Not all of this year's "surprises," at the highly successful 2004 rendition of the Aircraft Electronics Association's Tradeshow/Convention were expected to be quite this cool... even by the nosy folks at ANN.

Chelton introduced a somewhat novel new autopilot system that leaves little to want for, once the initial install is over. Jam-packed with features and capabilities, the Chelton AP-3C diverges from the norm in that pitch attitude control is derived from pitch trim motivation. Unlike many light GA autopilots, the AP-3C does NOT use a pitch servo to drive the elevator. Pitch attitude is, instead, controlled by servos driving the pitch trim system itself... and keeps your airplane "in trim" while the autopilot is driving your bird. Just think of how many times you've had to re-trim your airplane upon autopilot disconnect and you can get a gander at how convenient this aspect might be.

Vertical modes include selected pitch angle stabilization, altitude hold, automatic glide slope capture and tracking. Lateral modes include selected roll angle stabilization, and automatic capture and tracking of heading, VOR/Localizer, back course and GPS or Loran courses.

Automatic Computed Navigation System (CNS) tracking is provided for flight plan and approach steering, using signals from all popular models of GPS navigators and flight management systems which provide such information. The AP-3C autopilot can provide both horizontal and vertical GPS approach coupling with WAAS capable GPS receivers.

Control Wheel Steering, automatic pitch trim and full-time manual electric pitch trim are standard features of the AP-3C. It also includes a unique mode, which provides automatic recovery from adverse attitudes.

A single panel mounted control/annunciator unit is used that requires NO external adapters, altitude sensors, or the like. This intensely simple system requires equally simple cabling and wiring support and its servo actuator assemblies are smaller and lighter than those used in comparable systems. Chelton notes that these servos can be separated from their capstan plates, which remain in place to hold the control cables -- meaning that during installation, the technician has to deal only with the positioning of the plate, AND that the aircraft is STILL flyable even if the servos are removed for servicing.

The AP-3C has only three components... the autopilot unit, itself, and a roll and pitch trim servo -- which are electric, brushless, metal and uses no (fragile) plastic gearing with a lengthy MTBF of 7500 hours. Already developing dozens of STCs for this exciting product, the $12,995 AP-3C features modern surface mount, solid-state components and meets FAA TSO C9c standards in both the United States and Europe. STCs for two additional aircraft series are being obtained each month.

The Stats: 

Supported System Interfaces:

• Any vacuum or electric attitude gyro with ARINC 5 kHz outputs
• Any vacuum or electric directional gyro or HSI with ARINC 5 kHz outputs
• Any vacuum or electric directional gyro or HSI with ARINC DC outputs
• Any NAV receiver (VOR/LOC/GPS/LORAN) with standard 150 mv left/right deviation outputs
• Any glide slope receiver with standard 150 mv up/down deviation signals

FMI: www.chelton.com