|Pro Pilot design features that
enhance flight safety.
Automatic 180 Degree Turn
Designed to assist VFR pilots who might unexpectedly encounter poor weather or low visibility, the "auto 180" has been credited with saving lives. This feature was invented by Chuck Busch in 2003 and originally incorporated into the EZ Pilot autopilot. Reports from our customers indicate that it has been put to good use many times. Other autopilots are beginning to emulate this feature.
To invoke the "Auto 180", the pilot simply presses the H MODE button and holds it in for 3 seconds. After 3 seconds the aircraft will initiate a 180 degree turn. It always turns to the right (for consistency). It can be instructed to turn left by also pressing the encoder knob while holding in the H MODE button.
It is important to note that the autopilot does not have to be engaged to utilize the "Auto 180" feature. If a pilot encounters bad weather (and perhaps becomes disoriented) while manually flying the aircraft, invoking the feature will cause the autopilot to check the course over the ground, turn on the servo, level the wings, and execute the 180 degree turn. In the Pro Pilot, it will also engage the Altitude Hold to maintain the current altitude.
"G" Force Limiting
In the event the aircraft experiences abnormal G forces while under autopilot control, the Pro Pilot system is designed to automatically disconnect the pitch servo from the control system before structural damage can occur. It will sound an alarm and disconnect if it senses a sustained vertical acceleration (+ or -) of 1 G for more than a few seconds. In turbulence, it will tolerate stronger, short-interval G excursions without disconnecting. However, if severe turbulence is encountered it will disconnect when the intensity approaches that which dictates that the pilot should be in control of the aircraft.
Min/Max Airspeed Limiting
An internal airspeed sensor (connected to the pitot system) monitors preset airspeed limits (set by the pilot) to prevent the system from stalling or over-speeding the aircraft. Example: If the pilot enters a very high climb rate, as the airplane reaches the minimum airspeed the autopilot will lower the nose of the aircraft and continue the climb at that airspeed, rather than the commanded vertical rate. In the same manner, during a descent, if the airspeed reaches the maximum limit that has been preset by the pilot the nose will rise and the descent will continue at the maximum airspeed instead of the selected vertical rate.
Selectable Track Offset Position (TOP)
If you are on a flight plan using published airways, you may expect to encounter other airplanes using the same airway. While this usually occurs during climb or descent (you or the opposing aircraft) it is a potential safety issue. As more aircraft are using precision GPS receivers to navigate, and many are coupled to autopilots, such close encounters are likely to increase. For this reason, the Pro Pilot incorporates a Track Offset Position (TOP) feature that allows the pilot to select a track offset of up to 3 nautical miles when in the Track (TRK) mode. This places the aircraft away from the course centerline where much of the traffic might be found. It might be noted that if all aircraft positioned themselves to the right of the published course centerline (for instance), opposing traffic would always be on the opposite side of the centerline.
Automatic Servo Disconnect on Takeoff
As a safety feature, during takeoff roll, the Pro Pilot checks the status of the servo. If the servo has inadvertently been turned on prior to takeoff, at 25 knots GPS groundspeed it will automatically disconnect the servo, allowing free movement of the ailerons. This is a backup feature only and should not be relied upon to replace a necessary preflight checklist item. This feature relies on a proper GPS signal being received and will not function properly if the GPS is not active and providing data to the autopilot. GPS groundspeed is used instead of pitot airspeed because airspeed sensors are not very accurate at the bottom end of the range.
Battery Backup (option)
An optional safety measure that will be of interest to IFR pilots is a battery backup system that can power both the autopilot and a backup (portable) GPS system for up to 1-1/2 hours. This provides a valuable alternative, should a power failure occur that disable other electronic instruments such as a primary EFIS system. Without a functioning spatial reference system, the autopilot may be the single best hope for safe flight to VFR conditions.
Gold Standard Servos
Trio's Gold Standard Servo provides numerous features not found on other servos. It incorporates two microprocessors that monitor critical parameters to report to the control head. Its inherent "intelligence" also allows the servo to detect communication errors and disconnect itself from the controls. It will also autonomously disconnect if it senses over-current, over-voltage or temperature problems within the servo. Click on the link for full details.