Cases of aircraft crashing into one another have been heard of before, but did you know that a number of those cases were caused by navigation issues? Navigational issues include the failure of pilots to read the GPS and compass deviations due to electronics used on an aircraft below 10 000 ft. Why did these things occur? What other issues were there that caused navigation related accidents? Don't worry, we'll answer the questions right here.
It is a rare case for pilots to have read the GPS or directions wrongly due to poor training, especially not in the case of IFR pilots. Most of the time it was caused by the misinterpretation of the equipment's feedback to the pilots. This falls into the category of ‘human error' as it was not the fault of the equipment, for example lacking information, but rather the fault of the pilots.
Let's backtrack a little bit and give some insight into what a navigation system is. A GPS, also known as a GPS navigation device, is a device that receives data from GPS satellites in order to calculate and locate the geographical position of the device on Earth. Most, or all, of you, would be familiar with GPS apps on our smartphone such as google maps, Waze, maps, etc. but, did you know that the GPS was initially developed for the US military? This all changed in the 1980s when the US government made GPS available to everyone. Its general purpose is to increase safety and maintain flight efficiency along with locating the geographical position of the aircraft in the atmosphere. In current times, there are even GPS devices that could show the current weather, runway situation, etc. This helps greatly when attempting to land in low visibility scenarios of a certain area.
What are the benefits of flying with a GPS? Why does modern aircrafts have built-in GPS? As GPS is the most reliable and accurate way to geographically locate an aircraft anywhere on Earth, it is safer to fly with a GPS and also cost friendly as GPS helps find the most fuel-efficient route possible. With GPS, airports no longer need to spend extra costs on ground navigational systems and reducing delays, along with helping pilots to land safely especially during low visibility scenarios.
Fast forward to the present time, there has been a number of navigational system related accidents recorded and although the numbers are not major, it is still increasing gradually and only ever so often decreasing. As technology advances, why are there still accidents occurring? Once again, it is due to ‘human error’. Although, it may also be possible that the GPS fails midway. This, however, does not necessarily mean that the aircraft will indefinitely crash onto another aircraft. So, what can we do when the GPS fails mid-flight?
When a GPS fails mid-flight, the pilot is expected to continue the flight heading in which it was following previously. When the aircraft is flown above ground, the pilots will be able to continue with their flight using VOR navigation system. For pilots it is always important to maintain their situational awareness and not really on GPS all too much. The system may fail but good pilotage and flight planning can help the pilot navigate safely even if there is no GPS on board.
One accident occurred on September 3rd, 1989, taking the lives of 13 people and leaving 34 injured. The accident was of the Varig flight Boeing 737-241 that was scheduled to fly to Belém from São Paolo with 6 stopovers. On the flight from Marabá, the 6th stopover before they reached Belém, an error occurred in the reading of the correct headings from the flight plan given by the ATC causing the aircraft to take a longer route. This lead to another problem, fuel exhaustion. Once they have completely run out of fuel, the aircraft’s engine stopped and the aircraft crashed over trees about 50m above ground.
In conclusion, tragic accidents may be avoided if only a little more thought for details were put in during flight. After the accident occurred, a conference was held to showcase the flight plans of the aircraft and it has been found that 15 other cases were found, all with similar causes such as this one. By focusing more on the details of headings, instruments, even the minute ones, pilots may find some oddities and fix any outliers before there is even a chance of an accident happening. Remember, prevention is better than cure!