to HSI or not to HSI

Please excuse the hijacking of this religious/political forum to raise a
question about flying.

My partners and I are faced with a decision. What would you do?

We plan to update our outdated panel with a GNS480. The CDIs currently installed
are not compatible with the GNS480, so one of them will be replaced.

We could replace the existing CDI with a compatible one for $2000.

We could install a non-slaved NSD360 HSI instead for $3500.

If we install the HSI, the no-longer-used CDI hole can be used for the electric
AI that's been waaaay over on the other side of the panel.

I think I know what we will do (go for the HSI), but I'm collecting opinions.

Is the NSD360 likely to become a maintenance headache?

In the electronic age, does it make sense to install an electromechanical aid to
situational awareness?

Thanks,

Dave

This was heatedly discussed in the Cessna owners' group a
few months back. People seem to be completely polarised
about it. FWIW, I love my HSI and would hate to have to
fly without it. It was one of my key decision factors in
choosing a plane to buy. It just makes things SO much
easier as compared to a DI and a separate CDI. I've
flown a couple of times behind a Sandel electronic HSI
and that was even better, although I wouldn't pay
$10K to upgrade.

John

Dave Butler wrote:
Please excuse the hijacking of this religious/political forum to raise a
question about flying.

My partners and I are faced with a decision. What would you do?

We plan to update our outdated panel with a GNS480. The CDIs currently
installed are not compatible with the GNS480, so one of them will be
replaced.

We could replace the existing CDI with a compatible one for $2000.

We could install a non-slaved NSD360 HSI instead for $3500.

If we install the HSI, the no-longer-used CDI hole can be used for the
electric AI that's been waaaay over on the other side of the panel.

I think I know what we will do (go for the HSI), but I'm collecting
opinions.

Is the NSD360 likely to become a maintenance headache?

In the electronic age, does it make sense to install an
electromechanical aid to situational awareness?

Thanks,

Dave

"Dave Butler" wrote in message
...
Please excuse the hijacking of this religious/political forum to raise a
question about flying.

My partners and I are faced with a decision. What would you do?

We plan to update our outdated panel with a GNS480. The CDIs currently
installed are not compatible with the GNS480, so one of them will be
replaced.

We could replace the existing CDI with a compatible one for $2000.

We could install a non-slaved NSD360 HSI instead for $3500.

If we install the HSI, the no-longer-used CDI hole can be used for the
electric AI that's been waaaay over on the other side of the panel.

I think I know what we will do (go for the HSI), but I'm collecting
opinions.

Is the NSD360 likely to become a maintenance headache?

In the electronic age, does it make sense to install an electromechanical
aid to situational awareness?

Thanks,

Dave

Great question! Although I can't imagine flying without an HSI (all my
flying since my private checkride has been behind an HSI), it seems that
there will be a breakthrough soon. With some experemental PFDs selling for
under $2000 with AHARS, it seems that someone must be cooking up a
self-contained EHSI with internal gyro. I don't actually know of anyone
working on this but it seems unlikely that it is not being persued

Mike
MU-2

jharper aaatttt cisco dddooottt com opined

This was heatedly discussed in the Cessna owners' group a
few months back. People seem to be completely polarised
about it. FWIW, I love my HSI and would hate to have to
fly without it. It was one of my key decision factors in
choosing a plane to buy. It just makes things SO much
easier as compared to a DI and a separate CDI. I've
flown a couple of times behind a Sandel electronic HSI
and that was even better, although I wouldn't pay
$10K to upgrade.

I love my HSI! But it might be better to wait and save for a glass panel.

Should the best be the enemy of the the good?

Dave Butler wrote:
Please excuse the hijacking of this religious/political forum to raise a
question about flying.

My partners and I are faced with a decision. What would you do?

We plan to update our outdated panel with a GNS480. The CDIs currently
installed are not compatible with the GNS480, so one of them will be
replaced.

We could replace the existing CDI with a compatible one for $2000.

We could install a non-slaved NSD360 HSI instead for $3500.

If we install the HSI, the no-longer-used CDI hole can be used for the
electric AI that's been waaaay over on the other side of the panel.

I think I know what we will do (go for the HSI), but I'm collecting
opinions.

Is the NSD360 likely to become a maintenance headache?

In the electronic age, does it make sense to install an
electromechanical aid to situational awareness?

Thanks,

Dave




-ash
Cthulhu in 2005!
Why wait for nature?

Dave Butler wrote
If we install the HSI, the no-longer-used CDI hole can be used for the electric
AI that's been waaaay over on the other side of the panel.

Actually, if your primary AI is vacuum and the secondary is electric,
you can simply remove the T&B and install the second AI in its place.
AC91-75 permits the replacement of the T&B with a second AI, as long
as the power source for the 2nd AI is different from the power source
for the 1st AI. So really, being able to free up the hole should not
factor into your decision.

Some people love HSI's, some hate them, some are indifferent. I've
flown several planes with HSI's and I'm indifferent. It's OK. A DG
with CDI is also OK. About the only time an HSI really has an
advantage is when you're flying reverse course on a localizer. Other
than in training, I do not believe I have ever had to do that.

Michael

Dave,
My NSD 360A ran fine for about 9 years then just died. I sent it back to
the factory. Told me nothing wrong. Lousy service. I have an old soon to
be rebuilt NSD360A for sale. Interested? I upgraded to a Sandel.
Michelle

Dave Butler wrote:

Please excuse the hijacking of this religious/political forum to raise
a question about flying.

My partners and I are faced with a decision. What would you do?

We plan to update our outdated panel with a GNS480. The CDIs currently
installed are not compatible with the GNS480, so one of them will be
replaced.

We could replace the existing CDI with a compatible one for $2000.

We could install a non-slaved NSD360 HSI instead for $3500.

If we install the HSI, the no-longer-used CDI hole can be used for the
electric AI that's been waaaay over on the other side of the panel.

I think I know what we will do (go for the HSI), but I'm collecting
opinions.

Is the NSD360 likely to become a maintenance headache?

In the electronic age, does it make sense to install an
electromechanical aid to situational awareness?

Thanks,

Dave


--

Michelle P ATP-ASEL, CP-AMEL, and AMT-A&P

"Elisabeth" a Maule M-7-235B (no two are alike)

Volunteer Pilot, Angel Flight Mid-Atlantic

Volunteer Builder, Habitat for Humanity

FWIW, the GNS480 displays an electronic HSI on its NAV page. I also plan to upgrade my panel with the GNS480, but after spending $11K on the GPS I can't justify spending more on a HSI that doesn't add that much extra. The NSD360 was the cheapest HSI I could find but after some research it seemed like a problem instrument. This quote is from the Avionics West article at http://avionicswest.com/articles/kno..._autopilot.htm

"The most popular Cessna HSI today is the Edo-Aire NSD-360 series. Cessna installed these units in thousands of single and multi-engine aircraft. This compass system is slaved in most cases, but be advised there are many non-slaved NSD-360's in the field. Even with a slaved NSD-360, you must set the compass card once the aircraft is running. After that if everything is working as it should, you shouldn't have to set the compass card again. This HSI, slaved or not, MUST have BOTH vacuum and electrical inputs in order to operate. In other words, if you lose vacuum or the electrical system, this HSI compass card will quit! Expect to pay between $300-500/year to keep your NSD repaired. Sure, you may not need a repair for several years but when your unit does, it really hits the ole pocket book "

This next quote is from an AVWEB article at http://www.avweb.com/news/reviews/182525-1.html

"Not long thereafter, my vacuum-driven NSD-360 HSI started acting up. On several occasions, the slaved heading gyro suddenly wound up 20 or 30 degrees in error, causing the autopilot to take me on an unplanned off-route excursion each time. Although I subsequently diagnosed the problem as being a clogged central vacuum filter, it reminded me that the NSD-360 was a pretty vulnerable instrument, and one that had required (and would continue to require) overhauls every few years at a cost of around $2,800 a pop. Somehow, that made the $8,000 price of the Sandel seem a lot more reasonable. "

So that finished me on the NDS360 and all the other HSI's were way too expensive. I'm going to keep my DG and get a new MD200 CDI to go with the GNS480.

-Brenor

"Dave Butler" wrote in message ...
Please excuse the hijacking of this religious/political forum to raise a
question about flying.

My partners and I are faced with a decision. What would you do?

We plan to update our outdated panel with a GNS480. The CDIs currently installed
are not compatible with the GNS480, so one of them will be replaced.

We could replace the existing CDI with a compatible one for $2000.

We could install a non-slaved NSD360 HSI instead for $3500.

If we install the HSI, the no-longer-used CDI hole can be used for the electric
AI that's been waaaay over on the other side of the panel.

I think I know what we will do (go for the HSI), but I'm collecting opinions.

Is the NSD360 likely to become a maintenance headache?

In the electronic age, does it make sense to install an electromechanical aid to
situational awareness?

Thanks,

Dave

"Michael" wrote in message
om...
Dave Butler wrote
If we install the HSI, the no-longer-used CDI hole can be used for the
electric
AI that's been waaaay over on the other side of the panel.

Actually, if your primary AI is vacuum and the secondary is electric,
you can simply remove the T&B and install the second AI in its place.
AC91-75 permits the replacement of the T&B with a second AI, as long
as the power source for the 2nd AI is different from the power source
for the 1st AI. So really, being able to free up the hole should not
factor into your decision.

Some people love HSI's, some hate them, some are indifferent. I've
flown several planes with HSI's and I'm indifferent. It's OK. A DG
with CDI is also OK. About the only time an HSI really has an
advantage is when you're flying reverse course on a localizer. Other
than in training, I do not believe I have ever had to do that.

Can you explain why that is the one advantage (BC)/revers on localizer, and
why that is so?
Do you mean to say that people confuse which color sector they are in on a
localizer due to "reverse needle"? If so then it is a training issue, not a
technology issue.


Michael

In article ,
Richard Hertz no one@no one.com wrote:
Can you explain why that is the one advantage (BC)/revers on localizer, and
why that is so?

An HSI is like a CDI you can spin around. When shooting a back course
it is effectively upside down, cancelling out the reverse sensing.

--
Ben Jackson

http://www.ben.com/

I would rather have an IFR GPS and an autopilot, than VOR/GS and DME
and an HSI.
But, heck, if you have the money, go ahead and get an HSI. You might
consider waiting until you have mastered the IFR GPS. Also, one REALLY
NICE thing about an HSI is most are slaved. No more worrying about
your DG accuracy when ATC gives you vectors. Nonslaved not quite as
satisfying. Slaved ones are $$$.

The autopilot is really nice on long trips, IFR or VFR and, if a
totally electric autopilot, a real safety device in IMC. They are
expensive and need maintenance though.

Dave Butler wrote in message ...
Please excuse the hijacking of this religious/political forum to raise a
question about flying.

My partners and I are faced with a decision. What would you do?

We plan to update our outdated panel with a GNS480. The CDIs currently installed
are not compatible with the GNS480, so one of them will be replaced.

We could replace the existing CDI with a compatible one for $2000.

We could install a non-slaved NSD360 HSI instead for $3500.

If we install the HSI, the no-longer-used CDI hole can be used for the electric
AI that's been waaaay over on the other side of the panel.

I think I know what we will do (go for the HSI), but I'm collecting opinions.

Is the NSD360 likely to become a maintenance headache?

In the electronic age, does it make sense to install an electromechanical aid to
situational awareness?

Thanks,

Dave