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G5 as a replacement for gyro AI

PostPosted:Wed Feb 19, 2020 1:04 pm
by Lerk
My share-o-plane has a poorly AI.

Having used a twin G5 setup in another aeroplane I think that’s an awesome upgrade proposal, but I’m conscious of the cost of installing the second, dearer, HSI capable G5 that is not strictly necessary at this point in time.

I know you can install a single G5 but what do you actually get on the screen with a single AI unit?

We already have a GTN650 which is connected to a Garmin CDI, can this be added to the heading ribbon on the g5?

Re: G5 as a replacement for gyro AI

PostPosted:Wed Feb 19, 2020 1:42 pm
by GrahamB
You can certainly interface a G5 with a single GTN box as a replacement for an existing AI.

You need the GMU11 magnetometer if you want it to display Heading on the top strip though, otherwise it will just display Track.

Re: G5 as a replacement for gyro AI

PostPosted:Wed Feb 19, 2020 2:45 pm
by Lerk
So you still get the speed tape (airspeed or ground?) and the altimeter tape (with alt. bug)?

Will the FPL track appear on the heading display too?

Re: G5 as a replacement for gyro AI

PostPosted:Wed Feb 19, 2020 3:01 pm
by GrahamB
The device is connected to the pitot-static system, so you'll get IAS in the LH tape and barometric altitude in the RH tape, as well as a VSI indication. The pressure setting is adjusted with the knob as per a conventional altimeter, and the menu allows you to set an altitude bug.

TBH I'm not sure what Nav data you'll get displayed from the GTN.

On a dual AI/HSI fit you get CDI and Glideslope indications, along with pips on the heading tape for course and current track. I believe that's the case with a single AI fit but I'm not 100% (I have a dual fit).

The latest software will also display TAS and wind vector if you also add the Garmin OAT probe.

Re: G5 as a replacement for gyro AI

PostPosted:Wed Feb 19, 2020 3:06 pm
by Lerk
Not quite as basic as you'd first think then!

For some reason I had in mind that the majority of the extra features came from the second unit...

Re: G5 as a replacement for gyro AI

PostPosted:Wed Feb 19, 2020 9:32 pm
by Duncan M
I thought G5s were the same. Could be configured to either AI or HSI display.
2 are used to see both displays at same time and as backup in case of single G5 failure.

Re: G5 as a replacement for gyro AI

PostPosted:Wed Feb 19, 2020 10:53 pm
by riverrock
There are 2 G5 units - the certified one and non-certified one. The non-certified version is a bit more flexible (can use an internal GPS source). The rest is config - you can hide any indications you don't want on the screen (or don't plumb in) and you can switch between HSI and AI views (useful for regression in a twin unit system).
The AI view can show flight director chevrons, course deviation and glide slope along with lots of other data.
Image

Re: G5 as a replacement for gyro AI

PostPosted:Thu Feb 20, 2020 7:04 am
by Lerk
The Hsi unit is a different more expensive box too... hence my confusion!

Re: G5 as a replacement for gyro AI

PostPosted:Thu Feb 20, 2020 7:15 am
by Duncan M
Lerk wrote:The Hsi unit is a different more expensive box too... hence my confusion!


Lerk, I think you are misinformed on that.
See riverrocks post above.

Re: G5 as a replacement for gyro AI

PostPosted:Thu Feb 20, 2020 7:34 am
by Lerk
I’ve just worked out why I thought that...
Got an estimate on the twin upgrade and they’d grouped additional components into the price of the G5’s depending on which function they were being used for...

Re: G5 as a replacement for gyro AI

PostPosted:Thu Feb 20, 2020 8:57 am
by GrahamB
I meant to mention, you also get the Turn and Slip function on the AI. You can see the balance ball clearly in the image posted above, but not as obvious below it is the slip indicator.

However, you can’t replace both instruments with a G5 AI in a certified installation - you can use it to replace the AI, or the TI/TC, but not both.

As regards the Flight Director bars they do not appear as standard, obviously. They will only be enabled if the unit is interfaced to an FD capable autopilot, and FD or AP mode active.

I’ve also just remembered. With the OAT probe fitted, only TAS is displayed on the AI unit; you need the HSI to see wind vector.

Re: G5 as a replacement for gyro AI

PostPosted:Fri Feb 21, 2020 6:40 pm
by Rallye
One comment.I have a G 5 on my airplane and the sight of artificial horizon and the altitude and airspeed are ok,but the sight of the vertical speed indicator is really bad.
As far as i know it is agreed for the artificial horizon,but not for the other infos.

Re: G5 as a replacement for gyro AI

PostPosted:Fri Feb 21, 2020 10:33 pm
by Peter Kelly
If anyone actually cares, the certified and uncertified versions of the G5 are physically identical items with the same part number.

The difference is in the box part number. The box for the certified G5 has the STC paperwork inside and the uncertified one doesn't.

The install manual (different for the certified and uncertified versions) specifies how the G5 is to be set up. In the opening note about Scope, the Part 23 AML STC Installation Manual states, "Only the interfaces between the Garmin G5 Electronic Flight Instrument and equipment listed in this manual are approved by the STC." Make of that what you will.

Re: G5 as a replacement for gyro AI

PostPosted:Sat Feb 22, 2020 9:05 am
by Bathman
Looking at prices on Harry Mendelssohn

£1194.00 for the uncertified unit and £2130.00 for the certified unit. Which by all accounts are the same.

If the GA sector is to flurish in the UK then this price difference needs change. How and earth can the price of paperwork for certification nigh on double the value of the instrument.

Re: G5 as a replacement for gyro AI

PostPosted:Sat Feb 22, 2020 9:47 am
by GrahamB
Thus it ever was. I wouldn’t single out Garmin, and looking at it another way, the uncertified units they sell will have helped lower the costs of the certified ones.

If we don’t pay for certification, we don’t get parts for our certified aircraft, and the fleet is grounded.

A $30 fuel pump for a 1970’s Ford truck becomes $250 with certification. It’s not just the shiny things which attract the certification premium.