A non-WAAS gps will do you no good as of 1/1/2020 when ADSB is required in the NAS. No way should you spend money on a gps that is non-waas today when it will be require replacing or another big$ upgrade in less than 3 years.

NineThreeKilo wrote:
Per the WAAS thing, it's a great thing to have, I'd want a WAAS box if I was buying, but to say a non WAAS GNS isn't very useful isn't accurate, you still can shoot all the normal VOR and ILS stuff, RNAVs, just can't shoot the LPVs and the like, where I live we have more non WAAS RNAVs than LPVs, that said WAAS also gives you a "complementary glide slope" on some non LPVs, it's not a LPV but helps to take out the step down, level out, step down, level out bit.

Not sure by what you mean by "A non-WAAS gps will do you no good as of 1/1/2020 when ADSB is required in the NAS. No way should you spend money on a gps that is non-waas today when it will be require replacing or another big$ upgrade in less than 3 years.

Don't the new xponders that are ADSB out have WAAS gps built in? I thought your GPS navigation only needed to be WAAS for LPV type approaches.

Tom

Ive only noticed one or two models that have an in-built GPS, like the Stratus transponder does. The rest required a serial connection to an external source.

Ya, the stratus Xponder is reasonably priced at $3000 with built in WAAS GPS.

Some do, but most do not. If it does, then they are $2-3k more than the models that do not. f you buy a non-waas garmin 430, you will still need to buy a waas gps source from somewhere. And the cheapest option is a trig TN70 ($1900 made by NextNav)- which adds another receiver antenna to the top of your plane.

waas is not required for navigation - it's required for ads-b. That's why it makes no sense to buy a non-waas 430 unless the price reflects it, and it's upgradeable by garmin to WAAS (I heard that's 4k from garmin if they even support them any more).

a3holerman wrote:Not sure by what you mean by "A non-WAAS gps will do you no good as of 1/1/2020 when ADSB is required in the NAS. No way should you spend money on a gps that is non-waas today when it will be require replacing or another big$ upgrade in less than 3 years.

Don't the new xponders that are ADSB out have WAAS gps built in? I thought your GPS navigation only needed to be WAAS for LPV type approaches.

Tom

DeltaRomeo wrote:As mentioned previously, I have no desire to be in the soup. In my case, most of this necessity is caused from a simple cloud layer that precludes a VFR departure. Where I live is on the edge of moisture streams that develop in the Pacific, traverse Mexico and Texas and proceed to the eastern half of the US. Once clear of that moisture stream (usually about 100 miles), its VFR the rest of the way west.

Another issue I'm trying to cypher is if some of the ADSB equipage may dovetail with IFR. The WAAS feature seems to be one aspect that will. Determining which equipment that will provide WAAS that will work for IFR approaches and be useful for ADSB as well is a puzzle.

The requirement for ADS-B Out is to provide an "approved position source". I don't know about other equipment that will do the trick, but the 430W will. That, coupled with a KT74 transponder, which by itself is an ES transponder and a $2500 box, is how my airplane complies with the ADS-B Out requirement that will be effective in 2020. Of course, there are all-in-one transponders that have the "approved position source" built in, such as the Garmin GTX 345, a $5000 box, or the Lynx NGT 9000, a $5400 box (plus installation, of course).

Starting from scratch with a blank panel would be a real chore, to decide what equipment would be desirable. For a light GA airplane, non-FIKI, that is only used for relatively benign IFR, you sure don't need a $100,000 panel, and obviously you'll get an enormous amount of differing advice, based on each individual's personal tastes. There are those who won't dare bust a cloud without dual 750s (big screen version of a 650), a full 3 axis autopilot, the latest and greatest many function transponder, and all glass screens instead of round gauges. There are others who are willing to fly pretty consistent IFR with the bare minimum of a single 720 channel navcom, and an old Narco 150 transponder. I suggest that if money is an object like it is for most people, somewhere in between those extremes is a good target. You probably want something serviceable, but not overly elaborate.

If I had my druthers (and an extra $20K sitting around), I might like to have a simple single axis autopilot added to my airplane, which would be nice when I want to look at a chart, or prepare for an approach, or do something else that takes me away from scanning for a moment. Otherwise, what I have is completely adequate for me, for the kind of IFR flying I do in my relatively simple airplane. I'm not overwhelmed by having a whole lot of stuff I don't need, but I have everything I do need to safely conduct any IFR flight that my airplane can handle.

Cary

KISS applies to instrument as well as contact flying. Some radios, instruments, and devices make flying simpler while some increase the pilot workload. Requiring GPS coordinates for for pipeline spot reports, with most GPS equipment, makes them difficult and dangerous. FAA requirements for flying IFR in the clouds, however, are simple and logical.

One advantage of going 430/530 waas over non-waas is that Garmin seems to be supporting the W version more actively than the non-w.

A few years ago I upgraded my 530 to waas mainly to have the position source for my then-new gdl88 adsb. I've since added the garmin flight stream to connect to foreflight, which is pretty slick.

Back to your original question, I put a second radio in my Husky mainly to listen to awos or ctaf before I get to my destination while still with flight following.

What kind of ifr flying are you going to do? I stay current so that I can pop through the central Texas morning scud. Other than that I'm not all that intersted in single pilot ifr in a plane with no autopilot. I'd scale your upgrades based on your practical ifr flying plans.

Adding to my comments earlier, regarding WAAS for approaches. There are non-WAAS GPSs which can shoot non-precision GPS approaches, but having the WAAS capability means that you can shoot precision GPS approaches as well--and that's just exactly like flying an ILS.

Not certain where you are in your IFR training, but let's look at a quick recap of approaches. There are essentially 2 categories, precision and non-precision.
A precision approach is one that gives both lateral/horizontal guidance and vertical guidance. At the end of the approach, the lowest the airplane can be descended to is called a decision height or decision altitude. If the runway environment isn't visible at that point, the pilot must go around.
A non-precision approach provides lateral guidance but only designated altitudes, and the pilot has to refer to the altimeter to fly the airplane at those altitudes. Instead of a DH/DA, the lowest the pilot can go is called a minimum descent altitude, MDA. But the go around point is determined not by that altitude, but instead by timing from the final approach fix. Those times at different ground speeds are printed on the approach plates of non-precision approaches.

Without using GPS, within those 2 categories, the only precision approach is an ILS, which provides both lateral guidance and vertical guidance.

Without GPS, non-precision approaches include LOC (localizer only), VOR, and NDB (ADF) approaches.

Using GPS, within those 2 categories, the only precision approach is an LPV (localizer performance with vertical guidance). For practical purposes, this works just like an ILS. There is also LNAV/VNAV (Lateral/vertical navigation), which is very similar, but it's not as accurate as an LPV because the "beam" doesn't narrow as the airplane approaches the runway. While both of these approaches will have both vertical and horizontal guidance, the LNAV/VNAV approach will have higher minimums due to that lesser accuracy, but both have a DA/DH. Because of that lesser accuracy, it's not considered a precision approach, but it is flown the same way. Both of these approaches require a WAAS receiver.

Using GPS, the remaining non-precision approaches are LNAV (Lateral navigation), LP (Localizer performance--more accurate laterally than the LNAV), and one that's just called GPS, which is just like an LNAV. None of these approaches provide vertical guidance, and all of them have an MDA. None of these require a WAAS receiver, but the receiver must nonetheless be approved for approaches (some GPS receivers are approved only for enroute IFR use).

You may be wondering why so many types of GPS approaches, and the best answer is that the GPS system started simply--no approaches, and only enroute guidance. Then simple GPS approaches were created overlaid upon existing VOR and NDB approaches. Then as technology improved and became more trustworthy, GPS only approaches were created, and soon that morphed gradually into the more precision approaches aided by WAAS. Here's a pretty neat summary article: http://www.aviationsafetymagazine.com/i ... 164-1.html

The bottom line of this is that if you want to take advantage of the best that the GPS system has to offer, you need a WAAS receiver. So far as I know, the least expensive way of doing that is with a 430W. Although they're no longer made, Garmin promises that they'll be supported into the foreseeable future. There are used ones available. There are also used non-WAAS 430 receivers available, which Garmin will modify to be a 430W, for something like $2800, and although they're completely rehabbed in the process, their processor is a little slower than the 430W as factory made.

More information than you probably wanted to know. Sorry about that!

Cary

Thanks, Cary; not too much info at all and everything I've been trying to find answers to.

In this day of digital library, the info is out there. The challenge is wording the query so that the search engines can return meaningful results. If you don't know what you don't know, getting usable answers is a needle in a haystack chance. Which is why having forums like this are so great. One should try to resolve their questions searching as best they can so as not to be burdensome and repetitive but sometimes you just have to ask someone.

A couple of really good places to get a lot more detail on all this is the FAA's pubs, Instrument Flying Handbook and Instrument Procedures Handbook. They're a bit boring, but it's all there. You can download them for free from FAA.gov.

Cary

The cost of a WAAS enabled xponder with ADSB out is VERY close to the cost of non WAAS ADSB xponsers and as time goes by the price will come down even more.
The bottom line is that a 430 Non WAAS will limit you to non precision "like" approaches whereas the WAAS version will enable you to shoot precision like approaches. The cost of upgrading is an absurd $3000 so its a no brainier which one to buy.
Keep in mind with the new part 23, I think it is, rewrite it will allow many of the now certified GPS units to get certification guickly and I believe in the next two years we ill see a dramatic reduction on cost.
Tom