HSI Question

[Pilot12345]

Can someone give me the basics of an HSI? And also what does the slave / free function do? I've never used an HSI, but am going to get checked out in a plane that has one. Just wanted to get a heads up on what to expect. Thanks!

 

[minitour]

Basics?

It's like a VOR/LOC (possibly GS) tossed on top of a DG...good for situational awareness.

Now the slave/free thing...no idea.

You can use them to avoid "reverse sensing" on back course approaches which can be nice...

I guess there's a trick with them to doing DME Arcs, but...I haven't really had a problem doing DME arcs with just a DME indicator...this turn 10 twist 10 confuses me more than its worth

Thats all I got...

-mini

 

[User546]

http://www.avionix.com/hsi.html
The first five paragraphs of this page gives you a good overview of what an HSI does, and also touches on the "slaved" version as well. At the bottom of the page they will break down each part of the HSI and it's function. Will help with quick familiarization. Chances are the HSI type that you will use will be the Bendix/King KCS-55A HSI one that's halfway down the page.

http://hsi.idoneos.com/
I also found this, which is a little java script HSI simulator. Gives you a rough idea.

If you have Microsoft Flight Sim 2004, use an airplane that has an HSI in it and do some instrument practice.

Once you get comfortable with an HSI, you'll never want to go back to the traditional VOR gauge!

 

[minitour]

Once you get comfortable with an HSI, you'll never want to go back to the traditional VOR gauge!

I'll say! One of our RGs has an HSI...granted its INOP, but I still never want to go back to a "normal" OBS for my LOC/GS indicator.

Just seems like flying an ILS with an HSI and RMI would be SOOOOOOOOOOOO easy...just tune, ID and away we go!

 

[User546]

Just seems like flying an ILS with an HSI and RMI would be SOOOOOOOOOOOO easy...just tune, ID and away we go!

Tune, and ID?? Ahh come on, thats not real world Mini!! Be sure and tell the examiner that gives you your CFII that User997 told you that!

Since you seem to love the DME arcs, you can't fly a more perfect DME arc then when you use an RMI. All you have to do is just keep the needle 90 degrees off your nose, pointed in the direction of the station, and you'll have it nailed.

 

[minitour]

Tune, and ID?? Ahh come on, thats not real world Mini!! Be sure and tell the examiner that gives you your CFII that User997 told you that!

Since you seem to love the DME arcs, you can't fly a more perfect DME arc then when you use an RMI. All you have to do is just keep the needle 90 degrees off your nose, pointed in the direction of the station, and you'll have it nailed.

Love those DME Arcs...not to threadjack but...what's with the turn 10 twist 10 thing? I've always had a picture in my mind of where the station is and which way I need to turn to keep the DME around the right number...don't get the turn 10 twist 10 thing

-mini

 

[Metro752]

its a process used to stay on course

 

[midlifeflyer]

mini, I think you're essentially correct about "turn 10, twist 10"). If you watch the DME readout and make adjustments based on what it says, the "turn 10" doesn't make much sense. The "twist 10" is really just to monitor your progress along the arc. It doesn't have to be 10, but getting used to twisting the dial for monitoring is not a bad idea. Might even come in handy on an approach like the always-fun VOR/DME RWY 15 at Martin State: http://naco.faa.gov/d-tpp/0502/05222VDTZ15.PDF

 

[soarby007]

Slave or free? That only applies when you cross the Mason Dixon line.
Be sure and flip the switch then.

This relates to the slaved gyro. If it doesn't match your compass, then put it in free and turn it to match. Or if the slave doesn't work, operate in free and it's just like a regular old time Heading indicator.

 

[Lead Sled]

Slave or free? That only applies when you cross the Mason Dixon line. Be sure and flip the switch then.

Boy, am I ever glad that he didn't ask about the "Fast Erect" button!

'Sled

 

[minitour]

Might even come in handy on an approach like the always-fun VOR/DME RWY 15 at Martin State: http://naco.faa.gov/d-tpp/0502/05222VDTZ15.PDF

SWEET!!!

See, that's why I love instrument flight...approaches like that one.

That just looks like fun!

But on that one, couldn't I just set the radials for the intersections and when I get to them, set the next one? Just keep monitoring the DME.

All I've been doing lately (in an FTD) is setting the inbound course and when it starts coming in, I continue my turn to intercept. So far its worked...any opinions on if it'll continue to work on bigger/faster shtuff?

-mini

 

[TDTURBO]

This is a great little site to learn ADF, HSI VOR stuff. It actually is interactive. Try it, it's really cool.


http://www.visi.com/~mim/nav/


also try this.

http://stoenworks.com/Tutorials/HSI,%20the%20complete.html

 

[Hung Start]

TD:


Those are excellent links. Thanks

 

[troy]

There are several navigation sims here, including an HSI

http://www.russellaviation.com/navsims.htm

 

[TDTURBO]

TD:


Those are excellent links. Thanks

No problem Hung Start, if you need any other cool and easy to understand learning aids, let me know.

 

[Swerpipe]

One Special Feature...

HSIs have one special feature that many pilots miss. When you are on an intercept heading and the course becomes alive, you should wait until the "needle" touches the line from vertical (lubber line) and then turn (left or right) to keep these two lines touching each other as you intercept course. To keep these two lines "touching" each other you will need to vary your bank angle from small intitially then larger then smaller. What is great is that the HSI will "coordinate" your turn as you intercept the localizer just like a flight director would.
I realize the difficulty of explaning this without a video or a live sim in front...

 

[fokkers&beer]

The slave and free thing have to do with coupling it to the flux compass. Flux compass don't work, put it in free, adjust it and it works like a DG, no automatic north capabilities.

 

[Tinstaafl]

There's a slight catch to be aware of when keeping the lubber line in contact with the CDI: If there's a signifcant wind from the other side of the desired course ie a x-wind once on course that was pushing you away from the track & not towards it, then eventually the HDG achieved while keeping the two points aligned will be the wind correction angle & the a/c will parallel the desired course instead of intercepting it.

The good news is that once you achieve track you'll already know what drift allowance you'll need.