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FAQ PPAS® (General)

Does PPAS® really work?
Yes. PPAS® uses the same approach that manufacturers of FMCS/PMS systems currently use on newer technology Boeing and Airbus aircraft. PPAS® computations are based on the aerodynamic and specific range characteristics of the aircraft as described in the manufacturer's performance engineering handbooks. (AASI actually goes one step further by re-engineering the manufacturers' databases when required, to accurately reflect true performance and then further adjusts the data for aircraft age.) In all cases data generated by PPAS® is equal to or better than FMCS/PMS data.

Will PPAS® save money
Yes. The PPAS® will save money in exactly the same way as FMCS/PMS systems save money. It will recommend faster speeds in headwinds and slower speeds in tailwinds. This concept allows airlines to fly more efficiently by saving fuel in tailwind conditions and save money (by reducing time in headwind conditions). However, the altitude selection algorithm built into PPAS® is superior to that of current FMCS systems, and therefore will provide more savings.

Will PPAS® save fuel?
Yes. In a tailwind situation PPAS® will recommend a lower Mach number (with a resulting lower fuel burn) and will take advantage of the increased groundspeed to maintain schedule. PPAS® allows the operator to accelerate a particular flight in the most efficient manner to make up for lost time. Profiles will burn less fuel than any other profile for the same flight time and/or will result in shorter flight times than can be achieved with other flight profiles.

Is the interface intuitive?
Yes. The interface has been designed by pilots for pilots. Basic principles of electronic flight instrumentation (EFIS) are used, with airspeed on the left and altitude on the right. Industry standard colour conventions are also applied. The interface is also broken down in phase of flight with simple tabs used to select regimes such as configuration, climb, cruise, descent and hold. Training is minimal and the QRH and Help functions also describe the PPAS® functionality.

Why not just use a good flight plan or flight release?
For an efficient operation, you need both a good flight plan and a real-time flight management system. The flight plan should provide accurate wind prediction and optimal flight path information. However, regardless of how good the flight plan is, there is still a requirement for a tactical system to manage the flight as it progresses. The winds may not be as forecast, the weight may be different than flight planned, or the optimal altitude may not be available. Crews must be able to respond confidently to tactical ATC requests. For instance, if they are required to operate at minimum speed or maintain a particular altitude in turbulence PPAS® will provide buffet protected speed data and instantly pinpoint all aerodynamic limits. Accurate descent planning is also very important for fuel savings, and most flight plans do not give that information. These exigencies mandate installation of a real time flight management system. This has been acknowledged by the industry by the installation of FMCS systems in all new transport aircraft. PPAS® is analogous to the FMCS in its vertical profile optimization, but will achieve the same or better savings because of superior altitude selection.

How effective is PPAS®?
PPAS® is so effective in identifying minimum safe speeds, reducing costs, and maximizing productivity that airlines have started to incorporate PPAS® directly into their approved Standard Operating Procedures. It has become the way they fly their aircraft every day.