What Does Mayday Call Mean?
Pilots · 5 min read
If you are an ardent movie fanatic, an active reader, or a history enthusiast, you have heard the term mayday at least once in your lifetime.
When it comes to the main sets of rules for piloting an aircraft, there are basically two of them. Each of such sets of rules is completely different from the other, there is fundamental contraposition between them – that’s why the explanation of how such sets are different is most often described as IFR vs VFR.
IFR means the set of Instrument Flight Rules while VFR stands for Visual Flight Rules.
Although the definitions of these terms are sufficiently precise, a lot of people who are about to start pursuing their career in aircraft control find them pretty confusing. And that is not without a reason.
While the precise set of flight rules according to which the flight would operate seems to be an obvious choice, depending on the flight plan, the ability to communicate with the air traffic control, designated route, or, of course, aircraft type, it is nevertheless the choice which can be as confusing as simple it may seem at first.
Some VFR flights may face unforeseen difficulties just because IFR was not selected as an option before the trip – even if it could be.
However, some restrictions which apply to IFR (and there are a lot of them) simply do not exist when talking about VFR. Yet, to be true, such a saying can of course be applied vice-versa.
As we have already mentioned before, Instrument Flight Rules and Visual Flight Rules are two completely different sets of flight rules.
Both international, national, and local regulations define them very precisely, with very little difference between the implementation of them in different regions, mainly, related to the classification of the airspace and some rules regarding the flights in controlled airspace which can slightly vary in different countries.
Below we will try to explain these sets of rules themselves – along with the differences in their implementation.
The majority of commercial flights which are performed today are made possible only because almost every modern aircraft is well-equipped with the best navigational apparatus the latest technology can offer.
Without such equipment flying, as we know it – for example, in the complete darkness, in the fog, in the pouring rain, through, or above the clouds would not be possible because of the absence of outside visual reference during some stages of the flight.
According to the FAA, “an IFR flight depends upon flying by reference to instruments in the flight deck, and navigation is accomplished by reference to electronic signals.” And that is precisely an IFR flying as we know it.
As some handbooks put it, “the majority of IFR navigation is given by ground- and satellite-based systems, while radar vectors are usually reserved by Air Traffic Control for sequencing aircraft for a busy approach or, for example, for transitioning aircraft from takeoff to cruise.”
That is because IFR usually acts as a set of rules for flying the plane in IMC.
Basically, IMC describes the weather and other visibility-related conditions which allows only IFR flying.
To fly IFR, the pilot must meet the qualifications, and that, in other words, is referred to as having an instrument rating. In most jurisdictions, such as the UK and US, to maintain such a rating, the pilot must regularly fly IFR with an aircraft flying the same way regularly.
For example, according to the United States Code of Federal Regulations, (14 CFR 61.57), ‘to file and fly under IFR, a pilot must be instrument-rated and, within the preceding six months, have flown six instrument approaches, as well as holding procedures and course interception and tracking with navaids.’
Not exactly. According to the same Code of Regulations, ‘a flight under IFR beyond six months after meeting these requirements is not permitted; however, currency may be reestablished within the next six months by completing the requirements above. Beyond the twelfth month, examination (“instrument proficiency check”) by an instructor is required.’
Another set of flight rules refers to the way the planes were operated long before the modern navigational equipment started to establish its current place in the pilot’s cockpit. In fact, with some exceptions, quite a usual flight performed back in the second decade of the previous century can be described as a VFR flight.
Therefore, nowadays, almost in the same manner as it was done even more than a century ago, flying under visual flight rules requires no flight plan and can be done by guiding your path according to an outside visual reference.
Just like IFR refers to flying in IMC, VFR flying requires the weather and other outside factors to be in line with VMC, or Visual Meteorological Conditions.
As pointed out by ICAO Annex 2: Rules of the Air, Visual meteorological conditions (VMC) are the meteorological conditions expressed in terms of visibility, distance from cloud, and ceiling equal to or better than specified minimal numbers.
According to the abovementioned rules, essentially, VMC is referred to the heights above 3,000 ft or 1,000 ft above the terrain, whichever is higher. That also means 1500 m horizontally and 1,000 ft vertically from the cloud. There are also specific rules regarding flight visibility, namely 5 km below 10,000ft and 8 km above 10,000 ft.
As a matter of fact, there are much fewer requirements in such a situation. Not only is there no obvious need to file an IFR flight plan, but VFR flying can also be done by any pilot who has at least a private pilot license.
That is, because, to obtain one in almost any jurisdiction, you must perfectly know the basic set of flight rules – both in theory and in practice – which is just enough to perform a VFR flight. In fact, you are already flying VFR as early as when you are just a student on your path to becoming at least a private pilot.
So, to put it simply, VFR pilot restrictions are as low as virtually any basic restrictions for anyone willing to obtain a license for private flying. While that does not mean very little, it can be said that, in fact, any pilot can fly VFR.
The simplest planes, which are not equipped with top-notch navigational and communication equipment, such as small airplanes, light planes, and so on, can fly under VFR.
However, the limitations of such equipment – or simply the lack of it, often subject VFR flying aircraft to a lot of limitations.
Naturally, such limitations include not only operation in poor visibility, flying in clouds, or, as a result, above them, or even flying higher than VMC allows the pilot (and subsequently, an aircraft) to fly.
Such limitations are also related to flying in controlled airspace, which not only means everywhere above 18,000 feet, as in the example of the United States, but also in some areas which are restricted due to the specific activity or, for example, exceptionally high air traffic intensity.
To perform an instrument flight, an aircraft must not only be equipped with the necessary communicational and navigational IFR instruments – but it must also be officially type-certified and all such equipment must be inspected in a timely manner.
In most jurisdictions, it also has to be tested within a specific period of time prior to the instrument flight – in order to be cleared for such.
While, for example, all the airline pilots have flown VFR at one or another point in their life (at least during some stages of their flight training), some spend their entire career – for example, as a commercial pilot, flying just as IFR pilot. And that is why a lot of pilots will probably tell you that VFR and IFR have some similarities – besides the fact that both VFR and IFR sets of rules refer to flying, performing a flight in IFR is not necessarily harder than flying VFR.
Yet, it is obviously harder to become one who can actually be described as an IFR pilot. And not just because all IFR pilots, in fact, can be also VFR pilots.
In fact, there are a lot of situations where both the pilot and the plane can fly VFR while also being certified for flying IFR. Of course, in such circumstances, one can choose.
Yet, the choice is usually limited when it comes to research regarding the path of the journey, the flight plan, actual meteorological conditions, or weather forecast. However, in such a situation you can just choose to fly VFR and fly accordingly – avoid the clouds, controlled airspace, etc. – just like all the VFR pilots do.
After all, you do not have to fill in an IFR flight plan, maintain all the communication needed for an IFR flight, and maybe even recall the good old days of being just a student in the private pilot school during the first months of your flight training.