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Disorientation.

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rdunhamtn(at)hotmail.com
Guest

Posted: Thu Jun 22, 2006 1:07 pm Post subject: Disorientation.

Old Bob,



The Holiday Inn Express and Rocket surgery comments were designed to alert 

the unsuspecting reader of my lack of true experience and knowledge in this 

area. I wouldn't want to be misunderestimated ya know. Besides, I was 

agreeing with George! That shoulda tipped ya off. Take what I say for what 

it's worth.



I especially like to read your posts. You bring a depth and bredth of 

knowledge to the discussion which should remind us all of the great strides 

made in aviation, due in no small part to the efforts of men such as 

yourself. I do not take that lightly, sir. It has been said that we stand on 

the shoulders of giants. I agree 100% with that sentiment.



However ), may I respectfully submit that this IS the 21st century and a 

gyro is not necessarily a gyro anymore! Modern avionics include devices 

traditionally called gyro's that contain not even one moving part. Nothing 

to spin. Nothing to break. They are very reliable. Glass panels are selling 

like hotcakes. The DA-40 sports such a "technologically advanced" getup. Her 

backup instruments consist only of AI (imagine that), ASI, ALT and wet 

compass. No T&B and no TC. That's right, neither one! Why use EITHER a T&B 

OR a TC if you could have an AI? Better yet... a vacuum powered AI, an 

electric AI and an electronic AI. Now, just how many failure senarios can 

one imagine in which all three would go down simultaneously???



You mentioned training and proficiency. I submit that that is indeed the 

weak link in the NTSB reports scenario and the number 1 reason to backup 

with an AI. We simply must take into account the human factor. If we can 

design in a better backup, why on Earth wouldn't we??? It simply is not 

reasonable to expect human males to stay proficient at partial panel flying 

when they all just KNOW that they'll never need that skill. So much easier 

to slip an EFIS into that extra 3.25" hole and everybody lives long and 

prospers )



Rodney (wet behind the ears whipper snapper) in Tennessee



do not archive

BobsV35B(at)aol.com
Guest

Posted: Thu Jun 22, 2006 5:34 pm Post subject: Disorientation.

In a message dated 6/22/2006 6:35:05 P.M. Central Standard Time,  

rdunhamtn(at)hotmail.com writes:



You  mentioned training and proficiency. I submit that that is indeed the 

weak  link in the NTSB reports scenario and the number 1 reason to backup 

with  an AI. We simply must take into account the human factor. If we can 

design  in a better backup, why on Earth wouldn't we??? It simply is not  

reasonable to expect human males to stay proficient at partial panel  flying 

when they all just KNOW that they'll never need that skill. So much  easier 

to slip an EFIS into that extra 3.25" hole and everybody lives long  and 

prospers )



Rodney (wet behind the ears whipper snapper) in  Tennessee



Good Evening Rodney,

 

If you will check back on what I have written, you will note that I often  

mention that we should be getting something better than the T&B. The problem  

is, so far, nothing has been approved.

 

I also realize that an experimental airplane may not require an approved  

unit. Nevertheless, if I am going to hang my life on the instrumentation, I want  

it to be quite reliable. I do not have any experience with any of the GA 

style  EFIS units. I did fly the glass cockpit in the 767 when it first came on 

the  scene.  I am strongly in favor of all such improvements.

 

I particularly like the Dynon unit, but I have been told that it does not,  

as yet, meet the requirements of a certified set. Something about high rates of 

 rotation making it lose a signal? That may be way off base.

 

I do have an idea for a unit that I feel will be better than the T&B.  

Unfortunately, I have neither the expertise or the financial capability to make  any 

appropriate tests.

 

However, a bigger concern is determining the failure of a standard attitude  

instrument. What will happen to a solid state unit is beyond my knowledge.   

If you have two attitude instruments, choosing the one that is failing is not 

as  simple as it may seem. Even if you have three of them and the one that 

fails is  the one you are using, it is quite likely that your mind will be 

somewhat out of  synch before you discover the failure. If control of the aircraft is 

to be  maintained, the pilot must make a very rapid decision and take action 

that will  eliminate the offending instrument from use. The more experienced 

pilot has a  tougher job disregarding the failed instruments indication than 

does a low time  pilot. The problem has to do with our habit patterns. If we are 

devoting all of  our attention to keeping the airplane right side up, things 

work quite well.  However, as soon as we try to tune a radio or make any other 

manipulation, our  habits take over and a correction is likely to be made 

based on what the failed  unit is telling us. The easiest answer is to cover the 

offending instrument.  That gets rid of the unit that is providing false 

information.

 

It is easiest to fly strictly needle, ball, and airspeed if there is no  

other attitude instrumentation in the airplane.  I have never flown an  attitude 

gyro that would not tumble. If there is such a thing, I suppose it  would be 

acceptable. I imagine the solid state units currently used as backup by  the 

aircarriers are non tumbling, but the ones we had when I was gainfully  employed 

would tumble. In any case, you really do need a backup in which you  have 

absolute confidence.

 

There is not time to make evaluations and choices. Both JFK Jr and Carnahan  

went from somewhere around seven thousand feet to dead within forty-five  

seconds. Both had fully operative attitude indications available. Carnahan had  an 

instrument rating and a knowledgeable, though not IFR current, copilot.

 

If you have an autopilot to fly the airplane, that is obviously the best,  

but you will have very little time to make a decision to engage it. For complete 

 safety, it would have to be used as is the stability unit in an airbus. It 

needs  to be controlling the airplane full time.

 

Whatever unit you decide to use as your last ditch survival capability, you  

must know how to use it and be able to immediately have full confidence that  

what it is telling you is correct.

 

I have had the pleasure of using a T&B for recoveries when I was  inverted, 

in spins, in grave yard spirals and in fully stalled configurations.  If the 

needle is wiggling, I trust it. Whatever you choose must instill as much  trust 

in you as to your ability to recover the aircraft by it's use as I have  

developed trust in the T&B.

 

I hope for a modern replacement, I just have not yet seen one.

 

Happy  Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

Stearman  N3977A

Brookeridge Air Park LL22

Downers Grove, IL 60516

630  985-8503

brian

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

Posted: Thu Jun 22, 2006 7:31 pm Post subject: Disorientation.

On Jun 22, 2006, at 9:30 PM, BobsV35B(at)aol.com wrote:



 	  Quote: 	
		   I particularly like the Dynon unit, but I have been told that it  

 does not,

 as yet, meet the requirements of a certified set. Something about  

 high rates of

  rotation making it lose a signal? That may be way off base.


	


Not so far off-base Bob. All of the AHRS being used in various PFDs  

use solid-state rate gyros. Since these are rate gyros like the T&B,  

they cannot tumble.



Each AHRS has three rate gyros for pitch, roll, and yaw. Since a rate  

gyro cannot tell its initial position, i.e. which way is up, the AHRS  

incorporates three accelerometers. If the airplane is not  

accelerating at all, then there will be 1G sensed by the  

accelerometers. If the vector sum of the accelerations in all three  

axes has a magnitude of 1G then the "brain" knows that the airplane  

is not accelerating and the direction of the acceleration must be  

"up". That is then used to "erect" the gyro.



Once "up" has been determined the rate information will let you  

determine a new attitude. For instance, if the roll gyro senses a 10  

degree/sec rate of roll for three seconds then the airplane must be  

in a 30 degree bank.



But like all rate gyros, there is a maximum rate which may be sensed.  

Even the TC and T&B have this problem. Eventually the rate of yaw can  

get high enough that the needle is "pinned". An increase in yaw rate  

is not displayed on the T&C because the needle cannot move any  

farther. Solid state rate gyros have this same problem. If the rate  

is too high the gyro will indicate maximum rate even though that is  

not the correct rate. The "brain" does not sense the correct rate so  

it gets more and more behind. Now it no longer knows which way is  

"up". Since roll rates usually can exceed pitch or yaw rates, roll is  

usually the limiting factor.



Note that if, at any time, the airplane stops accelerating, even for  

a fraction of a second, the "brain" can use the accelerometer data to  

"reset" and "erect" the gyro.



Does this help?



BTW, I am going to try to talk my FSDO into letting me install a  

Dynon D-10 in the panel of my Aztec as an "extra" instrument without  

removing any of the stanard "six-pack". It strikes me as it would  

make a dandy backup to the iron gyros.



Brian Lloyd                         361 Catterline Way

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-Exupéry

_________________
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

rdunhamtn(at)hotmail.com
Guest

Posted: Fri Jun 23, 2006 4:04 am Post subject: Disorientation.

Old Bob,



With all due respect, the Kennedy and Carnahan crashes have nothing to do 

with the topic at hand. These accidents both happened due to COMPLACENCY and 

poor CRM and the proof of it is that they both died with functioning 

attitude indicators!



Kennedy failed to recognize the insidious onset of IMC and therefore did not 

transition to IFR but rather stayed VFR until too late. The classic VFR into 

IMC accident. He had functioning gyros and autopilot. It just never occurred 

to him that he should use them! That, my esteemed colleague, is the sina qua 

non of COMPLACENCY.



Carnahan also exhibited evidence of COMPLACENCY, launching into night IMC in 

a complex multiengine aircraft without a competent and proficient copilot 

while carrying precious cargo. He also may have suffered from a personality 

style not conducive to safe flight. He had a fully functioning gyro that the 

right seat pilot could easily have used. He needed to simply say to the 

pilot not flying, "You watch the good AI on your side and keep the wings 

level." I believe you heavy iron guys call that cockpit resource management, 

or CRM. The pilot not flying also had a personality style not conducive to 

safe flight. When the feces hit the fan, he was in a position to correct the 

situation by keeping the wings level using his functioning AI but he didn't. 

Exhibiting what I believe is referred to as inappropriate deference to 

authority. A macho "I can handle it" left seater and a passive "You can 

handle it better than me 'cause you're the PIC" right seater is a deadly 

combo.



Rodney (still wet behind his IFR ears) in Tennessee



do not archive

BobsV35B(at)aol.com
Guest

Posted: Fri Jun 23, 2006 4:45 am Post subject: Disorientation.

In a message dated 6/23/2006 7:10:25 A.M. Central Standard Time,  rdunhamtn(at)hotmail.com writes:

  	  Quote: 	
		  Rodney    (still wet behind his IFR ears) in Tennessee

	


 

Good Morning Rodney,

  

 I really do appreciate your efforts at analyzing the problems, but I do not  believe you fully comprehend the trouble some of us get into when orientation is  lost. 

  

 My knowledge of almost everything is limited, but I do know how it feels  when I get the wrong idea as to where up is located.

  

 My contention is that we need to emphasize that the turn needs to be  stopped. The rest can be sorted out later when the mind is back to normal.   Your mind is probably much more competent than is mine.  

  

 I know how confused I can get.

  

 By concentrating on nothing other than stopping the turn, I have been able  to survive. 

  

 It is my non scientifically analyzed firm belief that JFK Jr and Carnahan  were both very intelligent and well rounded personalities. If you have knowledge  of their human frailties, you have knowledge beyond any that I have now or will  ever attain.

  

 Had they gone to a last ditch mode of stopping the turn until their minds  settled down, I THINK they would have survived, but there is no doubt that I  could be very wrong!

  

 I totally disagree with your analysis that Complacency played a part in  either situation.

  

 Lack of PROPER training and practice played a MAJOR role.

  

 Happy  Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

Stearman  N3977A

Brookeridge Air Park LL22

Downers Grove, IL 60516

630  985-8503

avidsid(at)yahoo.com
Guest

Posted: Fri Jun 23, 2006 5:54 am Post subject: Disorientation.

Old Bob,

   

  I do believe you have missed the point here..........with all due respect, Rod has put the situation into perspective, and may actually be relating some of his own experience(s)!

   

  No one will ever know what those two pilots were  going through, but the known facts and with radars tapes to show the 'classic' symtoms.....its quite easy to see how the 'accidents' came to happen.  Not nice to see, but clearly something we all must learn and remember as ever evolving and learning pilots.

   

  Not trying to out vote you here, but we have to stick to the criteria for judging these cases..........staying alert to the changing environment as we fly is the training and learned lessons for all of us, complacency allows us to forget, ignore, or just overrule our best intentions and training.

   

  Believe your instruments, not the seat of your  pants, if, by chance, you should find yourself in something like they did. 

   

  Can I get a ride in your Stearman?

   

  Sid

  Alpena, Mi

  N204S

  --------------------------------



BobsV35B(at)aol.com wrote:

   	  Quote: 	
		          In a message dated 6/23/2006 7:10:25 A.M. Central Standard Time, rdunhamtn(at)hotmail.com writes:

   	  Quote: 	
		  Rodney (still wet behind his IFR ears) in Tennessee

	


  

Good Morning Rodney,

   

  I really do appreciate your efforts at analyzing the  problems, but I do not believe you fully comprehend the trouble some of us get into when orientation is lost. 

   

  My knowledge of almost everything is limited, but I do know how it feels when I get the wrong idea as to where up is located.

   

  My contention is that we need to emphasize that the turn needs to be stopped. The rest can be sorted out later when the mind is back to normal.  Your mind is probably much more competent than is mine.  

   

  I know how confused I can get.

   

  By concentrating on nothing other than stopping the turn, I have been able to survive. 

   

  It is my non scientifically analyzed firm belief that JFK Jr and Carnahan were both very intelligent and well rounded personalities. If you have knowledge of their human frailties, you have knowledge beyond any that I have now or will ever attain.

    

  Had they gone to a last ditch mode of stopping the turn until their minds settled down, I THINK they would have survived, but there is no doubt that I could be very wrong!

   

  I totally disagree with your analysis that Complacency played a part in either situation.

   

  Lack of PROPER training and practice played a MAJOR role.

   

  Happy Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

Stearman N3977A

Brookeridge Air Park LL22

Downers Grove, IL 60516

630 985-8503

	


"Why can't we all just get along?"

  		Yahoo! Sports Fantasy Football ’06 - Go with the leader.  [url=http://us.rd.yahoo.com/evt=33539/*http://football.fantasysports.yahoo.com?ovchn=YAH&ovcpn=Integration&ovcrn=Mail+footer&ovrfd=YAH&ovtac=AD]Start your league today![/url]

BobsV35B(at)aol.com
Guest

Posted: Fri Jun 23, 2006 6:31 am Post subject: Disorientation.

In a message dated 6/23/2006 8:59:26 A.M. Central Standard Time,  avidsid(at)yahoo.com writes:

  	  Quote: 	
		  I do believe you have missed the point  here.......... 	


 

 Here I must disagree. What has happened is that I have failed to make my  point. 

  

 If either of those unfortunate souls had stopped the turn, they would have  survived.

  

 Happy  Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

Stearman  N3977A

Brookeridge Air Park LL22

Downers Grove, IL 60516

630  985-8503

Jerry Grimmonpre'

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

Posted: Fri Jun 23, 2006 7:47 am Post subject: Disorientation.

Do Not Archive

Hi Bob ...

I've enjoyed this discussion and of course it has ignited my imagination as 

to what is the solution to what seems to be a an insurmountable problem. 

That problem seems to be  ... positive aircraft control without visual 

ground contact and with one instrument that's nearly 100% reliable.   I say 

nearly 100% reliable because pilots are known to hit the ground using the 

MK-1 Eyeball in severe clear visual conditions.  How does this happen while 

using what is supposedly the most reliable gage around.  The problem with 

the eyeball is it has to go through the brain to get to the muscle reaction 

for correction.  So maybe the brain is really the fault producer in the 

uninterrupted chain of events leading to the scene of the accident.  The 

brain can solve many problems associated with flight but it gets fooled by a 

few things.  Some of which are the ear, the ego and the pride.  They are so 

closely linked it's difficult to separate out which one got to the accident 

scene first.  I urge you to continue your discussion.  I write this with no 

intent to harm or inflame.



Someday, we'll have an situational display showing what the human eye would 

see while visual.  It will be generated with GPS signals and others as well, 

showing a moving horizon, multicolored fields, streams and highways.  Then 

we can do spins in the wx and even low level high speed passes.  Ooops there 

goes my ego and pride showing again!  Down boy!!

Respectfully submitted to my colleague and mentor, Old Bob ...

Jerry Grimmonpre'

Flying RV4

RV8A Electrical

Sent: Thursday, June 22, 2006 8:30 PM

 	  Quote: 	
		   



 In a message dated 6/22/2006 6:35:05 P.M. Central Standard Time,

 rdunhamtn(at)hotmail.com writes:



 You  mentioned training and proficiency. I submit that that is indeed the

 weak  link in the NTSB reports scenario and the number 1 reason to backup

 with  an AI. We simply must take into account the human factor. If we can

 design  in a better backup, why on Earth wouldn't we??? It simply is not

 reasonable to expect human males to stay proficient at partial panel 

 flying

 when they all just KNOW that they'll never need that skill. So much 

 easier

 to slip an EFIS into that extra 3.25" hole and everybody lives long  and

 prospers )



 Rodney (wet behind the ears whipper snapper) in  Tennessee

Terry Watson

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

Posted: Fri Jun 23, 2006 9:32 am Post subject: Disorientation.

Brain,



Something that I think needs to be mentioned here is that, according to my

understanding my Bluemountain EFIS/one and some other solid state AHRS

systems use GPS as an input to in a sense keep the AHRS honest. I looked for

but couldn't find the discussions about how this works.



Terry

RV-8A with BMA efis/one finishing

Seattle






<snip>



Each AHRS has three rate gyros for pitch, roll, and yaw. Since a rate  

gyro cannot tell its initial position, i.e. which way is up, the AHRS  

incorporates three accelerometers. If the airplane is not  

accelerating at all, then there will be 1G sensed by the  

accelerometers. If the vector sum of the accelerations in all three  

axes has a magnitude of 1G then the "brain" knows that the airplane  

is not accelerating and the direction of the acceleration must be  

"up". That is then used to "erect" the gyro.



Once "up" has been determined the rate information will let you  

determine a new attitude. For instance, if the roll gyro senses a 10  

degree/sec rate of roll for three seconds then the airplane must be  

in a 30 degree bank.



But like all rate gyros, there is a maximum rate which may be sensed.  

Even the TC and T&B have this problem. Eventually the rate of yaw can  

get high enough that the needle is "pinned". An increase in yaw rate  

is not displayed on the T&C because the needle cannot move any  

farther. Solid state rate gyros have this same problem. If the rate  

is too high the gyro will indicate maximum rate even though that is  

not the correct rate. The "brain" does not sense the correct rate so  

it gets more and more behind. Now it no longer knows which way is  

"up". Since roll rates usually can exceed pitch or yaw rates, roll is  

usually the limiting factor.



Note that if, at any time, the airplane stops accelerating, even for  

a fraction of a second, the "brain" can use the accelerometer data to  

"reset" and "erect" the gyro.



Does this help?



BTW, I am going to try to talk my FSDO into letting me install a  

Dynon D-10 in the panel of my Aztec as an "extra" instrument without  

removing any of the stanard "six-pack". It strikes me as it would  

make a dandy backup to the iron gyros.



Brian Lloyd                         361 Catterline Way

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-Exupéry

bferrell(at)123mail.net
Guest

Posted: Fri Jun 23, 2006 9:55 am Post subject: Disorientation.

Terry,



This has been true with the BMA products, but apparently the latest generation

does not do this.

http://www.bluemountainavionics.com/talk/showpost.php?p=9447&postcount=10



Brett



Quoting Terry Watson <terry(at)tcwatson.com>:



 	  Quote: 	
		   



 Brain,



 Something that I think needs to be mentioned here is that, according to my

 understanding my Bluemountain EFIS/one and some other solid state AHRS

 systems use GPS as an input to in a sense keep the AHRS honest. I looked for

 but couldn't find the discussions about how this works.



 Terry

 RV-8A with BMA efis/one finishing

 Seattle



 



 <snip>



 Each AHRS has three rate gyros for pitch, roll, and yaw. Since a rate

 gyro cannot tell its initial position, i.e. which way is up, the AHRS

 incorporates three accelerometers. If the airplane is not

 accelerating at all, then there will be 1G sensed by the

 accelerometers. If the vector sum of the accelerations in all three

 axes has a magnitude of 1G then the "brain" knows that the airplane

 is not accelerating and the direction of the acceleration must be

 "up". That is then used to "erect" the gyro.



 Once "up" has been determined the rate information will let you

 determine a new attitude. For instance, if the roll gyro senses a 10

 degree/sec rate of roll for three seconds then the airplane must be

 in a 30 degree bank.



 But like all rate gyros, there is a maximum rate which may be sensed.

 Even the TC and T&B have this problem. Eventually the rate of yaw can

 get high enough that the needle is "pinned". An increase in yaw rate

 is not displayed on the T&C because the needle cannot move any

 farther. Solid state rate gyros have this same problem. If the rate

 is too high the gyro will indicate maximum rate even though that is

 not the correct rate. The "brain" does not sense the correct rate so

 it gets more and more behind. Now it no longer knows which way is

 "up". Since roll rates usually can exceed pitch or yaw rates, roll is

 usually the limiting factor.



 Note that if, at any time, the airplane stops accelerating, even for

 a fraction of a second, the "brain" can use the accelerometer data to

 "reset" and "erect" the gyro.



 Does this help?



 BTW, I am going to try to talk my FSDO into letting me install a

 Dynon D-10 in the panel of my Aztec as an "extra" instrument without

 removing any of the stanard "six-pack". It strikes me as it would

 make a dandy backup to the iron gyros.



 Brian Lloyd                         361 Catterline Way

 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-Exupéry

BobsV35B(at)aol.com
Guest

Posted: Fri Jun 23, 2006 11:15 am Post subject: Disorientation.

Good Afternoon Jerry,

   

 Great to hear from you. I trust your project is progressing well?

  

 I believe we are on the same page. 

  

 I keep hoping some device will be invented that has suitable reliability,  will be usable in all flight attitudes, and that will require no special  training. 

  

 I also feel our biggest problem is how hard it is to convince those who  have not been there of the tricks that can be visited upon the minds of most of  us.

  

 So far, the T&B, with suitable training, has been my instrument of  choice. It does seem that, with all that has been done in the roughly eighty  years since it was first used, we should be able to come up with something that  is better!

  

 The fact that we are losing airplanes that are equipped with working  attitude gyros tells me that the current attitude gyro is NOT the answer.

  

 Do you recall the Itzahk Jacoby accident? His attitude gyro was working  just fine. It appears that it was his directional indicator and TC that had  failed. Following Itzahk's accident, I added a second T&B to my panel. That  put me back to the same setup I had in my first Bonanza over fifty years  ago!

  

 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 6/23/2006 10:53:01 A.M. Central Standard Time,  jerry(at)mc.net writes:

  	  Quote: 	
		  Do Not    Archive

Hi Bob ...

I've enjoyed this discussion and of course it has    ignited my imagination as 

to what is the solution to what seems to be a an    insurmountable problem. 

That problem seems to be  ... positive    aircraft control without visual 

ground contact and with one instrument    that's nearly 100% reliable.   I say 

nearly 100% reliable    because pilots are known to hit the ground using the 

MK-1 Eyeball in    severe clear visual conditions.  How does this happen while 

using    what is supposedly the most reliable gage around.  The problem with    

the eyeball is it has to go through the brain to get to the muscle    reaction 

for correction.  So maybe the brain is really the fault    producer in the 

uninterrupted chain of events leading to the scene of the    accident.  The 

brain can solve many problems associated with flight    but it gets fooled by a 

few things.  Some of which are the ear, the    ego and the pride.  They are so 

closely linked it's difficult to    separate out which one got to the accident 

scene first.  I urge you    to continue your discussion.  I write this with no 

intent to harm or    inflame.



Someday, we'll have an situational display showing what the    human eye would 

see while visual.  It will be generated with GPS    signals and others as well, 

showing a moving horizon, multicolored fields,    streams and highways.  Then 

we can do spins in the wx and even low    level high speed passes.  Ooops there 

goes my ego and pride showing    again!  Down boy!!

Respectfully submitted to my colleague and mentor,    Old Bob ...

Jerry Grimmonpre'

Flying RV4

RV8A  Electrical

rdunhamtn(at)hotmail.com
Guest

Posted: Fri Jun 23, 2006 1:20 pm Post subject: Disorientation.

Dear Old Bob,



It would be an honor to have you seated next to me showing me the ropes. I 

know I'm a smart-a$$ kid wet behind the ears in such matters. I yield to 

your experience and knowledge.



Rodney in Tennessee



dio not archive

avidsid(at)yahoo.com
Guest

Posted: Fri Jun 23, 2006 6:21 pm Post subject: Disorientation.

they augered in, how does this have anything to do with turning...........wings level you can still die, straight down.

  shee................

  Sid

  write to me personally        avidsid(at)yahoo.com (avidsid(at)yahoo.com)     I'm interested in your thought process on this one.

   

  ------------------------------------enough, unless its more to the point of homebuilt electrics.

   

  



BobsV35B(at)aol.com wrote:

   	  Quote: 	
		        In a message dated 6/23/2006 8:59:26 A.M. Central Standard Time, avidsid(at)yahoo.com writes:

   	  Quote: 	
		  I do believe you have missed the point here.......... 	


  

  Here I must disagree. What has happened is that I have failed to make my point. 

   

  If either of those unfortunate souls had stopped the turn, they would have survived.

   

  Happy Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

Stearman N3977A

Brookeridge Air Park LL22

Downers Grove, IL 60516

630 985-8503

	


"Why can't we all just get along?"

  Get on board. [url=http://us.rd.yahoo.com/evt=40791/*http://advision.webevents.yahoo.com/handraisers]You're invited[/url] to try the new Yahoo! Mail Beta.

brian

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

Posted: Sat Jun 24, 2006 12:22 pm Post subject: Disorientation.

On Jun 23, 2006, at 3:11 PM, BobsV35B(at)aol.com (BobsV35B(at)aol.com) wrote:

 	  Quote: 	
		      So far, the T&B, with suitable training, has been my instrument of choice. It does seem that, with all that has been done in the roughly eighty years since it was first used, we should be able to come up with something that is better!



	


Well, the instruments aren't the problem; it is the human brain. It has to decide which instrument is lying when it is lying to itself.



 	  Quote: 	
		    

 The fact that we are losing airplanes that are equipped with working attitude gyros tells me that the current attitude gyro is NOT the answer.



	


Actually I think that the attitude gyro *IS* the answer. It tells you the attitude of the airplane, plain and simple. When all else fails you want to get the airplane straight and level. If the wings are level and the nose is not up or down, the airplane is not going to be doing anything nasty.



The real problem is when the AI lies to you. When the AI fails and doesn't tell you that it has failed, you have to rely on secondary indications that it has failed, e.g. if the AI says you are straight and level while the T&B is pinned and the airspeed indicator is rapidly increasing, the AI is lying to you. And you are right that AI's are prone to failure. The iron AI is a complex mechanical device with an MTBF of about 500 hours. Not exactly the thing I want to stake my life on. (In spite of the fact that I have staked my life on such a critter for a long time flying IFR.)



Because the AI is more complex than the T&B it is far more likely that the AI will fail than that the T&B will fail. Likewise the airspeed indicator is pretty darned simple and unlikely to fail. That is why people have been trusting them over vertical gyros for a long time.



But it is possible to build a vertical gyro that exceeds both the T&B and the ASI in reliability. The current crop of AHRS use solid state rate gyros and solid-state accelerometers that have mean-times between failure (MTBF) measured in hundreds of thousands of hours, not hundreds of hours like our current crop of iron gyros (T&B included). They don't have motors and they don't have bearings. They just aren't likely to break. You have to make sure that your rate gyros are capable of handling the maximum rates of pitch, roll, and yaw that your airplane can achieve, even in departed flight. That is very possible to do. 



Now you do want to accommodate those times when something does fail. For that you build in triple redundancy. Three AHRS with a voting unit that allows two of the AHRS to override bogus information from the third. At that point you have a system that is so unlikely to fail that you don't need to worry about it anymore.



So rather than talking about which iron gyros one wants to have in the panel it is time to think in terms of fail-safe instrumentation now that it is both possible and cost effective to do so.

 	  Quote: 	
		  

 



	




 Brian Lloyd                         361 Catterline Waybrian-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-Exupéry

brian

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

Posted: Sat Jun 24, 2006 1:53 pm Post subject: Disorientation.

Sometimes it is best to get back to basics. There is a great deal of  

both heat and light going on here so I am going to go back to looking  

at the forest instead of the trees.



Bob Nuckolls has been doing a very good job of getting people to  

think about systems, how they fail, and how to minimize the impact  

when they fail. I am going to try to use some of his approach in the  

selection of instrumentation systems.



First, we need to ask ourselves some questions:



1. What is most likely to fail?



2. How do I know it has failed?



3. What is the impact on my flight if this fails?



I am going to start with the most basic answer to item #1: power.  

Power for your instruments is the most likely thing to fail. 'Lectric  

Bob has shown you how to deal with this problem with things that eat  

electricity. I can't add anything here. OTOH if you have chosen to  

use air-powered gyros (for God's sake why?) then you need to know how  

you are going to recognize and deal with that. Backup air supply is a  

lot more difficult than a backup electrical power supply. Still, it  

is possible.



OK, you have dealt with power and we need to go back up to the top of  

our list and ask again, what is most likely to fail? I would hold  

that it is probably our iron AI as that is the least reliable of the  

gyros. Now the next two questions becomes critical. How do you detect  

failure of the AI and what impact is that going to have on your  

operations?



The simplest answer I can come up with is: know thy instruments. Get  

a sim and practice having the thing fail your various gyros and then  

keep doing it over and over until you know what to expect and how to  

deal with it. (BTW, set the sim for moderate turbulence as that is  

what you are going to have when the gyro fails.) I would hold that it  

is not flying partial-panel that kills people so much as the brain  

trying to detect the failure of the AI and then transition to partial- 

panel flying. This transition is much like "continued VFR into IMC."  

It isn't the same and the rules have just changed. You have to make  

that mental switch and most people just don't do that very well. You  

have to practice making that mental switch so that you become  

comfortable with it. Frankly, the choice of T&B vs. TC has a very  

small impact when compared to making that mental choice to a) detect  

instrument failure and, b) change to partial-panel flying.



And BTW, having your instructor slap a post-it over the AI and say,  

"you just lost your AI," does NOT count. He/she has already  

simplified your decision-making process by making the decision for  

you. The only way to really get a feel for it is to have it sneak up  

on you insidiously and that is only going to happen is in a sim or  

for real.



Soon we will have fail-safe gyro panels using multiple solid-state  

gyros. Right now you can't buy one. Right now no matter what you have  

you will need to detect and deal with instrument failure regardless  

of whether it is iron or glass. Figure out how you are going to do  

that or don't fly IFR.

Brian Lloyd                         361 Catterline Way

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-Exupéry

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