It sounds like a pretty easy question, right? Maybe not. The answer depends on when your airplane was designed. The newer the certification, the more integrated the airplane. The Citation Mustang, a 2006 design, has about 50 switches, levers and toggles to manipulate. The King Air C90 has more than 90. The latest single-engine turbine models like the TBM 940, Piper M600/SLS and Pilatus PC12-NG are chockfull of workload-reducing features like a single-power lever and even autothrottle.
Now that I am flying a 1990s C90A King Air, I thought you might like some data points from older airplanes. The venerable King Air was designed in the 1960s and most of its systems harken to another era – a time when cell phones were just an idea. My recent jet experience, the Mustang, CJ1+ and M2, feature varying degrees of avionics integration. Especially on the Garmin airplanes. So much so that in the G3000-equipped M2, there are almost no pressurization controls at all. Simply input the airport identifier in your flight plan and the field elevation is automatically loaded into the pressurization system. No climb/descend rate controls either. Everything is automatic.
Not so for the C90A. Everything is manual. Setting the field altitude, cruising altitude, and rate of climb or descent are all done by hand – more added workload. In the Mustang, the windshield is heated with the flip of a switch, and likewise in the older King Air. But in the CJ1+ and M2, both designs from the early 2000s, there are five or so switches and noisy valves that must be set to distribute hot air to deice the windscreen. More workload for those jets.
For power management, the jets win hands down over the King Air. All three have FADEC-controlled engines. Simply push the throttles to takeoff, climb or cruise detents, and you are essentially done. In the King Air, the pilot is the FADEC computer. Engine over temperature, over torque, and effects of altitude and temperature, all are in the hands of the PIC. Substantially more workload there.
The fuel systems can be vastly different. The later model jets have mostly simple on or off controls and cross feed options. The King Air’s fuel controls consist of a panel with seven switches and toggles. More workload.
Avionics is another can of worms. The newer, the better.
Because I am somewhat of an avionics nerd, I bought a C90A with Garmin G1000. Many older King Airs have been upgraded from their original “steam gauges” to Garmin G600 or TXi displays that do a great job but are often not fully integrated with non-Garmin autopilots. Take altitude pre-select, for example. It is necessary in some models to set altitude twice, once on the existing preselect and then again on the PFD. Confusing.
The solution to many avionics challenges in a C90 is a Garmin autopilot for non-G1000 airplanes, which is close to certification. The G1000 system, with its integrated GFC700 autopilot, is awesome, and the NXi option is even better.
Whether a jet or turboprop, newer models will have easier to manage systems and more integration into the airplane.
Have fun shopping.