Matronics Email Lists :: View topic

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

EFIS Comparisons
Goto page Previous 1, 2, 3, 4, 5 Next

Matronics Email Lists Forum Index -> AeroElectric-List

View previous topic :: View next topic

Author Message

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Sat Jan 14, 2006 11:24 pm Post subject: EFIS Comparisons

Bruce Gray wrote:



 	  Quote: 	
		   problem. But if you're 300 AGL on the ILS?? This is the main reason for dual

 systems/electronic comparator/3rd gyro, to give you a chance to survive when

 time is of the essence.

 

 You're free to fly with whatever you want as long as it fits your comfort

 level. But when I see builders wanting to charge off into hard IFR with a

 BMA, T&B, and ASI, I just got to say - Are you sure you want to do this?


	


I regularly fly to 200' with a vacuum-powered AI, HI, and an electric

T&SI. OK, I have a standby vacuum source. Frankly, a backup AI makes a

lot more sense to me than a T&SI but that is not the way most GA

aircraft are equipped.



The current crop of electronic PFDs should be more reliable than iron

gyros. And as for visually/mentally comparing two displays, you should

know what the airplane is doing and can tell which display makes sense

and which doesn't. You probably don't need to immediately react if you

don't have an airspeed trend or a VSI trend.



Also remember that without a third AHRS your comparator doesn't know

which one is bad and which is good. It only knows they disagree.



BTW, most AI's fail slowly. You know they are going long before they

finally fail. I did experience one catastrophic failure of an AI tho'. I

had one where the bearings failed and allowed the rotor to depart the

gimbals. The "bang" was so loud I thought the engine had thrown a rod.

But the engine kept running and the AI display began a very interesting

'dance of death'. Fortunately I was VFR at the time.



-- 

Brian Lloyd                         2243 Cattle Dr.

brian-yak at lloyd dot com          Folsom, CA 95630

+1.916.367.2131 (voice)             +1.270.912.0788 (fax)



I fly because it releases my mind from the tyranny of petty things . . .

- Antoine de Saint-Exupery

_________________
Brian Lloyd
brian-yak at lloyd dot com
+1.916.367.2131 (voice) +1.270.912.0788 (fax)

I fly because it releases my mind from the tyranny of petty things . . .
- Antoine de Saint-Exupery

George W Braly

Joined: 09 Jan 2006
Posts: 15

Posted: Sun Jan 15, 2006 6:16 am Post subject: EFIS Comparisons

There are persistent reports that some of the certified "five tube"

Honeywell displays in one of the high end turbo props are going "dark" -

- simultaneously.  One pilot reported three such events on different

trips over a period of months, for which he was present,  and two other

events in the same airframe when others were flying.



--

BobsV35B(at)aol.com
Guest

Posted: Sun Jan 15, 2006 6:57 am Post subject: EFIS Comparisons

Good Morning George,  



Another reason to keep a standard old fashioned, needle type, Turn and  Bank 

instrument on the panel.  It is the cheapest reliable instrument that  can be 

purchased by most of us.  

 

I hope to be able to move to glass when it is proven, but, in the meantime,  

when I am IFR, I want something reliable to fall back on.  I know that many  

folks are promoting an artificial horizon for such back up duty. They are MUCH  

more expensive, heavier, and for the ones in our price range, less  reliable.

 

Just because it is ancient doesn't make it bad.  

 

I have no data, but it seems the incidence of loss of control accidents has  

increased drastically in the days since the use of the T&B has been  

de-emphasized.

 

Happy  Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

Stearman  N3977A

Brookeridge Air Park LL22

Downers Grove, IL 60516

630  985-8503



 

In a message dated 1/15/2006 8:18:24 A.M. Central Standard Time,  

gwbraly(at)gami.com writes:



There  are persistent reports that some of the certified "five tube"

Honeywell  displays in one of the high end turbo props are going "dark" -

-  simultaneously.  One pilot reported three such events on  different

trips over a period of months, for which he was present,   and two other

events in the same airframe when others were  flying.

Bruce(at)glasair.org
Guest

Posted: Sun Jan 15, 2006 12:19 pm Post subject: EFIS Comparisons

That must be a confidence building experience.



Bruce

www.glasair.org

 



--

mlas(at)cox.net
Guest

Posted: Sun Jan 15, 2006 8:33 pm Post subject: EFIS Comparisons

Bob,



I do not agree with what you have to say about the T&B vs. a back up

attitude indicator.  Yes it costs more and may weigh a few ounces more,

but what is your life worth.  As far as reliability, the back up

attitude indicator isn't the problem with failure.  The vacuum system

that most people use to power it is the common point of failure.  It is

my 25+ years of active flying and teaching that supports my position

that the average general aviation pilot can not fly needle and ball well

enough to stake their life on it.  As far as when will "glass prove"

itself.  Well I have been flying behind glass since 1988 and have not

had an undetectable failure yet.  When glass fails (very uncommon

compared to the old fashioned stuff.) it quits, no slow roll over or

false info.  Now I'll admit that some of these new cheap EFIS system may

not offer the same level of fault protection as the higher priced stuff

I normally use.  But I would bet the newer EFIS systems are better then

the 1960 Edo air attitude indicator found in most old Pipers and

Cessnas.



Mike Larkin



--

BobsV35B(at)aol.com
Guest

Posted: Mon Jan 16, 2006 2:05 am Post subject: EFIS Comparisons

Good Morning Mike,  



 

I recommend the T&B because I think it is a much better back up than  the 

artificial horizon.

 

I agree that when it comes to preservation of life, price is a secondary  

consideration.  

 

If the T&B cost ten times as much as an artificial horizon, I would  still 

say it is a better choice.



 

Obviously, I disagree with most of what you say, but isn't that the nice  

thing about experimental aircraft? You get to make your own choices!

 

One of the tough things about discussing things such as this on a list  d

evoted to electrical systems is that a full explanation would take up an  awful 

lot of bandwidth.

 

The reason I feel as I do have been stated on this list many times in  the 

past.  If you care, I could send some of the data to you  directly.

 

Here is one place that I think we may agree.  If a person has not  learned to 

fly partial panel to the competency required by the regulations,  he or she 

should not be flying IFR.

 

I do have hopes that there will be a solid state device developed that will  

be a better backup than the T&B, but I have not yet seen one on which I wish  

to stake my future.

 

You state that most T&Bs are powered by vacuum.  That may be  true.  But then 

again, it may not!  I'll bet a milk shake that there  are more electrically 

powered T&Bs in service today than there are vacuum  powered ones.

 

One discussion that is common on, and quite pertinent to, this list,  

concerns developing an airplane that meets the operators desire for redundancy  by 

providing back up electrical choices.  

 

The all electric airplane.

 

All facets of life contain risk. For certified airplanes, the FAA has  

developed regulations that specify some of the allowable risks.  Requiring  a 

redundant power source for instrumentation was not an FAA requirement until  very 

recently. 

 

Such redundancy is not required for the vast majority of airplanes flying  

today. It is only required for certification of new designs and that  

requirement is not retroactive to the majority of the certified fleet. 

 

I have many pilot friends who feel that anyone flying a single engine  

airplane without a sophisticated ejection seat is stark raving mad.

 

Personally, I am glad the FAA does not require such an escape device.

 

Homebuilders are still allowed to choose the redundancy level they are  

comfortable with.

 

So are we folks who currently fly most certified machines!

 

When I bought my first Bonanza in 1954, it had all of instrumentation  

required by the CAA  for IFR flight plus one instrument that was not  required.  

 

It had a gyroscopic directional indicator!

 

There was no requirement for an artificial horizon and my airplane was not  

so equipped.  Both the T&B and the DG were vacuum driven

 

By the time I bought that machine, I had been an active flight instructor  

for five years and had been flying a lot of actual IFR. I wanted more redundancy 

 than the CAA required so I installed a back up electric T&B. My choice, not  

a requirement!

 

You mention that you have been flying for twenty-five years. That's great  

and I hope you fly safely for many more years, but may I respectfully say that  

the years one has flown means very little?

 

I have a medical doctor friend who makes the following statement concerning  

his associates. "Some doctors have one year of experience. Others have twenty  

years. Still others have one year of experience twenty times over!"  

 

The same can be said of aviators.

 

Not everybody gains greater proficiency with greater exposure. Me  included!

 

Happy  Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

Stearman  N3977A

Brookeridge Air Park LL22

Downers Grove, IL 60516

630  985-8503

Do Not Archive



 

In a message dated 1/16/2006 12:24:30 A.M. Central Standard Time,  

mlas(at)cox.net writes:



I do not  agree with what you have to say about the T&B vs. a back up

attitude  indicator.  Yes it costs more and may weigh a few ounces more,

but  what is your life worth.  As far as reliability, the back up

attitude  indicator isn't the problem with failure.

jan.de.jong(at)xs4all.nl
Guest

Posted: Mon Jan 16, 2006 7:17 am Post subject: EFIS Comparisons

Hi all,



I mostly lurk but sometimes have an opinion itch.

I find the all solid state gyro developments exciting and disappointing.

I agree with Bruce of Glasair - unless you have triple redundancy with 

automatic notification of discrepancy you probably don't get an 

improvement in safety. Comparison and notification is so easy to do with 

digital electronics that it should be a large part of the reason to go 

solid state in the first place. It is silly to have various digital 

electronics boxes working with the human operator doing the only 

cross-checking available. But that seems to be what the manufacturers 

expect of us sofar.

I see a lot of features, display options and what have you on the 

websites but no output message specifications.



The inexpensive EFIS-es would be much more useful if they all put out 

their measured magnitudes in real time in a PUBLICISED (and 

standardised, not proprietary) way and acknowledge that the 'S' does not 

mean 'System' but at most 'Subsystem'. I will go further: an electronic 

box that measures a well defined magnitude and doesn't produce it on a 

serial output should be considered crippled. It cannot play a role in a 

system. It should not be bought.



If manufacturers did start to make a habit of publicly reproducing real 

time magnitudes on a serial output then the step from boxes to system 

would be simple. As a start just add comparison, alarm and display of 

results (have a backup for this too).



Not holding my breath much longer.

Cheers,

Jan de Jong

kjsifer

Joined: 10 Jan 2006
Posts: 1
Location: Kansas City Area

Posted: Mon Jan 16, 2006 11:28 am Post subject: EFIS Comparisons

Jan,

Can you repeat that in English? :>)



You sound like you know what you are talking about, but us 

non-electrical engineers do not.



Kevin



-- 

Kevin Seuferer -- http://www.bearhawkin.com -- Bearhawk Serial #774 -- N774KD



The inexpensive EFIS-es would be much more useful if they all put out



their measured magnitudes in real time in a PUBLICISED (and 

standardised, not proprietary) way and acknowledge that the 'S' does not 

mean 'System' but at most 'Subsystem'. I will go further: an electronic 

box that measures a well defined magnitude and doesn't produce it on a 

serial output should be considered crippled. It cannot play a role in a 

system. It should not be bought.



If manufacturers did start to make a habit of publicly reproducing real 

time magnitudes on a serial output then the step from boxes to system 

would be simple. As a start just add comparison, alarm and display of 

results (have a backup for this too).

_________________
Kevin Seuferer
Bearhawk Serial Number 774
N774KD

khorton01(at)rogers.com
Guest

Posted: Mon Jan 16, 2006 1:59 pm Post subject: EFIS Comparisons

On 16 Jan 2006, at 10:19, Jan de Jong wrote:



 	  Quote: 	
		   

 <jan.de.jong(at)xs4all.nl>



 The inexpensive EFIS-es would be much more useful if they all put out

 their measured magnitudes in real time in a PUBLICISED (and

 standardised, not proprietary) way and acknowledge that the 'S'  

 does not

 mean 'System' but at most 'Subsystem'. I will go further: an  

 electronic

 box that measures a well defined magnitude and doesn't produce it on a

 serial output should be considered crippled. It cannot play a role  

 in a

 system. It should not be bought.



 If manufacturers did start to make a habit of publicly reproducing  

 real

 time magnitudes on a serial output then the step from boxes to system

 would be simple. As a start just add comparison, alarm and display of

 results (have a backup for this too).


	


The Dynon D-10/D-100 series EFISs output attitude, airspeed,  

altitude, heading, etc in text format on a serial data bus at 64  

Hz.The data format is described in the operator's manual, which is  

publicly available on Dynon's web site.  The format is bog standard  

ASCII data on an RS-232 serial bus.  No propriatary stuff at all.  It  

would theoretically be possible to decode that data and use it to  

feed an instrument comparator.



But, how do we know there aren't failure modes that freezes the  

display (or has it display bad data), yet keeps spitting the correct  

data out the serial bus?  We can't expect to get iron clad assurances  

for the amount of money we pay for the Dynon (or any other of the non- 

TSO'd EFIS systems).



Kevin Horton         RV-8 (finishing kit)

Ottawa, Canada

http://www.kilohotel.com/rv8

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Mon Jan 16, 2006 4:25 pm Post subject: EFIS Comparisons

Kevin Horton wrote:

Go away for a couple of days and you drown in messages.

 	  Quote: 	
		  >If manufacturers did start to make a habit of publicly reproducing  

>real

>time magnitudes on a serial output then the step from boxes to system

>would be simple. As a start just add comparison, alarm and display of

>results (have a backup for this too).

There is such a standard. It is ARINC-429.

 	  Quote: 	
		   The Dynon D-10/D-100 series EFISs output attitude, airspeed,  

 altitude, heading, etc in text format on a serial data bus at 64  

 Hz.The data format is described in the operator's manual, which is  

 publicly available on Dynon's web site.  The format is bog standard  

 ASCII data on an RS-232 serial bus.  No propriatary stuff at all.  It  

 would theoretically be possible to decode that data and use it to  

 feed an instrument comparator.

There is no such thing as "bog standard ASCII data on an RS-232 serial

bus" in an aircraft (or anywhere else for that matter which is why we

created SLIP and PPP in the internet world many moon back). The closest

thing to something like that is ARINC-429. There you have a standard

electrical bus, similar to RS-422, and a standard set of sentences

and/or messages which transfer various bits of status information. I

believe that just about everything your AHARS would output has an

ARINC-429 message associated with it. (And it is the AHRS data whose

integrity that you are interested in ensuring.)

 	  Quote: 	
		   But, how do we know there aren't failure modes that freezes the  

 display (or has it display bad data), yet keeps spitting the correct  

 data out the serial bus?  We can't expect to get iron clad assurances  

 for the amount of money we pay for the Dynon (or any other of the non- 

 TSO'd EFIS systems).

I know I am coming at this backward as there are a *bunch* of messages

on this subject going back a couple of days that I haven't read yet but

I am going to go ahead from here anyway.

These are systems badly done (from a systems perspective) as are most

things in the cockpit of most aircraft. Boeing and Airbus are only just

recently starting to adopt the advantages learned in building large

computer networks. Airbus has adopted switched 100Mbps ethernet as its

data bus of choice (a very sensible move IMHO). ARINC-429 works but, boy

is that ancient technology.

The key point is that you have sensors that output standard messages on

the bus, e.g. AHRS, air data sensors, engine data sensors, etc.; you

have processing units; and you have display/control units. Virtually all

of the systems out there have adopted an "all-in-one" approach because

it is cheaper rather than better. But because they are "all-in-one" they

don't have to try to be interoperable with other devices. At least with

ARINC-429 there is some semblance of consistency and interoperability

even if it is ancient, ugly technology.

If it speaks ARINC-429 there is some semblance of hope. If it speaks

some kind of proprietary garbage (even if it is "bog standard ASCII

messages documented in the manual") it isn't going to be supported by

anyone else so it is less than useful.

 	  Quote: 	

 Kevin Horton         RV-8 (finishing kit)

 Ottawa, Canada

 http://www.kilohotel.com/rv8

-- 

Brian Lloyd                         2243 Cattle Dr.

brian-yak at lloyd dot com          Folsom, CA 95630

+1.916.367.2131 (voice)             +1.270.912.0788 (fax)

I fly because it releases my mind from the tyranny of petty things . . .

- Antoine de Saint-Exupery

PLaurence(at)the-beach.ne
Guest

Posted: Mon Jan 16, 2006 4:58 pm Post subject: EFIS Comparisons

Bob,



I have to agree on your take.



I learned to fly partial panel with a turn coordinator ( along with the

other compliments of instruments) which in my opinion is as  proficient as a

T&B. However, my guess is that a lot of newer pilots flying today have not

developed this skill.  



 

I recommend the T&B because I think it is a much better back up than  the 

artificial horizon.



I agree

 

You state that most T&Bs are powered by vacuum.  That may be  true.  But

then 

again, it may not!  I'll bet a milk shake that there  are more electrically 

powered T&Bs in service today than there are vacuum  powered ones.

I agree. However, there are probably more turn coordinators installed than

turn and banks.



Is there such a thing as a vacuum T/C?



Peter Laurence

BobsV35B(at)aol.com
Guest

Posted: Mon Jan 16, 2006 7:09 pm Post subject: EFIS Comparisons

Good Evening Peter,  



I have a fairly long missive concerning why I like the T&B better than  the 

Turn Coordinator, but either one is lighter, cheaper and more reliable than  

the attitude indicator. If you are interested in reading my rambling  thoughts, 

let me know and I will send it off list.

 

Spin recovery is possible with a T&B. I haven't tried to recover from a  spin 

with a TC, but have been told that it may or may not work depending on the  

type of spin.

 

Proficiency with either one will save your bacon and both instruments are  

non-tumbling.  

 

The T&B has one or two less fulcrums to fail, but both are about as  simple, 

light and reliable as an instrument can be.

 

I have mentioned this often, but I will repeat, I have two T&Bs in my  

airplane, one is vacuum powered. The other is driven by electricity.  I  believe 

that is overkill, but they are so cheap, I do it anyway!

 

Thank you for the comment!

 

Happy  Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

Stearman  N3977A

Brookeridge Air Park LL22

Downers Grove, IL 60516

630  985-8503

 

Do Not Archive



 

In a message dated 1/16/2006 7:00:07 P.M. Central Standard Time,  

PLaurence(at)the-beach.net writes:



Bob,



I have to agree on your take.



I learned to fly  partial panel with a turn coordinator ( along with the

other compliments of  instruments) which in my opinion is as  proficient as a

T&B.  However, my guess is that a lot of newer pilots flying today have  not

developed this skill.

BobsV35B(at)aol.com
Guest

Posted: Mon Jan 16, 2006 7:12 pm Post subject: EFIS Comparisons

In a message dated 1/16/2006 7:00:07 P.M. Central Standard Time,  

PLaurence(at)the-beach.net writes:



Is there  such a thing as a vacuum T/C?



Sorry, I  forgot to answer this.  

 

There has been. 

 

Brittain had one that they also used as the sensor for their low cost  

autopilot.  I do not recall seeing one that was not associated with an  autopilot or 

wing leveler.  Doesn't mean there isn't one though!

 

Happy  Skies,



Old Bob



Do Not  Archive

Kellym

Joined: 10 Jan 2006
Posts: 1705
Location: Sun Lakes AZ

Posted: Mon Jan 16, 2006 7:35 pm Post subject: EFIS Comparisons

Bob, the Brittain TC-100 you are refering to is both vacuum and electric 

powered, and will continue to function as long as either power source is 

present. I have one in my Mooney. As for recovering from a spin, while 

prepping for my instrument ride 26 years ago my CFI put me in an unusual 

attitude under the hood, and gave me the plane. The AH and DG were 

tumbled, so I knew I had to level the wings with the TC, and control the 

airspeed. Only afterwards, did I find out he put me in a spin...which I 

had never done at that point. Much easier recovery if you don't see the 

spinning earth out the window.



BobsV35B(at)aol.com wrote:

 	  Quote: 	
		   

 

  

 In a message dated 1/16/2006 7:00:07 P.M. Central Standard Time,  

 PLaurence(at)the-beach.net writes:

 

 Is there  such a thing as a vacuum T/C?

 

 

 

 Sorry, I  forgot to answer this.  

  

 There has been. 

  

 Brittain had one that they also used as the sensor for their low cost  

 autopilot.  I do not recall seeing one that was not associated with an  autopilot or 

 wing leveler.  Doesn't mean there isn't one though!

  

 Happy  Skies,

 

 Old Bob

 

 Do Not  Archive

_________________
Kelly McMullen
A&P/IA, EAA Tech Counselor # 5286
KCHD

Jerry Grimmonpre'

Joined: 09 Jan 2006
Posts: 144
Location: Huntley, Illinois 60142

Posted: Mon Jan 16, 2006 8:19 pm Post subject: EFIS Comparisons

Do Not Archive

Hi Bob ...

Do you know if a 12v electric 2 1/4" needle and ball instrument is 

available?

Jerry Grimmonpre'



---

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Mon Jan 16, 2006 8:45 pm Post subject: EFIS Comparisons

BobsV35B(at)aol.com wrote:



 	  Quote: 	
		   The T&B has one or two less fulcrums to fail, but both are about as  simple, 

 light and reliable as an instrument can be.


	


The internal construction of the TC and the T&SI (T&B) are the same. The

only difference is that the axis of the gyro in the TC is canted so that

the gyro responds to both yaw and roll rather than yaw only as in the T&SI.



 	  Quote: 	
		   I have mentioned this often, but I will repeat, I have two T&Bs in my  

 airplane, one is vacuum powered. The other is driven by electricity.  I  believe 

 that is overkill, but they are so cheap, I do it anyway!


	


Why don't you put in a second AI? Seems to me that would serve you

better than a second T&SI.



-- 

Brian Lloyd                         2243 Cattle Dr.

brian-yak at lloyd dot com          Folsom, CA 95630

+1.916.367.2131 (voice)             +1.270.912.0788 (fax)



I fly because it releases my mind from the tyranny of petty things . . .

- Antoine de Saint-Exupery

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Mon Jan 16, 2006 8:55 pm Post subject: EFIS Comparisons

Brinker wrote:

 	  Quote: 	
		   

 

       The GRT will also display the HSI from the SL30. And will tune the 

 SL30 from the MFD. Not to mention ILS and Localizer  And will display your 

 engine monitor to either display you choose. Not sure how you get 6k for 

 engine monitoring. Last I checked a 6cyl was around $1100 with EIS and 

 probes. 


	


I didn't think that was with the full graphical engine display.



 	  Quote: 	
		   GRT is very helpful if there is a way to make it work they will try. 

 I have a KLN90B gps that Todd is trying figure out if it will work with 

 they're system now. It looks favorable, I am keeping my fingures and toes 

 crossed.


	


The GRT should respond to ARINC-429 messages. If it does, it should be

compatible with any nav system that outputs ARINC-429 nav info, e.g.

CDI, VDI, flags, etc.



-- 

Brian Lloyd                         2243 Cattle Dr.

brian-yak at lloyd dot com          Folsom, CA 95630

+1.916.367.2131 (voice)             +1.270.912.0788 (fax)



I fly because it releases my mind from the tyranny of petty things . . .

- Antoine de Saint-Exupery

brian

Joined: 02 Jan 2006
Posts: 643
Location: Sacramento, California, USA

Posted: Mon Jan 16, 2006 9:32 pm Post subject: EFIS Comparisons

Bruce Gray wrote:

 	  Quote: 	
		   Chelton) remains untested to the extent necessary to pass DO 178, their

 hardware is not DO 160 certified. That means you're the beta tester. Do you

 want to bet your life in that situation? Mark my words, we're going to have

 some experimental airplanes equipped with low cost EFIS systems get into

 some serious fatal trouble. That body count is going to raise the level of

 visibility of this issue with the FAA and soon big brother will be breathing

 down our necks.

 

 Low cost, noncertified EFIS system are OK for VFR airplanes. But stay out of

 IFR conditions.


	


Bruce, there are a lot of airplanes flying IFR with the gyros powered by

a dry vacuum pump and you are worried about how dangerous the current

crop of non-certified PFDs are?



Instrument-rated pilots are supposed to be able to cross check their

gyros and reject those that do not agree. That is part of the standard

skill set.



When things go wrong and you start to chase a dying AI, you know it.

*EVERYTHING* feels wrong and your airspeed and altitude start to move.

You *KNOW* you have a problem. It will pretty quickly become apparent

which instrument(s) are providing you with valid information.



-- 

Brian Lloyd                         2243 Cattle Dr.

brian-yak at lloyd dot com          Folsom, CA 95630

+1.916.367.2131 (voice)             +1.270.912.0788 (fax)



I fly because it releases my mind from the tyranny of petty things . . .

- Antoine de Saint-Exupery

mlas(at)cox.net
Guest

Posted: Tue Jan 17, 2006 7:26 am Post subject: EFIS Comparisons

Bob,



Actually I stated that the artificial horizon was vacuum powered not the

T&B.  The only T&B that was vacuum powered as a normal course was on the

Mooneys, most were electric.  I think you need to read thing a little

more carefully.



As far as meeting the requirement of being able to fly a T&B, most IFR

pilots could do this when licensed but never practice this task again.

You tell me how good you would be 10 years down the road without

spending more then the 5 minutes or so work with the T&B on your BFR in

great weather.  Unless youre the one pilot in general aviation that

does go out every 90 days and maintains proficiency at this task.  I

think your hiding behind the lack of data showing that pilots do not

practice what they do not like or are not very good at.  I'm just being

realistic about the data I have collected about real world proficiency.



Mike



--

bobsv35b(at)aol.com
Guest

Posted: Tue Jan 17, 2006 8:33 am Post subject: EFIS Comparisons

Good Morning Brian,

 

You ask: "Why don't you put in a second AI? Seems to me that would serve you

better than a second T&SI."

 

Many reasons. 

 

I would need to repeat long treatises on why I prefer the T&B over the TC along with thoughts on how MY mind works.  What works for me may not work for others.

 

On top of that, the T&B is lighter, cheaper and, in my opinion, more reliable.

 

Incidentally, I have never disassembled either a T&B or a TC, but my local instrument guru tells me that the TC has one more fulcrum point to transfer the data from the canted gyro to the instrument face.  Thus a slightly higher parts count and an ever so slightly higher chance of failure.

 

There is no doubt that, with proper training, either a TC or a T&B can be used successfully for partial panel flight and as a device for recovery from an unusual attitude.

 

On top of that, neither instrument will tumble as will some attitude gyros. 

 

My love for the T&B is based on it being so much different in appearance from the TC or attitude gyro and the fact that it will show only yaw where the TC shows both roll and yaw.

 

Happy Skies,

 

Old Bob



 

--

Display posts from previous:

	Matronics Email Lists Forum Index -> AeroElectric-List	All times are GMT - 8 Hours Goto page Previous 1, 2, 3, 4, 5 Next
Page 3 of 5

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum