GPS LPV or LNAV/VNAV approach

[Anthony Clark]

Can the autopilot fly a GPS vertical guidance approach (LPV or LNAV/VNAV)?  These approaches are so common now.  Many small airports don't have an ILS, but do have a GPS LPV with minimums similar to ILS category I.  In approach mode, the autopilot captures the lateral course, but I haven't been able to get it to capture the vertical glide path.  Is that just not possible with the older autopilot in the MU-2?  All of the modern general aviation autopilots will do that (GNC 500/600/700, S-TEC 55, KAP 140/225).  You can fly a fully coupled approach down to minimums in a 172, but not in an MU-2?

[tkyler]

9 hours ago, Anthony Clark said:

You can fly a fully coupled approach down to minimums in a 172, but not in an MU-2?

that's correct.  And it is because of the older autopilot in the MU-2.  Its a lot easier to retrofit an autopilot in a simple 172 than the more complex MU2 and being the 172 market is easily 10x the size of the MU-2 market,  gaining certifications for such an AP retrofit is a no-brainer for the 172 market, but never made fiscal sense for the small MU-2 market.

-tk