C182 Glass Panel

[Scott Schluer]

I've got a question about the glass panel displays in the C182 (or any other
aircraft for that matter). I was reading this month's edition of AOPA Pilot
magazine and the cover story is the C182T and the new glass panel displays
Cessna decided to incorporate and it got me thinking. My question is: how
does a glass panel display take information received from the pitot-static
and gyro systems and translate that into the display? On "standard" panels,
the pitot-static and gyro systems power the instruments be means of a
mechanical linkage between air pressure differentials or gyros and the
instrument display itself. Now, on a glass panel, I'm assuming that
mechanical linkage is no more. Is everything I know about how instruments
work out the window with glass panels?

For example, if my static source becomes clogged, I would assume that the
pitot-staitc instruments on the glass panel would be affected the same as
they always were. But can I still break the glass on one of the other
"standard" instruments using static pressure that the 182T still
incorporates for redundancy (airspeed, altimiter)? If I broke the glass on
the standard altimiter for example (assuming my glass panel was fully
functional so that I wouldn't need to rely on the standard altimiter, but
the static source was blocked causing erroneous indications), would that
allow static air pressure to flow where it needs to in order to accurately
reflect on the glass panel display also?

I'm just a little confused as to how the glass panel instruments actually
work. Can someone provide an explanation?

Thanks,

Scott

[C J Campbell]

The glass panel instruments still use the pitot/static system. If your
static port becomes plugged, pull the alternate static source knob. Don't go
breaking any glass instruments.

The glass panel does not use gyros, but the backup instruments do. The
Garmin 1000 gets pitch information by detecting changes in the vertical
component of the Earth's magnetic field and by cross referencing that with
information from the GPS. It does the same with roll information. It sounds
complicated, but it really is just a fancy compass.

If it were not for legacy aircraft in the ATC system we could dump the
excessively complicated dependence on magnetic headings and give all
vectors, winds, headings, etc., relative to true north. Continually mapping
the shifting magnetic field and updating databases, IFR and VFR charts,
radio navigation aids, and training materials is a major expense.

[Earl]

> I've got a question about the glass panel displays in the C182 (or any
other
> aircraft for that matter). I was reading this month's edition of AOPA
Pilot
> magazine and the cover story is the C182T and the new glass panel displays
> Cessna decided to incorporate and it got me thinking. My question is: how
> does a glass panel display take information received from the pitot-static
> and gyro systems and translate that into the display? On "standard"
panels,
> the pitot-static and gyro systems power the instruments be means of a
> mechanical linkage between air pressure differentials or gyros and the
> instrument display itself. Now, on a glass panel, I'm assuming that
> mechanical linkage is no more. Is everything I know about how instruments
> work out the window with glass panels?

There's a pressure transducer somewhere for the glass panels that convert
the air pressure into an electrical signal that the computer can understand.
The computer then draws the instrument on the display. There are separate
sensors for pitot and static.

>
> For example, if my static source becomes clogged, I would assume that the
> pitot-staitc instruments on the glass panel would be affected the same as
> they always were. But can I still break the glass on one of the other
> "standard" instruments using static pressure that the 182T still
> incorporates for redundancy (airspeed, altimiter)? If I broke the glass on
> the standard altimiter for example (assuming my glass panel was fully
> functional so that I wouldn't need to rely on the standard altimiter, but
> the static source was blocked causing erroneous indications), would that
> allow static air pressure to flow where it needs to in order to accurately
> reflect on the glass panel display also?

Depends on where the clog is. If all the instruments in the cockpit that
depend on static pressure are plumbed to a single static port on the
airplane body, and that static port clogs with ice, then all the instruments
including the computer are affected. You might able to use alternate static
source to get around it. Know your aircraft systems..... the glass displays
may or may not share the pitot static system plumbing with the old gauges.

>
> I'm just a little confused as to how the glass panel instruments actually
> work. Can someone provide an explanation?
>
> Thanks,
>
> Scott
>
>

[Cub Driver]

>The
>Garmin 1000 gets pitch information by detecting changes in the vertical
>component of the Earth's magnetic field and by cross referencing that with
>information from the GPS. It does the same with roll information. It sounds
>complicated, but it really is just a fancy compass.

It sounds like an upgrade of the Garmin 196!

all the best -- Dan Ford
email: (requires authentication)

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[Ben Jackson]

In article >,
C J Campbell > wrote:
>
>The glass panel does not use gyros, but the backup instruments do. The
>Garmin 1000 gets pitch information by detecting changes in the vertical
>component of the Earth's magnetic field and by cross referencing that with
>information from the GPS.

Those sources aren't responsive enough. I believe the uses MEMS gyros
to provide instantaneous relative attitude information and combine them
in a Kalman filter with the other sources you mention to get long term
absolute attitude reference.

--
Ben Jackson
>
http://www.ben.com/

[Marc J. Zeitlin]

Cub Driver wrote:

Unnamed Quoted person:
> >The
> >Garmin 1000 gets pitch information by detecting changes in the vertical
> >component of the Earth's magnetic field and by cross referencing that
with
> >information from the GPS. It does the same with roll information. It
sounds
> >complicated, but it really is just a fancy compass.
>
> It sounds like an upgrade of the Garmin 196!

Except that the quoted paragraph is incorrect. While the 1000 does use the
GPS and a magnetometer to stabilize the AHRS and to allow for "flying
reboots", it does use a standard AHRS (solid state gyros) for attitude
reference. From the Garmin documentation:

"Advanced AHRS architecture
For reliable output and referencing of aircraft position, rate, vector and
acceleration data, the G1000 uses Garmin's innovative GRS77 Attitude and
Heading Reference System (AHRS). Able to properly reference itself even
while the aircraft is moving, the Garmin AHRS offers all the standard
elements of traditional strap-down AHRS - at a fraction of the cost. What's
more, it uses additional comparative inputs from GPS, magnetometer and air
data computer information to achieve new levels of integrity, reliability
and precision."

Notice the "additional comparative inputs".

--
Marc J. Zeitlin email: |
http://www.cozybuilders.org/
http://marc.zeitlin.home.comcast.net/

[Newps]

Have you ever tried to break the glass on one of them instruments? It's
pretty damn hard to do and impossible if you don't have a good sized
hammer. In my 182 I know exactly where the static lines are under the
panel. In the event both static ports get blocked I will reach for the
static line near my left shin and pull it off the fitting. This is
infinitely easier than busting a pretty small piece of glass and won't
end up costing me any money.

Scott Schluer wrote:

> I've got a question about the glass panel displays in the C182 (or any other
> aircraft for that matter). I was reading this month's edition of AOPA Pilot
> magazine and the cover story is the C182T and the new glass panel displays
> Cessna decided to incorporate and it got me thinking. My question is: how
> does a glass panel display take information received from the pitot-static
> and gyro systems and translate that into the display? On "standard" panels,
> the pitot-static and gyro systems power the instruments be means of a
> mechanical linkage between air pressure differentials or gyros and the
> instrument display itself. Now, on a glass panel, I'm assuming that
> mechanical linkage is no more. Is everything I know about how instruments
> work out the window with glass panels?
>
> For example, if my static source becomes clogged, I would assume that the
> pitot-staitc instruments on the glass panel would be affected the same as
> they always were. But can I still break the glass on one of the other
> "standard" instruments using static pressure that the 182T still
> incorporates for redundancy (airspeed, altimiter)? If I broke the glass on
> the standard altimiter for example (assuming my glass panel was fully
> functional so that I wouldn't need to rely on the standard altimiter, but
> the static source was blocked causing erroneous indications), would that
> allow static air pressure to flow where it needs to in order to accurately
> reflect on the glass panel display also?
>
> I'm just a little confused as to how the glass panel instruments actually
> work. Can someone provide an explanation?
>
> Thanks,
>
> Scott
>
>

[Scott Schluer]

Makes sense...also an obvious point about the alternate static air. ;-) I
don't have much experience in newer aircraft, most of my flight time has
been logged in older C172s with no alternate static port.

"C J Campbell" > wrote in message
...
> The glass panel instruments still use the pitot/static system. If your
> static port becomes plugged, pull the alternate static source knob. Don't
go
> breaking any glass instruments.
>
> The glass panel does not use gyros, but the backup instruments do. The
> Garmin 1000 gets pitch information by detecting changes in the vertical
> component of the Earth's magnetic field and by cross referencing that with
> information from the GPS. It does the same with roll information. It
sounds
> complicated, but it really is just a fancy compass.
>
> If it were not for legacy aircraft in the ATC system we could dump the
> excessively complicated dependence on magnetic headings and give all
> vectors, winds, headings, etc., relative to true north. Continually
mapping
> the shifting magnetic field and updating databases, IFR and VFR charts,
> radio navigation aids, and training materials is a major expense.
>
>

[Mark]

"Scott Schluer" > wrote in message news:<NQ2%b.2402$id3.646@fed1read01>...
> I've got a question about the glass panel displays in the C182 (or any other
> aircraft for that matter). I was reading this month's edition of AOPA Pilot
> magazine and the cover story is the C182T and the new glass panel displays
> Cessna decided to incorporate and it got me thinking. My question is: how
> does a glass panel display take information received from the pitot-static
> and gyro systems and translate that into the display? On "standard" panels,
> the pitot-static and gyro systems power the instruments be means of a
> mechanical linkage between air pressure differentials or gyros and the
> instrument display itself. Now, on a glass panel, I'm assuming that
> mechanical linkage is no more. Is everything I know about how instruments
> work out the window with glass panels?
>
> For example, if my static source becomes clogged, I would assume that the
> pitot-staitc instruments on the glass panel would be affected the same as
> they always were. But can I still break the glass on one of the other
> "standard" instruments using static pressure that the 182T still
> incorporates for redundancy (airspeed, altimiter)? If I broke the glass on
> the standard altimiter for example (assuming my glass panel was fully
> functional so that I wouldn't need to rely on the standard altimiter, but
> the static source was blocked causing erroneous indications), would that
> allow static air pressure to flow where it needs to in order to accurately
> reflect on the glass panel display also?
>
> I'm just a little confused as to how the glass panel instruments actually
> work. Can someone provide an explanation?
>
> Thanks,
>
> Scott

Side note... (sorry for the thread jacking).

Has anyone got the endorsement needed to fly a glass panel display
182? I think it's call a "Advance Technology Endorsement"? I'm
wondering what the checkout is like.

[john smith]

Mark wrote:
> "Scott Schluer" > wrote in message news:<NQ2%b.2402$id3.646@fed1read01>...
>
>>I've got a question about the glass panel displays in the C182 (or any other
>>aircraft for that matter). I was reading this month's edition of AOPA Pilot
>>magazine and the cover story is the C182T and the new glass panel displays
>>Cessna decided to incorporate and it got me thinking. My question is: how
>>does a glass panel display take information received from the pitot-static
>>and gyro systems and translate that into the display? On "standard" panels,
>>the pitot-static and gyro systems power the instruments be means of a
>>mechanical linkage between air pressure differentials or gyros and the
>>instrument display itself. Now, on a glass panel, I'm assuming that
>>mechanical linkage is no more. Is everything I know about how instruments
>>work out the window with glass panels?
>>
>>For example, if my static source becomes clogged, I would assume that the
>>pitot-staitc instruments on the glass panel would be affected the same as
>>they always were. But can I still break the glass on one of the other
>>"standard" instruments using static pressure that the 182T still
>>incorporates for redundancy (airspeed, altimiter)? If I broke the glass on
>>the standard altimiter for example (assuming my glass panel was fully
>>functional so that I wouldn't need to rely on the standard altimiter, but
>>the static source was blocked causing erroneous indications), would that
>>allow static air pressure to flow where it needs to in order to accurately
>>reflect on the glass panel display also?
>>
>>I'm just a little confused as to how the glass panel instruments actually
>>work. Can someone provide an explanation?
>>
>>Thanks,
>>
>>Scott
>
>
> Side note... (sorry for the thread jacking).
>
> Has anyone got the endorsement needed to fly a glass panel display
> 182? I think it's call a "Advance Technology Endorsement"? I'm
> wondering what the checkout is like.

You mean FITS?

[C J Campbell]

"Mark" > wrote in message >
> Side note... (sorry for the thread jacking).
>
> Has anyone got the endorsement needed to fly a glass panel display
> 182? I think it's call a "Advance Technology Endorsement"? I'm
> wondering what the checkout is like.

As I understand it, there is not a specific endorsement for this. You still
should get training from someone experienced in using the equipment, though.

[C J Campbell]

"Scott Schluer" > wrote in message
news:NQ2%b.2402$id3.646@fed1read01...
> I've got a question about the glass panel displays in the C182 (or any
other
> aircraft for that matter).

The Garmin G1000 is far more advanced technologically than the Avidynes and
other glass panels found in aircraft like the Cirrus. It actually allows
Cessna to claim technological leadership over these 'newer' designs.

The G1000 is fully integrated -- no separate radio or GPS stack like in the
Cirrus. It is also much higher (XGA) resolution and offers terrain shading.
The Avidyne only has VGA resolution and contour coloring. It is WAAS
capable, which the Cirrus avionics are not. There are numerous user
interface advantages to the Garmin, too.

Unfortunately, G1000 will be available only to OEMs for three to four years,
and then available as an upgrade to only a very small number of aircraft.
Garmin claims that the huge holes that need to be cut in the panel for the
G1000 can weaken some aircraft structurally and they don't want to bother
figuring out an upgrade path when they can sell all the units they can
manufacture now.

Personally, I think the better upgrade route would be the CNX-80 GPS/NAV/COM
with the MX-20 MFD. You can get an Avidyne PFD if you want that. Sure, it is
not quite the same as a G1000, but it is available now.

[Bill Denton]

Just in case you're interested, Mooney is offering the G1000 in the Ovation
and Bravo. They're calling them the "GX" series. And you can read all about
it at www.mooney.com.

"C J Campbell" > wrote in message
...
>
> "Scott Schluer" > wrote in message
> news:NQ2%b.2402$id3.646@fed1read01...
> > I've got a question about the glass panel displays in the C182 (or any
> other
> > aircraft for that matter).
>
> The Garmin G1000 is far more advanced technologically than the Avidynes
and
> other glass panels found in aircraft like the Cirrus. It actually allows
> Cessna to claim technological leadership over these 'newer' designs.
>
> The G1000 is fully integrated -- no separate radio or GPS stack like in
the
> Cirrus. It is also much higher (XGA) resolution and offers terrain
shading.
> The Avidyne only has VGA resolution and contour coloring. It is WAAS
> capable, which the Cirrus avionics are not. There are numerous user
> interface advantages to the Garmin, too.
>
> Unfortunately, G1000 will be available only to OEMs for three to four
years,
> and then available as an upgrade to only a very small number of aircraft.
> Garmin claims that the huge holes that need to be cut in the panel for the
> G1000 can weaken some aircraft structurally and they don't want to bother
> figuring out an upgrade path when they can sell all the units they can
> manufacture now.
>
> Personally, I think the better upgrade route would be the CNX-80
GPS/NAV/COM
> with the MX-20 MFD. You can get an Avidyne PFD if you want that. Sure, it
is
> not quite the same as a G1000, but it is available now.
>
>

[C J Campbell]

"Bill Denton" > wrote in message
...
> Just in case you're interested, Mooney is offering the G1000 in the
Ovation
> and Bravo. They're calling them the "GX" series. And you can read all
about
> it at www.mooney.com.
>

Diamond, too. Yeah. Cirrus and Lancair actually have some catching up to do.
Good. Maybe technological progress in aviation is possible after all. Even
better, maybe competition will return to the light plane market.

Now, if we could just talk Cessna into actually building some of these
wonder aircraft....

The dealers said that they had orders enough to build 250 more planes than
planned this year. Cessna grudgingly allowed 59 more. Still less than what
they sold last year. And then complained that sales are down for this year.
Idiots.

[Dennis O'Connor]

uh huh, all your eggs in one basket....

I like gee-whiz gadgets as well as the next guy, but: Make sure you have a
couple of steam gauges, and a dinosauer radio with a vor/gs needle for when
all the magic smoke departs the glass panel...
denny


> The Garmin G1000 is far more advanced technologically than the Avidynes
and
> other glass panels found in aircraft like the Cirrus. It actually allows
> Cessna to claim technological leadership over these 'newer' designs.

[C J Campbell]

"Dennis O'Connor" > wrote in message
...
> uh huh, all your eggs in one basket....
>
> I like gee-whiz gadgets as well as the next guy, but: Make sure you have a
> couple of steam gauges, and a dinosauer radio with a vor/gs needle for
when
> all the magic smoke departs the glass panel...
> denny

Believe it or not, it is just as redundant as what you have now, probably
even more so. G1000 has a backup battery. Your current radios probably do
not. It has two separate panels, each with their own radio, GPS, and
navigation system. They run off separate electrical busses. The MFD
information can be displayed on the PFD.

Most small planes have only one GS. The G1000 gives you two. I think it is
extremely ignorant and unfair to characterize the system as "all your eggs
in one basket."

In the Cessna installation, you still have the steam gauges in a row across
the bottom of the panel, but it is not true in all other installations, nor
is it especially necessary.