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steveadams

Joined: 10 Jan 2006
Posts: 191

Posted: Fri Mar 02, 2007 12:16 pm Post subject: Backup Electric Vacuum Pump

I know the trend is toward glass, however that can be a major project and expense for those of us with steam gauges. A backup electric AI costs about the same as a Dynon. I was wondering if anyone has tried putting in a simple electric vacuum pump as a backup to the engine driven pump. I don't know what kind of flow you would need to reliably power the gyros, but it seems it would be a relatively inexpensive and simple retrofit that could even be tied in to a switch to automatically power the pump when the vacuum pressure drops. I guess it would also be useful for those converting to glass, who could keep their old gyros as backup, and still get rid of the engine driven vacuum pump. I know there is a certified electric pump that costs over $1000, but there are a lot of non-aircraft air pumps that could probably do the job for a lot less. Any suggestions or experience with this?

BobsV35B(at)aol.com
Guest

Posted: Fri Mar 02, 2007 2:02 pm Post subject: Backup Electric Vacuum Pump

Good Afternoon Steve,   

 What I don't understand is why more folks don't use venturi's.   They work well, are cheap and are very reliable. If they are mounted on the  belly in the path of the airflow from the engine, they even have reasonable  protection from ice.  

  

 Many airplanes flew in heavy IFR weather for many years using nothing but a  venturi to power all of the instruments. What gave venturi's a bad name was when  foolish people started to mount them on the side of the fuselage instead in the  airstream behind the engine.  I have a small venturi powering a single  T&B. If all else fails, I can easily control the airplane with just that one  T&B. If I have any altitude information at all it is easy. Add a  handheld GPS and I have more than the fanciest airplanes had in the thirties.  

  

 I will say that very few people receive as much training as they should in  the use of partial panel.

  

 Along that line, it is a LOT cheaper to take twenty hours of dual in  partial panel operations than it is to buy any standby horizon. And the training  will help in any airplane.  One point though. Partial panel can be done  with a turn coordinator, but I much prefer the classic T&B. It is about the  most reliable mechanical instrument we have ever had. Some day, I am sure there  will be a solid state turn indicator that will replace the T&B. However,  until that time. Get a T&B, power it with a small venturi and spend a  thousand bucks on dual training getting thoroughly familiar with using the  T&B to control the airplane.

  

 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 3/2/2007 2:19:29 P.M. Central Standard Time,  dr_steve_adams(at)yahoo.com writes:

  	  Quote: 	
		  I know    the trend is toward glass, however that can be a major project and expense for    those of us with steam gauges. A backup electric AI costs about the same as a    Dynon. I was wondering if anyone has tried putting in a simple electric vacuum    pump as a backup to the engine drove pump. I don't know what kind of flow you    would need to reliably power the gyros, but it seems it would be a relatively    inexpensive and simple retrofit that could even be tied in to a switch to    automatically power the pump when the vacuum pressure drops. I guess it would    also be useful for those converting to glass, who could keep their old gyros    as backup, and still get rid of the engine driven vacuum pump. I know there is    a certified electric pump that costs over $1000, but there are a lot of    non-aircraft air pumps that could probably do the job for a lot less. Any    suggestions or experience with this?

	


 



  



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klehman(at)albedo.net
Guest

Posted: Fri Mar 02, 2007 2:03 pm Post subject: Backup Electric Vacuum Pump

The engine intake manifold works fine anytime you are not at full power.

With some partial panel practice, an electric Turn & Bank is also a 

sufficient backup for most aircraft.

Some folks like 3 items so you have a tie breaker when one goes wonky.  

I have a vacuum and an electric T&B plus a low vacuum warning from the EIS.

Ken



steveadams wrote:



 	  Quote: 	
		  



I know the trend is toward glass, however that can be a major project and expense for those of us with steam gauges. A backup electric AI costs about the same as a Dynon. I was wondering if anyone has tried putting in a simple electric vacuum pump as a backup to the engine driven pump. I don't know what kind of flow you would need to reliably power the gyros, but it seems it would be a relatively inexpensive and simple retrofit that could even be tied in to a switch to automatically power the pump when the vacuum pressure drops. I guess it would also be useful for those converting to glass, who could keep their old gyros as backup, and still get rid of the engine driven vacuum pump. I know there is a certified electric pump that costs over $1000, but there are a lot of non-aircraft air pumps that could probably do the job for a lot less. Any suggestions or experience with this?

nuckollsr(at)cox.net
Guest

Posted: Fri Mar 02, 2007 2:46 pm Post subject: Backup Electric Vacuum Pump

At 12:16 PM 3/2/2007 -0800, you wrote:



 	  Quote: 	
		  

<dr_steve_adams(at)yahoo.com>



I know the trend is toward glass, however that can be a major project and 

expense for those of us with steam gauges. A backup electric AI costs 

about the same as a Dynon. I was wondering if anyone has tried putting in 

a simple electric vacuum pump as a backup to the engine driven pump. I 

don't know what kind of flow you would need to reliably power the gyros, 

but it seems it would be a relatively inexpensive and simple retrofit that 

could even be tied in to a switch to automatically power the pump when the 

vacuum pressure drops. I guess it would also be useful for those 

converting to glass, who could keep their old gyros as backup, and still 

get rid of the engine driven vacuum pump. I know there is a certified 

electric pump that costs over $1000, but there are a lot of non-aircraft 

air pumps that could probably do the job for a lot less. Any suggestions 

or experience with this?


	


    While in the employ of Electro-Mech in the early 80s we

    were among the several companies that brought electrically

    driven, stand-by vacuum pumps to the GA market. First,

    know that the energy required is not insubstantial. As

    I recall, our 28 volt offering drew about 6 amps of current.

    A 14 volt would be about twice that much. Second, you'll need

    to supply some sort of transfer valve in the plumbing.

    Be wary of automatic valves . . .  a stuck transfer

    valve contributed to the sad outcome of this event:



http://www.aeroelectric.com/articles/N79NL.pdf



    Then there's the weight. I'm thinking that the

    s/b vacuum system adds about 6 pounds of weight.



    Bob . . .



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

        ( IF one aspires to be "world class",  )

        ( what ever you do must be exercised   )

        ( EVERY day . . .                      )

        (                  R. L. Nuckolls III  )

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

bob(at)bob-white.com
Guest

Posted: Fri Mar 02, 2007 4:25 pm Post subject: Backup Electric Vacuum Pump

Hi Steve,



I looked at a couple of things to generate a vacuum.  Some cars in the

early 90's had an electric smog pump.  I bought one on ebay for about

$100 and found that it pulled over 10 amps at 13 V and connecting it to

the vacuum system left over from the removal of a Lycoming didn't

provide enough vacuum to run a DG and an artificial horizon.  There are

vacuum pumps used to provide a vacuum in electric cars but they were

more like $200-$300 and I wasn't willing to spend that much to

experiment.  There may be a setup that works but it isn't trivial. 



I bought a TruTrak ADI and it seems to work well. Unfortunately the

heading info is GPS based so if you don't have a good GPS signal you

don't have heading (actually track).



If you must have a vacuum instrument, I think Old Bob's advice is good.

Use a venturi to run a T&B



Bob W.

On Fri,  2 Mar 2007 12:16:54 -0800

"steveadams" <dr_steve_adams(at)yahoo.com> wrote:



 	  Quote: 	
		   

 

 I know the trend is toward glass, however that can be a major project and expense for those of us with steam gauges. A backup electric AI costs about the same as a Dynon. I was wondering if anyone has tried putting in a simple electric vacuum pump as a backup to the engine driven pump. I don't know what kind of flow you would need to reliably power the gyros, but it seems it would be a relatively inexpensive and simple retrofit that could even be tied in to a switch to automatically power the pump when the vacuum pressure drops. I guess it would also be useful for those converting to glass, who could keep their old gyros as backup, and still get rid of the engine driven vacuum pump. I know there is a certified electric pump that costs over $1000, but there are a lot of non-aircraft air pumps that could probably do the job for a lot less. Any suggestions or experience with this?

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=98343#98343

 

 

 

 

 

 

 

 

 

 


	




-- 

N93BD - Rotary Powered BD-4 - http://www.bob-white.com

First Flight:  11/23/2006 7:50AM - 3.3 Hours Total Time

Cables for your rotary installation - http://www.roblinphoto.com/shop/

Jerry Grimmonpre'

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

Posted: Sat Mar 03, 2007 11:30 am Post subject: Backup Electric Vacuum Pump

Hi Bob ...

 Couldn't agree more with the idea of using a venturi's to drive a single  instrument.  The idea of driving a vacuum driven horizon has pulled at me  for some time.  The group of three info providing life savers ...  attitude, airspeed and altitude are all air driven and simple.  The  only one needing vacuum could easily be driven with an 8" venturi.  The  venturi does require high velocity air over and through it to pull the  vacuum.  My son and I were experimenting yesterday with a venturi 6"  long X 2" diameter.  It will drive a turn needle (as it's designed to do)  but a horizon needs more beef to sustain it.  I like the idea of putting  the venturi in the cowl exit air and I will try that with a couple other  venturi's.  I also will create a gill type venturi which could be  placed on the side of the fuselage, right beside the inst panel so the vacuum  could be within about a foot of the horizon.  When I have the mods  completed on my RV4 (before Spring) it will be used for this test  bed.  The venturi is but one of these test items.  Has anyone on  the list messed with a gill type venturi?   My fondest hope would be  to create something made similar a NACA vent that could simply be bonded/riveted  onto the sheet metal and plug in a vacuum line.  Done!  It's probably  more involved than just that but it's the essence of the thought.

  

 You have to admit Bob, one peek at a vacuum horizon is worth 20 peeks at a  T&B ... : )

 Jerry Grimmonpre

 [quote]   ---

N6030X(at)DaveMorris.com
Guest

Posted: Sat Mar 03, 2007 12:03 pm Post subject: Backup Electric Vacuum Pump

I don't know about you guys, but if I were building an experimental 

and had no Type Certificate I had to abide by, I would be spending my 

time figuring out how to build a bullet proof electrical system and 

getting rid of anything that had the word Vacuum in it.  It's an old, 

archaic technology that, at the present date, serves ONLY to make 

gyros cheaper.  The vacuum pumps are less reliable or long-lived than 

an alternator, and you're basically building a parallel power system 

for gyros that adds weight and complexity, hoses, filters, etc, and 

so on.  If you've got redundant electrical, and you are now worrying 

about a backup vacuum system, you're basically building QUADRUPLE 

parallel systems to power gyros.  That's insane to me.



Build redundancy into the electrical system, use solid state gyros, 

eschew vacuum.  Or was that "escrew"?



Dave Morris

Stuck in the 60's with a vacuum powered Mooney



At 01:29 PM 3/3/2007, you wrote:

[quote]Hi Bob ...

Couldn't agree more with the idea of using a venturi's to drive a 

single instrument.  The idea of driving a vacuum driven horizon has 

pulled at me for some time.  The group of three info providing life 

savers ... attitude, airspeed and altitude are all air driven and 

simple.  The only one needing vacuum could easily be driven with an 

8" venturi.  The venturi does require high velocity air over and 

through it to pull the vacuum.  My son and I were experimenting 

yesterday with a venturi 6" long X 2" diameter.  It will drive a 

turn needle (as it's designed to do) but a horizon needs more beef 

to sustain it.  I like the idea of putting the venturi in the cowl 

exit air and I will try that with a couple other venturi's.  I also 

will create a gill type venturi which could be placed on the side of 

the fuselage, right beside the inst panel so the vacuum could be 

within about a foot of the horizon.  When I have the mods completed 

on my RV4 (before Spring) it will be used for this test bed.  The 

venturi is but one of these test items.  Has anyone on the list 

messed with a gill type venturi?   My fondest hope would be to 

create something made similar a NACA vent that could simply be 

bonded/riveted onto the sheet metal and plug in a vacuum 

line.  Done!  It's probably more involved than just that but it's 

the essence of the thought.



You have to admit Bob, one peek at a vacuum horizon is worth 20 

peeks at a T&B ... : )

Jerry Grimmonpre

---

BobsV35B(at)aol.com
Guest

Posted: Sat Mar 03, 2007 12:44 pm Post subject: Backup Electric Vacuum Pump

In a message dated 3/3/2007 1:31:39 P.M. Central Standard Time,  jerry(at)mc.net writes:

  	  Quote: 	
		     You have to admit Bob, one peek at a vacuum horizon is worth 20 peeks at    a T&B ... : )

   Jerry Grimmonpre

	


 

Good Afternoon Jerry,

  

 I am not so sure I would agree. It is possible to have two artificial  horizons that are both active and that change attitude when you roll, but one  may be accurate and the other not.  You have to decide which is  correct.

  

 Attitude gyros do occasionally get the "leans". 

  

 In at least ninety-nine and forty-four one hundredths of a percent of the  times, if the T&B is wiggling, it is working.  

  

 And, if we are confused as to where up is, it is hard to believe an  instrument that does not agree with our senses. However, we don't have to agree  with the T&B. If it says we are not turning , we will survive. It makes no  difference at all where we think up is. No turns, no problem!

  

 Not only that, but even a cheap old airline pilot can afford one.

  

 Happy  Skies,



Old Bob

AKA

Bob Siegfried

Ancient Aviator

Stearman  N3977A

Brookeridge Air Park LL22

Downers Grove, IL 60516

630  985-8503



AOL now offers free email to everyone.  Find out more about what's free from AOL at AOL.com. 

  [quote][b]

nuckollsr(at)cox.net
Guest

Posted: Sat Mar 03, 2007 9:22 pm Post subject: Backup Electric Vacuum Pump

>At 09:23 PM 3/3/2007 -0500, you wrote:



 >Good Evening Bob,



 >May I take that to mean that you would want a GPS aided wing leveler in a 

Stearman?,

 >Piper Cub?, Luscombe?, Cessna 140? Cessna 172, Beech Musketeer?,

 >Beech Bonanza? North American AT-6? Twin Beech?



   Sure, why not? The answer is simple for most owners

   but for myself, I wouldn't own one of those airplanes

   because I need to stand in line at too many windows

   begging permission to make it better.



 >Where would you draw the line? All of the above? None of the

 >above? Some of the above?



   You have just illuminated the reason that those airplanes

   are all rotting away never to be replaced.  The GPS

   aided wing leveler is mechanically no more difficult to

   install in one of those airplanes than in an RV. But

   those who claim to know more about what's good for us

   have become the mill-stones between which those airplanes

   are slowly turning to dust.



 >I have never flown any airplane that had a GPS aided wing lever

 >though I have flown and owned plenty that did have wing levelers.

 >We all have to make individual decisions on what we feel meets our

 >individual level of risk, but requiring a GPS aided wing leveler

 >is not real high on my list of necessities. Interesting that you

 >think such a device is imperative.



   Depends on what your design goals are. For most of the

   the folks on this List, reducing cost of ownership is

   a goal. Dependency on a T&B traded for dependency on

   a GPS aided wing leveler offers a lower cost of ownership

   over the lifetime of the airplane.



 >Just goes to show, there is a wide range of desires among us all.



   If the "desire" is to minimize the probability of an

   unhappy ending to a piece of equipment failing, then

   the design goals are pretty clear.  I've watched the

   conversations here on the List and elsewhere for

   over a decade that vigorously debated the value of

   this technique or piece of equipment over that . . .

   But seldom did the conversation recommend reversion

   modes that reduce, not increase pilot workload.



   I'm dead-nuts serious about the admonition in my

   signature tag . . . an exceedingly small number of pilots

   accomplish daily practice for standard (much less reversion)

   modes flight in IMC. I understand that you may be personally

   comfortable . . . and perhaps world class in skills and

   willingness to fly through clouds with the venerable tools

   of yesteryear. I've done it too. But I cannot in good

   conscience recommend that the neophyte builder embrace

   these techniques today when there are better options that

   are cheap as a percentage of the total cost of acquiring,

   owning and operating an airplane.



   In a cost-of-ownership accounting, the venturi-driven

   T&B offered as a gift will be more expensive in $time$

   expended than what's needed to install the modern alternative.

   Further, the GPS aided wing leveler adds value to a

   high percentage of every flight while the T&B is useful

   for calibrating your rudder pressure on climb-out,

   setting rudder trim, and being there to assist with the

   management of a failure that you hope will never come but

   demands a perpetual investment of $time$ to make sure

   you are ready when it does.



   Very few of us are professional pilots. Those of us

   who are should be mindful of advice which presumes that

   all listeners are interested in (or even capable of) achieving

   levels of proficiency needed to avoid quantum jumps

   in risk after certain failures.  This isn't about a "wide

   range of desires" but simple failure modes effects analysis

   in a market place where the pilots come with a wide range

   of capability and willingness to spend $time$ necessary

   to level the risks if not lower them.



   One of the reasons why I see an opportunity for OBAM aviation

   to excel in accident reduction is because we can readily

   take advantage of modernization opportunities for reducing

   workload without begging anyone's permission.



   When the GPS aided wing leveler is present, failure of the

   primary display does not generate an immediate need

   to revert to a whole new mode of flying.  When one is

   depending on primary attitude displays to stay upright,

   then reversion to N/B/AS aviating at the same level of risk

   demands and investment of $time$ for maintenance of

   proficiency. The GPS aided wing leveler will hold track to

   within a degree or so all day, every day and doesn't need a

   bit of practice to stay "world class" at the task.



        Bob . . .



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

        ( IF one aspires to be "world class",  )

        ( what ever you do must be exercised   )

        ( EVERY day . . .                      )

        (                  R. L. Nuckolls III  )

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

BobsV35B(at)aol.com
Guest

Posted: Sun Mar 04, 2007 6:21 am Post subject: Backup Electric Vacuum Pump

Good Morning 'Lectric Bob,   

 Thank you for the very complete analysis of my position on the validity of  using a T&B and venturi as a low cost back up to whatever else is deemed  desirable in a flying machine.

  

 I have been reading your freely presented views since the days when the  connection was from Down By The Riverside Press. (or, something close to  that)

  

 Always a pleasure and your writings are always able to jiggle some thought  out of my very uneducated brain.

  

 Nevertheless, I do think my responses have some merit.

  

 The original question that started this particular string had to do with  providing a low cost source of vacuum.

  

 The Venturi is a low cost option.

  

 It is susceptible to icing, but when placed in a warm airstream behind the  engine it has been shown to handle ice quite well. Vacuum pumps do fail.  Especially the modern dry pumps if they are not replaced or serviced in  accordance with the manufacturers instructions.

  

 I still think the venturi is a viable option.

  

 I recognize that you cannot take the time to read everything on this list.  However, I think you would find that I have always said that I will happily  embrace a newer technology whenever it fits my needs (and my price point!).  There is nothing I would like better than having a solid state autopilot that  would be reliable enough such that I did not have to know how to fly by  instruments to be able to operate in cloud.

  

 If I were to be dropped in the wilderness with nothing to sustain me, I  would surely die. Many of my ancestors would have been able to survive in those  same conditions.

  

 Having accepted modern conveniences to keep me alive, I think I would  be able to accept fully automatic flight sometime in the future. 

  

 Just not yet.

  

 I recognize that I am old and am happy with current knowledge. It does  allow me to feel comfortable flying a lot of those flying machines that are  "rotting away".

  

 If the new breed of aviators is comfortable flying without the ability to  control their flying machine while in cloud, that is fine with me. 

  

 The venturi powered T&B in my Stearman is very comforting.

  

 You infer that flying a partial panel is difficult. I contend that it is  NOT particularly difficult, IF adequate training has been received.

  

 There is no doubt that the skill is being lost. Most larger airliners lost  their T&Bs almost forty years ago. To my knowledge, none ever had a turn  coordinator.

  

 Chances are that many of the more modern airline pilots would have a  problem flying with the basic needle ball and airspeed.

  

 I contend that the skill is relatively easy to attain ... IF the skill is  desired!

  

 You very correctly stated that a skill not exercised tends to be lost. One  of the reasons I like the T&B over the TC is because I find it relatively  easy to integrate into my basic scan. I do so by using the T&B to check my  rate of turn even though basic attitude reference is being obtained from an  artificial horizon. This day and age, rate of turn is not regularly considered,  but by keeping the rate of turn in mind, I force myself to include the T&B  in my normal scan which makes it much easier for me to use should a failure  occur.

  

 You make reference to my background as a professional pilot. 

  

 I agree that I have had an opportunity that not every pilot has,  needs, or wants. However, I have also been a flight instructor for  fifty-eight years and in those fifty-eight years have trained many an  instrument pilot. Not all of them have retained their partial panel skills, but  many have!

  

 I do not contend that my way is the only way, just that it is a useful  way.

  

 I see that I have wandered all over the landscape where the original intent  was to suggest a low cost source of vacuum to someone who was looking for such a  source.

  

 Once again, my lack of education has done me in,  --- but I am having  fun!

  

 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 3/3/2007 11:24:12 P.M. Central Standard Time,  nuckollsr(at)cox.net writes:

  	  Quote: 	
		  -->    AeroElectric-List message posted by: "Robert L. Nuckolls, III"    <nuckollsr(at)cox.net>



 	  Quote: 	
		  At 09:23 PM 3/3/2007 -0500, you    wrote:


	


 	  Quote: 	
		  Good Evening Bob,


	


 	  Quote: 	
		  May I take that to mean that    you would want a GPS aided wing leveler in a 

Stearman?,
	


 	  Quote: 	
		  Piper Cub?,    Luscombe?, Cessna 140? Cessna 172, Beech Musketeer?,

Beech Bonanza?    North American AT-6? Twin Beech?


	


   Sure, why not? The answer    is simple for most owners

   but for myself, I wouldn't own one    of those airplanes

   because I need to stand in line at too many    windows

   begging permission to make it better.



 	  Quote: 	
		  Where    would you draw the line? All of the above? None of the

above? Some of    the above?


	


   You have just illuminated the reason that those    airplanes

   are all rotting away never to be replaced.  The    GPS

   aided wing leveler is mechanically no more difficult    to

   install in one of those airplanes than in an RV.    But

   those who claim to know more about what's good for    us

   have become the mill-stones between which those    airplanes

   are slowly turning to dust.



 	  Quote: 	
		  I have never    flown any airplane that had a GPS aided wing lever

though I have flown    and owned plenty that did have wing levelers.

We all have to make    individual decisions on what we feel meets our

individual level of    risk, but requiring a GPS aided wing leveler

is not real high on my    list of necessities. Interesting that you

think such a device is    imperative.


	


   Depends on what your design goals are. For    most of the

   the folks on this List, reducing cost of ownership    is

   a goal. Dependency on a T&B traded for dependency    on

   a GPS aided wing leveler offers a lower cost of    ownership

   over the lifetime of the airplane.



 	  Quote: 	
		  Just    goes to show, there is a wide range of desires among us    all.


	


   If the "desire" is to minimize the probability of    an

   unhappy ending to a piece of equipment failing,    then

   the design goals are pretty clear.  I've watched    the

   conversations here on the List and elsewhere    for

   over a decade that vigorously debated the value    of

   this technique or piece of equipment over that . .    .

   But seldom did the conversation recommend    reversion

   modes that reduce, not increase pilot    workload.



   I'm dead-nuts serious about the admonition in    my

   signature tag . . . an exceedingly small number of    pilots

   accomplish daily practice for standard (much less    reversion)

   modes flight in IMC. I understand that you may be    personally

   comfortable . . . and perhaps world class in skills    and

   willingness to fly through clouds with the venerable    tools

   of yesteryear. I've done it too. But I cannot in    good

   conscience recommend that the neophyte builder    embrace

   these techniques today when there are better options    that

   are cheap as a percentage of the total cost of    acquiring,

   owning and operating an    airplane.



   In a cost-of-ownership accounting, the    venturi-driven

   T&B offered as a gift will be more    expensive in $time$

   expended than what's needed to install the    modern alternative.

   Further, the GPS aided wing leveler adds    value to a

   high percentage of every flight while the T&B    is useful

   for calibrating your rudder pressure on    climb-out,

   setting rudder trim, and being there to assist with    the

   management of a failure that you hope will never come    but

   demands a perpetual investment of $time$ to make    sure

   you are ready when it does.



   Very few    of us are professional pilots. Those of us

   who are should be    mindful of advice which presumes that

   all listeners are    interested in (or even capable of) achieving

   levels of    proficiency needed to avoid quantum jumps

   in risk after    certain failures.  This isn't about a "wide

   range of    desires" but simple failure modes effects analysis

   in a market    place where the pilots come with a wide range

   of capability    and willingness to spend $time$ necessary

   to level the risks    if not lower them.



   One of the reasons why I see an    opportunity for OBAM aviation

   to excel in accident reduction    is because we can readily

   take advantage of modernization    opportunities for reducing

   workload without begging anyone's    permission.



   When the GPS aided wing leveler is present,    failure of the

   primary display does not generate an immediate    need

   to revert to a whole new mode of flying.  When one    is

   depending on primary attitude displays to stay    upright,

   then reversion to N/B/AS aviating at the same level    of risk

   demands and investment of $time$ for maintenance    of

   proficiency. The GPS aided wing leveler will hold track    to

   within a degree or so all day, every day and doesn't need    a

   bit of practice to stay "world class" at the    task.



        Bob . . .

	


 



  



AOL now offers free email to everyone.  Find out more about what's free from AOL at AOL.com. 

  [quote][b]

nuckollsr(at)cox.net
Guest

Posted: Sun Mar 04, 2007 8:43 am Post subject: Backup Electric Vacuum Pump

At 09:20 AM 3/4/2007 -0500, you wrote:



 	  Quote: 	
		  Good Morning 'Lectric Bob,



Thank you for the very complete analysis of my position on the validity of 

using a T&B and venturi as a low cost back up to whatever else is deemed 

desirable in a flying machine.



I have been reading your freely presented views since the days when the 

connection was from Down By The Riverside Press. (or, something close to that)



Always a pleasure and your writings are always able to jiggle some thought 

out of my very uneducated brain.



Nevertheless, I do think my responses have some merit.



The original question that started this particular string had to do with 

providing a low cost source of vacuum.



The Venturi is a low cost option.


	


   No argument.



 	  Quote: 	
		  

It is susceptible to icing, but when placed in a warm airstream behind the 

engine it has been shown to handle ice quite well. Vacuum pumps do fail. 

Especially the modern dry pumps if they are not replaced or serviced in 

accordance with the manufacturers instructions.



I still think the venturi is a viable option.


	


  Also no argument.



 	  Quote: 	
		  

I recognize that you cannot take the time to read everything on this list. 

However, I think you would find that I have always said that I will 

happily embrace a newer technology whenever it fits my needs (and my price 

point!). There is nothing I would like better than having a solid state 

autopilot that would be reliable enough such that I did not have to know 

how to fly by instruments to be able to operate in cloud.



If I were to be dropped in the wilderness with nothing to sustain me, I 

would surely die. Many of my ancestors would have been able to survive in 

those same conditions.



Having accepted modern conveniences to keep me alive, I think I would be 

able to accept fully automatic flight sometime in the future.



Just not yet.


	


   Which IS your preference . . .



 	  Quote: 	
		  

I recognize that I am old and am happy with current knowledge. It does 

allow me to feel comfortable flying a lot of those flying machines that 

are "rotting away".



If the new breed of aviators is comfortable flying without the ability to 

control their flying machine while in cloud, that is fine with me.



The venturi powered T&B in my Stearman is very comforting.



You infer that flying a partial panel is difficult. I contend that it is 

NOT particularly difficult, IF adequate training has been received.


	


   "IF" is the operative word here . . .



 	  Quote: 	
		  

There is no doubt that the skill is being lost. Most larger airliners lost 

their T&Bs almost forty years ago. To my knowledge, none ever had a turn 

coordinator.



Chances are that many of the more modern airline pilots would have a 

problem flying with the basic needle ball and airspeed.



I contend that the skill is relatively easy to attain ... IF the skill is 

desired!



You very correctly stated that a skill not exercised tends to be lost. One 

of the reasons I like the T&B over the TC is because I find it relatively 

easy to integrate into my basic scan. I do so by using the T&B to check my 

rate of turn even though basic attitude reference is being obtained from 

an artificial horizon. This day and age, rate of turn is not regularly 

considered, but by keeping the rate of turn in mind, I force myself to 

include the T&B in my normal scan which makes it much easier for me to use 

should a failure occur.



You make reference to my background as a professional pilot.



I agree that I have had an opportunity that not every pilot has, needs, or 

wants. However, I have also been a flight instructor for fifty-eight years 

and in those fifty-eight years have trained many an instrument pilot. Not 

all of them have retained their partial panel skills, but many have!



I do not contend that my way is the only way, just that it is a useful way.



I see that I have wandered all over the landscape where the original 

intent was to suggest a low cost source of vacuum to someone who was 

looking for such a source.



Once again, my lack of education has done me in,  --- but I am having fun!


	


    That's what it's all about. Fun and risk reduction.

    You've offered nothing that's arguable. Nor have I.

    You've encouraged new builders to take advantage of

    a system that has a exceedingly low initial cost and

    if they're willing to do the investment of $time$ for

    training and sustaining the skill, it's one option.



    My approach is that of a systems integrator where

    the pilot is a close second place behind the airframe

    in the study of need for reliability in flight system

    components.



    I have observed first-hand how a pilot who took all the

    courses, spent a lot of time in his airplane, and outfitted

    it with everything you and I both would recommend . . .

    except a stand alone wing-leveler that would back up

    the very expensive system that proved to have

    vulnerabilities. Still, the mechanical failures he

    was presented with should have been no big deal . . .

    except that he experienced a real upset in the clouds and

    upon recovery he no doubt had a cabin full of excited

    passengers. Then while wrestling with the unbelievable

    fact that all this $high$ stuff with backups on top

    of backups was behaving in unanticipated, unpracticed

    ways he needed to revert to an alternate mode of

    flying the airplane. It's a situation that is exceedingly

    difficult to train for.



    I presume that a goodly number of our brothers are

    building airplanes they intend to use for point-A

    to point-B transportation.  On long legged trips the

    probability of encountering less than clear weather

    is higher . . . and the possibilities for having

    company in the cabin goes up. This paints a different

    situation than one experiences while under the hood

    with a pilot riding shotgun who can SEE what's really

    going on. The shape of the airframe/pilot performance

    limits envelope is different, variable and many features

    cannot be anticipated.



    If one EXPECTS to bore holes in clouds and wants the

    minimum cost of ownership for a reversion mode of

    flight management where the risks are on a par with

    flight by stable gyro presentations, then a wing

    leveler is THE solution.  My personal vision of the

    ideal machine for poking around in the fog has dual

    wing levelers with a failure monitor system. This

    suit of hardware would be expected to do ALL handling

    of the ailerons while in IMC.  Then I can leave all

    the presentations off the panel because they're no

    longer needed and the cost of ownership for having

    them goes to zero.



    Over the lifetime of the airplane where I would

    expect to spend less than a few percent of total

    flight time in IMC, the dual wing-leveler system

    offers exceedingly low $ownership$ and risk compared to

    the legacy systems the gray-beards have grown

    up with.



    That doesn't mean others among us shouldn't embrace

    and even enjoy owning and operating a legacy system.

    It's a matter of design goals. If one enjoys

    stalking game with a bow and arrow and the risk of

    going hungry is low or immaterial, great. But if one needs

    to provide food for himself and perhaps others . . .

    and technology enhanced tools for harvesting game

    are available, then the optimum choice is clear.



    If a builder is considering N/B/AS referenced flight

    as a backup for "safe" flight, then he/she must

    be anticipating some willingness (or accidental

    probability) for venturing into clouds. So no

    matter how good you, I or anyone else is with

    the legacy flight instrumentation systems, we are

    remiss in our duties as teachers if we do not

    explain all of TODAY'S options and assist the readers in

    understanding requirements for getting a low risk

    return on the cost of ownership.



    The low cost installation commits one to a future

    investment of $time$ that should be fully explained

    while the builder is still in the decision making phase

    and before hardware is purchased and holes cut

    in the panel. This isn't about anyone else's levels

    of skill or personal preferences. It's a study of

    return on investment and options for real risk reduction.



    Bob . . .

N6030X(at)DaveMorris.com
Guest

Posted: Sun Mar 04, 2007 9:25 am Post subject: Backup Electric Vacuum Pump

I'll throw another variable into the equation.  Under the heading of 

"GPS ain't no guarantee neither"...



Yesterday while flying Eastbound under the floor of the rather 

complex Class B airspace north of Dallas, my GPS suddenly said "No 

Sat", and flopped over on its back.  I figured it was just a quick 

"blink" and kept flying.  It stayed offline.  I flew a 360 to see if 

it would reaquire on any other satellites, but it didn't.  I rebooted 

it.  I rebooted the PDA it was hooked to.  I rebooted the WX Worx 

box.  I checked the power lights.  (All while staying upright and 

without busting the Class B).



Since I was trying to get from Dallas to Shreveport, I powered up my 

backup Loran and looked up a few VORs while I was at it.  Then I used 

the Loran to give me the distance from the Addison airport whose 

airspace I also needed to stay out of.  Finally, I decided I had time 

to go land at McKinney and figure out what was wrong with the GPS, 

and at that instant, it came back online and stayed that way all the 

way to Shreveport and back.



What I neglected to try was powering off my COM radios, since there 

are reports that some local oscillator frequencies interfere with GPS 

under certain conditions.  I didn't have the luxury of powering off 

my transponder, since I was deep inside the Mode C circle.  But 

here's a case where high technology failed and it was a good thing to 

have a backup.



Dave Morris

At 10:41 AM 3/4/2007, you wrote:

 	  Quote: 	
		  

<nuckollsr(at)cox.net>



At 09:20 AM 3/4/2007 -0500, you wrote:



>Good Morning 'Lectric Bob,

>

>Thank you for the very complete analysis of my position on the 

>validity of using a T&B and venturi as a low cost back up to 

>whatever else is deemed desirable in a flying machine.

>

>I have been reading your freely presented views since the days when 

>the connection was from Down By The Riverside Press. (or, something 

>close to that)

>

>Always a pleasure and your writings are always able to jiggle some 

>thought out of my very uneducated brain.

>

>Nevertheless, I do think my responses have some merit.

>

>The original question that started this particular string had to do 

>with providing a low cost source of vacuum.

>

>The Venturi is a low cost option.



   No argument.



>

>It is susceptible to icing, but when placed in a warm airstream 

>behind the engine it has been shown to handle ice quite well. 

>Vacuum pumps do fail. Especially the modern dry pumps if they are 

>not replaced or serviced in accordance with the manufacturers instructions.

>

>I still think the venturi is a viable option.



  Also no argument.



>

>I recognize that you cannot take the time to read everything on 

>this list. However, I think you would find that I have always said 

>that I will happily embrace a newer technology whenever it fits my 

>needs (and my price point!). There is nothing I would like better 

>than having a solid state autopilot that would be reliable enough 

>such that I did not have to know how to fly by instruments to be 

>able to operate in cloud.

>

>If I were to be dropped in the wilderness with nothing to sustain 

>me, I would surely die. Many of my ancestors would have been able 

>to survive in those same conditions.

>

>Having accepted modern conveniences to keep me alive, I think I 

>would be able to accept fully automatic flight sometime in the future.

>

>Just not yet.



   Which IS your preference . . .



>

>I recognize that I am old and am happy with current knowledge. It 

>does allow me to feel comfortable flying a lot of those flying 

>machines that are "rotting away".

>

>If the new breed of aviators is comfortable flying without the 

>ability to control their flying machine while in cloud, that is fine with me.

>

>The venturi powered T&B in my Stearman is very comforting.

>

>You infer that flying a partial panel is difficult. I contend that 

>it is NOT particularly difficult, IF adequate training has been received.



   "IF" is the operative word here . . .



>

>There is no doubt that the skill is being lost. Most larger 

>airliners lost their T&Bs almost forty years ago. To my knowledge, 

>none ever had a turn coordinator.

>

>Chances are that many of the more modern airline pilots would have 

>a problem flying with the basic needle ball and airspeed.

>

>I contend that the skill is relatively easy to attain ... IF the 

>skill is desired!

>

>You very correctly stated that a skill not exercised tends to be 

>lost. One of the reasons I like the T&B over the TC is because I 

>find it relatively easy to integrate into my basic scan. I do so by 

>using the T&B to check my rate of turn even though basic attitude 

>reference is being obtained from an artificial horizon. This day 

>and age, rate of turn is not regularly considered, but by keeping 

>the rate of turn in mind, I force myself to include the T&B in my 

>normal scan which makes it much easier for me to use should a failure occur.

>

>You make reference to my background as a professional pilot.

>

>I agree that I have had an opportunity that not every pilot has, 

>needs, or wants. However, I have also been a flight instructor for 

>fifty-eight years and in those fifty-eight years have trained many 

>an instrument pilot. Not all of them have retained their partial 

>panel skills, but many have!

>

>I do not contend that my way is the only way, just that it is a useful way.

>

>I see that I have wandered all over the landscape where the 

>original intent was to suggest a low cost source of vacuum to 

>someone who was looking for such a source.

>

>Once again, my lack of education has done me in,  --- but I am having fun!



    That's what it's all about. Fun and risk reduction.

    You've offered nothing that's arguable. Nor have I.

    You've encouraged new builders to take advantage of

    a system that has a exceedingly low initial cost and

    if they're willing to do the investment of $time$ for

    training and sustaining the skill, it's one option.



    My approach is that of a systems integrator where

    the pilot is a close second place behind the airframe

    in the study of need for reliability in flight system

    components.



    I have observed first-hand how a pilot who took all the

    courses, spent a lot of time in his airplane, and outfitted

    it with everything you and I both would recommend . . .

    except a stand alone wing-leveler that would back up

    the very expensive system that proved to have

    vulnerabilities. Still, the mechanical failures he

    was presented with should have been no big deal . . .

    except that he experienced a real upset in the clouds and

    upon recovery he no doubt had a cabin full of excited

    passengers. Then while wrestling with the unbelievable

    fact that all this $high$ stuff with backups on top

    of backups was behaving in unanticipated, unpracticed

    ways he needed to revert to an alternate mode of

    flying the airplane. It's a situation that is exceedingly

    difficult to train for.



    I presume that a goodly number of our brothers are

    building airplanes they intend to use for point-A

    to point-B transportation.  On long legged trips the

    probability of encountering less than clear weather

    is higher . . . and the possibilities for having

    company in the cabin goes up. This paints a different

    situation than one experiences while under the hood

    with a pilot riding shotgun who can SEE what's really

    going on. The shape of the airframe/pilot performance

    limits envelope is different, variable and many features

    cannot be anticipated.



    If one EXPECTS to bore holes in clouds and wants the

    minimum cost of ownership for a reversion mode of

    flight management where the risks are on a par with

    flight by stable gyro presentations, then a wing

    leveler is THE solution.  My personal vision of the

    ideal machine for poking around in the fog has dual

    wing levelers with a failure monitor system. This

    suit of hardware would be expected to do ALL handling

    of the ailerons while in IMC.  Then I can leave all

    the presentations off the panel because they're no

    longer needed and the cost of ownership for having

    them goes to zero.



    Over the lifetime of the airplane where I would

    expect to spend less than a few percent of total

    flight time in IMC, the dual wing-leveler system

    offers exceedingly low $ownership$ and risk compared to

    the legacy systems the gray-beards have grown

    up with.



    That doesn't mean others among us shouldn't embrace

    and even enjoy owning and operating a legacy system.

    It's a matter of design goals. If one enjoys

    stalking game with a bow and arrow and the risk of

    going hungry is low or immaterial, great. But if one needs

    to provide food for himself and perhaps others . . .

    and technology enhanced tools for harvesting game

    are available, then the optimum choice is clear.



    If a builder is considering N/B/AS referenced flight

    as a backup for "safe" flight, then he/she must

    be anticipating some willingness (or accidental

    probability) for venturing into clouds. So no

    matter how good you, I or anyone else is with

    the legacy flight instrumentation systems, we are

    remiss in our duties as teachers if we do not

    explain all of TODAY'S options and assist the readers in

    understanding requirements for getting a low risk

    return on the cost of ownership.



    The low cost installation commits one to a future

    investment of $time$ that should be fully explained

    while the builder is still in the decision making phase

    and before hardware is purchased and holes cut

    in the panel. This isn't about anyone else's levels

    of skill or personal preferences. It's a study of

    return on investment and options for real risk reduction.



    Bob . . .

Bill Denton

Joined: 10 Jan 2006
Posts: 97
Location: Chicago, IL USA

Posted: Sun Mar 04, 2007 1:13 pm Post subject: Backup Electric Vacuum Pump

Probably not relevant to this specific problem, but worth noting...



In the installation manuals for Garmin's 400W and 500W series units, it

states the following:



"Ground-based cell phones that are on, even in a monitoring state, can

disrupt GPS performance."



I know there have been all sorts of nebulous warnings floating around from

time to time, but this is the first specific one I've seen.



Hope it's useful to some of you guys...

--

N6030X(at)DaveMorris.com
Guest

Posted: Sun Mar 04, 2007 4:05 pm Post subject: Backup Electric Vacuum Pump

That's a very interesting point, because it was the one time I've 

flown in the past 5 months where I accidentally left my cellphone 

turned on in my coat pocket all the way in the baggage compartment 

and couldn't reach it, so I just left it alone.  Hmmmmmmmm



Dave Morirs



At 03:12 PM 3/4/2007, you wrote:

[quote]



Probably not relevant to this specific problem, but worth noting...



In the installation manuals for Garmin's 400W and 500W series units, it

states the following:



"Ground-based cell phones that are on, even in a monitoring state, can

disrupt GPS performance."



I know there have been all sorts of nebulous warnings floating around from

time to time, but this is the first specific one I've seen.



Hope it's useful to some of you guys...

--

bobf(at)feldtman.com
Guest

Posted: Sun Mar 04, 2007 5:23 pm Post subject: Backup Electric Vacuum Pump

Remember - the feds can turn off the GPS system with any perceived 

threat - so I'd be careful about pure IMC in an A/C where GPS is only 

source of data. I noted it was "down" during the Super bowl.



bobf

Dave N6030X wrote:

[quote] 

 <N6030X(at)DaveMorris.com>



 That's a very interesting point, because it was the one time I've 

 flown in the past 5 months where I accidentally left my cellphone 

 turned on in my coat pocket all the way in the baggage compartment and 

 couldn't reach it, so I just left it alone.  Hmmmmmmmm



 Dave Morirs



 At 03:12 PM 3/4/2007, you wrote:

> 

> <bdenton(at)bdenton.com>

>

> Probably not relevant to this specific problem, but worth noting...

>

> In the installation manuals for Garmin's 400W and 500W series units, it

> states the following:

>

> "Ground-based cell phones that are on, even in a monitoring state, can

> disrupt GPS performance."

>

> I know there have been all sorts of nebulous warnings floating around 

> from

> time to time, but this is the first specific one I've seen.

>

> Hope it's useful to some of you guys...

> --

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