Most of us are pretty familiar with GPS systems that operate in our cars and on our devices, but when it comes to aviation it’s more complicated than we might think.
Modern private jets don’t simply follow GPS to get where they are going, they actually combine multiple sophisticated navigation technologies that work together to ensure every flight is safe, efficient, and beyond precise.
For this blog, we asked Josh Dodd of Calgary based Avionco to give us an idea of the technologies that are employed by his pilots as they serve private jet owners around the world.
Navigation Has Come a Long Way
Today’s business jets use advanced digital navigation systems that continuously calculate the aircraft’s position using satellites, onboard sensors, and powerful flight computers. The result is shorter routes, lower fuel consumption, smoother arrivals, and access to airports that would have been difficult or even impossible to reach decades ago.
GPS and Three-Dimensional Space
As mentioned earlier, most people are familiar with GPS from their smartphones or car navigation systems. Aircraft GPS works on the same basic principle but is incredibly more sophisticated.
Navigation satellites orbiting Earth constantly transmit precise timing signals to aircraft GPS. The aircraft receiving a signal compares it to information being broadcast from multiple satellites and calculates its exact position in three-dimensional space.
Today’s aviation GPS systems can determine:
- Latitude and longitude
- Altitude
- Ground speed
- Direction of travel
- Time to destination
- Estimated fuel remaining at arrival
Because aviation-certified GPS equipment must meet extremely rigorous standards, it is significantly more reliable and accurate than consumer GPS devices.
What some of us may not realize is that it’s only one piece of the puzzle when it comes to aviation.
The Inertial Navigator
What happens if GPS signals become temporarily unavailable? That’s where something called INS – Inertial Navigation System takes over.
Unlike GPS, the INS doesn’t rely on anything outside the aircraft. Instead, it continuously measures the aircraft’s movement using extremely sensitive accelerometers and laser or fiber-optic gyroscopes. These work like incredibly sophisticated motion detectors.
Once the aircraft’s starting position is entered prior to departure, the INS constantly calculates every acceleration, turn, climb, and descent. By adding these movements together thousands of times every second, it always knows approximately where the aircraft is. Even if satellite signals disappear for several minutes, the aircraft continues navigating accurately.
Modern business jets actually compare GPS and INS data continuously. If one system detects a discrepancy, the other helps verify the aircraft’s true position. This programmed redundancy is one reason modern aviation is so exceptionally safe.
But there’s even more at work here.
FMS – The Brain of the Operation
Neither GPS nor INS actually flies the airplane. That responsibility belongs to the Flight Management System (FMS).
Before departure, pilots load their planned route into the FMS. This includes:
- Departure procedures
- Airways
- Waypoints
- Cruise altitude
- Arrival procedures
- Instrument approach into the destination airport
The FMS then combines information from GPS, INS, air data computers, weather radar, engine systems, and dozens of other sensors.
The result is a constantly updated picture of where the aircraft is AND exactly where it should be going next.
The FMS also provides guidance to the autopilot, allowing the aircraft to fly highly accurate routes while pilots continuously monitor every phase of flight.
Changing Routes During Flight
One of the biggest advantages of modern flight management systems is flexibility.
There may be several reasons to deviate from a planned route during any flight:
- A shortcut to save time
- A reroute around storms
- A temporary airspace restriction
- A different arrival procedure
- Holding instructions due to traffic
To do so, pilots enter new data into the FMS and within seconds, the aircraft recalculates:
- Remaining distance
- Estimated arrival time
- Fuel burn
- New headings
- Vertical profile
The system immediately guides the aircraft along the revised route.
What is RNP?
Major airports may have hundreds of arrivals and departures every hour, while remote regions often have little or no ground-based navigation infrastructure. This makes something called Required Navigation Performance (RNP) especially important.
RNP is essentially a measure of how accurately an aircraft must be able to fly a specific route. For example, “RNP 1” means the aircraft must remain within one nautical mile of its planned path. “RNP 0.3” requires the aircraft to remain within just three-tenths of a nautical mile. Some specialized approaches demand even greater precision.
To achieve this, the aircraft continuously monitors its own navigation accuracy. If it cannot guarantee the required level of precision, pilots are immediately alerted and another procedure is used.
This capability allows private jets to safely fly approaches through mountainous terrain, narrow valleys, or airports with limited ground navigation equipment.
Navigation Accuracy Saves Money
Highly accurate navigation allows aircraft to:
- Fly more direct routes
- Reduce fuel consumption
- Lower operating costs
- Minimize emissions
- Spend less time in holding patterns
- Avoid unnecessary detours
Owner’s, Operators, Corporations and Charter Services are all interested in managing the bottom line to make flying as financially efficient as possible.
About Avionco
Formed in 2000 by Mike Dodd and Josh Dodd in Calgary, Avionco is a premier aircraft services provider, purpose-built to serve aircraft owners whose business and lifestyle needs require impeccable service and efficiency in everything they do.
Josh Dodd, COO, leads day to day operations with a team of dedicated senior management professionals delivering a complete suite of flight management services including Pilot and Crew selection, In-Flight and Ground Operations, Safety and Compliance, and Entry Into Service (EIS). Learn more at www.avionco.com