Standby Vacuum?

[Mitty]

Our club is looking at upgrading a couple of airplanes to Garmin 430s, etc.

It seems to me that standby vacuum would be a good thing to add, too.

1) Good idea? Do these systems really work?

2) Recommendations on type/brand/model?

TIA

[Michael]

What kind of airplanes do you have? I can understand wanting attitude
indication redundancy in a Bonanza, but it's overkill on a Skyhawk.

Do you have redundant attitude gyros? I've seen more of those fail
than dry pumps, never mind wet.

There are two basic approaches - tapping the intake manifold (which
means full throttle is no longer available if you want vacuum), and an
electrically driven backup pump (which adds weight). Decide whether
you want to carry the extra weight around all the time, or whether you
want to limit yourself to partial power when the vacuum fails. Both
systems work.

I think that if you really feel the need for redundancy, the sensible
solution is replacing the T&B with an electric AI.

Michael

[Dave Butler]

Mitty wrote:
> Our club is looking at upgrading a couple of airplanes to Garmin 430s, etc.
>
> It seems to me that standby vacuum would be a good thing to add, too.
>
> 1) Good idea? Do these systems really work?
>
> 2) Recommendations on type/brand/model?

- based on manifold vacuum, like Precise Flight: Inexpensive. Requires some
pilot training. Shuttle valve requires eventual maintenance. Even with training,
you might be surprised when you lose vacuum under some flight conditions (like
during a go-around). They work best when descending, stop working as you add power.

- separate electrically driven vacuum pump: heavy and expensive, but reliable.
Seamless operation. Turn it on and interpret all the gauges same as always.

- electrically driven attitude indicator: the models I know about have been
known to have quality problems, short life, frequent repair. Questionable value
if not in your scan (many seem to mount them on the copilot side).

- GPS with a pseudo-panel, like some of the recent Garmins: Might be OK in a
172-class aircraft. For faster and slipperier aircraft, I question whether
current models update fast enough to keep you out of trouble.

- solid-state gyros in a portable device: never seen one of these so I can't
comment, but some people are enthusiastic about them.

Did I miss any categories?

Dave

[Peter R.]

Michael > wrote:

> I think that if you really feel the need for redundancy, the sensible
> solution is replacing the T&B with an electric AI.

I see that Sporty's is encouraging this option, too, with their electric
AI.

However, doesn't the AI have the potential to tumble in an unusual
attitude? During my IFR training I recall learning that the turn
coordinator will not tumble in an unusual attitude scenario whereas the AI
may. Since recovery from an unusual attitude was taught to me by first
going to the TC, I would be hesitant to replace an instrument so reliable
during a UA.

What say you?

--
Peter
























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[Scott Moore]

Mitty wrote:
> Our club is looking at upgrading a couple of airplanes to Garmin 430s, etc.
>
> It seems to me that standby vacuum would be a good thing to add, too.
>
> 1) Good idea? Do these systems really work?
>
> 2) Recommendations on type/brand/model?
>
> TIA

Electric attitude. Vacuum pumps are going away.

[Andrew Gideon]

Scott Moore wrote:

> Electric attitude. Vacuum pumps are going away.

Or electronic AI (ie. solid state; not a gyro).

My club's fleet all have what used to be the precise flight standby vacuum.
It's not bad, but I'd prefer something else.

One important consideration is preflight. Be sure that you follow the
procedure, lest you find yourself in the clouds with no backup and no
awareness that you've no backup.

- Andrew

[Michael]

> However, doesn't the AI have the potential to tumble in an unusual
> attitude?

You know, I've heard that too. And it sure seems like it could, by
design. Only thing is, I've spent a lot of time teaching unusual
attitudes - and I've never seen it happen. I think you need something
more radical to happen than what we think of as an unusual attitude -
more aerobatic.

I see little chance of that happening with dual AI's, and even less
chance that the average pilot will recover from an aerobatic attitude
partial panel after screwing up enough to get into that mess.

But hey - if you have the panel room, why not keep the electric TC too?

Michael

[Peter R.]

Michael > wrote:

> I see little chance of that happening with dual AI's, and even less
> chance that the average pilot will recover from an aerobatic attitude
> partial panel after screwing up enough to get into that mess.

Interesting that you pointed that out. I was thinking the same thing when
I posed the question but thought that two tumbling AIs would pretty much
guarantee that the pilot would not recover.

> But hey - if you have the panel room, why not keep the electric TC too?

My Bonanza has the original TC along with a backup electric AI located to
the left of the TC. However, the electric AI keeps precessing and requires
a reset about four times per hour, which concerns me.

--
Peter
























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[Jose]

> I think that if you really feel the need for redundancy, the sensible
> solution is replacing the T&B with an electric AI.

I would not remove the T&B. If you add another AI, put it in a nearby
hole, but not the T&B. No other instrument provides turn rate information.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Mitty]

Airplanes: We have 4 different flavors of PA-28s, six total, plus a Cherokee
Six. The two being upgraded right now are Archers.

Type of Flying: We do not fly a lot of hard IFR, panel space is limited as is
money. Hence, we are not looking at backup horizons, etc. Also, one of the
airplanes will be getting an S-TEC 2/ or 30, which replaces the TC.

Hence, something like the Precise Flight at $400-500 kind of numbers is the
candidate. Possibly an electric pump, though I don't know anything about the cost.

On 8/17/2005 12:41 PM, Mitty wrote the following:
> Our club is looking at upgrading a couple of airplanes to Garmin 430s, etc.
>
> It seems to me that standby vacuum would be a good thing to add, too.
>
> 1) Good idea? Do these systems really work?
>
> 2) Recommendations on type/brand/model?
>
> TIA

[Andrew Gideon]

Mitty wrote:

> WeÂ*doÂ*notÂ*flyÂ*aÂ*lotÂ*ofÂ*hardÂ*IFR

That's good. My "scary thought" about the precise-flight is losing vacuum
pressure on the missed approach.

- Andrew

[Bob Moore]

Jose > wrote
> I would not remove the T&B. If you add another AI, put it in a nearby
> hole, but not the T&B. No other instrument provides turn rate
> information.

After 47 years of civilian, military, and airline flying, I have
yet to see a reason for "turn rate" as long as I have a functioning
attitude indicator.

Bob Moore

[Dave Butler]

Mitty wrote:
> Airplanes: We have 4 different flavors of PA-28s, six total, plus a
> Cherokee Six. The two being upgraded right now are Archers.
>
> Type of Flying: We do not fly a lot of hard IFR, panel space is limited
> as is money. Hence, we are not looking at backup horizons, etc. Also,
> one of the airplanes will be getting an S-TEC 2/ or 30, which replaces
> the TC.
>
> Hence, something like the Precise Flight at $400-500 kind of numbers is
> the candidate. Possibly an electric pump, though I don't know anything
> about the cost.

I once owned an Archer that was leased to a flying club, and I installed the
Precise Flight system. I wouldn't do it again. I *might* feel differently if I
were the only pilot, but probably not.

Pilots need to understand how it works and be prepared to accommodate its
peculiarities. The peculiarities can be explained in a few paragraphs, but won't
be appreciated by the pilots unless they have actually experienced the way it
works. You can't experience the way it works unless you physically disconnect
the vacuum pump, cap it off, and go flying. You can't do that kind of training
for every pilot in the club.

If you think just pulling out the knob is sufficient to experience how it works,
you are mistaken. The result of pulling out the knob is quite different when the
vacuum pump is operating and when it is not operating.

Unless you preflight the system before takeoff, you can't be sure it will work
when you need it.

If you don't exercise the shuttle valve often it can get stuck, rendering the
system inoperative and requiring extra maintenance. You exercise the shuttle
valve every time you do the preflight checks, *if* you do the preflight checks
correctly. I found most pilots didn't understand how to do the preflight checks
correctly, didn't follow a written checklist, and often failed to preflight the
system at all. If they did preflight it, they didn't understand how to do it
correctly so that the shuttle valve is exercised and you know it's working.

In operation, at best, you must reduce engine power (thereby reducing manifold
pressure, or, put another way, increasing manifold vacuum) in order to make the
system work. So if you need to climb, or at some altitudes, even maintain
altitude, you are going to require more power than the reduced amount that will
keep the gyros spinning. So in that circumstance you are going to be partial
panel anyway.

In the high workload environment of say, a missed approach, as you add power,
the gyros start to spin down. That adds another work item to your already high
workload: recognizing that the backup vacuum has "failed". Operating under the
stress of a vacuum pump failure and a missed approach, you might forget that
will inevitably happen as soon as you add power.

In short, IMO you might as well just learn to fly partial panel.

Dave

[Michael]

> Interesting that you pointed that out. I was thinking the same thing when
> I posed the question but thought that two tumbling AIs would pretty much
> guarantee that the pilot would not recover.

I agree with you - with two tumbled AI's and no TC, recovery is
impossible. With a working TC, it is merely highly unlikely.
Therefore, if the panel space is there, it might make sense to keep the
TC. Not much sense, mind you, because if you manage to screw up badly
enough to put the plane into an attitude that would cause both AI's to
tumble, well, I'm willing to give very good odds that you're not going
to recover on the TC.

However, let's say having both the TC and the second (electric) AI is
not practical (probably due to space considerations). Would I rather
have an electric AI, or the TC? I would still prefer the electric AI.
First off, with dual AI's next to each other, I believe that following
a dying AI into an unusual attitude becomes far less likely, and thus
while the chances of recovery from the unusual attitude are reduced
slightly, the chances of encountering it in the first place are reduced
dramatically. Not so with a backup vacuum - you have to engage it.
And even if you do, half the time (in my experience more) the problem
is the AI, not the power source, so backup power for the AI does you no
good.

The problem with this analysis is the reliability (or lack of same) for
electric AI's. I've heard the affordable ones are not good, and the
good ones are not affordable.

Finally, there is the issue of training. If you have dual AI's with
independent power sources, it makes sense to skip partial panel
training. If you have only a single AI, even with redundant power
sources, that's not the case. In that case, a standby vacuum system
seems to be an unjustified expense - the money spent on it is probably
better spent on recurrent training.

Michael

[Maule Driver]

Bob Moore wrote:
> After 47 years of civilian, military, and airline flying, I have
> yet to see a reason for "turn rate" as long as I have a functioning
> attitude indicator.

As a recreational pilot of a simple IFR aircraft, I've recently
discovered a great role for the T&B; staying on heading. After a few
years of struggling to keep my non-AP equipped flivver on a MH, I've
re-discovered what many must know. The T&B is the best instrument to go
straight with. The AI gives you good info, and the heading gyro does
too, but the best way to keep it all centered in my Maule is definitely
the T&B. Especially in calm conditions.

[Maule Driver]

I have the precise flight setup. I've never had the failure where I had
to use it but it gives me peace of mind. So does a new pump.

I'm not familiar with typical IFR setups but do most a/c have a vacuum
failure light to tell you when the vac pump fails? I believe that the
vacuum failure light that was installed with the Precise Flight system
is as valuable, or perhaps more valuable than the actual backup function.

That series of tests where the vac was failed while filming pilots
reactions seem to indicate that the main problem was detecting the
failure and slow roll over of the AI in time. A red light beaming at
you from the center of the panel seems to be to be pretty damn valuable.

But like I said, I haven't had the failure so I just don't know.

Mitty wrote:
> Our club is looking at upgrading a couple of airplanes to Garmin 430s, etc.
>
> It seems to me that standby vacuum would be a good thing to add, too.
>
> 1) Good idea? Do these systems really work?
>
> 2) Recommendations on type/brand/model?
>
> TIA

[Stubby]

Scott Moore wrote:
> Mitty wrote:
>
>>Our club is looking at upgrading a couple of airplanes to Garmin 430s, etc.
>>
>>It seems to me that standby vacuum would be a good thing to add, too.
>>
>>1) Good idea? Do these systems really work?
>>
>>2) Recommendations on type/brand/model?
>>
>>TIA
>
>
> Electric attitude. Vacuum pumps are going away.
>
But, can't an electric attitude indicator fail? Bearings wear out.
I've suffered that on a hard disk. Are there any MTBF numbers for the
two systems?

[Barry]

> Therefore, if the panel space is there, it might make sense to
> keep the TC.

I know that FAR 91.205 requires a rate of turn indicator for IFR (except for
airliners with three attitude indicators). Is it common for this requirement
to be waived to allow substituting a second AI for the TC?

[Michael]

> I know that FAR 91.205 requires a rate of turn indicator for IFR (except for
> airliners with three attitude indicators). Is it common for this requirement
> to be waived to allow substituting a second AI for the TC?

In a manner of speaking. No waiver is actually necessary. Advisory
Circular 91-75 details the conditions under which this substitution is
acceptable. Note that 91.205 states:

no person may operate a powered civil aircraft with a standard category
U.S.
airworthiness certificate in any operation described in paragraphs (b)
through
(f) of this section unless that aircraft contains the instruments and
equipment
specified in those paragraphs (or FAA-approved equivalents)

91.75 Details what constitutes an FAA-approved equivalent for a
rate-of-turn indicator.

Michael

[[email protected]]

Seems that the best redundancy is a rate based autopilot (read STEC).
Since it is based on, and runs on, a turn indicator the issue of
whether yo have a good one is solved. However I still have an electric
backup vacuum pump in my C172.

[[email protected]]

Maule Driver > wrote:
: As a recreational pilot of a simple IFR aircraft, I've recently
: discovered a great role for the T&B; staying on heading. After a few
: years of struggling to keep my non-AP equipped flivver on a MH, I've
: re-discovered what many must know. The T&B is the best instrument to go
: straight with. The AI gives you good info, and the heading gyro does
: too, but the best way to keep it all centered in my Maule is definitely
: the T&B. Especially in calm conditions.

I don't know if I'll agree with that. Once you dial in your wind correction
angle, the DG is the primary instrument for bank in straight-level flying.

When I was working on the instrument written, I tried to find easy ways to
remember primary vs supporting instruments for different stages of flight. One of my
conclusions was that for long-term accuracy, the instruments that provide the integral
of the chosen parameter are the most accurate, and thus "primary." For instance,
the result of a pitch change integrated gives you altitude, so it's primary for
straight-level. The result of a bank change integrated yields a heading, so the DG is
primary.

The trouble with direct-read indications is that they are not accurate enough
for long-term useage. The AI is good for radical attitude changes, but you cannot see
a 1/10 stdrad turn on either it or the T&B/TC. You *will* see it on the DG as the
numbers slows roll by.

Of course, to each their own. Just so long as you keep the shiny-side up!...
:)

-Cory

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[Mark Hansen]

On 8/18/2005 10:49, wrote:

> Maule Driver > wrote:
> : As a recreational pilot of a simple IFR aircraft, I've recently
> : discovered a great role for the T&B; staying on heading. After a few
> : years of struggling to keep my non-AP equipped flivver on a MH, I've
> : re-discovered what many must know. The T&B is the best instrument to go
> : straight with. The AI gives you good info, and the heading gyro does
> : too, but the best way to keep it all centered in my Maule is definitely
> : the T&B. Especially in calm conditions.
>
> I don't know if I'll agree with that. Once you dial in your wind correction
> angle, the DG is the primary instrument for bank in straight-level flying.

Here's another way to think about this.

I've done what Maule Driver is talking about, and think of it rather
like using the VSI to assist in maintaining altitude. I use the VSI
to give me an indication that an altitude change is coming, and I need
to anticipate it and correct (the VSI doesn't react all that quickly,
but still...)

If I do this right, I never see the altitude change. Of course,
this doesn't change the fact that the altimeter is the primary pitch
instrument - it's just not the only pitch instrument.

So ... I do the same with the T&B giving me an indication that a turn
is coming, and I can anticipate it and react. The DG is still the final
authority as to whether or not you're heading in the right direction, but
I think it's better to keep it on the heading, rather than notice it's
not and having to correct (when the turbulence allows, of course ;-) )


>
> When I was working on the instrument written, I tried to find easy ways to
> remember primary vs supporting instruments for different stages of flight. One of my
> conclusions was that for long-term accuracy, the instruments that provide the integral
> of the chosen parameter are the most accurate, and thus "primary." For instance,
> the result of a pitch change integrated gives you altitude, so it's primary for
> straight-level. The result of a bank change integrated yields a heading, so the DG is
> primary.
>
> The trouble with direct-read indications is that they are not accurate enough
> for long-term useage. The AI is good for radical attitude changes, but you cannot see
> a 1/10 stdrad turn on either it or the T&B/TC. You *will* see it on the DG as the
> numbers slows roll by.
>
> Of course, to each their own. Just so long as you keep the shiny-side up!...
> :)
>
> -Cory
>
> ************************************************** ***********************
> * Cory Papenfuss *
> * Electrical Engineering candidate Ph.D. graduate student *
> * Virginia Polytechnic Institute and State University *
> ************************************************** ***********************
>


--
Mark Hansen, PP-ASEL, Instrument Student
Sacramento, CA

[[email protected]]

Mark Hansen > wrote:
: I've done what Maule Driver is talking about, and think of it rather
: like using the VSI to assist in maintaining altitude. I use the VSI
: to give me an indication that an altitude change is coming, and I need
: to anticipate it and correct (the VSI doesn't react all that quickly,
: but still...)

: If I do this right, I never see the altitude change. Of course,
: this doesn't change the fact that the altimeter is the primary pitch
: instrument - it's just not the only pitch instrument.

: So ... I do the same with the T&B giving me an indication that a turn
: is coming, and I can anticipate it and react. The DG is still the final
: authority as to whether or not you're heading in the right direction, but
: I think it's better to keep it on the heading, rather than notice it's
: not and having to correct (when the turbulence allows, of course ;-) )


Sure... they're all related of course. I guess the point I was trying to make
is that (barring turbulence), I don't *see* a change in VSI/AI/T&B in straight/level
cruise. A certain amount of pressure on the controls will fix small errors in DG/ALT.
Those are typical in non-turbulent flight, and there will be no perceptible indication
from the VSI/AI/T&B. For anything other than a minute change (e.g. turbulence) the
other indicators are better and then line up on the "primaries" (DG/ALT).

Like I said... to each their own. Probably saying the same thing anyway... :)

-Cory
--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[Robert M. Gary]

Its a good idea if you can't afford a standby electric attitude
indicator. I've had more indicators fail then pumps myself.

-Robert

[Robert M. Gary]

If your attitude indicator fails and you have a back up, you just look
at the other attitude indicator (this is what the airlines and military
teach).
If your attitude indicator fails and you have precise flight, you learn
to fly with the turn coordinator alone.

-Robert

[Scott Moore]

Peter R. wrote:
> Michael > wrote:
>
>
>>I think that if you really feel the need for redundancy, the sensible
>>solution is replacing the T&B with an electric AI.
>
>
> I see that Sporty's is encouraging this option, too, with their electric
> AI.
>
> However, doesn't the AI have the potential to tumble in an unusual
> attitude? During my IFR training I recall learning that the turn
> coordinator will not tumble in an unusual attitude scenario whereas the AI
> may. Since recovery from an unusual attitude was taught to me by first
> going to the TC, I would be hesitant to replace an instrument so reliable
> during a UA.
>
> What say you?
>

Vacuums tumble.

Saw it on Dave Letterman, "throwing household appliances off a building".

[Scott Moore]

Peter R. wrote:
> Michael > wrote:
>
>
>>I see little chance of that happening with dual AI's, and even less
>>chance that the average pilot will recover from an aerobatic attitude
>>partial panel after screwing up enough to get into that mess.
>
>
> Interesting that you pointed that out. I was thinking the same thing when
> I posed the question but thought that two tumbling AIs would pretty much
> guarantee that the pilot would not recover.
>
>
>>But hey - if you have the panel room, why not keep the electric TC too?
>
>
> My Bonanza has the original TC along with a backup electric AI located to
> the left of the TC. However, the electric AI keeps precessing and requires
> a reset about four times per hour, which concerns me.
>

What brand ?

[Scott Moore]

Stubby wrote:
>
> Scott Moore wrote:
>
>>Mitty wrote:
>>
>>
>>>Our club is looking at upgrading a couple of airplanes to Garmin 430s, etc.
>>>
>>>It seems to me that standby vacuum would be a good thing to add, too.
>>>
>>>1) Good idea? Do these systems really work?
>>>
>>>2) Recommendations on type/brand/model?
>>>
>>>TIA
>>
>>
>>Electric attitude. Vacuum pumps are going away.
>>
>
> But, can't an electric attitude indicator fail? Bearings wear out.
> I've suffered that on a hard disk. Are there any MTBF numbers for the
> two systems?

I have heard that EAIs have better fail numbers than vac, but sure, its
nonzero.

The reason why all electric panels are becoming common is because
electrical systems are more reliable than vacuum, and backup is easier to
provide for everything, a second battery. It also makes more sense to
unify around a single system, instead of having a hodge-podge of two
different systems.

I would go all electric and remove my vac pump, but I blew it and
got an NSD-360. The first repair bill for that utter piece of defective
junk easily pushed the total cost above what an all electric solution
would have cost (i.e., $5000 for the NSD360, and $4000 to get it to
work correctly).

[Scott Moore]

wrote:
> Seems that the best redundancy is a rate based autopilot (read STEC).
> Since it is based on, and runs on, a turn indicator the issue of
> whether yo have a good one is solved. However I still have an electric
> backup vacuum pump in my C172.
>

I really believe this. The TC won't tumble. It comes down to two things:

1. If you have the presence of mind to engage the AP if the AI goes south.
Of course, in most IFR situations, the chances are good the AP is already
on.

2. Although the standard "ethic" says that engaging the AP during a loss
of control is a good idea, I tend to doubt it. The STEC has limits on what
control pressures it will tolerate, and the result can be for it to
simply disengage if it cannot overcome them.

[[email protected]]

Peter > wrote:
: It took me a while to work out what the FAA was looking for in the IR
: written, on "primary" and "supporting". It's easy enough in straight
: and level flight, but on stuff like a transition from a stabilised
: level turn to a climbing constant-speed turn, it's very hard to get
: one's head around it. Luckily, I passed, and one has to learn these
: word tricks only once :)
:

Yeah, me too... that's why I came up with what I did (in my own mind, anyway).
Basically, it was something like:
attitude => rate => result

So, during the phases of flight while you are transitioning, the attitude is
generally the most important. Holding rates (CR climb, SR turn, etc) it's
rate-based
like VSI or TC. Result is the integral thing.

Anyway, I agree... I passed and now you just need to know how to do it, not
some cryptic wordplay to pass an exam.

-Cory


************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[[email protected]]

: The reason why all electric panels are becoming common is because
: electrical systems are more reliable than vacuum, and backup is easier to
: provide for everything, a second battery. It also makes more sense to
: unify around a single system, instead of having a hodge-podge of two
: different systems.

Easier is relative. Designing a truly redundant electrical system is
nontrivial and expensive in both money, weight, and complexity. Strictly speaking,
you should have dual alternators, dual busses with crossover breakers, etc, etc. It's
not as simple as "throwing another battery" in the tail. If the system isn't designed
properly or is improperly operated, a failed system can break the other system.

The nice thing about the standard six-pack is that there's redundancy built
into the instruments and sources. Yes, vacuum systems are less reliable, but short of
something catastrophic, they are *completely* independent. It would probably be
better to transition to an electric AI and vacuum TC as "standard equipment"... or
maybe electric DG and vacuum TC. Still redundancy, but the likelihood of failure goes
down with the electric replacements. A vac pump going out on a standard plane (and
losing *all* bank except TC) is "unpleasant" and not that uncommon. Change 2 out of 3
bank instruments to be electric, rather than vacuum and one failure isn't nearly so
bad.

-Cory

--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[Maule Driver]

I never did get that whole primary secondary stuff to stick in my brain.
Let alone integration...

Obviously, we all have to scan to keep it all on track. No one has ever
figured out a universally applicable optimal procedure for scanning.
And I guess only eyeball scanning will ever tell us what one actually does.

Anyway, after reading several anecdotal references to increased use of
the T&B, I tried it. It worked. Specifically when hand flying the
trimmed out Maule.

Next time you droning along, trimmed out, with Ralph or Bob or whatever
his name is turned off, replace your use of the AI with the TC. Of
course the DG tells you how you are doing and which way to correct, but
try flying with the TC only for longer than you would normally. The
experience changed my scan.

I think Collins wrote something recently where someone was hand flying
on instruments from the right seat. They couldn't see the AI well so
they used the TC instead. Collins had to comment that they were
smoother and straighter than usual and the reason given was use of the TC.

wrote:
> ...the AI gives you good info, and the heading gyro does
> : too, but the best way to keep it all centered in my Maule is definitely
> : the T&B. Especially in calm conditions.
>
> I don't know if I'll agree with that. Once you dial in your wind correction
> angle, the DG is the primary instrument for bank in straight-level flying.
>
> When I was working on the instrument written, I tried to find easy ways to
> remember primary vs supporting instruments for different stages of flight. One of my
> conclusions was that for long-term accuracy, the instruments that provide the integral
> of the chosen parameter are the most accurate, and thus "primary." For instance,
> the result of a pitch change integrated gives you altitude, so it's primary for
> straight-level. The result of a bank change integrated yields a heading, so the DG is
> primary.
>
> The trouble with direct-read indications is that they are not accurate enough
> for long-term useage. The AI is good for radical attitude changes, but you cannot see
> a 1/10 stdrad turn on either it or the T&B/TC. You *will* see it on the DG as the
> numbers slows roll by.
>
> Of course, to each their own. Just so long as you keep the shiny-side up!...
> :)
>
> -Cory
>
> ************************************************** ***********************
> * Cory Papenfuss *
> * Electrical Engineering candidate Ph.D. graduate student *
> * Virginia Polytechnic Institute and State University *
> ************************************************** ***********************
>

[Jose]

> Next time you droning along, trimmed out, with Ralph or Bob or whatever his name is turned off, replace your use of the AI with the TC. Of course the DG tells you how you are doing and which way to correct, but try flying with the TC only for longer than you would normally. The experience changed my scan.

I don't know why, but I never did use the AI much. I rely on the TC,
altimiter, DG, and airspeed to give me my picture, and leave the AI sort
of in the background. As a result, when the AI is covered, I fly
equally well. One CFI commented that I fly better on partial panel then
on the full panel.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Roy Smith]

Jose > wrote:
>> Next time you droning along, trimmed out, with Ralph or Bob or
>whatever his name is turned off, replace your use of the AI with the TC.
>Of course the DG tells you how you are doing and which way to correct,
>but try flying with the TC only for longer than you would normally. The
>experience changed my scan.
>
>I don't know why, but I never did use the AI much. I rely on the TC,
>altimiter, DG, and airspeed to give me my picture, and leave the AI sort
>of in the background. As a result, when the AI is covered, I fly
>equally well. One CFI commented that I fly better on partial panel then
>on the full panel.

I have much the same experience. My instrument instructor was a nut
for partial panel practice, so I got really good at it. I miss the DG
when it's covered up, but for the most part, I fly the TC for bank and
the ASI for pitch.

After all these years, I honestly can't tell you how many bars up it
takes to get Vy or what bank angle it takes for a standard rate turn.

[[email protected]]

Roy Smith > wrote:
: >I don't know why, but I never did use the AI much. I rely on the TC,
: >altimiter, DG, and airspeed to give me my picture, and leave the AI sort
: >of in the background. As a result, when the AI is covered, I fly
: >equally well. One CFI commented that I fly better on partial panel then
: >on the full panel.

: I have much the same experience. My instrument instructor was a nut
: for partial panel practice, so I got really good at it. I miss the DG
: when it's covered up, but for the most part, I fly the TC for bank and
: the ASI for pitch.

: After all these years, I honestly can't tell you how many bars up it
: takes to get Vy or what bank angle it takes for a standard rate turn.

Whew... I thought I was the only one! In straight/level, I rarely look at the
AI except once in awhile to cross-check. For straight/level it's useless, just as the
T&B/TC is for bank. It's really only good for setting up an attitude (whether it be
intentional transition or an "Oh crap... I busted my altitute/heading!")

-Cory

--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[Dave Butler]

Jose wrote:
> I don't know why, but I never did use the AI much. I rely on the TC,
> altimiter, DG, and airspeed to give me my picture, and leave the AI sort
> of in the background.

When I mostly flew an Archer, I did the same. Somehow in the transition to the
Mooney, I've becomre more fixated on the AI. Not sure why. I think my scan now
looks like that classic diagram in the training manuals where you look at the
AI, then some other instrument, then back to the AI, then some other instrument,
etc.

I've wondered whether the change is a function of performance / stability of the
airplane. The Archer was so stable it was easy to follow along just using the
result-based instruments. In the Mooney, it became necesary to be more aware of
slight changes in attitude that would affect the performance instruments in a
few seconds.

It also could be a better-quality AI in the Mooney that's easier to read.

The Mooney is the highest-performing airplane I've flown, but I've noticed that
people that fly jets seem to talk / write more about the importance of the AI.

....but I think you are experienced in higher-performance airplanes, right, Jose?

Dave

[Michael]

> When I mostly flew an Archer, I did the same. Somehow in the transition to the
> Mooney, I've becomre more fixated on the AI. Not sure why.

Because the Mooney demands more precision in your attitude control.
The cleaner the airplane, the more true that is. Once you reach the
ultimate clean airplane (a transport jet), there is no way to fly
partial panel. No jet crew that lost all attitude indicators in IMC
has ever survived. That's why the airlines have given up on teaching
partial panel. On the other hand, an old, slow, draggy ragwing can be
flown with no gyros at all, using just airspeed (or sound) for pitch
and compass for roll. I know someone who has over an hour of IMC time
in a ragwing with no gyros at all, doing it exactly that way. I've
done it at night under the hood in the TriPacer.

> The Archer was so stable it was easy to follow along just using the
> result-based instruments. In the Mooney, it became necesary to be more aware of
> slight changes in attitude that would affect the performance instruments in a
> few seconds.

Exactly correct.

This is why I teach the control-performance model of the scan - my
students are generally either flying slippery airplanes or are planning
to move up to them. For someone who will fly his entire career in an
Archer or Skyhawk, the FAA primary-secondary model works fine, and then
the AI is just a way to crosscheck.

Michael

[Jose]

> ...but I think you are experienced in higher-performance airplanes, right, Jose?

I've flown in transport category jets, but in the back seat. Way back. :)

I do have a little experience in high performance singles, but not very
much. And you are probably right about the AI being more critical in
high performance aircraft. Things happen faster.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Andrew Gideon]

Michael wrote:

> First off, with dual AI's next to each other, I believe that following
> a dying AI into an unusual attitude becomes far less likely, and thus
> while the chances of recovery from the unusual attitude are reduced
> slightly, the chances of encountering it in the first place are reduced
> dramatically.Â*Â*NotÂ*soÂ*withÂ*aÂ*backupÂ*vacuum *-Â*youÂ*haveÂ*toÂ*engageÂ*it.

This is the first of my two major reasons for preferring the backup AI. It
helps with problem detection. A backup vacuum doesn't.

> And even if you do, half the time (in my experience more) the problem
> is the AI, not the power source, so backup power for the AI does you no
> good.

And this is #2.

Some people to whom I've spoken about this have made a big deal about the
fact that the backup AI does nothing for a HI during a vacuum failure. My
response is typically "who cares?". Given a compass and a GPS, the HI has
plenty of backup already.

- Andrew

[Scott Moore]

wrote:
> : The reason why all electric panels are becoming common is because
> : electrical systems are more reliable than vacuum, and backup is easier to
> : provide for everything, a second battery. It also makes more sense to
> : unify around a single system, instead of having a hodge-podge of two
> : different systems.
>
> Easier is relative. Designing a truly redundant electrical system is
> nontrivial and expensive in both money, weight, and complexity. Strictly speaking,
> you should have dual alternators, dual busses with crossover breakers, etc, etc. It's
> not as simple as "throwing another battery" in the tail. If the system isn't designed
> properly or is improperly operated, a failed system can break the other system.
>
> The nice thing about the standard six-pack is that there's redundancy built
> into the instruments and sources. Yes, vacuum systems are less reliable, but short of
> something catastrophic, they are *completely* independent. It would probably be
> better to transition to an electric AI and vacuum TC as "standard equipment"... or
> maybe electric DG and vacuum TC. Still redundancy, but the likelihood of failure goes
> down with the electric replacements. A vac pump going out on a standard plane (and
> losing *all* bank except TC) is "unpleasant" and not that uncommon. Change 2 out of 3
> bank instruments to be electric, rather than vacuum and one failure isn't nearly so
> bad.
>
> -Cory
>

I agree with most of what you say, but this mystical belief by pilots that because
VAC is a "different" system than electrical it is more secure to have both.
Electrical systems can be made fully redundant, with separate generator, battery
and even distribution system and breakers. The fact that your airplane is not
comletely redundant may or may not degrade its reliability to LESS than the
inferior reliability of a vac pump.

For my own part, I'll be glad to see the vac components go. I'm tired of worrying
about the low replacement times on the vac pump, the posibility of contamination,
the lower general reliability of the components, etc.

[[email protected]]

Scott Moore > wrote:
: I agree with most of what you say, but this mystical belief by pilots that because
: VAC is a "different" system than electrical it is more secure to have both.
: Electrical systems can be made fully redundant, with separate generator, battery
: and even distribution system and breakers. The fact that your airplane is not
: comletely redundant may or may not degrade its reliability to LESS than the
: inferior reliability of a vac pump.

Even without full redundancy, single point failures must still be eliminated.

: For my own part, I'll be glad to see the vac components go. I'm tired of worrying
: about the low replacement times on the vac pump, the posibility of contamination,
: the lower general reliability of the components, etc.

I've done a number of systems designs where critical components, failure
modes, and redudancy were of major concern, so I am familiar with what goes into such
a system. I'm not saying that a fully redundant electrical system can be done... it
certainly can. My point is that for your average single-engine spam-can, fully
redundant electrical systems are generally overkill. Both financially and from
additional weight, a single-engine plane is not the right platform for a fully
redundant electrical system.

A vacuum pump, regulator, and a few feet of tubing provide relatively
inexpensive, completely redundant attitude information. Yes it's much less sexy and
less reliable than a fully redundant electrical system, but it's *MUCH* simpler,
cheaper, and lighter.

-Cory

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[Viperdoc]

I have an electric DG and AI in my Extra 300, which can be installed in a
removable panel for cross country flying. Neither has tumbled with gentle
acro (rolls, loops, spins), although it's probably hard on the bearings.

I suspect it would take more than an unusual attitude to tumble the gyros.

[Luke Scharf]

wrote:
> A vacuum pump, regulator, and a few feet of tubing provide relatively
> inexpensive, completely redundant attitude information. Yes it's much less sexy and
> less reliable than a fully redundant electrical system, but it's *MUCH* simpler,
> cheaper, and lighter.

Not only that, but it's already installed in most aircraft and doesn't
require a new Act Of Bereaucracy to make it legal.

-Luke

[Ron Natalie]

Dave Butler wrote:
>
> Did I miss any categories?
>
Redundant engine driven vacuum pumps.
Quite common on twins and some of the bigger singles. The rub on
singles is having a place to mount the second one.

[Ron Natalie]

Jose wrote:
>> I think that if you really feel the need for redundancy, the sensible
>> solution is replacing the T&B with an electric AI.
>
>
> I would not remove the T&B. If you add another AI, put it in a nearby
> hole, but not the T&B. No other instrument provides turn rate information.
>
> Jose
If I remove the T&B the autopilot won't work!

[Andrew Gideon]

Ron Natalie wrote:

> Redundant engine driven vacuum pumps.
> Quite common on twins and some of the bigger singles. The rub on
> singles is having a place to mount the second one.

Newer 172s (172R, 172S) even have dual vacuum pumps. That doesn't help
retrofitting, though.

- Andrew

[[email protected]]

Ron Natalie > wrote:
: Redundant engine driven vacuum pumps.
: Quite common on twins and some of the bigger singles. The rub on
: singles is having a place to mount the second one.

Now, even *I* say that's silly for a single. For a twin, sure... since it's likely already in place.
There's still a single point of failure (instrument itself)... An electric AI is more effective. Too bad they're
extra-ridiculously aviation priced.

-Cory
--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

[Scott Moore]

wrote:
> Scott Moore > wrote:
> : I agree with most of what you say, but this mystical belief by pilots that because
> : VAC is a "different" system than electrical it is more secure to have both.
> : Electrical systems can be made fully redundant, with separate generator, battery
> : and even distribution system and breakers. The fact that your airplane is not
> : comletely redundant may or may not degrade its reliability to LESS than the
> : inferior reliability of a vac pump.
>
> Even without full redundancy, single point failures must still be eliminated.
>
> : For my own part, I'll be glad to see the vac components go. I'm tired of worrying
> : about the low replacement times on the vac pump, the posibility of contamination,
> : the lower general reliability of the components, etc.
>
> I've done a number of systems designs where critical components, failure
> modes, and redudancy were of major concern, so I am familiar with what goes into such
> a system. I'm not saying that a fully redundant electrical system can be done... it
> certainly can. My point is that for your average single-engine spam-can, fully
> redundant electrical systems are generally overkill. Both financially and from
> additional weight, a single-engine plane is not the right platform for a fully
> redundant electrical system.
>
> A vacuum pump, regulator, and a few feet of tubing provide relatively
> inexpensive, completely redundant attitude information. Yes it's much less sexy and
> less reliable than a fully redundant electrical system, but it's *MUCH* simpler,
> cheaper, and lighter.
>
> -Cory

I disagree. A battery backed up electric AI is not cheap, but compared to all of the
components in a full vac system, it is, and its far more reliable. Even HAVING a
current VAC system does not eliminate that cost, since the MTBF for a vac pump is
down below 1000 hours, meaning you are going to have to change it soon in any case.

[Newps]

> Jose wrote:

No other instrument provides turn rate
>> information.

Why is rate of turn important compared to having another AI?

[Jose]

> Why is rate of turn important compared to having another AI?

Because then you know how fast you're turning, which is new information.
Another AI only tells you the same thing you already know from the
first AI.

If you are asking which partial panel technique I prefer, I have found
that in the airplanes I fly (which are not very high performance), I am
more precise focusing on the TC than on the AI anyway. I'll defer to
those in high performance aircraft that in that case it's different, but
in an emergency, dropping the flaps and extending the gear should turn a
slippery high performance aircraft into a more stable platform to get
down in.

Jose
--
Quantum Mechanics is like this: God =does= play dice with the universe,
except there's no God, and there's no dice. And maybe there's no universe.
for Email, make the obvious change in the address.

[Roger]

On Mon, 22 Aug 2005 18:06:14 -0700, Scott Moore
> wrote:
<snip>
>I disagree. A battery backed up electric AI is not cheap, but compared to all of the
>components in a full vac system, it is, and its far more reliable. Even HAVING a
>current VAC system does not eliminate that cost, since the MTBF for a vac pump is
>down below 1000 hours, meaning you are going to have to change it soon in any case.

Mine has a couple thousand on it and is still going strong.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

[[email protected]]

Andrew Gideon wrote:
> Michael wrote:
>
> > First off, with dual AI's next to each other, I believe that following
> > a dying AI into an unusual attitude becomes far less likely, and thus
> > while the chances of recovery from the unusual attitude are reduced
> > slightly, the chances of encountering it in the first place are reduced
> > dramatically. Not so with a backup vacuum - you have to engage it.
>
> This is the first of my two major reasons for preferring the backup AI. It
> helps with problem detection. A backup vacuum doesn't.

Which is why the Precise Flight standby systems include a low-vacuum
annunciator light.

-cwk.

[[email protected]]

Roger wrote:
> On Mon, 22 Aug 2005 18:06:14 -0700, Scott Moore
> > wrote:
> <snip>
> >I disagree. A battery backed up electric AI is not cheap, but compared to all of the
> >components in a full vac system, it is, and its far more reliable. Even HAVING a
> >current VAC system does not eliminate that cost, since the MTBF for a vac pump is
> >down below 1000 hours, meaning you are going to have to change it soon in any case.
>
> Mine has a couple thousand on it and is still going strong.

Do you have a wet pump? I would not fly hard IFR with a dry pump with
much over 500 hours, and I do have a standby vac. The "M" in MTBF means
half of the pumps last longer than that time, but it also means half
lasted less. If the ceilings are < 1000' I'm not rolling those dice.

-cwk.

[[email protected]]

Michael wrote:
> What kind of airplanes do you have? I can understand wanting attitude
> indication redundancy in a Bonanza, but it's overkill on a Skyhawk.

I'm of the general opinion that it's fairly difficult to go overboard
on safety equipment, though the C-150 with TCAS that I saw a year back
tripped even my meter.

> I think that if you really feel the need for redundancy, the sensible
> solution is replacing the T&B with an electric AI.

I'd agree with this. I have a 172 with the Precise Flight system that
was installed before I bought it and I certainly like having it. But
it's not really a cheap install and there is a recurring AD (unless
this is eliminated on new units?) so when you add it all in I doubt
it's much cheaper than the electric AI.

-cwk.

[Dave Butler]

Peter wrote:

> Didn't PF go bust recently, or was it some dual-vac pump company?

You're probably thinking of Aero-Advantage, which marketed a dual-rotor vacuum
pump. It was recently the subject of an AD requiring removal of installed pumps.
I have one, it will be removed at the next annual in October. Too bad. I think
it was a nice unit, but Aero-Advantage didn't have deep enough pockets to
maintain the certification in the face of reports of short service life in some
installations, IIRC.

Dave

[Andrew Gideon]

Peter wrote:

> Didn't PF go bust recently, or was it some dual-vac pump company?

I did notice this a while ago:

http://www.preciseflight.com/standby.html

I don't know the backstory, however.

- Andrew

[Mitty]

Almost for sure they have transferred the product (and the liability) into a
separate corporation with few or no tangible assets. Probably going naked on
liability insurance as well. This keeps the bloodsuckers from the Trial Lawyers
Association away.

Even good, decent people are forced to this kind of thing these days.

On 8/29/2005 12:30 PM, Andrew Gideon wrote the following:
> Peter wrote:
>
>
>>Didn't PF go bust recently, or was it some dual-vac pump company?
>
>
> I did notice this a while ago:
>
> http://www.preciseflight.com/standby.html
>
> I don't know the backstory, however.
>
> - Andrew
>

[[email protected]]

Do you have any evidence for this, or is it just your uninformed,
nonthinking prejudiced knee-jerk reaction?

[Mitty]

ROFL

On 8/29/2005 9:54 PM, wrote the following:
> Do you have any evidence for this, or is it just your uninformed,
> nonthinking prejudiced knee-jerk reaction?
>

[[email protected]]

Real intelligent. I guess I have my answer.

[Mitty]

On 8/30/2005 8:55 PM, wrote the following:
> Real intelligent. I guess I have my answer.
>

Actually, I was laughing because the only explanations I could come up with for
your cheap shot were either that (a) you have recently arrived here from another
planet or (b) that you are one of the bloodsuckers yourself. But I guess (c)
ignorance is always an option on the news groups.

But to answer your question more directly, in addition to many years experience
as a manager and business owner that has led me to understand these things,
consider the fact that the two companies have addresses 5.5 miles apart:

63354 Powell Butte Road Bend, OR 97701
1947 NE Curtis Bend, OR 97701

and

from the Precise Flight press release:

"... This new agreement will create an offsite facility for manufacturing,
customer service, order fulfillment and all marketing procedures..."

The keyword being, of course, "offsite." No one is saying "independently owned."

also The Vacuum Source's president was "a key member of the Precise Flight
sales team for the past 4 years"

and from The Vacuum Source:

"The company [The Vacuum Source] was established to offer products and
educational items dealing with primary vacuum source failures ... "

and

both companies TRACERT to the same ISP:

OrgName: OLM,LLC
OrgID: OLM
Address: 1980 University Lane
City: Lisle
StateProv: IL
PostalCode: 60532
Country: US

Kind of a coincidence that two totally independent companies in Bend, OR would
select the same hosting service in a couple thousand miles away in Illinois,
don't you think?

If you are really curious, you can go here:

http://egov.sos.state.or.us/br/pkg_web_name_srch_inq.show_detl?p_be_rsn=1107628&p_srce=BR_INQ&p_print=FALSE

and order copies of the articles of incorporation. Then compare the names for
matches to:

http://egov.sos.state.or.us/br/pkg_web_name_srch_inq.show_detl?p_be_rsn=699366&p_srce=BR_INQ&p_print=FALSE

That should be pretty definitive on whether they are a purpose-created shell or
not. My guess, as stated, is that they are. And for a good, logical reason:
Protection from the bloodsuckers.

[[email protected]]

Yes, I am a lawyer. As such, I am attuned to looking for logical proof
of an assertion. You have provided none. Being a manager and business
owner for "many" years qualifies for nothing other than something to do
with the specific area of your business. Your professed knowledge of
"these things", whatever "they" are, is so vague and general as to
render your opinion even more suspect. Moreover, your logic, if it can
be so charitibly characterised, is utterly backwards. If there were a
motive to insulate themselves from responsibility (i.e., liability) for
a defective product they would have been independently owned and not
have the nexus to the other company. The issue, however, is not that,
anyway; what and where are there ANY, ANY facts to support your rather
tired accusation that the actions were a reaction to so-called
bloodsuckers (and unsupported) allegations of overeaching by the
American justice system? If you truly knew anything about business,
you would know that these type of dual company setups are done
routinely for, primarily, tax and financial reasons way beyond the
scope of this newsgroup's interest area (which I entirely understand
and agree with), and too numerous to discuss, especially with people
who are more interested in generalities than cogency.

[Maule Driver]

ROFL

wrote:
> Yes, I am a lawyer. As such, I am attuned to looking for logical proof
> of an assertion. You have provided none. Being a manager and business
> owner for "many" years qualifies for nothing other than something to do
> with the specific area of your business. Your professed knowledge of
> "these things", whatever "they" are, is so vague and general as to
> render your opinion even more suspect. Moreover, your logic, if it can
> be so charitibly characterised, is utterly backwards. If there were a
> motive to insulate themselves from responsibility (i.e., liability) for
> a defective product they would have been independently owned and not
> have the nexus to the other company. The issue, however, is not that,
> anyway; what and where are there ANY, ANY facts to support your rather
> tired accusation that the actions were a reaction to so-called
> bloodsuckers (and unsupported) allegations of overeaching by the
> American justice system? If you truly knew anything about business,
> you would know that these type of dual company setups are done
> routinely for, primarily, tax and financial reasons way beyond the
> scope of this newsgroup's interest area (which I entirely understand
> and agree with), and too numerous to discuss, especially with people
> who are more interested in generalities than cogency.
>

[[email protected]]

Thank you for conceding the merits.

[Michael]

> Which is why the Precise Flight standby systems include a low-vacuum
> annunciator light.

Which merely gives you a false sense of confidence as the vacuum stays
on and the AI fails.

Since AI's fail as often as dry pumps (and far more often than wet
pumps) the low-vacuum annunciator light really doesn't help much.

The real solution would be a tiny magnet integrated into the vacuum
gyro and a tiny coil fixed in place. This would act as a generator,
and would likely make enough juice to keep an LED lit. LED goes out -
problem. Doesn't matter whether it's a failed AI or failed vacuum.

Now good luck getting that certified for GA at any sort of reasonable
price.

Michael

[Andrew Gideon]

Michael wrote:

> Now good luck getting that certified for GA at any sort of reasonable
> price.

In looking at some AIs and TCs, I did note at least one product where the
flag is based not upon power but upon the rate of spin of the gyro.

This was the Mid Continental 1394T100-7A according to my notes.

- Andrew

[Mitty]

Wound a little tight, are we? Remember in high school how they told you to
break your writings into paragraphs to improve readability? Oh, and in law
school when they told you about sticking to the facts? I made no accusations.
I simply said it was likely. And I continue to believe that.

Your response is like us standing together in the rain and you asking me to
PROVE that it is raining. As I said, ROFL.

But -- please post again. Tell us how all the PI lawyers are really members of
the Mother Teresa Society and are unwittingly getting rich out of selfless love
for humanity. Challenge me to prove that it is not so. This is getting to be
hilarious.

On 8/31/2005 9:36 PM, wrote the following:
> Yes, I am a lawyer. As such, I am attuned to looking for logical proof
> of an assertion. You have provided none. Being a manager and business
> owner for "many" years qualifies for nothing other than something to do
> with the specific area of your business. Your professed knowledge of
> "these things", whatever "they" are, is so vague and general as to
> render your opinion even more suspect. Moreover, your logic, if it can
> be so charitibly characterised, is utterly backwards. If there were a
> motive to insulate themselves from responsibility (i.e., liability) for
> a defective product they would have been independently owned and not
> have the nexus to the other company. The issue, however, is not that,
> anyway; what and where are there ANY, ANY facts to support your rather
> tired accusation that the actions were a reaction to so-called
> bloodsuckers (and unsupported) allegations of overeaching by the
> American justice system? If you truly knew anything about business,
> you would know that these type of dual company setups are done
> routinely for, primarily, tax and financial reasons way beyond the
> scope of this newsgroup's interest area (which I entirely understand
> and agree with), and too numerous to discuss, especially with people
> who are more interested in generalities than cogency.
>