The radome and the weather radar in aeroplanes

The radome and the weather radar in aeroplanes

The radome is one of the parts of aeroplanes that fulfils various functions at once, that is, it completes the aerodynamic shape of the fuselage and holds and protects the airborne weather radar or AWR, amongst other functions.

Commercial aeroplanes fly at an altitude of over 12 kilometers and just as we saw in our article about the different layers of the atmosphere, at these heights, the majority of meteorological phenomena takes place.

It is primordial, therefore, that aeroplanes have a system to avoid bad weather, but how do radome and aircraft weather radar work? Remember all the details we give below!

Contents

What is the radome of aeroplanes
The onboard AWR or Airborne Weather Radar
- But how does an AWR work?
What is under a radome
What an AWR or weather radar is for
Precautions when using AWR under the radome
Did you expect the radome to be so important?

What is the radome of aeroplanes

Generally speaking, radome is the cover used to protect a telecommunications aerial. In aviation, radome is the ‘nose’ of an aeroplane where the airborne weather radar or AWR is hidden.

A radome has the shape of a cone with a round tip; it is coated with a special paint that allows radar waves from the weather radar to go through it without interference.

As we have said in advance, radomes provide the arrowhead shape to aeroplanes to make them more aerodynamic and thus, increase their flying efficiency.

The onboard AWR or Airborne Weather Radar

Commercial aeroplanes are equipped with what is known as Airborne Weather Radar or AWR. It is an onboard meteorological radar that allows pilots to identify quickly and intuitively the areas with severe weather conditions.

But how does an AWR work?

The onboard weather radar is a primary radar that uses rebound waves once they crash against water droplets, in order to detect their presence.

Nowadays, the majority of radars also use the Doppler effect that is generated allowing water droplets speed to be obtained, which can predict turbulences.

In order to carry out these measurements, weather radars emit radio waves in the super high frequency spectrum, around 9 GHz.

What is under a radome

Underneath a radome, the weather radar is connected to a directional aerial which allows for longitudinal scans to each side of the nose of the aeroplane, as well as vertical plane scans. This function is of great help when making either an ascent or descent.

In flight, once pilots have detected their route passes through a bad weather area, they will request ATCs to divert their route 5º, 10º or 15º with respect to their original direction.

When this happens in ascents or descents, other options available are to increase the ascent or slightly delay the point at which to start descent.

Options depend on the situation in which it is produced and their aim is to increase safety as much as possible.

Additionally, more modern aeroplanes, such as Airbus A320Neo, allow automatic selection of flight level, making the indication even more accurate.

Information obtained through the AWR is shown to pilots following a range of colours that relate to the intensity of the weather phenomenon: green for light precipitation and purple for severe precipitation.

What an AWR or weather radar is for

Without a doubt, meteorology is an essential factor when planning a flight. This is why the onboard weather radar integrated beneath the radome is in charge of providing pilots with the required information so they can avoid adverse meteorology phenomena.

Strong Wind

When there’s a strong headwind, fuel consumption can increase substantially or going through a pocket of turbulence will unnecessarily make the flight uncomfortable for passengers.

Hail

Flying through strong hail can damage the outside of the fuselage. Can you see, then, how important radome and weather radar are?

Thunderstorms

As with hail, although aeroplanes are designed to endure lightening impact, when it actually happens, a more exhaustive service of the aeroplane is needed in order to check everything is as it should be. And, of course, all these checks mean loss of time and money for the airline involved.

Ice

Another one of the negative effects of going through adverse meteorological conditions is ice accumulation; as we already discussed in our post ice is one of the biggest threats for any aeroplane.

You can click on the linked post above to find out more about this and the de-icing of aeroplanes to find out more about the methods to stop this problem, both in flight as well as on ground before take off.

Precautions when using AWR under the radome

As we explained earlier, the weather radar operates at very high frequencies and the radome does not offer any resistance to waves; for this reason we have to take special precautions.

The most important thing is not to activate the weather radar until the aeroplane is entering the runway for take-off.

Keep in mind that, at an airport, there is various traffic circulating simultaneously; if it all emitted such high levels of radiation, after some time, it would cause health problems to ground staff and would be a great hazard for refuelling operations.

As we usually say, everything is meticulously planned in aviation.

Did you expect the radome to be so important?

Weather radars are an essential part of the safety of modern aviation, and now you know they are underneath the radome.

Of course, all pilots know how to use an AWR correctly to guarantee the safety of the flight.

We hope you have enjoyed this post and found it useful. We invite you to continue to explore our aviation blog where you can read about how clouds are formed, what turbulent wake is or how airspace is divided so all traffic can coexist safely.

The radome and the weather radar in aeroplanes

What is the radome of aeroplanes