CFII oral exam guide questions?

[Robert M. Gary]

Can anyone point me to an oral exam guide (internet preferred) for the
CFII? I see lots of stuff for IR but no one seems to publish anything
for the CFII specifically. Looking for specific questions on teaching
techniques.

-Robert

[[email protected]]

I outlined the CFII PTS, including listing and comments on common
errors at
http://greggordon.org/flying/flightInstructorInstrumentRating.htm
Greg

Robert M. Gary wrote:
> Can anyone point me to an oral exam guide (internet preferred) for the
> CFII? I see lots of stuff for IR but no one seems to publish anything
> for the CFII specifically. Looking for specific questions on teaching
> techniques.
>
> -Robert

[Robert M. Gary]

Awesome! Thanks. On my check ride I'm to prepare a presentation on
attitude instrument flying. I like some of the things you have in your
lesson plan that I'll probably incorporate into mine.
Thanks!

-Robert


wrote:
> I outlined the CFII PTS, including listing and comments on common
> errors at
> http://greggordon.org/flying/flightInstructorInstrumentRating.htm
> Greg
>
> Robert M. Gary wrote:
> > Can anyone point me to an oral exam guide (internet preferred) for the
> > CFII? I see lots of stuff for IR but no one seems to publish anything
> > for the CFII specifically. Looking for specific questions on teaching
> > techniques.
> >
> > -Robert

[Mitty]

You might look at:

http://www.dauntless-soft.com/PRODUCTS/RideReady/airplane.asp?DMODE=FAATEST

I have used their software for written tests and found it to be very
good. I tried the "RideReady" Commercial oral package when it was
very new, a couple of years ago and at that time I thought it was kind
of weak. YMMV, though, and you can at least look at the free trial
download. I would suggest you ask Adrian how many questions are in
the full package. IIRC the Commercial package I tried had a
relatively small number -- like under 50. That was my main criticism
of it.

On 6/9/2006 12:11 PM, Robert M. Gary wrote the following:
> Can anyone point me to an oral exam guide (internet preferred) for the
> CFII? I see lots of stuff for IR but no one seems to publish anything
> for the CFII specifically. Looking for specific questions on teaching
> techniques.
>
> -Robert
>

[Jim Macklin]

You can explain how a VOR/DME works with a simple visual
model.

There is a large lake with an island in the middle. There
is a lighthouse with a rotating beacon that makes one
revolution a minute. It has a white beacon and a green
beacon, when the white beacon is passing North, a big strobe
light on top flashes and a very loud horn sounds.

You see the strobe light flash and 6 seconds later see the
green beacon sweep by. Where are you? 216 degrees from the
beacon. Ten seconds after the strobe, you hear the horn,
how far away? 2 miles.

VOR is the same, just faster.


Steer your boat so the bow always points to the light and
you've got an ADF homer.



--
James H. Macklin
ATP,CFI,A&P

--
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
some support
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.


"Robert M. Gary" > wrote in message
oups.com...
|
| Mitty wrote:
| > You might look at:
| >
| >
http://www.dauntless-soft.com/PRODUCTS/RideReady/airplane.asp?DMODE=FAATEST
| >
| > I have used their software for written tests and found
it to be very
| > good. I tried the "RideReady" Commercial oral package
when it was
| > very new, a couple of years ago and at that time I
thought it was kind
| > of weak.
|
| They don't appear to have anything for the CFII :(. As it
turn out, my
| instructor knows an enourmous amount of stuff and I'm
spending late
| nights learning stuff I never thought I'd know.
| 1) He showed me disassembled instruments when describing
how each works
| (how well can most of us explain how an altimeter really
works inside,
| I thought a mag compass was ball shaped )
| 2) He also explained how VORs really work (I thought they
broadcast
| actual radials but they actually time the difference
between a
| reference signal and a rotating sweeping signal).
| 3) He expects me to memorize the freq of markers and be
able to
| distinguish a loc freq from vor freq by looking at the
freq number.
| 4) Even the stuff I thought I knew was wrong. I thought
lots of air was
| always running through the pitot tube and out the drain
hole.
| Apparently only a very, very small amount of air comes out
the back of
| the drain hole and the actual volume of air running
through the pitot
| is very small. Looking at all the books, I got the
impression air was
| just rushing through.
|
| -Robert
|

[Mark Hansen]

On 06/13/06 11:15, Jim Macklin wrote:
> You can explain how a VOR/DME works with a simple visual
> model.
>
> There is a large lake with an island in the middle. There
> is a lighthouse with a rotating beacon that makes one
> revolution a minute. It has a white beacon and a green
> beacon, when the white beacon is passing North, a big strobe
> light on top flashes and a very loud horn sounds.
>
> You see the strobe light flash and 6 seconds later see the
> green beacon sweep by. Where are you? 216 degrees from the
> beacon. Ten seconds after the strobe, you hear the horn,
> how far away? 2 miles.

So are both the white and green beacons rotating?

Don't you just need an omnidirectional strobe (with horn for
distance measurements) and a single rotating beacon?

>
> VOR is the same, just faster.
>
>
> Steer your boat so the bow always points to the light and
> you've got an ADF homer.
>
>
>



--
Mark Hansen, PP-ASEL, Instrument Airplane
Cal Aggie Flying Farmers
Sacramento, CA

[Jim Macklin]

Just like the rotating beacon at the airport, the two lights
are 180 apart and rotate on the common shaft.

Yes, you could have just one light rotating, but two
identifiable beacons makes the system more useable and
faster.

English lesson... "white beacon passing North...green beacon
sweeps by" Seems that both are moving.



"Mark Hansen" > wrote in message
...
| On 06/13/06 11:15, Jim Macklin wrote:
| > You can explain how a VOR/DME works with a simple visual
| > model.
| >
| > There is a large lake with an island in the middle.
There
| > is a lighthouse with a rotating beacon that makes one
| > revolution a minute. It has a white beacon and a green
| > beacon, when the white beacon is passing North, a big
strobe
| > light on top flashes and a very loud horn sounds.
| >
| > You see the strobe light flash and 6 seconds later see
the
| > green beacon sweep by. Where are you? 216 degrees from
the
| > beacon. Ten seconds after the strobe, you hear the
horn,
| > how far away? 2 miles.
|
| So are both the white and green beacons rotating?
|
| Don't you just need an omnidirectional strobe (with horn
for
| distance measurements) and a single rotating beacon?
|
| >
| > VOR is the same, just faster.
| >
| >
| > Steer your boat so the bow always points to the light
and
| > you've got an ADF homer.
| >
| >
| >
|
|
|
| --
| Mark Hansen, PP-ASEL, Instrument Airplane
| Cal Aggie Flying Farmers
| Sacramento, CA

[Mark Hansen]

On 06/13/06 12:08, Jim Macklin wrote:
> Just like the rotating beacon at the airport, the two lights
> are 180 apart and rotate on the common shaft.
>
> Yes, you could have just one light rotating, but two
> identifiable beacons makes the system more useable and
> faster.
>
> English lesson... "white beacon passing North...green beacon
> sweeps by" Seems that both are moving.

Thanks, but I don't really need the English lesson.
Your description made it sound like there were two rotating
beacons, and I couldn't see why that was necessary to make
the point. I asked the question so you could clarify.

Having one rotating beacon seems to illustrate the functionality.
If the point is to make the system easy for a student pilot to
understand, why not keep it simple?

The "useable[sic] and faster" issue isn't really necessary for
the student to understand how the system works, IMHO :-)

I do like the analogy, though.

Thanks,


>
>
>
> "Mark Hansen" > wrote in message
> ...
> | On 06/13/06 11:15, Jim Macklin wrote:
> | > You can explain how a VOR/DME works with a simple visual
> | > model.
> | >
> | > There is a large lake with an island in the middle.
> There
> | > is a lighthouse with a rotating beacon that makes one
> | > revolution a minute. It has a white beacon and a green
> | > beacon, when the white beacon is passing North, a big
> strobe
> | > light on top flashes and a very loud horn sounds.
> | >
> | > You see the strobe light flash and 6 seconds later see
> the
> | > green beacon sweep by. Where are you? 216 degrees from
> the
> | > beacon. Ten seconds after the strobe, you hear the
> horn,
> | > how far away? 2 miles.
> |
> | So are both the white and green beacons rotating?
> |
> | Don't you just need an omnidirectional strobe (with horn
> for
> | distance measurements) and a single rotating beacon?
> |
> | >
> | > VOR is the same, just faster.
> | >
> | >
> | > Steer your boat so the bow always points to the light
> and
> | > you've got an ADF homer.
> | >
> | >
> | >
> |
> |
> |
> | --
> | Mark Hansen, PP-ASEL, Instrument Airplane
> | Cal Aggie Flying Farmers
> | Sacramento, CA
>
>



--
Mark Hansen, PP-ASEL, Instrument Airplane
Cal Aggie Flying Farmers
Sacramento, CA

[Michael]

Robert M. Gary wrote:
> 1) He showed me disassembled instruments when describing how each works
> (how well can most of us explain how an altimeter really works inside,
> I thought a mag compass was ball shaped )

I always thought it was worthwhile to show an instrument student a
disassembled compass. Once he sees how the counterweight works to
compensate for the vertical component of the magnetic field, turning
errors are obvious - as well as why there are no turning errors while
taxiing. Accelerationa and deceleration errors are equally obvious.

> 2) He also explained how VORs really work (I thought they broadcast
> actual radials but they actually time the difference between a
> reference signal and a rotating sweeping signal).

You know, I once interviewed an electrical engineer who worked for a
major GA autopilot manufacturer who told me he worked on VOR. He
couldn't explain it to me. Of course I didn't hire him.

> 3) He expects me to memorize the freq of markers and be able to
> distinguish a loc freq from vor freq by looking at the freq number.

Well, it can be done - but WHY? There is some value in knowing that
the radio determines whether to use the VOR or LOC circuitry based on
the frequency selected. There is much value to understanding the
difference, especially as it applies to the validity of a VOR check for
LOC/ILS ops. Memorizing what the actual frequencies are seems rather
pointless.

> 4) Even the stuff I thought I knew was wrong. I thought lots of air was
> always running through the pitot tube and out the drain hole.
> Apparently only a very, very small amount of air comes out the back of
> the drain hole and the actual volume of air running through the pitot
> is very small. Looking at all the books, I got the impression air was
> just rushing through.

Then you really didn't understand the physics of how a pitot tube
works.

Think of a pitot tube as an energy conversion device. There is energy
in moving air. There is energy in pressurized air. A pitot tube is a
device for converting the former into the latter. An ASI is actually a
pressure gauge (usually a brass bellows that drives the needle) that
measures the difference between the ram pressure and the static
pressure. The ram pressure is always going to be higher, because the
speed of the airplane is forcing air in, and pressurizing it.

All the drain hole does is cause error (non-heated pitot tubes often
don't even have drain holes - the primary function of the drain hole is
to allow the water formed when the pitot heat melts the ice to drain)
by allowing some of the ram pressure to bleed off. If the pitot tube
is to give a reasonably accurate indication, the rate of leakage MUST
be small.

Amazing how much you can learn while working on a rating that
supposedly only allows you to teach what you already know.

Michael

[Mark Hansen]

On 06/13/06 12:34, Michael wrote:
> Robert M. Gary wrote:
>> 1) He showed me disassembled instruments when describing how each works
>> (how well can most of us explain how an altimeter really works inside,
>> I thought a mag compass was ball shaped )
>
> I always thought it was worthwhile to show an instrument student a
> disassembled compass. Once he sees how the counterweight works to
> compensate for the vertical component of the magnetic field, turning
> errors are obvious - as well as why there are no turning errors while
> taxiing. Accelerationa and deceleration errors are equally obvious.
>
>> 2) He also explained how VORs really work (I thought they broadcast
>> actual radials but they actually time the difference between a
>> reference signal and a rotating sweeping signal).
>
> You know, I once interviewed an electrical engineer who worked for a
> major GA autopilot manufacturer who told me he worked on VOR. He
> couldn't explain it to me. Of course I didn't hire him.
>
>> 3) He expects me to memorize the freq of markers and be able to
>> distinguish a loc freq from vor freq by looking at the freq number.
>
> Well, it can be done - but WHY? There is some value in knowing that
> the radio determines whether to use the VOR or LOC circuitry based on
> the frequency selected. There is much value to understanding the
> difference, especially as it applies to the validity of a VOR check for
> LOC/ILS ops. Memorizing what the actual frequencies are seems rather
> pointless.
>
>> 4) Even the stuff I thought I knew was wrong. I thought lots of air was
>> always running through the pitot tube and out the drain hole.
>> Apparently only a very, very small amount of air comes out the back of
>> the drain hole and the actual volume of air running through the pitot
>> is very small. Looking at all the books, I got the impression air was
>> just rushing through.
>
> Then you really didn't understand the physics of how a pitot tube
> works.
>
> Think of a pitot tube as an energy conversion device. There is energy
> in moving air. There is energy in pressurized air. A pitot tube is a
> device for converting the former into the latter. An ASI is actually a
> pressure gauge (usually a brass bellows that drives the needle) that
> measures the difference between the ram pressure and the static
> pressure. The ram pressure is always going to be higher, because the
> speed of the airplane is forcing air in, and pressurizing it.
>
> All the drain hole does is cause error (non-heated pitot tubes often
> don't even have drain holes - the primary function of the drain hole is
> to allow the water formed when the pitot heat melts the ice to drain)
> by allowing some of the ram pressure to bleed off. If the pitot tube
> is to give a reasonably accurate indication, the rate of leakage MUST
> be small.

I thought this allowed rain water to drain as well. Otherwise, couldn't
the water build up and eventually get into the pressure line to the
ASI?

Or does the air pressure keep/force the water out the front of the
tube somehow?

>
> Amazing how much you can learn while working on a rating that
> supposedly only allows you to teach what you already know.
>
> Michael
>



--
Mark Hansen, PP-ASEL, Instrument Airplane
Cal Aggie Flying Farmers
Sacramento, CA

[Robert M. Gary]

Michael wrote:
> Then you really didn't understand the physics of how a pitot tube
> works.
>
> Think of a pitot tube as an energy conversion device. There is energy
> in moving air. There is energy in pressurized air. A pitot tube is a
> device for converting the former into the latter. An ASI is actually a
> pressure gauge (usually a brass bellows that drives the needle) that
> measures the difference between the ram pressure and the static
> pressure. The ram pressure is always going to be higher, because the
> speed of the airplane is forcing air in, and pressurizing it.

I understood that. I just way over estimated how much air went through
the pitot tube. Any tube that has a hole in the front and a smaller
hole in the back would do the job. The net pressure to the A/S
indicator would be less but that's just a calibration issue. So I
understood the concept but over estimated the flow.

-Robert

[Roy Smith]

Michael > wrote:
>I always thought it was worthwhile to show an instrument student a
>disassembled compass. Once he sees how the counterweight works to
>compensate for the vertical component of the magnetic field, turning
>errors are obvious

Seeing stuff opened up is always useful. My FBO has a sectioned
carburator sitting around in one of the classrooms; I take every
opportunity to show people how it works inside. Some of them actually
pay attention :-)

I also like to pull the cowling off planes and show students what's
underneath. Many have never seen anything more than can be seen from
the oil filler door. It's very instructive when you see things like
the alternate air control opening up a little door on the air filter
housing, or tracing out the wires from the plugs to the magnetos.

>Well, it can be done - but WHY? There is some value in knowing that
>the radio determines whether to use the VOR or LOC circuitry based on
>the frequency selected. There is much value to understanding the
>difference, especially as it applies to the validity of a VOR check for
>LOC/ILS ops. Memorizing what the actual frequencies are seems rather
>pointless.

I agree that knowing which are VOR and which are LOC is not terribly
practical for most pilots, but knowing which are NAV and which are COM
is. I've seen more than one pilot keep spinning the knobs on the COM
radio trying to to figure out why they can't find 116.6 to get the
ATIS.

[John R. Copeland]

Well, Jim, it almost COULD work that way, but it doesn't. :-[
VOR azimuth angle is measured by a phase comparison
between two sinusoidal signals, not a time-delay measurement.
The VOR reference signal is frequency modulated on a subcarrier,
while the azimuth signal is from amplitude modulation on the
radio-frequency carrier, caused by the VOR's rotating cardioid beam.

Separately, DME distance is measured radar-like, by the time it takes
for the ground transponder to *reply* with a delayed pulse-pair
to an interrogation transmitted from the aircraft.

"Jim Macklin" > wrote in message news:vhDjg.137276$k%3.119945@dukeread12...
> You can explain how a VOR/DME works with a simple visual
> model.
>
> There is a large lake with an island in the middle. There
> is a lighthouse with a rotating beacon that makes one
> revolution a minute. It has a white beacon and a green
> beacon, when the white beacon is passing North, a big strobe
> light on top flashes and a very loud horn sounds.
>
> You see the strobe light flash and 6 seconds later see the
> green beacon sweep by. Where are you? 216 degrees from the
> beacon. Ten seconds after the strobe, you hear the horn,
> how far away? 2 miles.
>
> VOR is the same, just faster.
>
> --
> James H. Macklin
> ATP,CFI,A&P

[Jose]

>>1) He showed me disassembled instruments when describing how each works
>>> (how well can most of us explain how an altimeter really works inside,
>>> I thought a mag compass was ball shaped )
>
>
> I always thought it was worthwhile to show an instrument student a
> disassembled compass. Once he sees how the counterweight works to
> compensate for the vertical component of the magnetic field, turning
> errors are obvious - as well as why there are no turning errors while
> taxiing. Accelerationa and deceleration errors are equally obvious.

Calling Jay, calling Jay. Disassembled instruments would be way cool in
your aviation themed motel.

Jose
--
The price of freedom is... well... freedom.
for Email, make the obvious change in the address.

[Jose]

> Well, Jim, it almost COULD work that way, but it doesn't. :-[
> VOR azimuth angle is measured by a phase comparison
> between two sinusoidal signals, not a time-delay measurement.
> The VOR reference signal is frequency modulated on a subcarrier,
> while the azimuth signal is from amplitude modulation on the
> radio-frequency carrier, caused by the VOR's rotating cardioid beam.

It's indirect, but isn't a measurement of phase difference of two
different waves the same as the measurement of the time difference
between crests (once you take into account the frequency and the speed
of light)? It's like saying the alimiter measures altitude. It's not
technically correct (and yes, the difference is meaningful under some
circumstances) but gets the job done.

Jose
--
The price of freedom is... well... freedom.
for Email, make the obvious change in the address.

[John R. Copeland]

"Jose" > wrote in message . com...
>> Well, Jim, it almost COULD work that way, but it doesn't. :-[
>> VOR azimuth angle is measured by a phase comparison
>> between two sinusoidal signals, not a time-delay measurement.
>> The VOR reference signal is frequency modulated on a subcarrier,
>> while the azimuth signal is from amplitude modulation on the
>> radio-frequency carrier, caused by the VOR's rotating cardioid beam.
>
> It's indirect, but isn't a measurement of phase difference of two
> different waves the same as the measurement of the time difference
> between crests (once you take into account the frequency and the speed
> of light)? It's like saying the alimiter measures altitude. It's not
> technically correct (and yes, the difference is meaningful under some
> circumstances) but gets the job done.
>
> Jose
> --
>

The time domain and the frequency domain are related conventionally
through a mathematical manipulation called the Fourier Transform.
However, the measurement methods used in the two domains
are considerably different.
The VOR system was designed for measurements in phase space.
DME, of course, was designed for the time domain.

[Capt. Mike]

Who cares how it works ?

R u going to build one or fix one ?

Know how to operate the equipment and not how the equipment operater -

M.


"Robert M. Gary" > wrote in message
oups.com...
>
> Mitty wrote:
>> You might look at:
>>
>> http://www.dauntless-soft.com/PRODUCTS/RideReady/airplane.asp?DMODE=FAATEST
>>
>> I have used their software for written tests and found it to be very
>> good. I tried the "RideReady" Commercial oral package when it was
>> very new, a couple of years ago and at that time I thought it was kind
>> of weak.
>
> They don't appear to have anything for the CFII :(. As it turn out, my
> instructor knows an enourmous amount of stuff and I'm spending late
> nights learning stuff I never thought I'd know.
> 1) He showed me disassembled instruments when describing how each works
> (how well can most of us explain how an altimeter really works inside,
> I thought a mag compass was ball shaped )
> 2) He also explained how VORs really work (I thought they broadcast
> actual radials but they actually time the difference between a
> reference signal and a rotating sweeping signal).
> 3) He expects me to memorize the freq of markers and be able to
> distinguish a loc freq from vor freq by looking at the freq number.
> 4) Even the stuff I thought I knew was wrong. I thought lots of air was
> always running through the pitot tube and out the drain hole.
> Apparently only a very, very small amount of air comes out the back of
> the drain hole and the actual volume of air running through the pitot
> is very small. Looking at all the books, I got the impression air was
> just rushing through.
>
> -Robert
>

[Michael]

Robert M. Gary wrote:
> I understood that. I just way over estimated how much air went through
> the pitot tube. Any tube that has a hole in the front and a smaller
> hole in the back would do the job. The net pressure to the A/S
> indicator would be less but that's just a calibration issue. So I
> understood the concept but over estimated the flow.

Mea culpa. There was actually something you didn't know (or didn't
consider) but it was so obvious to me that I never even thought about
it. And really it's much less obvious than the physics - unless you
happen to routinely build and design stuff. I say this by way of
explanation and apology.

You're right - you could in theory have any tube with a bigger hole at
the front and a smaller one at the back, and the indication would be
less but could be calibrated out. There's a reason it's not done that
way, and it has nothing to do with the physics and everything to do
with manufacturing practices and standards.

ASI's are interchangeable, and it would be a maintenance nightmare not
to have them interchangeable. Imagine that every pitot tube had to
have its own matching (calibrated) ASI. Often the pitot tube is made
by the manufacturer. Fortunately they rarely fail, because
replacements are sometimes very expensive or even impossible to find.
Piper made its own pitot tubes for a long time. Go try to find one for
a short winger.

ASI's will all fail eventually. They're made with brass bellows that
are soldered together. The solder joints move and hold (just a little)
pressure. Eventually they are guaranteed to leak. The leak will show
up as a too-low airspeed indication.

So for practical purposes, you really need a pitot tube that supplies
approximately the right ram pressure.

Michael

[Michael]

Mark Hansen wrote:
> I thought this allowed rain water to drain as well. Otherwise, couldn't
> the water build up and eventually get into the pressure line to the
> ASI?

If there is a hole, then yes, it will drain water as well, because
there is flow into the tube. But without a drain hole, there is no air
flow into the pitot tube at all - so how will the rain drops get in? I
suppose if you flew through a heavy enough rain it could happen - but
that implies flying the plane IFR, and it's pretty rare for a plane to
be IFR capable and have no pitot heat. Rare, but not unknown.

Michael

[BTIZ]

I've used this analogy many times to explain VOR operation to students.. but
using one rotating beacon and the flash.. I like the idea of adding the horn
for the distance.

BT

"Mark Hansen" > wrote in message
...
> On 06/13/06 12:08, Jim Macklin wrote:
>> Just like the rotating beacon at the airport, the two lights are 180
>> apart and rotate on the common shaft.
>>
>> Yes, you could have just one light rotating, but two identifiable beacons
>> makes the system more useable and faster.
>>
>> English lesson... "white beacon passing North...green beacon sweeps by"
>> Seems that both are moving.
>
> Thanks, but I don't really need the English lesson.
> Your description made it sound like there were two rotating
> beacons, and I couldn't see why that was necessary to make
> the point. I asked the question so you could clarify.
>
> Having one rotating beacon seems to illustrate the functionality.
> If the point is to make the system easy for a student pilot to
> understand, why not keep it simple?
>
> The "useable[sic] and faster" issue isn't really necessary for
> the student to understand how the system works, IMHO :-)
>
> I do like the analogy, though.
>
> Thanks,
>
>
>>
>>
>>
>> "Mark Hansen" > wrote in message
>> ...
>> | On 06/13/06 11:15, Jim Macklin wrote:
>> | > You can explain how a VOR/DME works with a simple visual
>> | > model.
>> | >
>> | > There is a large lake with an island in the middle. There
>> | > is a lighthouse with a rotating beacon that makes one
>> | > revolution a minute. It has a white beacon and a green
>> | > beacon, when the white beacon is passing North, a big strobe
>> | > light on top flashes and a very loud horn sounds.
>> | >
>> | > You see the strobe light flash and 6 seconds later see the
>> | > green beacon sweep by. Where are you? 216 degrees from the
>> | > beacon. Ten seconds after the strobe, you hear the horn,
>> | > how far away? 2 miles.
>> |
>> | So are both the white and green beacons rotating?
>> |
>> | Don't you just need an omnidirectional strobe (with horn for
>> | distance measurements) and a single rotating beacon?
>> |
>> | >
>> | > VOR is the same, just faster.
>> | >
>> | >
>> | > Steer your boat so the bow always points to the light and
>> | > you've got an ADF homer.
>> | >
>> | >
>> | >
>> |
>> |
>> |
>> | --
>> | Mark Hansen, PP-ASEL, Instrument Airplane
>> | Cal Aggie Flying Farmers
>> | Sacramento, CA
>
>
>
> --
> Mark Hansen, PP-ASEL, Instrument Airplane
> Cal Aggie Flying Farmers
> Sacramento, CA

[BTIZ]

too difficult to comprehend for the beginning student who is not an
electronics major

BT

"John R. Copeland" > wrote in message
.. .
"Jose" > wrote in message
. com...
>> Well, Jim, it almost COULD work that way, but it doesn't. :-[
>> VOR azimuth angle is measured by a phase comparison
>> between two sinusoidal signals, not a time-delay measurement.
>> The VOR reference signal is frequency modulated on a subcarrier,
>> while the azimuth signal is from amplitude modulation on the
>> radio-frequency carrier, caused by the VOR's rotating cardioid beam.
>
> It's indirect, but isn't a measurement of phase difference of two
> different waves the same as the measurement of the time difference
> between crests (once you take into account the frequency and the speed
> of light)? It's like saying the alimiter measures altitude. It's not
> technically correct (and yes, the difference is meaningful under some
> circumstances) but gets the job done.
>
> Jose
> --
>

The time domain and the frequency domain are related conventionally
through a mathematical manipulation called the Fourier Transform.
However, the measurement methods used in the two domains
are considerably different.
The VOR system was designed for measurements in phase space.
DME, of course, was designed for the time domain.

[Robert M. Gary]

Capt. Mike wrote:
> Who cares how it works ?
>
> R u going to build one or fix one ?
>
> Know how to operate the equipment and not how the equipment operater -

I'm not sure if I'm spending hours with my instructor learning trivia
or useful stuff. However, this is a CFII and not an IR checkride so the
standard for understanding and being able to explain is different.

-Robert

[Jose]

> The time domain and the frequency domain are related conventionally
> through a mathematical manipulation called the Fourier Transform.

That may be true, but is also a ten dollar irrelevancy. The phase
difference directly relates to the time difference. Operationally, the
circiuitry employs phase relationships rather than a little man with a
fast stopwatch, but new pilots attempting to understand the concept of
VOR navigation don't need to understand RF electronics to "get" the idea
behind the VOR, especially in contrast to the ADF or DME. I find the
analogy completely apt.

> The VOR system was designed for measurements in phase space.
> DME, of course, was designed for the time domain.

This is a useful distinction for ciruit designers, but not for new pilots.

Jose
--
The price of freedom is... well... freedom.
for Email, make the obvious change in the address.

[Don Byrer]

On 13 Jun 2006 08:23:09 -0700, "Robert M. Gary" >
wrote:

>Mitty wrote:
>> You might look at:
>>
>> http://www.dauntless-soft.com/PRODUCTS/RideReady/airplane.asp?DMODE=FAATEST
>>
>> I have used their software for written tests and found it to be very
>> good. I tried the "RideReady" Commercial oral package when it was
>> very new, a couple of years ago and at that time I thought it was kind
>> of weak.
>
>They don't appear to have anything for the CFII :(.

Ahh...yes they do...it's part of the instrument rating s/w, not the
CFI/FOI package. I've used several of their test and oral prep
packages and found them to be extremely good value for the $$...
The oral exam (Ride Ready) preps still worth the $$, not quite as good
as the test preps.

--Don
Don Byrer
Radar Tech & Smilin' Commercial Pilot Guy
Amateur Radio KJ5KB
kj5kb-at-hotmail.com

"I have slipped the surly bonds of earth; now if I can just land without bending the gear..."
"Watch out for those doves...<smack-smack-smack-smack...>"

[Roy Smith]

In article >,
Jose > wrote:

> > The time domain and the frequency domain are related conventionally
> > through a mathematical manipulation called the Fourier Transform.
>
> That may be true, but is also a ten dollar irrelevancy. The phase
> difference directly relates to the time difference. Operationally, the
> circiuitry employs phase relationships rather than a little man with a
> fast stopwatch, but new pilots attempting to understand the concept of
> VOR navigation don't need to understand RF electronics to "get" the idea
> behind the VOR, especially in contrast to the ADF or DME. I find the
> analogy completely apt.

I honestly don't see why a pilot needs to know anything beyond, "A VOR
transmits 360 radials, and the NAV receiver can tell which one you're on".

Unlike some of the physics half-truths the FAA pushes, I can't see how this
little white lie could possibly get you into any operational trouble. It
doesn't get in the way of understanding VOR declination, or service
volumes, or scalloping due to signal reflections, or reverse sensing, or
the zone of confusion, or any of a number of little VOR gotchas that pilots
do need to be aware of.

[Michael]

Robert M. Gary wrote:
> > Know how to operate the equipment and not how the equipment operater -
>
> I'm not sure if I'm spending hours with my instructor learning trivia
> or useful stuff. However, this is a CFII and not an IR checkride so the
> standard for understanding and being able to explain is different.

I've been teaching instruments for a few years, and I think you're
learning useful stuff.

If you don't understand how the equipment operates, the only way you
can learn to operate the equipment is by rote. If you're always flying
with everything multiply redundant, always flying with the same stuff,
and can simply squawk anything out of the ordinary and make it someone
else's problem, you can get by that way if you're willing to memorize a
lot. It's an airline pilot sort of attitude. It doesn't work too well
in GA. The people we train often have only one of something, and thus
an understanding of how it works - and thus of the failure modes -
helps detect failures and understand their impact on the operation.
They usually pay for their own maintenance, and often participate in
the maintenance process, and thus being able to diagnose the failure is
valuable. They also upgrade equipment, and understanding how it works
means not needing to be retrained on every new item.

Michael

[John R. Copeland]

"Jose" > wrote in message . com...
>> The time domain and the frequency domain are related conventionally
>> through a mathematical manipulation called the Fourier Transform.
>
> That may be true, but is also a ten dollar irrelevancy. The phase
> difference directly relates to the time difference. Operationally, the
> circiuitry employs phase relationships rather than a little man with a
> fast stopwatch, but new pilots attempting to understand the concept of
> VOR navigation don't need to understand RF electronics to "get" the idea
> behind the VOR, especially in contrast to the ADF or DME. I find the
> analogy completely apt.
>
>> The VOR system was designed for measurements in phase space.
>> DME, of course, was designed for the time domain.
>
> This is a useful distinction for ciruit designers, but not for new pilots.
>
> Jose
> --

Jose, you asked and I answered. I didn't disagree with you.
The truth is out there for those who are interested.
But Jim's DME explanation was egregiously wrong, and shouldn't propagate.

[John R. Copeland]

"Roy Smith" > wrote in message ...
>
> I honestly don't see why a pilot needs to know anything beyond, "A VOR
> transmits 360 radials, and the NAV receiver can tell which one you're on".
>
> Unlike some of the physics half-truths the FAA pushes, I can't see how this
> little white lie could possibly get you into any operational trouble. It
> doesn't get in the way of understanding VOR declination, or service
> volumes, or scalloping due to signal reflections, or reverse sensing, or
> the zone of confusion, or any of a number of little VOR gotchas that pilots
> do need to be aware of.

This is usenet so we like to split hairs. :-)
VORs are not limited to "360 radials".
If you want to claim you navigate to 1/2-degree precision, or finer, VORs do that.
Personally, I try not to claim that ability, though. :-/