One GI275 enough for legal VFR?

TimRF79

TimRF79

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The GI 275 attitude indicator has Airspeed and Altitude indication.
Does that mean that one GI275 AI is enough to fly legal VFR, assuming your engine information (Tach, MP, OilP, Oil Temp, Fuel Gauge)?
 
TimRF79 said:
The GI 275 attitude indicator has Airspeed and Altitude indication.
Does that mean that one GI275 AI is enough to fly legal VFR, assuming your engine information (Tach, MP, OilP, Oil Temp, Fuel Gauge)?
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Does the Altitude indication come from GPS or an Altimeter. Ya gotta have an Altimeter
 
luvflyin said:
Does the Altitude indication come from GPS or an Altimeter. Ya gotta have an Altimeter
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In the manual it states :"The Altimeter displays barometric altitude"
So yes, it works of a Pitot-Static system
 
luvflyin said:
Sounds like yer good to go. FAR 91.205 tells you what you need.
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I am aware of 91.205, and that leads me to believe it should be fine.
However, thought I would tap into the "hive-brain"
 
What does the STC and installation manual tell you? It'll tell you what it can legally replace and what you have to retain instrument-wise. I doubt it's certified as a primary replacement airspeed indicator or altimeter (the G5 isn't).
 
A second altimeter and airspeed indicator will be required.
 
I believe this answers my question:
upload_2021-5-26_14-25-20.png

This seems to state that ONE GI275 ADI is sufficient for VFR operation.
A second GI275 HSI with Standby ADI is required for IFR operation.
Also ONE GI275EIS would be sufficient for all engine data.

If someone has a different view, please let me know.

source link":
https://www.pilotshop.com/catalog/avpages/garmin_gi275cdimfd.php
 
Clip4 said:
what VFR aircraft do you know of with only an electronic altitude display?
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Cessna 162. Not that your question is logical in the first place. Just because you can’t name one doesn’t mean they are required.
 
For some reason I thought if you had an electronic ADI you need a second one as well (electronic or vacuum). But you don't need a back up if you have a vacuum driver ADI - which given the reliability of the two makes no sense to me.

Perhaps it might just be that the second electronic ADI (like a G5) was needed in addition to the G3 glass panel to drive the auto pilot.

Here is a snap of the Glass Tiger.
 

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A few things,
The G5 was only a primary for AI or TC
From what I see GI275 is primary for AI, Airspeed and Altimeter.

I am asking about legal (not smart or advisable)
 
TimRF79 said:
I believe this answers my question:
View attachment 96707

This seems to state that ONE GI275 ADI is sufficient for VFR operation.
A second GI275 HSI with Standby ADI is required for IFR operation.
Also ONE GI275EIS would be sufficient for all engine data.

If someone has a different view, please let me know.

source link":
https://www.pilotshop.com/catalog/avpages/garmin_gi275cdimfd.php
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You need to review the actual installation manual (which will be hard to find without a friendly dealer; a quick Google search doesn't lead to any leaked copies). It will have a limitations section that tells you what it can and cannot replace. The AFMS isn't intended to have THAT kind of data in it.
 
bradg33 said:
You need to review the actual installation manual (which will be hard to find without a friendly dealer; a quick Google search doesn't lead to any leaked copies). It will have a limitations section that tells you what it can and cannot replace. The AFMS isn't intended to have THAT kind of data in it.
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Thanks for noting that the install manual is not readily available, as you noticed I googled a bit...
So this then makes my post actually a very good question as it requires someone with access to an installation manual to comment.
 
TimRF79 said:
install manual is not readily available,
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Maybe call Garmin direct with question or a large Garmin dealer like Sarasota. Garmin STC docs and install manual sometimes tough to come by.
 
TimRF79 said:
Thanks for noting that the install manual is not readily available, as you noticed I googled a bit...
So this then makes my post actually a very good question as it requires someone with access to an installation manual to comment.
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If you have an account on Beechtalk, there are a few threads discussing the install manual and a few folks expressed a willingness to privately provide a copy. Might be worth digging up one of those threads and sending a PM. That said, my money is on you being disappointed to learn it's not certified as a primary ASI or altimeter.
 
WDD said:
For some reason I thought if you had an electronic ADI you need a second one as well (electronic or vacuum). But you don't need a back up if you have a vacuum driver ADI - which given the reliability of the two makes no sense to me.
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That's true for IFR. VFR is a bit different.
 
asicer said:
That's true for IFR. VFR is a bit different.
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Sort of. There's a distinction between an "EFIS" under the regs and an "attitude indicator" that happens to have a digital presentation (like the G5, for example). An EFIS, like an Aspen or a G3X, requires backup instruments for IFR. The G5 does not (in other words, the G5 does not require that you have a backup attitude indicator, which is what the G5 legally replaces).
 
Clip4 said:
what VFR aircraft do you know of with only an electronic altitude display? Even on aircraft with the G5 the old analogue altimeter is primary altimeter.
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The G5's airspeed and altitude tapes were never certified as primary. The GI 275's were.

bradg33 said:
If you have an account on Beechtalk, there are a few threads discussing the install manual and a few folks expressed a willingness to privately provide a copy. Might be worth digging up one of those threads and sending a PM. That said, my money is on you being disappointed to learn it's not certified as a primary ASI or altimeter.
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Incorrect - The G5's altimeter and airspeed indicator were not certified as primary, but the GI 275's were. I do have a copy of the installation manual.

Standby attitude, altitude, and airspeed are not required for VFR only aircraft even with a single GI 275 Primary ADI. Section 3.2.2 Standby Instruments says flat-out "Standby instruments are not required for aircraft limited to VFR-only operations."

Magnetic compass, however, is always required, per the last sentence of section 2.1.1 System Installation Limitations: "The aircraft’s magnetic compass must be retained for all GI 275 installations."

For IFR aircraft, there is some additional backup required. You get three options:

1) A second GI 275 or other glass and a Display Backup switch (which forces the second one to show the primary AI page)
2) Backup analog attitude, airspeed, and altimeter
3) Backup airspeed, altimeter, gyro-stabilized heading (ie DG/HSI), and turn coordinator.

Hope that helps.
 
flyingcheesehead said:
The G5's altimeter and airspeed indicator were not certified as primary, but the GI 275's were. I do have a copy of the installation manual.

Standby attitude, altitude, and airspeed are not required for VFR only aircraft even with a single GI 275 Primary ADI. Section 3.2.2 Standby Instruments says flat-out "Standby instruments are not required for aircraft limited to VFR-only operations."

Magnetic compass, however, is always required, per the last sentence of section 2.1.1 System Installation Limitations: "The aircraft’s magnetic compass must be retained for all GI 275 installations."

For IFR aircraft, there is some additional backup required. You get three options:

1) A second GI 275 or other glass and a Display Backup switch (which forces the second one to show the primary AI page)
2) Backup analog attitude, airspeed, and altimeter
3) Backup airspeed, altimeter, gyro-stabilized heading (ie DG/HSI), and turn coordinator.

Hope that helps.
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That's wild—thanks for sharing. So with dual GI 275s and a backup switch, you could pull the airspeed indicator and altimeter out of your panel and still be legal for flying IFR. Could you pull the VSI as well?

Not that I have any intention of doing so. I like my analogue steam gauges — I work all day on a computer screen, so I don't want to fly one.
 
wasnt Sarasota avionics or someone like selling a VSI version of GI-275 ? i havent seen one on Garmin site though
 
David Megginson said:
That's wild—thanks for sharing. So with dual GI 275s and a backup switch, you could pull the airspeed indicator and altimeter out of your panel and still be legal for flying IFR. Could you pull the VSI as well?
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Yup. I think one of Garmin's airplanes was done this way just to show what you could do if taken to the extreme:

Before:
Screen Shot 2021-05-28 at 5.04.39 PM.png

After:
Screen Shot 2021-05-28 at 5.04.56 PM.png

Of course, that's also a convenient way to show off the four main purposes for a GI 275: ADI (front and center), HSI (bottom), MFD (right), and EIS (left). And the amount of information packed into them is crazy.

WannFly said:
wasnt Sarasota avionics or someone like selling a VSI version of GI-275 ? i havent seen one on Garmin site though
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This one? It's been in development for kind of a long time, and if Spruce's web site is to be believed, still no STC. Never seen one in the wild either: https://www.aircraftspruce.com/pages/in/vsi_aerospace/aerospacelogic10-06272.php
 
WannFly said:
This is the one I was talking about https://sarasotaavionics.com/gi-275-ivsi
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Wow! That's new. Neither my Install Manual nor my Rev A Pilot's Guide mention that version. It is in the Rev E Pilot's Guide, so it appeared in there somewhere. In fact, the revision record says the IVSI appeared in Rev C in December 2020, so it's pretty new!

It sounds like it might require TCAS though, which is generally quite expensive.
 
flyingcheesehead said:
Wow! That's new. Neither my Install Manual nor my Rev A Pilot's Guide mention that version. It is in the Rev E Pilot's Guide, so it appeared in there somewhere. In fact, the revision record says the IVSI appeared in Rev C in December 2020, so it's pretty new!

It sounds like it might require TCAS though, which is generally quite expensive.
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You won't be seeing this unit in any light piston airplanes... it's not what you think it is.

"The GI 275 IVSI offers a new alternative to display TCAS II information (including Resolution Advisories) from either Garmin GTS 8000 or (ARINC 429 based) 3rd party TCAS II systems."
 
Ryan F. said:
You won't be seeing this unit in any light piston airplanes... it's not what you think it is.

"The GI 275 IVSI offers a new alternative to display TCAS II information (including Resolution Advisories) from either Garmin GTS 8000 or (ARINC 429 based) 3rd party TCAS II systems."
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Because my install manual is from before this version existed, I'm not sure whether TCAS is required or if you could just put it in as a pure IVSI without using the traffic features.
 
flyingcheesehead said:
Because my install manual is from before this version existed, I'm not sure whether TCAS is required or if you could just put it in as a pure IVSI without using the traffic features.
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The PFD version has a VSI built in, so a stand alone VSI 275 is redundant
 
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