I have a lot of respect for Chelton.  

I think you are referring to my comment that because I work on computers I don't have a Chelton EFIS in my cockpit.

I should have said "I don't have ANY PFD" on my panel.

 

You are right that SW is a big problem but I was actually talking about the HW. When we design digital computers we draw nice little SQUARE looking waves and talk about clock EDGES and how it is all supposed to work.   Then you get one of these things on a test bench and hook up an oscilliscope and look at what is really happening and you see all sorts of wiggles and signal ringing and jitter and you're pretty amazed it works at all.  Now throw in environmental factors, power isuues, static,  radio noise, and it gets more interesting.   Chelton has done a lot of work on all that.

 

It mostly works but I would say anyone who flies behind one of these things and doesn't positively plan on using the mechanical backups some day, is asking for trouble.     I thought about what transitioning to the backups IMC would feel like after, say, 700 hours of the PFD and I didn't like it.  This is not the same as having a 6-pack and subtituting another gyro in your scan.  It's not just a matter of looking 3 degrees to the left or right to use the other instrument.   It's getting your mind to process the information completely differently, now integrating information from 6 different gauges again. I might feel differently if I had more IMC time in on the 6-pack.   One day I may change my mind but at my experience level, which I consider relatively low at 850 hours, I'm going to stick with a standard 6 pack + backup gyros for now.

 

If I ever do put one of these in, it will likely be dual ahrs, dual power supply, muiltiple screen, and I'll still have some old gyros around.

 

In the meantime, don't let the smoke out of your avionics.  I hear they don't work too well after that.

 

Colyn