Why GPS technology has been a windfall for aviation industry

It is easy to interfere with GPS signals hence countries have to maintain their ground navigation beacons. FILE 

By Daniel Ondieki

In Summary

Since GPS signals can easily be interfered with, countries have to maintain their ground navigation beacons and pilots trained on how to use them.

 

In the past, getting directions in Kenya has been a test of memory and spatial orientation where one had to remember landmarks, various turns, count speed bumps and the like.

Now, for the many Kenyans with smartphones, all they have to do is share their locations using one of the many chat apps.

The recipient can then use the navigation app in their phone and the inbuilt GPS to literally go anywhere. GPS is the best known and most accurate of the global navigation satellite systems.

All these systems work by measuring the time it takes for a signal to travel from a satellite to a receiver on earth.

Multiply this time by the speed of light and you get a distance from the satellite. The receiver, which knows the locations of the satellites, combines the distance from four satellites to come up with a position fix.

While the receivers are cheap and ubiquitous, the rest of the equipment that makes up the system is very costly. Launching anything into space is expensive and all 27 GPS satellites need replacing every few of years.

The US government graciously picks up the tab for the rest of the ungrateful world.

GPS has been a boon to aviation. Previously, airplanes had to fly from one ground based beacon to another. The beacons had limited range, were inaccurate and required a little bit of brain power to use.

Additionally, they required the kind of regular maintenance and calibration that defeats African countries.

Simple to use

GPS, on the other hand, is dead simple to use. It is accurate, has global coverage and is cheap to boot.

Coupled with electronic maps and displays, it is probably safer than the alternatives. For this reason, all pilots have embraced GPS.

Commercial jets still keep the older navigation equipment, but the flight computer prioritises GPS information. This over reliance on GPS has caused some concern.

Probably the biggest issue is that it is fully owned and controlled by the US military. As a consequence they can degrade signal accuracy or switch it off whenever they want.

Due to so many civilian uses, the US has promised that this won’t happen even going as far as not including signal degradation technology in newer satellites.