Replacement DG & AI: Suggestions?

[Andrew Gideon]

One of our club aircraft, as a result of water damage, needs a new AI and
DG. But rather than just replacing the units with the same type, we're
going to give careful consideration to the possibility of an upgrade.
Since this is prime flying time, I've been given an entire day to collect
possibilities.

So...what are the possibilities?

I briefly considered suggesting that we ditch the entire panel and put in an
Avidyne. But that doesn't really help, as we'd still need "steam gauge"
backups. So, sadly, I put that behind me.

A quick search of my notes (I've been day dreaming for a while {8^) found
products like:

http://www.pcflightsystems.com/EGYRO2.htm
http://www.lifesavergyro.com/technical_home.html

for the AI, but I'm curious what other options exist and what
suggestions/opinions people here would have to offer. I am also starting
from scratch WRT the DG. HSI? I seem to recall seeing something about a
"digital" HSI that had some other interesting features.

Thanks...

Andrew

[Paul kgyy]

Aviation Consumer mag says the digital HSI hasn't lived up to its
expectations.

Stec has excellent gyros, and they're not that expensive. Then add a
Midcontinent electric AI.

[Andrew Gideon]

Paul kgyy wrote:

> Aviation Consumer mag says the digital HSI hasn't lived up to its
> expectations.
>
> Stec has excellent gyros, and they're not that expensive.

STEC has gyros? I don't see that on their web site. All I see are
autopilots.

Did you perhaps mean Sigma Tek?

- Andrew

[Mike Rapoport]

The one suggestion that I would make is, if you get vacuum gyros, get ones
with vacuum flags.

Mike
MU-2


"Andrew Gideon" > wrote in message
online.com...
>
> One of our club aircraft, as a result of water damage, needs a new AI and
> DG. But rather than just replacing the units with the same type, we're
> going to give careful consideration to the possibility of an upgrade.
> Since this is prime flying time, I've been given an entire day to collect
> possibilities.
>
> So...what are the possibilities?
>
> I briefly considered suggesting that we ditch the entire panel and put in
> an
> Avidyne. But that doesn't really help, as we'd still need "steam gauge"
> backups. So, sadly, I put that behind me.
>
> A quick search of my notes (I've been day dreaming for a while {8^) found
> products like:
>
> http://www.pcflightsystems.com/EGYRO2.htm
> http://www.lifesavergyro.com/technical_home.html
>
> for the AI, but I'm curious what other options exist and what
> suggestions/opinions people here would have to offer. I am also starting
> from scratch WRT the DG. HSI? I seem to recall seeing something about a
> "digital" HSI that had some other interesting features.
>
> Thanks...
>
> Andrew
>

[Paul kgyy]

Sorry, yes, Sigma Tek :-(

[Ron Natalie]

Paul kgyy wrote:
> Aviation Consumer mag says the digital HSI hasn't lived up to its
> expectations.

The real problem is that there isn't a real good digital HSI SYSTEM.
The few out there while using digital indicators still use the same
old clunky remote gyro/fluxgate stuff which hasn't progressed much in
20 years.

[Ron Natalie]

Andrew Gideon wrote:

>
> STEC has gyros? I don't see that on their web site. All I see are
> autopilots.
>
> Did you perhaps mean Sigma Tek?

Sigma Tek is the main gyro manufacturer, but S-Tec does make an HSI.

[Andrew Gideon]

So has anyone flown behind, or looked into, the Mid-continental "Lifesaver"?
It claims to be certified as a primary AI. And the MBTF, at 7500 hours, is
well beyond what would expect from a vacuum-driven AI.

It's more expensive, but less so "per hour". So it seems a reasonable
investment.

However, it's an electrical device. So is our Turn Coordinator. Lose
electrical power in IMC, and...

The "lifesaver" can have a backup battery which claims to provide an hour of
power.

But would you want to fly in an airplane with a standard electrical system
(ie. no dual alternator/dual battery as in a true "all electric" airplane)
with an electric TC and AI, even with an hour of backup power on the AI?

It makes me a little nervous. Am I being luddite-ish?

- Andrew

P.S. Just for reference, I should add that the club aircraft
all have Precise Flight's standby vacuum system.

[Michael R]

Another possibility:


http://www.sportys.com/acb/showdetl.cfm?&Product_ID=7439&DID=19





"Andrew Gideon" > wrote in message
online.com...
>
> One of our club aircraft, as a result of water damage, needs a new AI and
> DG. But rather than just replacing the units with the same type, we're
> going to give careful consideration to the possibility of an upgrade.
> Since this is prime flying time, I've been given an entire day to collect
> possibilities.
>
> So...what are the possibilities?
>
> I briefly considered suggesting that we ditch the entire panel and put in
> an
> Avidyne. But that doesn't really help, as we'd still need "steam gauge"
> backups. So, sadly, I put that behind me.
>
> A quick search of my notes (I've been day dreaming for a while {8^) found
> products like:
>
> http://www.pcflightsystems.com/EGYRO2.htm
> http://www.lifesavergyro.com/technical_home.html
>
> for the AI, but I'm curious what other options exist and what
> suggestions/opinions people here would have to offer. I am also starting
> from scratch WRT the DG. HSI? I seem to recall seeing something about a
> "digital" HSI that had some other interesting features.
>
> Thanks...
>
> Andrew
>

[Andrew Gideon]

Michael R wrote:

> Another possibility:
>
>
> http://www.sportys.com/acb/showdetl.cfm?&Product_ID=7439&DID=19

I first read of this in a CPA email message. But they didn't provide a URL.

This instrument is interesting. It's apparently not solid state, but
instead uses the "old" approach of an electrically spun gyro (as most TCs
do). Therefore, I'd expect it to live less long than the Mid-continental
solid-state "equivalent".

But the Mid-continental has but a single year warranty. So...?

And this is cheaper by a factor of about four. However, it lacks an
electrical backup. So I'd not want to use it as a replacement for an AI in
my aircraft, where an electrical loss would mean losing both AI and TC.

Instead, this appears intended as a TC replacement. And that raises some
questions.

First, what about rate-based autopilots? How would they work where there
was no device reporting on the rate of a turn?

Second is the loss of the ability to do a timed turn. Perhaps this is no
big deal, as that's something we do only when the AI has failed.
Interesting.

Third, how would I go about determining if I could replace a TC with this in
one of my club aircraft (which all fly IFR)? I understand STCs, which are
model specific. Do I need to find an STC for a 172 or 182 for this?

Or does the fact that this is "TSOed" eliminate the need for an STC? Would
a field approval still be required, or not?

[And on the same theme: is there something I can read that discusses all
these concepts: PMA, STC, TSO, field approvals, etc.? I feel like I'm
groping my way in the dark on these. It sounds like the perfect topic for
a FAQ or tutorial for the O in AOPA.]

Thanks...

Andrew

[Mark Hansen]

On 4/19/2005 09:33, Andrew Gideon wrote:

> Michael R wrote:
>
>> Another possibility:
>>
>>
>> http://www.sportys.com/acb/showdetl.cfm?&Product_ID=7439&DID=19
>
> I first read of this in a CPA email message. But they didn't provide a URL.
>
> This instrument is interesting. It's apparently not solid state, but
> instead uses the "old" approach of an electrically spun gyro (as most TCs
> do). Therefore, I'd expect it to live less long than the Mid-continental
> solid-state "equivalent".
>
> But the Mid-continental has but a single year warranty. So...?
>
> And this is cheaper by a factor of about four. However, it lacks an
> electrical backup. So I'd not want to use it as a replacement for an AI in
> my aircraft, where an electrical loss would mean losing both AI and TC.
>
> Instead, this appears intended as a TC replacement. And that raises some
> questions.
>
> First, what about rate-based autopilots? How would they work where there
> was no device reporting on the rate of a turn?
>
> Second is the loss of the ability to do a timed turn. Perhaps this is no
> big deal, as that's something we do only when the AI has failed.
> Interesting.

The information on the Sporty's page talked about putting this in
the TC's position and moving the TC to a different location in the
panel.

[ snip ]


>
> Thanks...
>
> Andrew
>
>


--
Mark Hansen, PP-ASEL, Instrument Student
Sacramento, CA

[Andrew Gideon]

Mark Hansen wrote:

> The information on the Sporty's page talked about putting this in
> the TC's position and moving the TC to a different location in the
> panel.

The cited AC mentions that too, I believe, as one solution. But I'm trying
to simplify the aircraft. I want to *replace* (and enhance); not just
*add*.

The AC also mentions other solutions for a rate-based AP, but they're all
along the lines of "don't do that" <grin>.

- Andrew