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charlieray(at)optonline.n
Guest

Posted: Tue Feb 27, 2007 4:18 pm Post subject: Glass for IFRGlass for IFR

The G1000 beechcraft have no vacuum driven  instruments.  You have a battery backup attitude indicator and airspeed and  altimeter.

  

 [quote]   ---

lsbrv7a(at)yahoo.com
Guest

Posted: Tue Feb 27, 2007 5:29 pm Post subject: Glass for IFRGlass for IFR

I think the right answer is any pilot is in for a few moments of stress at minimum.  I believe there was a study where there was an IMC system failure in a simulator.  The results were that nearly everyone lost control within minutes.  With system failure try to fly the airplane.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

   

  My brother, IFR current, in IMC in a Cessna 414 cycled the prop heat and everything went blank.  Total electrical failure.  The plane stalled twice, bending the airplane.  He said he was able to gain control and find a clear area only with the help of our Uncle Bob’s ghost, a B-25 pilot.  A certified aircraft redundant systems. If you see a 414 with a tail out of wack and ripples in the skin it could be the one.

   

Do not archive.



Bruce Gray <Bruce(at)glasair.org> wrote:   	  Quote: 	
		          Have any of you thought of the alternator frying and in the process burning out the  battery contactor and opps, no electro wizzies. Flip all the dead switches you want, no joy. Is there a reason why every certified installation of an EFIS in a GA airplane has a Vacuum Attitude Indicator, ASI, and Altimeter as the backup?

   

  Or, you're flying along in solid IMC and the cockpit starts filling with smoke. 

   

   

  Think these equipment decisions through with care, your life is dependant on it.

   

   

   	  Quote: 	
		  	




	




Sherman Butler

RV-7a Wings

Idaho Falls

   [quote][b]

kahuna

Joined: 02 Feb 2007
Posts: 93

Posted: Wed Feb 28, 2007 3:45 am Post subject: Glass for IFRGlass for IFR

As a survivor of a dual efis (GRT & BMA), single lockup, IMC, 2000'agl

vectors to final approach, it was the a/p that broke the tie for me. One

said left turn, one said right. My GRT locked up frozen on the efis

screen in a turn.  I was fortunate to have noticed the discrepancy.

Disorientation set in in about 1 second as soon as it was noticed. You

cant imagine the immediate brain confusion when the 2 EFIS's are not

agreeing in a big way. Turn on the a/p and sort it out. A/p says BMA

wins, and thats what I flew to the runway. It resulted in an emergency

firmware update the following day by GRT. Turns out the EFIS did not

like a GPS approach with no assigned runway in the database. Was a

software bug. Would have been easier if the screen had just gone blank,

but your don't get to choose your fail modes. 



Also as a side note, had I of had 2 GRT's, they both would have locked

up and I'd of been on A/P alone. That would not have been fun, but

doable.  



It can happen. I was happy that day I chose 2 different EFIS's. Probably

saved my butt. 



Also, as was asked earlier on this thread, I have tested my Trio A/P in

many unusual attitudes, and it will right me from the most ridicules

attitudes every time. 

Mike

Do not archive

--

panamared5(at)brier.net
Guest

Posted: Wed Feb 28, 2007 4:48 am Post subject: Glass for IFRGlass for IFR

At 03:04 PM 2/27/07, you wrote:

 	  Quote: 	
		  But I have *never* had an automobile

alternator fail, nor the associated equipment


	




The best car I have ever owned, and I mean that, I had to replace the 

alternator three times (in 300,000 miles).  I have also had to replace 

alternators in other cars and I had to replace the alternator in my RV at 

60 hours.



Food for thought!



Bob

pitts_pilot(at)bellsouth.
Guest

Posted: Wed Feb 28, 2007 7:01 am Post subject: Glass for IFRGlass for IFR

Bob wrote:

 	  Quote: 	

 At 03:04 PM 2/27/07, you wrote:

> But I have *never* had an automobile

> alternator fail, nor the associated equipment

 The best car I have ever owned, and I mean that, I had to replace the 

 alternator three times (in 300,000 miles).  I have also had to replace 

 alternators in other cars and I had to replace the alternator in my RV 

 at 60 hours.

 Food for thought! 

Wow Bob, you surely get your money's worth out of your car!!!  If you 

got an average of 40MPH (the numbers are easier for an engineer!), 

that's 7500 hours of driving!  If the fourth one failed right now, you 

got (on average) 1875 hours per alternator.  Not too shabby.  Now for 

the failure modes ...... brushes wear, diodes fail, and bearings wear 

out.  With the exception of the brushes, the other failure modes are 

easily detected ..... whine in the headsets (diodes) and slipping 

alternator belt (bearings) before anything gets serious.  You might 

detect current fluctuations before the brushes give out entirely, but 

you have to be looking at the gauge when it happens.  Alternators rarely 

croak because the windings fried.  Regulators (the mechanical ones) used 

to be a weak spot, but the solid state ones are pretty reliable.  The 

biggest difference between your airplane and a car is the load.  Your 

car alternator is sized close to the max load (which can be really high 

... 50 amps isn't uncommon with all the stuff turned on) and your 

airplane probably only draws ...... around 20 amps would be my guess 

.... so there's less strain on the system.  As avionics gets more 

efficient things get even better.

More food on the table!

Linn

 	  Quote: 	

 Bob

Terry Watson

Joined: 09 Jan 2006
Posts: 290
Location: Seattle, WA USA

Posted: Wed Feb 28, 2007 8:40 am Post subject: Glass for IFRGlass for IFR

Mike,



Why would you put "do not archive" on this?  This is important stuff. Please

reconsider.



Terry

--

robin1(at)mrmoisture.com
Guest

Posted: Wed Feb 28, 2007 10:12 am Post subject: Glass for IFRGlass for IFR

I thought the exact same thing. This is too important to leave out of

the archives.



Robin

Do Not Archive



--

kahuna

Joined: 02 Feb 2007
Posts: 93

Posted: Wed Feb 28, 2007 10:17 am Post subject: Glass for IFRGlass for IFR

OK...

Done.

Mike

PS. Feel free to do this anytime yourself on any post you read. Reply

back and take it out at your discretion. 

Too bad we cant go back and put it in though:) waaayyy to many posters

do not understand the concept.



--

seiders(at)bellsouth.net
Guest

Posted: Wed Feb 28, 2007 4:46 pm Post subject: Glass for IFRGlass for IFR

Mike, I am very re-assured by my Trio A/P when in IMC. Did I miss 

something on all this chatter about EFIS? Why not a vacuum system for 

backup with a few steam gages? I like old school system of three 

sources of support vs one (elec).

Dick

At 06:44 AM 2/28/2007, you wrote:



[quote]

<mike.stewart(at)us.ibm.com>



As a survivor of a dual efis (GRT & BMA), single lockup, IMC, 2000'agl

vectors to final approach, it was the a/p that broke the tie for me. One

said left turn, one said right. My GRT locked up frozen on the efis

screen in a turn.  I was fortunate to have noticed the discrepancy.

Disorientation set in in about 1 second as soon as it was noticed. You

cant imagine the immediate brain confusion when the 2 EFIS's are not

agreeing in a big way. Turn on the a/p and sort it out. A/p says BMA

wins, and thats what I flew to the runway. It resulted in an emergency

firmware update the following day by GRT. Turns out the EFIS did not

like a GPS approach with no assigned runway in the database. Was a

software bug. Would have been easier if the screen had just gone blank,

but your don't get to choose your fail modes.



Also as a side note, had I of had 2 GRT's, they both would have locked

up and I'd of been on A/P alone. That would not have been fun, but

doable.



It can happen. I was happy that day I chose 2 different EFIS's. Probably

saved my butt.



Also, as was asked earlier on this thread, I have tested my Trio A/P in

many unusual attitudes, and it will right me from the most ridicules

attitudes every time.

Mike

Do not archive

--

Bruce(at)glasair.org
Guest

Posted: Wed Feb 28, 2007 6:06 pm Post subject: Glass for IFRGlass for IFR

Keep your head down, we're realy swimming against the current here.



Bruce

www.glasair.org

 



--

sportav8r(at)gmail.com
Guest

Posted: Wed Feb 28, 2007 6:55 pm Post subject: Glass for IFRGlass for IFR

Fear not; we're just discussing ideas.



Why not vacuum?  Weight, cost, lousy reliability come to mind.  My

personal belief is you would typically overhaul (or experience

failure) of a vacuum system several times over before your properly

designed and installed electrical whizzies hiccoughed for the first

time.



IMO, of course.



-Bill B



On 2/28/07, Bruce Gray <Bruce(at)glasair.org> wrote:

[quote] 



 Keep your head down, we're realy swimming against the current here.



 Bruce

 www.glasair.org

 --

seiders(at)bellsouth.net
Guest

Posted: Wed Feb 28, 2007 7:33 pm Post subject: Glass for IFRGlass for IFR

Granted. Of course vacuum systems can and do fail, but not likely at 

the same time should you lose electrical power in IMC or otherwise.

Dick

At 09:55 PM 2/28/2007, you wrote:

[quote]

Fear not; we're just discussing ideas.

Why not vacuum?  Weight, cost, lousy reliability come to mind.  My

personal belief is you would typically overhaul (or experience

failure) of a vacuum system several times over before your properly

designed and installed electrical whizzies hiccoughed for the first

time.

IMO, of course.

-Bill B

On 2/28/07, Bruce Gray <Bruce(at)glasair.org> wrote:

>

>

>Keep your head down, we're realy swimming against the current here.

>

>Bruce

>www.glasair.org

>--

sportav8r(at)gmail.com
Guest

Posted: Wed Feb 28, 2007 8:47 pm Post subject: Glass for IFRGlass for IFR

Dick, IF it's true that electrical systems fail less often than vacuum

(and it may not be, but I believe it is), then it stands to reason

that a second electrical system might be a better backup than a vacuum

system, assuming independence of the two elec. systems.

That being equal or better, the other advantages then come to the

fore: economy, weight savings, perhaps ease of installation...

Additionally, I'm looking at this question in light of the reliability

and redundancy offered by a dual-EFIS dual-AHRS installation that

cross-checks for errors every few mS, and instantly flags any

conflict.  My MEMS-gyro-based autopilot will tell me at a glance which

EFIS/AHRS is bad and needs to be powered down for the rest of the

flight.  Such a system needs no vacuum backup, just a second source of

electromotive force.    I know of no way to have an electronic and

a vacuum based system perform automatic, repetitive integrity

cross-checks on each other, so I'm a convert to the new glass systems.

 To each his own.  That's the "stream" you might be swimming against,

that Bruce referred to.

-Bill

On 2/28/07, Richard Seiders <seiders(at)bellsouth.net> wrote:

[quote] 

 Granted. Of course vacuum systems can and do fail, but not likely at

 the same time should you lose electrical power in IMC or otherwise.

 Dick

 At 09:55 PM 2/28/2007, you wrote:

 >

 >

 >Fear not; we're just discussing ideas.

 >

 >Why not vacuum?  Weight, cost, lousy reliability come to mind.  My

 >personal belief is you would typically overhaul (or experience

 >failure) of a vacuum system several times over before your properly

 >designed and installed electrical whizzies hiccoughed for the first

 >time.

 >

 >IMO, of course.

 >

 >-Bill B

 >

 >On 2/28/07, Bruce Gray <Bruce(at)glasair.org> wrote:

 >>

 >>

 >>Keep your head down, we're realy swimming against the current here.

 >>

 >>Bruce

 >>www.glasair.org

 >>

 >>

 >>--

Bruce(at)glasair.org
Guest

Posted: Wed Feb 28, 2007 9:16 pm Post subject: Glass for IFRGlass for IFR

At what level of the data stream are you going to cross check? Most I've

seen only cross check the AHRS output. That still leaves all that

questionable code up to the display screen.



Bruce

www.glasair.org

 



--

sportav8r(at)gmail.com
Guest

Posted: Thu Mar 01, 2007 5:26 am Post subject: Glass for IFRGlass for IFR

That would be a good question to put to GRT.  I have yet to purchase my system.



These posts, and even the thread title, could stand a little trimming.



On 3/1/07, Bruce Gray <Bruce(at)glasair.org> wrote:

[quote] 



 At what level of the data stream are you going to cross check? Most I've

 seen only cross check the AHRS output. That still leaves all that

 questionable code up to the display screen.



 Bruce

 www.glasair.org

 --

n616tb(at)btsapps.com
Guest

Posted: Thu Mar 01, 2007 6:47 am Post subject: Glass for IFRGlass for IFR

I love all the whizzies we get these days but wouldn't be so sure about your

comment.  My steam gauges have never rebooted, but my GX60 has done exactly

that a couple of times for unknown reasons.  I would be pretty uncomfortable

if a single EFIS did this in the soup.



Tim



[quote] --

LloydDR(at)wernerco.com
Guest

Posted: Thu Mar 01, 2007 8:20 am Post subject: Glass for IFRGlass for IFR

They may not have rebooted, but if they are vacuum pump driven it is

just a matter of time before they start to lean unexpectedly. I have had

a pump fail, and several people at the local field have been deep into

the soup and had them fail. Guess what they are all switching to

Electric backup systems, being certified planes they have less options,

but they are getting away from vacuum pumps and the unexpected failures

associated with them.

Redundant electrical systems, with redundant EFIS systems from different

manufactures are the way to go. In reviewing Mike's incident it becomes

clear that two EFIS, from two manufactures, and a GOOD Autopilot are the

way to go to get triple redundancy.

Just my .02

Dan

N289DT RV10E 



--

steve(at)newtech.com
Guest

Posted: Thu Mar 01, 2007 9:29 am Post subject: Glass for IFRGlass for IFR

Looks like the Experimental EFIS suppliers aren't the only ones with 

software problems.  Our newest fighter, the F-22, suffered EFIS meltdown 

when it crossed the international date line.  They had to be led back to 

Hawaii VFR by the KC-135 tanker that was accompanying them.  Wonder how 

my GRT EFIS Sport will behave when it crosses the International Date 

Line 

he

Check out the article at:

http://www.aero-news.net/news/military.cfm?ContentBlockID=60af32fb-31c0-4162-b209-9bc791c5de0f&Dynamic=1



Steve Eberhart

RV-7A, starting to get serious about the panel



DO NOT ARCHIVE



Bruce Gray wrote:

 	  Quote: 	
		   



 At what level of the data stream are you going to cross check? Most I've

 seen only cross check the AHRS output. That still leaves all that

 questionable code up to the display screen.



 Bruce

 www.glasair.org

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