WAAS GPS for IFR Approaches

[boom3]

Originally Posted by N804RV

Here's my take on this: Frequently, I'm stuck waiting for a marine layer to burn off. I only plan to file IFR to get out. I'd prefer to launch knowing I'm heading into VFR at my destination. I'm just not brave enough to fly to a destination that is likely to be IFR on my arrival.

It seems to me an non-WAAS GNS 430 is still gonna have a lot of life left in it for the foreseeable future. And, non-precision RNAV approaches are perfectly fine for the kinda flying I plan on doing. I have a KX-155/GS, KI-209, and MKR BCN that will be kept separate from my EFIS and GPS. And I'll use Skyview stuff for ADS-B out compliance.

Wondering what other builders' thoughts are.

Hi Ken,

Here's my opinion. I have an "outdated" glass panel with a non WAAS 430. It's perfect for everything I do and I can't justify spending big bucks for an updated latest greatest panel or even WAAS. I would way rather spend the money on gas and fly a lot, which I do. In reality around here the instrument rating is really only good for about 6 months due to the MEA's and the freezing level. You'll probably find yourself practicing to stay current/proficient more than anything. If you keep track of the instrument approaches that you actually have to fly in IMC they'll probably be few. (how often do we choose to fly on bad weather days?) But ya, for me the instrument rating is perfect for those marine layer days around here when you just want to get out or back. Usually the LPV approaches are just a few hundred feet lower than LNAV anyway. If you get in a pickle you can always just find an ILS. If you as a sport flyer have to fly an LPV or ILS to minimums you may want to look at your decision making.

Talk to the guys with thousands of hours like Rosie or Turbo not the guys with $50K panels who have never shot an approach.

That said WAAS is great and so are LPV approaches. The latest panels are definately the cat's meow. If you have the money and want the best then by all means go for it. Definitely not required though for the way most of us fly.

[Auburntsts]

At the end of the day, it?s not about the boxes. It?s about your ability to safely operate in the system in IMC. Define your mission and decide if your knowledge, attitude flying skills, and equipment are up to the task and produce a level of acceptable risk to you. Then set and abide by your limitations accordingly.

[Roger]

Thanks everyone for the great replies. I guess my problem is that I'm confused by all the advertising and the hype for all the fancy black boxes. I've had my instrument rating since 1976, and have rarely flown hard IFR, I prefer to file an IFR flightplan just to be in the system especially in the congested northeast where we now call home.

I know this may be opening another can of worms, but if any of you either recently or are currently looking to build an "inexpensive" IFR panel, what would you equip it with? I'd like an EFIS with a nav radio capable of ILS and at least LNAV approaches.

Thanks again for all your help, it's greatly appreciated!

Roger

[Auburntsts]

Originally Posted by Roger

Thanks everyone for the great replies. I guess my problem is that I'm confused by all the advertising and the hype for all the fancy black boxes. I've had my instrument rating since 1976, and have rarely flown hard IFR, I prefer to file an IFR flightplan just to be in the system especially in the congested northeast where we now call home.

I know this may be opening another can of worms, but if any of you either recently or are currently looking to build an "inexpensive" IFR panel, what would you equip it with? I'd like an EFIS with a nav radio capable of ILS and at least LNAV approaches.

Thanks again for all your help, it's greatly appreciated!

Roger

For my money I'd go with any of the usual suspects as far as EFIS brands (AFS, Dynon, Garmin, GRT, etc) and pair it with a non-WAAS GNS430. The EFIS choice really boils down to personal preference on features, number of screens, how info is displayed, buttonology, etc which you'll just have to do the research and decide for yourself.

Bear in mind that cheapest option may not be the best option due to lack of product support so make sure future support/database availability is part of your calculus.

[Canadian_JOY]

Roger - this game of IFR can be really "hard on the head" if one is coming from the staid old days of Cessna or Piper making all the decisions for you.

When you ask the question the way you have, you're going to get answers that range from soup to nuts.

Let me see if I can demystify this for you a little bit.

Firstly, WAAS is just an enabling technology - whether a receiver has a built-in WAAS receiver or not makes little difference. What does make a difference is the TSO to which the receiver is qualified. That TSO tells us the capabilities of the box, and it's those capabilities that dictate the approaches you can fly.

There are older boxes on the market that will allow enroute and non-precision approaches using GPS. There are also older boxes, namely the Garmin GNS480, which will do everything the more modern boxes will do in terms of enroute and approach navigation. I mention the 480 because it's about the best bang for the buck going at the moment. Used 430W's are still commanding a big dollar, big enough that I would spend the extra money to buy a new GTN650 or Avidyne IFD440 rather than buy a multi-year-old box at nearly new prices. The 430W is a good box but, in my opinion, over-priced in today's used equipment market.

GPS navigators are going to have to talk Arinc 429 in order to provide the information needed to perform GPS precision approaches. This means your EFIS selection will also have to include Arinc 429 interface capabilities. Likewise for your autopilot if you wish it to fly coupled approaches.

So how does one get an inexpensive IFR panel? The cheapest way is to go with a VOR/ILS receiver, but we know those approaches and airways are going away, replaced by GPS-based approaches and airways. This being the case, one can spend money now on a VOR/ILS solution but you'll later end up spending the money to get the GPS navigator that will open up all the airports into which you want to fly.

If I were looking at going bargain basement I would likely buy a used legacy GRT EFIS product with Arinc 429 interface and couple it to a used GNS480/CNX80. That way you could upgrade your legacy screens to the newer, higher resolution glass at fairly minimal cost ($2400 each) when money becomes available. Likewise, you could compliment the GNS480 with another box further down the road, even if that other box is a straight 430, an SL30 or similar nav/com. This gives you some redundancy in both navigation and communication.

Keep in mind that the more radios you put in, the more you're going to need a good audio panel to manage them. My best advice to anybody doing a panel upgrade is to start first with the audio system and upgrade it to a full audio panel and equip the audio panel wiring with inexpensive D-Sub connectors which allow you to quickly and easily connect in a new radio when you decide it's time to add a radio to the stack. Don't scrimp on the audio panel - after all, it's controlling the noise that's being piped into your head for every minute you fly your airplane.

[Ian Coates]

How about Garmin get a TSO for the GPS20A and then add the ability to upload IFR approaches with LPV on to the G3X touch.

[Canadian_JOY]

Originally Posted by Ian Coates

How about Garmin get a TSO for the GPS20A and then add the ability to upload IFR approaches with LPV on to the G3X touch.

Great idea, however they would also have to get TSO on the G3X as a flight management system in order to meet the requirements. The GPS20A would be a position "sensor" providing information to the flight management system. It's been done before, but not at anything like "experimental" pricing, so we're right back to spending $10K on a panel-mount TSO'd navigator as being the best option available.

[Roger]

Originally Posted by Canadian_JOY

Great idea, however they would also have to get TSO on the G3X as a flight management system in order to meet the requirements. The GPS20A would be a position "sensor" providing information to the flight management system. It's been done before, but not at anything like "experimental" pricing, so we're right back to spending $10K on a panel-mount TSO'd navigator as being the best option available.

And that Sir, is my (our) problem. How to build an IFR panel now that is not going to need extensive replacement in a few years, yet cost in the 5 AMU range?

Roger

[Canadian_JOY]

Roger - the $5K price point completely rules out TSO C145 GPS navigators since that's about the very bottom end of the price spectrum for that type of device and you'd have to be a good shopper to find one at that price. You'd be left with zero dollars for an EFIS.

Picking up a used legacy EFIS will run you $1-2k. They do come up for sale here from time to time, including recently a dual screen legacy GRT system. With this being the case your budget of $5K leaves you enough money for an EFIS and something like an SL30 NAV/COMM and that's about it.

While your CFO might not like it, stretching the budget to $10K will get you very well into IFR territory with a TSO C145 navigator (which also does VOR/ILS and is a COMM radio, too!).

I updated our panel from a good solid VFR panel with a legacy GRT WS EFIS and an SL30 in it. With the addition of a GNS480, a TruTrak Vizon 385 autopilot, a GRT Mini-X EFIS and an upgrade of the WS EFIS to an HX I came in at a bit over twice your budge but now have a very, very capable airplane with nice redundancy built in.

[GalinHdz]

Originally Posted by Roger

And that Sir, is my (our) problem. How to build an IFR panel now that is not going to need extensive replacement in a few years, yet cost in the 5 AMU range?

Roger

Can't be done, legally. It boils down to pay me now or pay me later.