Text based GPS systems have been used for many years within General Aviation. The availability of computing systems required to display moving maps and process navigation databases has enabled the GA TAA aircraft to become a complex environment for which training devices are almost essential.

A flight training device that emulates a TAA must be able to provide facilities for entering, monitoring and commanding guidance for flying flight plan legs, holds and glideslopes. It must provide the same keyboard, touchscreen, button and knob selection methodology as well as look and feel as the aircraft unit. 

The Cirrus is on the glideslope and centerline just after the final approach fix on its way to completing another coupled approach at E16.

FlyThisSim products all use the same SimAVIO core software . SimAVIO is independent of other programs except for real time state and dynamics data provided by the host simulator.

Equipment specific graphics and behavior modeling are defined in customizable data files read by SimAVIO providing a unique capability to simulate GPS systems from a wide variety of manufacturers.

Going Missed. FTS 430 simulation driving our simulated Avidyne MFD. The beginning of the Direct To anticipates the aircraft turn radius, the hold shows a predicted teardrop entry for a one minute hold sized appropriately for aircraft TAS. 

Few simulator manufacturers have the capability or time to invest in producing an accurate GPS/FMS simulation and instead revert to installing real aircraft equipment. FlyThisSim believe this is wrong and simulation has clear advantages over stimulation.

Cost

• Aircraft units are expensive.   Add the cost of software and the hardware integration for data, mechanical and electrical interfaces and stimulation becomes very expensive.
• Simulations provide a system that meet training requirements at lower cost.   Development costs are amortized over the life of the product.  With the exception of instrument bezels, simulations require no special hardware or software interfacing. 

Adaptability

• Stimulated aircraft units are configured specifically for an aircraft.    For example, the C172 and C182 G1000s have different firmware that cannot be changed automatically.    Changing from a G1000 to an Avidyne is obviously impossible.
• Stimulated units become outdated as new versions are released.   With simulated avionics, only a low cost software upgrade is required, reducing the risk of obsolescence.
• A simulation can automatically switch between aircraft types and equipment manufacturers.   As aircraft units are upgraded, so is the simulation. 

Maintainability

• If a stimulated aircraft unit fails, an expensive replacement is required, accompanied by long downtimes as the replacement is procured.
• Failure of a simulated system most likely occurs from the failure of a general purpose computer component.   The system can return to service in minutes or hours, and at a much lower cost. 

Fidelity

• The discussion would not be complete without what some consider the Achilles heel of simulation.   If an aircraft unit is fitted, it must look, feel and behave exactly as the aircraft.   Look and feel is generally subjective.   But operational behavior is not guaranteed.
• The equipment still must interface to simulated systems, particularly the autopilot.   The interaction between these systems is critical for high fidelity simulation.   Because the aircraft unit is a black box, full integration with the simulator can be impractical.    Simulated malfunctions can be particularly difficult to implement and limited in scope.
• Aircraft units are not designed to work in a simulator. Slewing of simulated position, infinite acceleration and other unrealistic behaviors are detected by the unit.   This can lead to 'GPS Unreliable' annunciations and un-commanded autopilot disconnections.   For certain malfunctions, the equipment must re-initiate start-up sequences and re-entry of flight plans.
• With a software based simulation non of these limitations are apparent. 

A Good Simulation is the Best Choice.   A simulated GPS system may not provide all of the functions of a real unit but it will provide those required to train pilots, usually without limitation. When the cost, maintainability and adaptability accounting is considered,  it is difficult to justify using an aircraft unit for simulation.

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