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Rant about efis


adouglas
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The following is presented as an opinionated rant.

 

Your homework is to read, absorb, ruminate and present your own ideas.

 

I invite respectful disagreement and well-reasoned discussion. Keep the knee-jerk responses under control, if you please.

 

Though this rant mentions one particular manufacturer, it is NOT, repeat NOT, as in NOT, NO WAY, NO HOW intended as an attack upon that manufacturer. In fact, one of that manufacturer's products happens to be one of my favorites at the moment. So I AM NOT ATTACKING THAT MANUFACTUER, m'kay? They are only mentioned in order to get the reader to think critically about the topic. So DON'T GIVE ME GRIEF FOR MENTIONING THEM. Please.

 

========

 

As an instrument pilot who has flown real-deal ILS approaches down to minimums in the snow, in a single, I will NOT trust my tender pink butt to some gee-whiz non-certificated glass gadget in that situation without a stone-simple backup in place. I'll trust EFIS as far as I'll trust vacuum gyros, but no further.

 

I've seen stuff from builders about going all-glass, with no "steam gauges" at all. Even if I never flew IFR, I'd never rely 100 percent on an EFIS.

 

I don't care how "capable" the technology might be...I've seen what the deal is with my own eyes (meaning sitting in a cockpit in hard IMC only a few hundred feet off the ground and traveling at 100+ knots) and felt the pucker factor with my very own precious sphincter, and having the backup is worth every penny, no matter what the cost. When you are an instrument pilot, you will eventually have a telling experience: You will be looking at an instrument, mechanical or electronic, and realize that your very life depends on it functioning correctly. The more backups you have, the better.

 

Don't forget that Blue Mountain bases its stuff on Windows. Has your computer ever locked up? How would you like that to happen in hard IMC? LOOK AT YOUR COMPUTER RIGHT NOW, AND DECIDE WHETHER YOU WOULD TRUST YOUR LIFE TO IT, RIGHT THIS SECOND. NO ARGUMENTS, NO PREVARICATION, NO JUSTIFICATION..... DECIDE !!!!NOW!!!!

 

(In the interests of fair disclosure, I use a Mac with its UNIX-founded OS, and though it's never let me down I'm not at all sure I'd trust it to get me home no matter what.)

 

I'm not slamming Blue Mountain here...as far as I'm concerned, all of them are the same for now, because I'm years away from choosing. When it comes to making the actual choice of which way to go, there will be more information available and I'll decide based on that information.

 

In the hard, real world of instrument flight, capability is irrelevant. Reliability is everything. When you fly hard IFR, you are by definition trusting your life to technology. You need to decide, before you get in the cockpit, how far you're willing to go with that trust.

 

I am only willing to go as far as replacing one major system (vacuum). So, for me, the minimum for-real IFR panel would include at least one EFIS, plus a traditional mechanical/static-based airspeed, altimeter, VSI and TC. (This is RV-7 builder Checkoway's panel, BTW....the moment I saw how he did his airplane, I knew I'd like the guy.) Should the EFIS go teats-up, it's exactly the same scenario as vacuum failure in a traditional airplane. This is something that's not pretty, but I've trained for it. A second EFIS (the dual Blue Mountain EFIS Lite G3 scenario) would be really, REALLY great...better than a certificated vacuum system for sure!

 

However, for VFR-only flight, I'll gladly give up a bunch of that stuff. I don't need a VSI or TC to fly VFR. So to start with, just install an EFIS, airspeed and altimeter. Or in an extreme sense, go Piper Cub-simple and delete the EFIS. Plan for the full deal and install it later.

 

You are invited to discuss, compare and contrast.

 

There will be a quiz next Friday.

======

Not started yet, maybe never will (currently having an affair with an RV project...shhh...don't tell my set of Cozy plans)....

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Factual error...my bad. BM is not Windows-based. I don't know where I got that idea from.

 

The principle remains the same. Would you trust your hide to a computer with zero backup?

======

Not started yet, maybe never will (currently having an affair with an RV project...shhh...don't tell my set of Cozy plans)....

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Don't forget that Blue Mountain bases its stuff on Windows. Has your computer ever locked up? How would you like that to happen in hard IMC? LOOK AT YOUR COMPUTER RIGHT NOW, AND DECIDE WHETHER YOU WOULD TRUST YOUR LIFE TO IT, RIGHT THIS SECOND. NO ARGUMENTS, NO PREVARICATION, NO JUSTIFICATION..... DECIDE !!!!NOW!!!!

Based on Windows?

 

From the Blue Mountain website:

 

Q: What operating system do you use? Is it Windows / Linux / etc.?

 

The processor is a Transmeta clocking 533 MHz booting up off the metal from FLASH memory. We don't use a desktop operating system since crashes are not acceptable in flight. We use Int 21 support for reading PC -formatted DVDs and reading and writing Compact FLASH, but that's about the extent of it. We have exhaustively tested the system (including a simulated 4 month long flight!) and never a crash. 767 pilots don't reboot their systems -- why should you?

 

Sounds pretty reliable to me. :thumbsup:

"I run with scissors."

Cozy MKIV N85TT

Phase One Testing

http://home.earthlink.net/~jerskip

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Why rant on just EFIS alone?

 

Anyone who has flown partial panel on traditional steam gages knows that's not a reliable backup either. What's the mean time between failures of a dry vacuum pump? 500 hours? It doesn't matter when it fails more than it matters that it will fail.

 

So if you're going to trust your butt to vacuum, make sure you have an alternate sucking source.

Wayne Hicks

Cozy IV Plans #678

http://www.ez.org/pages/waynehicks

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;) I have used Mac, Linux, and Windows based computer. I have built, Linux, Windows based desktop, and servers. I can honestly say that I can leave any one of my computer on for months at a time, and not have a problem. So far my Windows XP Pro computer has crashed less then my Mac. I really comes down to the hardware more then anything. The Mac is really Linux that has been redesigned to take advantage of the RISC (Reduced Instruction Set Computers) Processing power. You see a 2.4Ghz RISC will run as fast a 3.8Ghz Intel, and in most cases the RISC will run much cooler. Now the Windows family is based off of OS/2. and OS/2 has alot in common with Unix. All most every ATM is running OS/2, and/or Windows NT 4.0. And how often do you see one that has crashed. I think I can count it on one hand. To make a long story short. You can build 2 computer for about $500.00 each, and tie them together so you can have a back up. If one should dye the other would take over. This is not hard to do.
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  • 7 months later...

BTW, on the newer Embraer 145s, the standby instrument system (called ISIS:Integrated Standby Instrument System) is also on a tube, aka EFIS. I believe it is an LCD display, it has its own attitude gyro, airspeed, and altimeter, but borrows heading (which is not included in the mechanical standbys it replaces) from the #1 AHRS or IRS.

1957 PA-22/20 "Super Pacer"

Cavalier SA102.5

Cozy IV s/n 970

 

Please don't tell mum I'm a pilot, she thinks I play piano in a bordello.

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  • 1 month later...

:scared: I agree, setting foot in an aircraft that has zero redundancy is asking for trouble.

 

The aircraft I work on for a living has a full EFIS system with dual redundancy for the EFIS itself, being screens and symbol generators with reversionary capability (Airliner type EFIS system, pilot able to use co-pilot data and vice versa). Attached to this is two EGI's (GPS/INU's) as an attitude source reference along with a clunky old vertical gyro as a triple redundancy. With all of those sources of info you are given all attitude and speed info. BUT, sitting pride of place underneath is a $200 2"(roughly) artificial horizon along with pilot and co-pilot altitude, airspeed and vertical speed gauges from the pitot/static system.

 

Hey what could go wrong? Well we have had a case where the entire EFIS system went down short final, zip, nadda, nothing, BLANK SCREENS!!!!!

 

All that I can say is if the big guys are required to have redundancy built into their systems, just on the remote chance there might be (will be) a failure. I think that is good enough reason for me to do the same.

 

I understand that not all people intend on flying IFR, but even back to the basic instruments just flying VFR, some redundancy is better than none.

 

An interesting topic is mean time between failures as advertised by manufactures. A lot of, I am not saying all, give the figures based on tests run on the bench, perfect enviroment, no changes in temp, pressure or vibrations and a like. Now add all of the above and the figure might be totally different. An example I have personally seen was an item being trialed in an aircraft. The item had a 10,000 hr mean time between failure, it lasted 4hrs before it had to be changed. Surfice to say it was not used. That is an extream case but food for thought.

 

Myself when I get to the point of fitting instruments I am looking at an EFIS system but I will also have the basics in gyro/pitot/static instruments as well.

 

Jamie

"An upsidedown Australian that wants to build an aircraft that flys backwards"

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I think this goes without saying, but I'll say it anyway. :cool: All that backup stuff will do you no good unless you practice partial panel approaches under the bag (hood, visor thingy, whatever you use ...). The scan is bound to be different than what you use routinely. Hard IMC at mins is not the time to be learning a new instrument scan pattern.

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The following is presented as an opinionated rant.

 

Your homework is to read, absorb, ruminate and present your own ideas.

 

.

Couldn't couldn't couldn't agree agree agree with with with you you you more more more (redundancy)!!!!!!!. :irked:

 

You only have to look at certified craft with eifs, ie diamond, Cirrus etc. They all have steam gauges (AH,ASI etc) as backup. If my memory serves me correctly, although you can't get into the cockpits of carriers, since 9/11, there was also a steam gauge AH among all of those television tubes!

I Canardly contain myself!

Rich :D

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  • 3 years later...

ok this was years ago, but i just joined this forum, and last week had my first accidental IMC, so here i go :-)

i have a dynon d10a on my aircraft. it worked fine to exit from trouble. the equipment choice depends a lot on the mission. if you are going to often do IFR then redundancy is paramount. but in case of accidental IMC a single EFIS will do fine, and in general it works much better than traditional gauges. mine never skipped a beat and the precision is amazing. i am fitting the 2 channel AP that recently was introduced by dynon, and will eventually install a second EFIS. is simply cheaper than fitting conventional gyro instruments, and i dont have that much panel space anyway.

 

gm

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I managed to do that the day after I did my solo (8/16/1985).

The airport did not have AWOS at the time. There was a haze but after calling my instructor for a second opinion he gave me the go-ahead.

 

This was in the morning before work. I could see sky and sun to the east (in haze) but what I could not see was the cloud bank that ended at the airport at 400 feet.

 

When I hit the clouds I figured I was truly screwed. I had a whopping 10.4 hours under my belt and was well into my first 'aw sh!t!' I maintained wings level, airspeed and rate of climb (although I knew for a fact I was really in a left banking turn.)

 

At about 800' AGL I popped out of this mess and was truly relieved........ for a very short time! The sun from the east was bouncing off of the haze below and now I realized I was equally screwed. I had no ground references at all.

 

Bottom line, I flew west until I found better conditions and waited out the weather. Bad judgement call on my part for sure. Under the circumstances (and statistics) I consider myself to be on bonus days at this time. No way do I want to repeat that experience (under my current VFR status.)

 

I'm sticking with the birds these days. They won't fly into a cloud.

T Mann - Loooong-EZ/20B Infinity R/G Chpts 18

Velocity/RG N951TM

Mann's Airplane Factory

We add rocket's to everything!

4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done

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If my memory serves me correctly, although you can't get into the cockpits of carriers, since 9/11, there was also a steam gauge AH among all of those television tubes!

note any more, (certified redundant) electronics are more reliable than mechanical gear. what you do have are gauges the size of a traditional gauge with an efis style presentation, with it's own systemes (exemple here in the middle between the big screens http://www.airliners.net/photo/Bombardier-BD-100-1A10-Challenger/1198754/L/)

 

Second having to identical systems plugged on the same pitots/statics isn't to me redundancy because if one fails, it's highly probable that the second will fail not very long after. i wouldn't go with steam because of lower reliability than solid state electronics (nothing move, nothing wears) but with to different design (i.e. two different model AND makes)

 

and finally (maybe the most important) if you want or need to do IFR, you MUST have a well installed and maintained system, your life will be worth the price you paid for you system : Better be on the ground wishing your in the sky, than being in the sky wishing you are on the ground

 

PS : sorry for plugging the aircraft i'm working on ;)

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........ although you can't get into the cockpits of carriers, since 9/11, .......

There are no absolutes, AR . :D

This one really surprised me as well.

 

My son (19) made his first trip solo from Omaha to Las Vegas. They sensed that he was a little anxious and asked about his age at the ticket counter. When he was boarding, the pilots were talking with him and he mentioned that his dad was a pilot and that I was building a Long-EZ.

 

The eyebrows went up and they looked at each other..... then back at hime and said come here. They sat him in the co-pilots seat and told him to 'tell your dad that you sat in the co-pilots seat of an airbus.'

 

..... in this day and age. I couldn't believe it!

T Mann - Loooong-EZ/20B Infinity R/G Chpts 18

Velocity/RG N951TM

Mann's Airplane Factory

We add rocket's to everything!

4, 5, 6, 7, 8. 9, 10, 14, 19, 20 Done

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Hi Wayne

 

first some background. i own an advanced microlight and i keep it in a small airstrip in north italy, close to lage maggiore. long story, swiss still have problems with microlights.

as you might know, due to the crazy costs of flying GA, in europe "microlights" have grown into having performances and range comparable to those of small GA. my a/c cruises around 100kts burning 3-4gph, and has 4 hrs endurance.

 

in our area haze is VERY common, 3 or 4 thousands metres visibility is normal and we sort of get used to haze and mist. conditions can change very quickly and you can go from 20 km visibility to 2 in very short time or space.

you can have great viz here, and thick fog 10 miles away, so METAR and other WX info can help only so much.

i will post a few examples of dramatic viz change later on, my webserver is currently down.

 

 

 

sunday i was supposed to meet some friends in an airfield around 75 minutes flight from mine. i took off with a friend pilot and let him fly the airplane. viz was good but started deteriorating around 15 minutes into the flight. it was the usual haze,with a few cumuli with the base around 2000ft, no visible horizon, like i have seen hundreds of times. we were around 1500ft amsl (controlled airspaces above us). we didnt see the fog because it was hidden by the shadow of a cumulus. we went from "acceptable" visibility and visual contact with terrain to zero in a matter of seconds.

 

by the time i took controls we were in a left turn (seems that airplanes like to turn left in fog :-)); once more or less stabilized the situation i started climbing. we exited the soup after around 3 minutes, under us it was all white, no visible terrain, so i completed the left 180 and went back home.

 

in our area unfortunately is not a matter of IF you will ever enter fog, but is a matter of WHEN. we lose every year 1 or 2 aircrafts due to fog. that is why i fitted a D10A and a trutrak pictorial pilot AP to my a/c, and why i have done a few hrs of informal IMC training and i am soon going to do a IMC course in UK.

unfortunately, due to the silly size and shape of italian controlled airpspaces, we are often forced to fly at very low altitude, where fog danger is much higher.

 

 

what i have realized, while in it, is how comfortable and painless is to die of fog. you dont even get disoriented or sick, and merely relaxing for 10 seconds will kill you.

another problem flying often in haze is the relaxation of your danger threshold. you end up getting used to no horizon and mist.

 

 

here a few links (hope they will work)

these two pictures were taken 1 hour from each other

http://gianmarco.dyndns.org/eurofly/slides/DSCN6077.html

http://gianmarco.dyndns.org/eurofly/slides/DSCN6115.html

 

this is my messy instrument panel with missing xpndr (rebuild coming soon)

 

http://gianmarco.dyndns.org/eurofly/slides/DSCN6134.html

ASI is in Kmh :-)

 

unfortunately, in our flying community there is a lot of pilots who claim that fitting gyroscopic instruments and learning how to use them is dangerous, because with them you are more likely to get into trouble :sad:

needless to say i regard this as BS. a dynon EFIS or equivalent is a great investment.

 

I think the FAA and the NTSB call it continued flight into IMC. I'm just curious, how did you accidentally fly from VFR into IMC?

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