If you are training to be a pilot, or simply have an interest in the industry, a phrase that you might have come across is pilot deviation. Pilot deviation is a serious mistake to make when you are piloting a plane, and the consequences could be disastrous.
As a pilot, pilot deviation is something that you should avoid at all costs when possible, but what does it mean? We are going to explain what pilot deviation is in this article, and how serious this violation can be for you.
This should help to give you a better understanding of pilot deviation and the risks that are associated with it. We will also go into the consequences that could occur if you were to get into trouble for this.

What Does Pilot Deviation Mean?
Pilot deviation is when the actions of the pilot result in the violation of a Federal Aviation Regulation or a North American Aerospace Defense Command Air Defense Identification Zone tolerance.
We will leave some of the most common violations below for you to read about.
- IFR Deviations - This is the most common of violations that happens the most often, followed by course or heading, airspeed, and procedural violations.
- VFR Deviations - These violations will involve airspace, altitude, course or heading and airspeed problems.
- TFR Violations
How Bad is Pilot Deviation?
If you are in trouble for pilot deviation, the results could be very bad. The overall outcome will depend on the situation in question and the consequences of the incident. However, the penalties for pilot deviation can be quite severe, which is something that you should be aware of.
If you are aware that you have made a mistake, and have filled out the necessary reports, then it will be less likely that you will face serious consequences.
However, if you are unaware that you have made a mistake, or you have purposely broken the rules, then it is likely that you will have to take part in further testing or remedial training. If you do not, then you might face losing your certificate, which isn’t what anybody wants.
Pilot deviation is a serious incident, and there can be lots of different outcomes depending on the exact situation. The best way to ensure that you do not get in any trouble is to stay vigilant, follow the rules, and file a report if you know that an error has occurred on your behalf.
What is a Brasher Warning?
A brasher warning is basically when you are given notice that you have made a mistake when you were piloting a plane. Essentially, you have the right to be aware that you are in trouble after making a mistake.
If an air traffic controller has determined that the actions of a pilot have affected the safety of operation, then it is the controller’s responsibility to notify the flight crew as soon as it is practical to do so. To do this, they will use the Brasher Notification Phraseology. This is usually in the following format:
(Aircraft identification) POSSIBLE PILOT DEVIATION, ADVISE YOU CONTACT (facility) AT (telephone number). This brasher warning is intended to provide the involved flight crew with the opportunity to make note of the incident that has taken place and gather their thoughts before it is discussed.
If you do receive a brasher warning, you should know that you do not have to call the provided telephone straight away, and you are allowed to take some time to think about the situation that has occurred.
As well as this, you might want to consider making a call to an aviation attorney before you call the number that you have been provided with. This will help to ensure that you are fully prepared for whatever happens next.
What is the Penalty for Pilot Deviation?
As we have previously mentioned, the penalties for pilot deviation can be very severe, and the action itself can often be deadly.
The worst case scenario would not be to lose your certificate. If the worst were to happen, people could lose their lives due to pilot deviation, which is not something that anyone wants to have on their conscience. Pilot deviation can leave passengers, crew, and people on the ground in danger.
Even the simplest of deviations can make the difference between life and death, which is why it is so important to stick to the rules.
Some of the penalties of pilot deviation can be no action, a warning notice or letter of correction, certificate suspension, civil penalties, retraining, and even certificate revocation. It is really important to understand how severe the consequences can be.
When Can You Deviate From an ATC Clearance?
If an ATC clearance has been obtained, there is no pilot that is allowed to deviate from the given clearance unless an amended clearance has been obtained, there is an emergency, or the deviation is in response to an air traffic alert and collision avoidance system resolution advisory.
However, unless you are in a Class A airspace, a pilot is allowed to cancel an IFR flight plan if the operation is being conducted in VFR weather conditions. If the pilot is unsure of an ATC clearance, they can simply request clarification from ATC. Unless there is an emergency, no person should operate an aircraft contrary to an ATC instruction.
As well as this, any pilot in command that deviates from an ATC clearance in an emergency, or in response to a traffic alert and collision avoidance system resolution advisory should notify the ATC of the deviation as soon as possible.
A pilot will be given priority in an emergency situation, and they will need to submit a report of this emergency within 48 hours to the manager of the ATC facility if this is requested of them.
Unless it has been authorized by the ATC, no pilot should operate an aircraft according to any clearance or instruction that has been issued to the pilot of another aircraft.