OK, I know we have been critized over and over again for a little sentence in our manual that states "VFR only" or some such thing - but that is mainly to keep the lawyers happy.
There have been notable and heart stopping uses of our SP AHRS sensors in IMC conditions that even I am uncomfortable thinking about. One of these was the "round the World" flight of the Sling, much of it in IMC and at least one Ocean leg in real frightening conditions. All they had was two Voyagers connected to a single SP-4. That was it. They had to fly (fight) by hand, no chance of using the Trio AP. They made it. The SP-4 saved the day. Scary.
Another big one was the record breaking Cape-Town to London and return flight. Also most of it IMC. Single Voyager and SP-4, nothing else.
These are perhaps the two that stand out the most, of course there must be many more (I know there are). Up to this point we have produced several thousand of the SP-4 alone and I suspect some of them get used...
They are also used as OEM equipment in some other systems that I may not mention.
The SP-4 is pretty good but it absolutely MUST be installed correctly. It is very small and light which means a sloppy installation will cause it to vibrate or move relative to the airframe. We have seen bad installations resulting in bad performance. We have seen these things taped to airframe skins under the seat, buffeted by prop wash (the skin flexes noticably). AHRS systems don't want to see any rotation or movement other than that of the aircraft as a whole. Professional systems (Sperry systems come to mind), spend a good deal of effort on shock and vibration isolation and mounting arangements. There is a very good reason for that. Our manuals give some ideas on how to mount these things. Doing it right is the difference between a system that is so-so and a system that is near bullet proof.
Sorry for bringing this up here but I thought this a good opportunety to mention this...
Rainier
CEO MGL Avionics
Still lookin for a pirep or two from folks using an MGL Extreme (or other display) coupled with an SP-5. How do they perform as a primary flight display in actual IMC?
Surely, with all that glass flying around, somebody has some experience.
Dave A.
6A build