The APS4A is an add-on LRU that activates the autopilot’s altitude hold mode when triggered by the PFD Pro’s altitude alerter output. When discussing the APS4A with customers, it is important to note that the APS4A does not anticipate the altitude capture point, it simply engages the autopilot’s ALT HOLD mode when the altitude alerter output is triggered.
The EFD1000 PFD – APS4A to Bendix/King KFC200 interface is approved by Aspen’s AML-STC, the details of the KFC200 integration are outlined in Appendix G of the EFD1000/500 Installation Manual. Other autopilots are also compatible with the APS4A but, interfaces with other autopilots or EFIS requires separate approval. A complete list of compatible autopilots is shown in the attached APS4A technical data sheet and installation manual.
When combined with a compatible PFD the APS4A meets the functional requirements required by TSO- C9 and TSOC-52b. For more information contact me: