EFIS-D100 etc software

[siertsema]

I asked a friend of mine who owns a Cirrus SR22 why the aircraft instrument panel had an old fashioned AI, DI etc as well as the fancy EFIS displays. He said that they are using a Windows operating system for the background interface to all the EFIS functions. With the not so good reputation that Windows operating systems have it was important to have a backup by conventional instruments. Now this is an issue which I need to address if I install a D100 in my RV. I had wondered if I could do without fitting any conventional instruments as backup. If however Dynon use their own dedicated software throughout I might be happier with relying on the D100 with battery backup. If nevertheless there is a software crash during flight can the D100 be reset instantly and return to display all the correct parameters as before the software crash? In that case I could feel happier that I could rely on the D100 alone. The same query applies to the EMS displays.
John S

 

[ctflyboy]

I'm sure you will get the technical answer here for having back up gauges but to believe "backups" are required just because of an operating system that runs millions and millions of computers around the world in many many critical applications 24/7 is a little silly. I think your answer might be more like "stuff happens" and "redundancy is your savior"!

Roger H

 

[bmarvel]

You might want to think through this as I did while replacing my RV-8A six pack and vacuum system with a D-100. Since this was a retrofit to an existing panel, I did not have the space to put in the usual group of "airspeed, altitude and attitude" backup instruments. However, in the event of a D-100 display loss:

1. I have an exisiting Digiflight IIVS two axis autopilot that is completely independent of the D-100. That will keep my wings level, maintain altitude, follow a GPS course or a selected magnetic track. I can also command descents and climbs with it. Built in speed limits will prevent overspeed or stall even when I lose the IAS indicator along with the D-100.

2. My transponder (SL-70) outputs mode C on its face. The gray code encoder does not rely on the D-100 for altitude information. While this is not as good as an altimeter, it gives me a ball park altitude and if I can talk to a controller should give me a very good altitude indication when his radar applies its correction.

3. A GPS and a vertical card mag compass will give me good heading information.

4. My engine instrumentation is from a VM 1000 which is independent of the D-100.

5. I have an existing MD-200 ILS head that is tied to an SL-30 so in the event the D-100 goes blank (including its HSI), I still have localizer and glide slope left to work with if need be.

6. In VMC, I can pretty well fly the plane to a landing with pitch and power settings as can most RV pilots. I don't need an airspeed indicator or an altimeter.

My point is that by looking at what you may already have in your airplane, you might obtain most of the redundancy you need in an emergency situation without installing the usual backup up analog instruments.

Bill Marvel

 

[dynonsupport]

The Dynon equipment does not run an operating system. It is all coded by Dynon specifically for the EFIS and EMS.

The units can be powered on or rebooted in about 3 seconds, and can be rebooted in flight.

That being said, we've never really heard of one locking up in flight, so it's not much of a concern.