How does a tiny bird manage to damage a hefty Airbus 320 passenger plane upon collision? In the sky, a regular passenger plane flies at speeds ranging from 200 to 900 kilometers per hour. The obvious question arises: how can a plane flying at such high speeds suffer damage from a bird weighing half a kilo, one kilo, or even two kilos?
Before delving into the damage, let's consider an empty Airbus 320’s weight, which stands between 40,000 to 44,000 kilos. When airborne, the maximum weight can reach up to 77,000 kilos.
A bird colliding with an airborne aircraft is referred to as a bird strike, and it can cause significant damage. This damage is attributed to the kinetic energy involved in the collision, driven by both the bird’s speed and the aircraft’s high velocity, rather than the bird’s size.
On Monday, a similar incident nearly happened in Ranchi, when an Indigo aircraft traveling from Patna to Kolkata encountered a bird strike with a vulture. At this moment, the aircraft was about 22 kilometers from Ranchi Airport, flying at an altitude between 3000 to 4000 feet.
Following the collision, an emergency landing was necessary. Photographs revealed that the frontal section of the aircraft was damaged. However, the emergency landing was successful, and fortunately, no one suffered injuries.
How Does Damage Occur?
The lingering question remains: why is the damage from such a small bird collision so severe and destructive? This is all a play of science.
A bird striking an aircraft traveling at speeds of 200 to 900 km/h generates tremendous kinetic energy (Kinetic Energy = ½ mv²). In this equation, M signifies mass, meaning weight, and V signifies velocity, indicating relative speed.
Generally, when a plane flies at speeds between 200 to 900 km/h, even if a bird weighs only a kilo, the kinetic energy from the collision is immense.
Source: aajtak
For example, when a plane traveling at 300 km/h gets hit by a one-kilo bird, the force can be about 3400 newtons, akin to the strike of a heavy hammer. It's noteworthy that newton is a unit of force.
Let’s consider another example. A 4-kilo bird colliding with a plane moving at 500 km/h can generate significant energy. At such speeds, even a small bird can exert a force equivalent to thousands of pounds on an aircraft.
Since a bird hits only a small section of the plane, the energy impacts just that tiny portion, leading to damage in that specific part.
Imagine a 25 to 50-gram stone fragment hitting a body part at extreme velocity. Despite the stone weighing just 25 to 50 grams, the high speed substantially enhances its striking capability.
Research further suggests that a 1.8-kilo bird striking a plane produces a force roughly 130 times that of a bullet. According to ABC Science, a 5-kilo bird hitting a plane at 275 km/h is comparable to a 100-kilo weight falling 15 meters onto the ground.
Thus, bird strikes pose perilous threats, potentially inviting disaster and endangering lives.
How Do Bird Strikes Damage Aircraft?
Bird strikes primarily threaten the aircraft’s
engines
. Modern jet engines, although powerful, are delicate. Birds can damage fan blades or compressors upon entering the engine, leading to malfunctions or even fires. For instance, a bird impacting a turbofan engine can cause blades to bend or break, leaving the plane dangerously imbalanced during flight.
Source: aajtak
Windshields/Cockpit:
Aircraft windshields are designed to withstand pressure and collision, yet high-speed collisions with large birds or flocks can shatter or crack them, potentially injuring pilots or obstructing their vision.
Sensors:
Birds can damage crucial instruments like the pitot tube, which measures airspeed, causing erroneous readings and navigation issues.
Although bird strikes occur less frequently while planes are at high altitudes cruising, such collisions can be extremely hazardous if they happen at these speeds. At cruise speed, planes fly at 800-900 km/h, and a collision at this speed yields a substantial impact.
