australia's best-known native birds. As well as their extraordinary mimicking ability, lyrebirds are notable because of the striking beauty of the male bird's huge tail when it is fanned out in display; and also because of their courtship display. A group of Lyrebirds is called a musket.

A lyrebird's call is a rich mixture of its own song and any number of other sounds it has heard. The lyrebird's syrinx is the most complexly-muscled of the Passerines (songbirds), giving the lyrebird extraordinary ability, unmatched in vocal repertoire and mimicry.

Lyrebirds render with great fidelity the individual songs of other birds and the chatter of flocks of birds, and also mimic other animals, human noises, machinery of all kinds, explosions, and musical instruments. The lyrebird is capable of imitating almost any sound — from a mill whistle to a cross-cut saw, and, not uncommonly, sounds as diverse as chainsaws, car engines and car alarms, fire alarms, rifle-shots, camera shutters, dogs barking, crying babies, and even the human voice.

Lyrebirds are shy birds and a constant stream of bird calls coming from one place is often the only way of identifying them and their presence. The female lyrebird is also an excellent mimic, but she is not heard as often as the male lyrebird. One researcher, Sydney Curtis, has recorded flute-like lyrebird calls in the vicinity of the New England National Park. Similarly, in 1969, a park ranger, Neville Fenton, recorded a lyrebird song which resembled flute sounds in the New England National Park, near Dorrigo in northern coastal New South Wales.

After much detective work by Fenton, it was discovered that in the 1930s, a flute player living on a farm adjoining the park used to play tunes near his pet lyrebird. The lyrebird adopted the tunes into his repertoire, and retained them after release into the park. Neville Fenton forwarded a tape of his recording to Norman Robinson. Because a lyrebird is able to carry two tunes at the same time, Robinson filtered out one of the tunes and put it on the phonograph for the purposes of analysis. The song represents a modified version of two popular tunes in the 1930s: "The Keel Row" and "Mosquito's Dance". Musicologist David Rothenberg has endorsed this information.

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