Make a case in favor of adding an HSI

Jaybird180

Jaybird180

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Jaybird180
What does an HSI buy you in terms of IFR simplicity or SA for a 6-pack equipped /G airplane?

I know a few if you have one installed.
 
Simplifies your scan by combing the CDI/GS and the HI. It is by no means a requirement to safely fly IFR, but it sure does make the scan easier I think.
 
Jaybird180 said:
What does an HSI buy you in terms of IFR simplicity or SA for a 6-pack equipped /G airplane?

I know a few if you have one installed.
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I have one, it's nice to have, no way I buy one with Aspens on the market.
 
I have an HSI, but frankly it's pretty darn convenient to just stare at the purple line to get a real depiction.
 
If you don't have a purple line, it's good. But a purple line is better.
 
I have an HSI. The "S" part is pretty overrated. It does outstanding at the "I" part, but after-all, it still is a round ball thing with a gob of numbers and a lubber line(not sure if that's the right aviation term). I prolly wouldn't pony up for one in this day.
 
They're nice as you can see what would otherwise not be visible on one instrument (HI and CDI). Honestly though, I've never really cared that much about whether or not an airplane has one and certainly wouldn't pay to put one in.

These days though, it makes little sense to put a HSI in when you can put an Aspen in.
 
Unless you are getting some magnificent deal on an HSI, you can get an Aspen with an EHSI and more for less money.
 
Fearless Tower said:
For an ILS, I'd take an HSI over the magenta line.
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Same here. And also generally, for the precision ATC expects of me when IFR, I'd rather fly the CDI. Yes it can be done with the magenta line, but only by zooming way in. I like to have the big picture on the MFD (or at least, larger than a half mile square).

As far as what others have said about the HSI combining the functions of the DG and the CDI, that's all true but the whole is greater than the sum of its parts. It lets you easily visualize your heading and position relative to the desired course. Only a moving map/magenta line does that better, and when I'm less than full scale deflection, I much prefer the HSI.
 
I have an HSI and love it for the benefits Fearless listed. But if it breaks, I'm buying an aspen.

I don't think it makes sense to add a new one with the aspen out there though.
 
I never used one myself but I've flown with friends that had 'em. Back before the days of moving maps and magenta lines I think they helped somewhat in maintaining (visualizing) situational awareness, seemed to be quite helpful for guys that had trouble with flying the Localizer BackCourse. Yesterdays technology, I always thought an RMI would be even more helpful, especially for DME Arcs and NDB approaches (also yesterdays technology) but never had one of them either.
 
For situational awareness, how about a Garmin handheld in "faux HSI" mode?

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Added benefit of a "faux glideslope" for managing descents.
 
Simplifies your scan by combing the CDI/GS and the HI.
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+1

I like 'em, mechanical or electronic. What I don't like is that the G1000 designers did not include the glide slope in their HSI. I guess that they expect you to be watching for DA anyway, so it's OK to put GS with the altitude tape.

IMHO (and I expect to get bashed), flying the magenta line is sloppy piloting. Course accuracy depends on the map scale. Why do it when you've got a perfectly good CDI or HSI where you know what the needle deflection means?
 
LDJones said:
+5

If you're going to do it, do it right. The Aspen sets you up for future upgrade ability.
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I see the point, but it is $10k MSRP.
I thought an HSI could be had for (don't laugh)...a couple hunnit bux
 
A new HSI installed is going to cost nearly 75% of an Aspen and the Aspen provides far more. But a lot of HSIs are coming onto the used market due to glass upgrades and one of those might be affordable, especially if you can do some of the installation grunt work.
 
Do talk to your avionics shop about installation, parts & labor. THEN decide . . . .
 
HSI parts 'n' pieces are showing up cheap, but look at what is involved in proper installation of and HSI and you'll know... The days of new installs of HSIs at retail are surely over.

I love mine, but like others said, when mine fails, it is Aspen time.
 
FastEddieB said:
For situational awareness, how about a Garmin handheld in "faux HSI" mode?

296b.jpg
Click to expand...

That's silly. The map itself is much better for situational awareness than an HSI (either real or imagined). This suggestion is akin to the electronic E6B app I have on my iPhone that gives you a graphical presentation of an actual mechanical E6B.

The nice thing about the HSI is putting the needles right in front of the pilot, it's situational awareness features are really archaic even with regard to early generation moving maps (like for example the eventide)
 
flyingron said:
That's silly. The map itself is much better for situational awareness than an HSI (either real or imagined).
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Well, call me silly then.

In this marvelous new world we find ourselves in, I now have a magenta line on my iPad I can just stay on. Cool!

But...

...maybe it's the years of flying with mostly a Heading Indicator, and only occasionally an HSI, but for the most part I do use the "faux HSI" on the 496 as primary nav source, VFR in my case. I also use the moving map on my iPad for airspace and the like, but not usually for primary navigation.

But I can see how a new or more adaptable pilot could just go 100% moving map, and maybe I will as well, eventually.

Old dogs and new tricks and all that! ;)
 
FastEddieB said:
Well, call me silly then.

In this marvelous new world we find ourselves in, I now have a magenta line on my iPad I can just stay on. Cool!

But...

...maybe it's the years of flying with mostly a Heading Indicator, and only occasionally an HSI, but for the most part I do use the "faux HSI" on the 496 as primary nav source, VFR in my case. I also use the moving map on my iPad for airspace and the like, but not usually for primary navigation.

But I can see how a new or more adaptable pilot could just go 100% moving map, and maybe I will as well, eventually.

Old dogs and new tricks and all that! ;)
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Thing is it's quite limited to use, a VFR GPS display. The thing about a magenta line alone is there is no vertical guidance. As you note, IFR ops are dubious at best.
 
SCCutler said:
HSI parts 'n' pieces are showing up cheap, but look at what is involved in proper installation of and HSI and you'll know... The days of new installs of HSIs at retail are surely over.

I love mine, but like others said, when mine fails, it is Aspen time.
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Agree. I wouldn't substitute the magenta line on approaches--just not accurate enough. But aside from that, it isn't a big deal to use two gauges instead of one, until you can go to Aspen or glass.
 
When i learned to fly ifr, the great value of an hsi over separate heading and indicator instruments was the ease of laying a pencil on the instrument and getting a heading to navigate point-point off-airway. Does that sound useful in todays world?
 
I didn't say fly the magenta line, I said to use it for situational awareness. What does the S stand for (and the whole point of mounting the vacuum tube era CDI over a mechanical spinning wheel) in the HSI?
 
Depending on the HSI, it can take up to 40 hours to get it installed. The Century NSD360 is the cheapest to install from a labor perspective. It comes with and without slaving. The KFC55A has more components and often only the indicator is available, which means you have to also purchase the remote gyro, slaving accessory, and remote magnetometer. Some come with a feature called Bootstrap, which provides an analog signal output of heading when interfaced with some avionics such as a Stormscope. It is an expensive add on if you need to add it later. Overhauling the system can also be very expensive.

An Aspen is far and away a better option.
 
One other advantage for me (over a plain DG) is that the HSI is slaved to a remote flux gate. When I started my IFR training, the DG in one of the rental 172s I was using precessed like crazy (The owner was too cheap to get it fixed). It was off by 10 degrees every 15 minutes. Spent most of my time constantly resetting the darn thing to match the compass. This particular 172 also had an AI which indicated a slight turn to the right in level flight. Combine that effect with the precessing DG, and it was "interesting" to say the least. I only flew that thing in actual IMC once and said never again. Not a good training situation.

Then I bought my own plane which has an HSI built in and finished my training in it. Loved the fact that I didn't have to do anything more than confirm the heading and compass agreement on a regular basis.

The other 172 that I occasionally used had an old autopilot which would occasionally command a hard left turn for no reason. :yikes: Particularly annoying when this happened while practicing coupled approaches! I did build some good "trust but verify" habits with the trust level being pretty much nil.

All that said, If I were planning to purchase a new piece of equipment, I'd plan to spend the money on an Aspen instead adding an HSI.
 
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