# HSI Question

#### jwp_145

##### GhostRider in the Sky
Hey guys,

I've looked through the 600 page G1000 Instructor Reference book from Garmin and cannot find this answer.

On the HSI's lateral deviation scale, rather than the standard circle and four dots, there are simply two dots on each side of the scale. I've also seen other HSIs like this too.

The Instrument Flying Handbook says that most lateral deviation scales are twelve degrees each side when fully deflected. So, am I correct to assume that each one of those dots is 4 degrees of deflection? The CDI on the second dot would be 8 degrees deflection, then full scale would be 12?

#### fish314

##### Well-Known Member
Hey guys,

I've looked through the 600 page G1000 Instructor Reference book from Garmin and cannot find this answer.

On the HSI's lateral deviation scale, rather than the standard circle and four dots, there are simply two dots on each side of the scale. I've also seen other HSIs like this too.

The Instrument Flying Handbook says that most lateral deviation scales are twelve degrees each side when fully deflected. So, am I correct to assume that each one of those dots is 4 degrees of deflection? The CDI on the second dot would be 8 degrees deflection, then full scale would be 12?
I don't know anything about the G1000, but my aircraft has an EHSI with two dots either side and each dot is 5 degrees, so that makes the second dot 10 degrees. I don't know about full scale deflection... I just say "more than 10 degrees".

#### Scandinavian13

##### New Member
I looked in the manual and it has 4 dots. It also references that it can be changed automatically, or manually, depending on your settings. Automatic revises the scale depending on the Flight Phase.

#### H46Bubba

##### Well-Known Member
Hey guys,

I've looked through the 600 page G1000 Instructor Reference book from Garmin and cannot find this answer.

On the HSI's lateral deviation scale, rather than the standard circle and four dots, there are simply two dots on each side of the scale. I've also seen other HSIs like this too.

The Instrument Flying Handbook says that most lateral deviation scales are twelve degrees each side when fully deflected. So, am I correct to assume that each one of those dots is 4 degrees of deflection? The CDI on the second dot would be 8 degrees deflection, then full scale would be 12?
Do you have the newest edition of the Instrument Flying handbook? If not the new addition has a buch of G1000 stuff in it.

R

#### Roger, Roger

##### Guest
Peg to peg with a VOR or LOC is the same as on a standard CDI, IIRC. With GPS it varies depending on which mode (enroute, terminal, lnav, lpv) it is in.

#### jwp_145

##### GhostRider in the Sky
I looked in the manual and it has 4 dots. It also references that it can be changed automatically, or manually, depending on your settings. Automatic revises the scale depending on the Flight Phase.
You are referring to the GPS nav source lateral deviation scale according to the ENROUTE, TERMINAL, or APPROACH Mode phases of flight. I know exactly which page you are referring to because I stared at it a lot yesterday.

And whoever asked about the new Instrument Flying Handbook, while it does use the G1000 for pictures, it doesn't have any information on that particular avionics suite. It simply uses the G1000 for the illustrations.

And I believe the person that said five degrees per dot had about the best suggestion. Thank you guys.

#### Yank&BankmyRJ145

##### New Member
Do what I do, Keep it centered!!:yup:

And if you do get off, let ATC know and ask for a vector-victor.