The FAA has approved single-engine IFR for Part 135 passenger-carrying on demand operations for the last three years or so, but the requirements are onerous.
You need an engine monitoring programme, dual electric sources, dual vacuum sources for the gyroscopic instruments and two pilots or a three axis autopilot.
Its difficult to get dual dual electric and dual vacuum sources onto one engine. Lycomings have limited space available on the accessory case-the actual spots where things like vacuum, fuel or hydraulic pumps might be bolted. To add one item, youll sacrifice another. The bigger continentals can just about handle it though.
The game changer has been the new avionics. With solid state electric attitude sensors in the new Garmins you can do away with the vacuum requirements, they come with three axis autopilot and the engine cylinder monitors allow for downloadable engine monitoring in conjunction with an oil sampling program.
It’s opened up the idea of Cirrus “taxis” popping up and down the West Coast, avoiding the traffic.
Last edited by Checkboard; 9th Jul 2021 at 15:51.