Last time, we talked about How To Make A Space Mission A Success (Part 1, Part 2). This time, we’d like to talk about a flight. Although it is much simpler than a spacecraft, it requires the same level of effort and profession.
The airline has already given the route available for a long time before the first flight flies. However, the main topic is about a successful flight. So, we need to know the route long before it and look out for predictable bad weather, severe turbulence, etc. Then, after calculating lots of parameters, including the wind direction, the computer or the pilot figures out the exact route and how much fuel they use. There was a 767 that ran out of fuel because someone used the wrong unit to calculate it!
The pilots and the flight attendants have meetings before the flight to discuss the conditions and the preparations. They meet together near the plane. Meanwhile, engineers are checking if something is wrong with the airframe, just like preparing a spacecraft for launch. If anything is not right, a nasty delay (but for your safety) will happen!
The Flight Starts!
Then, the boarding starts and the flight attendants are ready in place. They keep the cabin from being chaotic and let the passengers sit correctly. At the same time, the pilot is checking one last time for any errors. If everything is alright, they will introduce themselves, and the flight attendants will demonstrate the in-flight safety measures. Focus on the speech and the actions once you hear that. And of course, practice un-fastening the seat belt at cruising altitude so that you don’t make a mistake in an emergency!
Also, the cargo is loaded. This step must be done very carefully, or it could mess up with the center of mass. To give you a simpler perspective, if many passengers are in the front, more baggage will be at the rear. The center of mass needs to be as accurate as possible so that the pilots get more control of the plane.
When the plane is well-prepared for the flight, the pilots start the APU and call the ground to pull the aircraft from the apron. After that, the engines start, and the plane begins to taxi. But, don’t expect a smooth ride to the runway because there are at least a few waiting to take-off, especially at a busy airport. So, the plane needs to wait for minutes to roll onto the runway.
Maybe the plane needs to start the engine all the time and use the brakes to control it.
Finally, when it is the plane’s turn, the plane releases the brakes and accelerates through the runway when the engines are at full power. The plane is going really fast, over a hundred knots, but why doesn’t it leave the ground? That’s because the plane is very massive that the V-speeds must be precisely calculated. So if an airline requires measuring your weight before the flight, it’s just for the plane’s balance and your safety.
While some tiny planes only need a car’s speed to lift off, others may need as much as 300 kilometers per hour just to climb. At the moment of liftoff, you might be very excited! The engines still run near full power, accelerating and rising at the same time. But pilots must do this step precisely.
Start a thought experiment. The key is the main gear is in the middle, not the rear. So, what if the plane’s angle of attack were too steep upon take-off? Well, a harmful tailstrike would happen. What’s more, 2 accidents involving the 747 is related to a previous tailstrike, leading to more than 200 deaths each!
Also, even though a tailstrike can’t happen at high altitudes, another scary thing can still occur if the nose was raised too high — a stall. It means the lift made by the wings cannot overcome the aircraft’s weight, resulting in the loss of lift. Many accidents involve stalling, and an A330 fell into the ocean in a normal position due to a deep stall!
The aircraft then climb really fast, and the pilots are managing the engine throttle and the pitch manually. The autopilot is on at a safe altitude, and the passengers won’t be stuck in the seat belt. For what that happens next, check out the next part.