Rotation is one of the most commonly used terms in aviation. It is the act of applying the inputs needed in an airplane to steer the vehicle from a quick-moving ground-based state to a slow-moving airborne condition.
We will investigate the various questions related to rotation, why pilots say “Rotate”, and the V-speeds of an aircraft.
Why do pilots say V1 rotate?
When inside the flight deck, the two most essential things that concern the crew member are take-off and landing. A safe take-off entails much more than obtaining clearances from air traffic controllers through radio transmission and taxiing down the runway.
While rolling down the runway, the pilots must decide whether to carry on with the take-off or abort the procedure. So they need to calculate the take-off speeds while taxiing down the runway.
These take-off speeds are referred to as V1, Vr, and V2. Pilots need to calculate the correct speed for take-off.
Because these critical indicators determine a pilot’s response to take-off at that speed. V1 is the velocity at which the pilot may have decided to terminate the take-off if the aircraft should cease on the runway.
At this speed, the aircraft cannot safely come to a halt before the end of the runway. If something critical happens during the take-off procedure, the plane can stop till it reaches the V1 speed.
Rotate is the speed at which the pilot lifts the nose of the aircraft, and the plane takes off the ground. This is also called the Vr speed.
These speeds are announced by the pilot not flying the aircraft during the takeoff roll. These speeds are declared quickly since they are only a few knots apart.
During the take-off roll, the airspeed indicator must read up and down straight unless a consequential wind is blown into the pitot tube.
Once V1 is called, the pilot will take their hands off the throttle. This indicates that the take-off will not be aborted under any circumstances now.
Next, the pilot will disengage from the yoke when “Rotate” is called. This will lift the nose of the aircraft, and it will begin to fly.
Commercial flights lift off the ground at speeds between 160 and 180 MPH.
During take-off, the flight crew or flight attendant sit on the jump seats near the emergency exit.
What is v1 in aviation?
V1 is also known as the decision speed. This is the speed beyond which take-off must not be aborted.
It means that the decision to continue the flight has been attained even if the critical engine fails.
V1 is also the maximum speed up to which the plane can be stopped safely without overreaching the runway in an emergency.
When the co-pilot announces V1 at take-off, it means the plane has reached the maximum velocity to stop safely on the runway. And you will see that the First Officer will let go of the engine thrust to concentrate on the yoke or joystick.
In other words, the flying pilot will remove their hands from the power levers.
Once V1 has been called, the pilot must start rotating the aircraft, regardless of an emergency.
There have been several instances when the pilot decided to abort a flight even after a V1 callout. The reasons have been mostly damage, fatalities, and overrun.
In the event of an engine failure, a jumbo jet needs adequate power to go on with the take off with three available engines. So each machine does not have as much stockpile.
In the case of a twin jet, however, the aircraft needs adequate power from only one engine to continue taking off. So the engines have a lot of extra reserves.
V1 is calculated manually by every pilot according to the number of passengers, the cargo load, temperature, obstacles, runway length, runway slope, and the aircraft’s weight.
The airplane manufacturer comes up with these performance figures during aircraft testing. They also provide performance charts that enable a pilot to forecast the take off, ascent, cruise, and the aircraft’s landing performance.
The International Civil Aviation Organization determines operating practices and processes that consider the technical field of aviation.
The rotation speed for every condition is also ascertained during performance testing.
The pilot not flying declares three crucial speeds to the pilot.
These are the following:
- V1
- Vr (rotation)
- V2 (the safety velocity for an engine failure)
It must be noted that V does not stand for velocity, but vitesse. This is a French word used for speed.
V1 rotate v2
The pilot uses three critical speeds during take off.
The first one is called the decision speed at which stopping the aircraft is impossible, and it is committed to fly. This is known as V1.
The second one is the speed at which the nose of the airplane is raised, and turned around into the ascent altitude. This is referred to as Vr.
When the aircraft reaches the Vr velocity, the non-flying pilot announces “Rotate”. This is an indication that the airplane has reached its predetermined rotation speed.
This is the velocity at which the control inputs can be put in. So now, the pilot applies the side stick or aft yoke to elevate the nose of the airplane.
Commercial planes fly at a very high speeds. But their take off and landing speeds are much lower.
Contrary to take off, when the aircraft is descending, its steady alignment with the runway is called the final approach.
What is V2 in aviation?
Known as the takeoff safety speed, V2 is the juncture at which the aircraft can safely ascend even with a non-functional engine. Plus, the aircraft should be able to maintain the V2 speed.
With one engine not functioning, a large aircraft is supposed to rise at least 35 feet. For some smaller aircraft, this height is increased to 50 feet.
The airplane must attain the screen height before the end of the runway. This is the standard height for obstacle clearance.
The takeoff distance comprises two parts. One is the ground run, and the second is the distance from where the aircraft leaves the ground to reach 15 m or 50 feet.
The cumulative value of these two distances is known as the takeoff distance.
Why can’t a plane stop after V1?
After V1 is announced, the aircraft is not left with an adequate runway to stop. So the pilot is committed to taking off.
This is paramount in case the engine fails during take off run. If the speed is below V1, then take-off can be aborted.
In case V1 is called, the pilot has no other option left but to continue with the take-off and then come back for a landing after deploying the landing gear.
However, this is not to say that the pilot cannot stop the aircraft after V1 is announced. V1 remains a tricky question.
Therefore, to call V1, the decision speed may not be totally correct. The initial steps to stop the aircraft should be started at V1 to ensure the plane comes to a halt on the remaining part of the runway.
In other words, the decision to stop should ideally be taken before V1. If the runway is long, it is possible to apply the braking effort and stop the aircraft before it overshoots the runway.
However, this is not a safe option. Because once the plane reaches the Vr speed, it is best to take off.
How does a plane rotate?
There are different theories about rotation. According to the United States FAA flying handbook, when in a nose-wheel aircraft, all the flight controls become operational during the take-off roll, the back elevator pressure is put in place.
This elevates the aircraft’s nose wheel off the ground called the takeoff attitude. This process is known as rotating.
The control surfaces of an aircraft generate aerodynamic forces when in flight. The control surfaces’ pressure center absorbs the aerodynamic forces.
Some distance away from the aircraft’s center of gravity, the control surfaces generate torques around the principal axes. The torques allow the airplane to rotate.
How do pilots know when to rotate?
The co-pilot calls “Rotate” – the verbal cue that the aircraft has arrived at its predetermined rotation speed. Also known as Vr, the flight is ready to take off.
The rotation speed primarily depends on the maximum takeoff weight of the aircraft. This includes all passengers, fuel, cargo, and baggage.
The bulkier an airplane, the higher the rotation speed.
FAQ relating to why pilots say rotate
Why is it called rotate when a plane takes off?
When an aircraft is stationary on the ground, its nose wheel(s) and main wheels are on the floor. The plane starts taxiing, and at some particular velocity, the pilot rotates the nose wheel(s) to lift the aircraft off the ground.
Once the nose wheel(s) leave the ground, the entire weight is on the main wheels. As the plane takes off, all the wheels are lifted off the ground.
The wheels are now retracted up and sequestered. So rotating is the closing step before the aircraft is airborne.
It entails rotating the aircraft approximately 10 degrees around the main wheels’ axis.
This causes the angle of the plane’s wings to change from horizontal to almost vertical.
The ground effect plays a significant role during take off. It positively affects the lifting aspects of an aircraft’s wing’s horizontal surfaces near the ground.
The effect results from the disturbance of the airflow beneath these surfaces, owing to their proximity to the ground.
Planes gradually angle up at the time of taking off. Pilots usually take off opposite the wind direction.
This is beneficial as the airplane receives extra lift from the wind. This is besides the weight of the airplane itself.
The angle between the flight direction and the chord line is called the angle of attack of the wing. It has a significant impact on the lift produced by a wing.
When an aircraft takes off, the pilot applies enough thrust to make the aircraft glide along the runway.
How do pilots know when to rotate?
The pilot applies back pressure to a flight control device, for example, a yoke, center stick, or side stick, to raise the nose of a plane’s wheel. This is known as the rotation of the aircraft.
All airplanes must reach a Vr or rotation speed, following which they can safely take off. The Vr speed is calculated before the take-off.
Why do pilots says heavy?
The word “heavy” in aviation refers to a larger aircraft type. It has a maximum take off weight equalling 160 tonnes or superseding that.
These airplanes’ wings produce wake turbulence. Plus, they need extra separation from the following aircraft, owing to their large size.
The word “heavy,” therefore, is a reminder to other pilots of the same.
The disturbance in the air current that allows a plane to stay afloat sometimes causes the aircraft to shake. Also called air pocket, they result in an abrupt decrease in altitude.
Why do pilots say v1?
V1 is a verbal command which determines that the decision to continue the takeoff has been taken, irrespective of an engine failure.
