db8

Well Known Member
Don't know if this should be placed under the "GPS" section or this "general."

First off, I was a military guy and now a commercial pilot, so I don't know the ins and outs of the small GPSs (yet). I am building an 8 and will be installing the dual GRT Horizon HS EFIS displays (two) with the internal GPS. I don't plan on doing a whole bunch of IFR flying, but want the "legal" capability to do it when I'm cross country and need to. That being said, since I am flying mostly VFR, I don't think I need to get some big expensive GPS like the 430 or 530 or whatever. From what I understand, the data is in the GPS and can be retrieved with the GTR. Unless I'm looking at this wrong, why not just get a used Apollo GX 60 or something similar and save $5000 or so? Does anybody have any good knowledge on this. I know a lot is opinion, but I'm all ears. Are there several GPSs that might fit what I'm looking for (ie manufacturer and model # -- preferably from someone who has the worked with the GRT and the certified less expensive GPS they are recommending)? I would prefer a com with it too. Thanks for any input. Dave:
 
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Although the GX60 would give you IFR enroute and non-precision approaches, you would not have ILS approach capability. Without ILS, it becomes important to have GPS/WAAS to get to the lower altitudes which often exist, either planned or unplanned. I have the Garmin SL-30 NAV/COMM which serves as two radios since both the COMM and NAV can monitor the standby frequencies. Granted that this does not have hardware redundancy of two radios, but radios are extremely reliable and if COMM fails, there are the fallback flight rules and if the NAV radio fails, there is the missed approach and rerouting via GPS. For the IFR GPS, I have the Garmin 155XL (GPS only). Both the SL-30 NAV (for ILS) and the 155XL GPS are coupled to the Mid-Continent MD200-306 Course Deviation Indicator (external CDI is required, by regulation) thru the AK950 enunciator/switch. All this adds up to about $6000 plus the CDI which is another $1,400. There are some cheaper CDI's but the MD200-306 allows all features of the SL-30 to be utilized. Whatever you choose; legal, safety, and potential equipment failures need to be considered.
 
Forgot to add

Forgot to add that I will be getting the Garmin SL-30 com/nav also to have ILS through the EFIS.
 
Internals for VFR, approved externals for IFR

As I understand the rules, the GPS systems offered internally to experimental EFIS systems should be used for VFR only. I have not looked at the Chelton's so they may be an exception.

I know GRT has a GPS WAAS with RAIM advertised for the near future, but there is no mention of the database. For IFR legalities, this GPS would have to be demonstrated by the builder to meet the relevant TSO and be equiped with an approved database.

If you are planning to fly IFR, I would go with the plan you mentioned, an approved external GPS and not bother buying the internal GPS's unless you want them as an emergency backup.
 
IFR GPS

I would recommed getting a Garmin GNC300XL GPS/COMM if you want the lowest cost IFR GPS capability. This would also give you a backup Comm as well.
 
solution

Sounds like I'll end up going with the Garmin GNC 300XL, SL-30 and no internal GPS. Thanks for the inputs. Dave
 
What's the cost delta of going with a GNS-430 and deleting the SL30 or substituting a SL40 or other low cost comm if you want a 2nd comm? This would give you the NAV receiver in the 430 rather then in the SL30.

I would bet there are some good deals on the older non-WAAS 430's.
 
Options

That is another option. I can get a refurbed GNC 300xl w/warrany for under $3000 and the SL-30 for just over $3000. That gives me two coms, one nav and one IFR certified GPS. Anybody have a 430 non-wass they want to let go at a good price (and extra radio)? Am in no hurry. Let me know if you do. Thanks. Dave