note: the kc140 is a rate based AP and does not have that expensive KI256
There is an STC for the DA40 to upgrade to WAAS for DA40’s manufactured in Canada. but I don’t know if its only FAA approved
and for the same price you can install a G500 (in a cheaper DA40 with analog instruments)
lenthamen wrote:
Should we go for the DA40 with G1000 or go for the G500 retrofit option?
The G1000 is very intergrated, which makes it impossible to beat on that point on the long run. The downside is that software approval by Diamond can take quite long, so you won’t have the latest features. The G1000 is upgradeable, but these upgrades are always quite expensive and is often major / STC in which the airframe manufacturer also takes part. What will hapen over lets say 10 year, when some new features are available, will they be available on older units as well. If you can’t have the upgrades, but newer aircraft can the price will drop. You see this a lot on manufacturers which produce a new generation every few years. Basically this allready happens with the non WAAS and WAAS G1000 variants. New equipment, or equipment from other manufacturers might be hard to intergrate, or to control that equipment. You will be depend on Garmin to make such software available, and Diamond to approve this as well. There is little space for additional equipment on the panel.
The G500 or Aspen will give you more possibilities to stay up to date with your aircraft on the long run. You can also interface, especially with Aspen with equipment from other manufacturers, which makes you less depended on Garmin. The lesser intergration makes that you don’t have anything to do with Diamond as well.
I think Walter’s comparison with IOS makes sense.
Peter wrote:
Any GPS can drive a KAP140 without the GAD43.
While that is true, it then is not controlled by the G500 but directly by the GPS. This is not wanted in most cases.
wigglyamp wrote:
How many non-WAAS DA40 aircraft are out there as potential candidates for a WAAS upgrade if a third-party STC was available?
I think the G1000 WAAS is what you are refering to. There is a third party STC for this, though expensive, unfortunatly don’t got details.
Peter wrote:
Some people fit a roll steering converter (e.g. a GDC31) to get more precise steering from the GPS. But it isn’t really necessary; the NAV mode of the AP still works well enough.
GPSS is quite usefull and makes quite a difference with NAV mode. In NAV mode the autopilot acts as tracker, it makes slow movement, with GPSS your autopilot flies the magneta line with standard rate turns, just as you turn the autopilot manually in HDG mode with the HDG bug.
Though some like to have more manual control, and turn the HDG bug themselfs, for situational awareness and to have a good understanding what it is doing.
Jesse wrote:
I think the G1000 WAAS is what you are refering to. There is a third party STC for this, though expensive, unfortunatly don’t got details.
OK – if there’s already a third party STC available for the G1000 non-WAAS to WAAS upgrade, then there’s no point in me considering writing another one.
If the existing one costs €28k (posted above) then you could undercut that completely outrageous price and a lot of people would benefit 
No way. Two GIA63Ws will set you back a cool 18k USD and that is only for the hardware. Enroute Vnav is another cool 10k. And if you still need an autopilot that has been certified to work with the waas input…
Good luck with getting a Chinese Da40 STC for a waas upgrade certified in EASA land with companies like garmin and diamond involved…
I guess pianos learn to fly before that thing gonna take off…
To come back to the original question, a personal point of view: for anything with such a long life as an aircraft, I would take modular upgradeable avionics (g500+gtn) over non modular any day.
In 15 years time the plane will still fly fine, the G1000 will look completely outdated, but a g500 can potentially by replaced by the flavour du jour avionics.
An additional point is that Garmin, like all companies, will someday stop innovating and will make the vast majority of their money milking the installed base. When that happens, you don’t want to be the guy locked in with them. It might take 10, 20 years, but again those planes you’re buying today could still be flying then.
An extremely good point above.
Even the G500 is sort of borderline when it comes to flexibility because only a Garmin dealer has the codes to configure the various bits of it, though you may be able to get them via contacts in low places.
Peter wrote:
Even the G500 is sort of borderline when it comes to flexibility because only a Garmin dealer has the codes to configure the various bits of it, though you may be able to get them via contacts in low places.
I would say the major difference is that Garmin was always interested in selling G1000 pretty much only to OEMs (there are exceptions, but it’s tightly controlled; I think it got a little better with G950) while there are plenty of “outfits” that can install a G500 (and therefore can upgrade it). G1000 supports third party hardware, it should be quite similar to G500. One difference being GPS where G500 needs an external unit while G1000 doesn’t. Another is transponder. And G500 offers no integration with the airframe/ powerplant (actually, there appears to be a possibility of connecting it to Meggitt engine instruments, not covered under Garmin STC) while G1000 does which makes it tied to the airframe and creates the second big issue.
Problem really being that certification is expensive. I.e. tearing out an integrated system and replacing it is just not an option. It’s an issue even on jets. And even gradual upgrades have the potential of being a major PITA in terms of certification because of the integration. Really, upgrading nav/ com unit of a G1000 shouldn’t be any more difficult that doing the same with G500 – it should be like replacing 430 with 430W.
