Land after procedure: what is a first line landing of an aircraft, and is it safe for passengers and crew

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Land after procedure: what is a first line landing of an aircraft, and is it safe for passengers and crew
Land after procedure: what is a first line landing of an aircraft, and is it safe for passengers and crew
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In order to understand why the Land after procedure was introduced (landing of an aircraft in a “first-come, first-hand order”), it is necessary to understand the mechanism of a conventional go-around landing. They are closely interconnected. The Land after procedure is not always applied, but it is important, which should be known not only to pilots, but also to passengers in order to avoid unnecessary panic.

Land after procedure is not always applied, but it is important
Land after procedure is not always applied, but it is important

1. Standard landing procedure

The standard landing procedure is as follows: the plane drops altitude along the glide path, mechanization and landing gear are released, a clearance comes from the controller, a landing or go-around is performed
The standard landing procedure is as follows: the plane drops altitude along the glide path, mechanization and landing gear are released, a clearance comes from the controller, a landing or go-around is performed

In this case, the algorithm of actions is simple. The plane drops altitude along the glide path, mechanization and landing gear are released, and permission comes from the dispatcher. At a certain altitude, the factors are assessed, after which the aircraft itself is landed.

Standard aircraft landing with missed approach
Standard aircraft landing with missed approach

In case of any interference, the aircraft makes a go-around. In such a situation, there are no problems with leaving. The engine mode, like the speed, is quite high. The engines are given a take-off mode, and the car will go into a set with a minimum drawdown. If this decision is made after the threshold of the runway (runway) is passed, when the height is less than thirty feet (approximately 9 meters), some difficulties arise.

A go-around requires additional consumption of aircraft resources, passenger time and crew forces
A go-around requires additional consumption of aircraft resources, passenger time and crew forces

First, at such an altitude, the engine mode is tidied up and it will take time for the reverse spin-up, even if the process takes seconds. Second, the speed also decreases, which means it takes time to accelerate it to V2 (safe climb speed). It is unlikely that it will be possible to avoid touching the strip here.

The controller allows the ship to land only if the runway is clear, up to the height when the decision is made
The controller allows the ship to land only if the runway is clear, up to the height when the decision is made

In practice, the following situation turns out. The controller will only allow the ship to land if the runway is clear, up to the height at which the decision is made. As a result, the situation is quite real when the plane that had landed before almost left the runway, and the second landing was forbidden, and he had to go around. And if the dispatcher had waited a few seconds, this plane could have made a landing (technical moment).

To increase the throughput of the runway, a "land after" procedure was introduced
To increase the throughput of the runway, a "land after" procedure was introduced

At the same time, in a normal situation, the crew receives permission to land the ship in advance, long before any difficulties arise with leaving. As a result, the throughput of the runway is significantly reduced. In this regard, the “land after” procedure was introduced.

2. How it works

The controller does not issue permission to land
The controller does not issue permission to land

There are no difficulties in the algorithm of actions in the case of this procedure either, but sometimes the crew has to get nervous.

The dispatcher does not issue permission to land, but, for example, "… land after B737, runway 18 left …", which means "… landing behind B737, lane 18 left …". The crew must answer in the format "Land after the B737 …" - "Landing behind the B737".

After this dialogue, responsibility from the dispatcher for any force majeure situations is removed and transferred exclusively to the crew
After this dialogue, responsibility from the dispatcher for any force majeure situations is removed and transferred exclusively to the crew

After this dialogue, responsibility from the dispatcher for any force majeure situations is removed and transferred exclusively to the crew. At such moments, the crew has to be quite worried, since it is not clear who is sitting in the cockpit of the first aircraft and how quickly the pilot will orient himself in which direction it is necessary to leave in order to free the runway.

The Land after procedure has some limitations
The Land after procedure has some limitations

Well, if on the first board they will think a little longer what and how to do, the second will have to take care of it. But such cases are extremely rare. This is more the exception to the rule than the rule itself. But this procedure has its limitations:

  • the length of the runway must be sufficient;

  • the time of day should be bright;
  • the second plane is able to constantly keep the first one in sight until it leaves the runway;
  • the first aircraft must be warned.
  • Passengers don't need to worry knowing that the Land after procedure can be applied
    Passengers don't need to worry knowing that the Land after procedure can be applied

    And the most important thing! The procedure is not dangerous at all, and it makes it possible to significantly increase the throughput. Therefore, passengers should not worry, knowing that the Land after procedure can be applied, as it will significantly reduce the time spent in flight.

    Continuing the topic, read how 8 ambiguous accidents were never explained.

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