Sorry, Bob, while we haven't analyzed your design as you had hoped, we have verbally given you some basic feedback about it. To summarize, we feel as if your design is too complex and is beyond the scope of uses for which the VP-X was designed. The VP-X has always been engineered and marketed as dramatically improving the build and maintenance experience for experimental builders. It is not designed to provide all of the redundancy one might expect in an airliner.
We recognize that sometimes such complexity really is required (depending on the mission and required fault tolerance of the aircraft), and in fact we specifically support full dual-bus architectures in both our original VP-200 (developed seven years ago) as well as our most recent VP-400 (shipping in quantity just within the last few months). Those products are capable of managing two fully-redundant busses, with independent alternators and batteries, and with a cross-tie contactor for moving power from either bus to the other. Our experience developing the dual-bus support in those products has taught us that the additional complexity such systems introduce is not required by the vast majority of our customers. That is what led to the VP-X in the first place.
By reducing the part count and simplifying its options for integration, the VP-X has been proven capable and valuable to many customers. However, because we recognize there is still a desire to improve how the VP-X handles certain kinds of rare failures, we extensively document two different backup e-bus architectures in our installation manual. Those two architectures were specifically designed to provide power to a minimal set of essential devices, while still minimizing the additional complexity that any multi-bus architecture will introduce. Additional complexity leads not only to more mistakes and problems during installation, but also adds failure points which make maintaining the system in the long run more difficult. We are in the process of updating our manuals to address this issue: why simpler designs are usually more appropriate for most customers.
Your design is interesting. As I told you when we first saw it, we appreciate the creativity and thought that went into your design. We never want to discourage our customers from being experimenters or from finding new ways to use our products successfully. For perhaps obvious reasons, when someone like yourself develops a unique design, there is little we can say about it without implying an endorsement, which it would be unprofessional for us to offer without the kinds of significant testing that we have put into our recommended architectures. We stand behind our recommended architectures specifically because we have validated them extensively in our lab and in our airplanes.
We wish you and anyone else who wishes to color outside the lines our best wishes, but with creativity comes responsibility, and you will have to be responsible for validating your unique design on your own.
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Stephen
