G5 or GI275 + Century 2b

[Martin S.]

Hello everybody,

does anybody know whether I can drive my Century IIb with either the G5 or the GI275 and then dump anything related to the old vacuum system?

Background is that I have a leaking vacuum o-ring. Replacing it requires removing the accessory case. That‘s quite a big effort for only one ring. Then rather going G5 directly and dumping it.

Thanks,

Martin

 

 

[N201MKTurbo]

I don’t remember any o rings on the vacuum pump drive shaft. There is an oil seal on the outside. I didn’t install it because I have a scavenger pump installed there. It seems like you could change that oil seal without removing the accessory case.

[LANCECASPER]

1 hour ago, Martin S. said:

Hello everybody,

does anybody know whether I can drive my Century IIb with either the G5 or the GI275 and then dump anything related to the old vacuum system?

Background is that I have a leaking vacuum o-ring. Replacing it requires removing the accessory case. That‘s quite a big effort for only one ring. Then rather going G5 directly and dumping it.

Thanks,

Martin

 

 

You can't drive it with the G-5, but you can with the GI-275

https://static.garmin.com/pumac/gi275_autopilot_compatibility_c.pdf

[bradp]

Lance is correct. You need to retain the vacuum driven attitude indicator with a IIb and the G5. 

[OR75]

G5 as an HSI and GI275 to provide attitude ? 
the GI275 can do both I believe but that’s too much in one indicator imho 

[RobertGary1]

2 hours ago, OR75 said:

G5 as an HSI and GI275 to provide attitude ? 
the GI275 can do both I believe but that’s too much in one indicator imho 

and the GI-275 is a much better HSI than the G5.

[David Lloyd]

2 hours ago, OR75 said:

G5 as an HSI and GI275 to provide attitude ? 
the GI275 can do both I believe but that’s too much in one indicator imho 

Yes, the GI275 will do both, but life and avionics are complicated.  The GI275 comes in 4 main flavors: AI, HSI, MFD and EIS.  If you are replacing an AI in your 6 pack with a GI275, it must be purchased and will function as an AI.  A pretty fancy one, it will show true airspeed and standard rate turns if the temp probe is installed, it will show traffic alerts (from a Garmin source), some neat stuff if synthetic vision is purchased.  If installed as an AI, it will not show any other displays such as the traffic page, maps, safe taxi, etc.  If you are replacing a DG or HSI in your 6 pack with a GI275, it must be purchased and will function as an HSI. A pretty fancy one, it will selectively display background maps, different nav sources, bearing pointers, waypoint info, heading bugs, etc.  It will work with your autopilot. Read the Pilot Guide, about 200 pages are devoted to all the stuff the HSI will do.  It will not show any other displays such the traffic page....  If installed in you panel as a pair, AI/HSI, the HSI will also work as a backup AI (unless something really weird happens like in another thread).  The EIS will function only as an EIS.  The MFD will display all the pretty stuff pictured on the Garmin website. If the AI and HSI are installed as a primary pair, the MFD will display and be a backup as long as the optional AHRS is purchased.  

Not all this is revealed on the Garmin website, some is in the Pilot Guide.  Some is answered at the radio shop or other forums.  Right now Garmin has a bundle pricing deal on the AI/HSI combo and synthetic vision until sometime in June.

Leaking vacuum o-ring?  Remove accessory case?  Don't think you got that correct.  

[dooleypster]

I have a Century 2000 autopilot, and had to go with the G275 over the G5 due to the legacy autpilot. I decided to go with 2 G275s and remove the entire vacuum system.  I have a J model, so no air powered step...... therefor the vacuum system (including the standby vacuum pump) can be removed completely.  David is right on with his comments about compatibility.  The G275s come in a variety of flavors depending on what you want them to do.  Synthetic vision aside, a really good system will do just about everything including redundancy for the AI and work with legacy autopilots.  Seems like the installed price for the dual G275 system (sans synthetic vision) was around 10 AMUs.  I still have the pitot and static powered instruments as well.  I like the setup....... but its not cheap.  Be sure you get the right add-ons to do what you want the system to do.

[OR75]

My preferred option would be to have a G5 to replace the DG/Indictor ( so effectively a G5 used as an HSI) and provide GPSS

and a GI275 to provide attitude information 

[jetdriven]

3 hours ago, dooleypster said:

I have a Century 2000 autopilot, and had to go with the G275 over the G5 due to the legacy autpilot. I decided to go with 2 G275s and remove the entire vacuum system.  I have a J model, so no air powered step...... therefor the vacuum system (including the standby vacuum pump) can be removed completely.  David is right on with his comments about compatibility.  The G275s come in a variety of flavors depending on what you want them to do.  Synthetic vision aside, a really good system will do just about everything including redundancy for the AI and work with legacy autopilots.  Seems like the installed price for the dual G275 system (sans synthetic vision) was around 10 AMUs.  I still have the pitot and static powered instruments as well.  I like the setup....... but its not cheap.  Be sure you get the right add-ons to do what you want the system to do.

You must’ve got the deal of the century because the hardware is about 10 grand, in fact 2 G5’s cost about 10,500 installed...275s are more like 14k.  

[jetdriven]

3 hours ago, OR75 said:

My preferred option would be to have a G5 to replace the DG/Indictor ( so effectively a G5 used as an HSI) and provide GPSS

and a GI275 to provide attitude information 

The issue there is neither unit is a reversionary backup for the other. 

[OR75]

13 hours ago, jetdriven said:

The issue there is neither unit is a reversionary backup for the other. 

Ok ... i guess I need to elaborate ...  i replaced my TC with a G5 and my DG/GI106 with a second G5 ... they back each other 

I am waiting for the Vacuum AI to go belly up to look at the option of replacing it with. GI275. 
I chose not to install the AI G5 on top of the HSI G5 because I did not want to oval the top 3 1/8 hole 

I am surprised by the cost you have for 2 G5s installed 

Edited May 26, 2021 by OR75

[jetdriven]

A G.I275 and a g5 are not reversionary for each other.  Which is why you have to pick a pair of one or the other. 
2 G5’s plus he hardware to install it is over $7000. And it takes labor to install that stuff. They say 25-30 hours but it seems to take more. I’ve  only installed two GI275s, but the AHRS version 4400 bucks, and AHRS+AP is 5k.  So ten grand in hardware again, plus another good bit for materials, plus labor.  The going rate around here for a pair of those is about 14 grand. 

I thought the STC for the G5 requires it to be installed in the pilot center position if used for primary attitude, and for backing it up it has to be primary. But I could be wrong.

Edited May 26, 2021 by jetdriven

[OR75]

56 minutes ago, jetdriven said:

A G.I275 and a g5 are not reversionary for each other.  Which is why you have to pick a pair of one or the other. 
2 G5’s plus he hardware to install it is over $7000. And it takes labor to install that stuff. They say 25-30 hours but it seems to take more. I’ve  only installed two GI275s, but the AHRS version 4400 bucks, and AHRS+AP is 5k.  So ten grand in hardware again, plus another good bit for materials, plus labor.  The going rate around here for a pair of those is about 14 grand. 

I thought the STC for the G5 requires it to be installed in the pilot center position if used for primary attitude, and for backing it up it has to be primary. But I could be wrong.

the 2 G5 stack is 5500+tax (the second does not require the GMU and the GAD. Add $250 if you want the OAT (which is great for winds aloft and density altitude) 

The vacuum AI is still primary. 

Why couldn't you have: GI275 (AI) and 2 G5s (HSI/TC) ?  or a GI275 (AI), a G5 (HSI) and the electric TC (not talking aesthetic)  

 

[jetdriven]

Id love to know where your buying.  The 2G5s plus the GAD29B, GMU11, and the GTP59+GAD13 is 6600 plus shipping. There’s another $200 worth of wire, circuit breakers, Pitot static tubing, ring terminals, solder sleeves. And someone has to install it. It isn’t free.  So, if you have an invoice  less than 10k for two G5’s installed, I’d love to see it. And I can’t see 275s installed for that since two boxes with the two units alone are around  that. 

[OR75]

The GTP 59 would add $300 but honestly the other OAT probe works just fine 

[jetdriven]

Thank you for the link, that’s like 900 bucks cheaper than aircraft Spruce 

[Martin S.]

Thanks for your comments everybody. I went back to the IPC and it really looks as if I misunderstood something. I'll have to go back to the plane and compare things to the IPC and re-check the whole thing. Will keep you guys in the loop.

 

Greets,

 

Martin 

[OR75]

On 5/26/2021 at 4:06 PM, jetdriven said:

A G.I275 and a g5 are not reversionary for each other.  Which is why you have to pick a pair of one or the other. 
2 G5’s plus he hardware to install it is over $7000. And it takes labor to install that stuff. They say 25-30 hours but it seems to take more. I’ve  only installed two GI275s, but the AHRS version 4400 bucks, and AHRS+AP is 5k.  So ten grand in hardware again, plus another good bit for materials, plus labor.  The going rate around here for a pair of those is about 14 grand. 

I thought the STC for the G5 requires it to be installed in the pilot center position if used for primary attitude, and for backing it up it has to be primary. But I could be wrong.

I think I understand what goes on: the GI275 requires a backup AI or a TC ( see the install limitations part) a second GI275 plays that role because it is reversionary. A G5 is not. But if a G5 is installed as an AI (and not an HSI) then you have your backup . 

[jetdriven]

Yes, but the G5 attitude indicator is not primary for the century auto pilot attitude.

[OR75]

11 minutes ago, jetdriven said:

Yes, but the G5 attitude indicator is not primary for the century auto pilot attitude.

No it is not. You need at least 1 GI275. 

and if you want to get rid of the vacuum system , you need to add: 

a 2nd GI275

or a TC and a G5 (HSI)

or 2 G5s (AI / HSI)