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-   -   430W vs SL30 question (https://vansairforce.net/community/showthread.php?t=110547)

jchang10 03-07-2014 03:00 PM

430W vs SL30 question
 
Hi, i have a question i am hoping someone can help with.

Let's say i want to compare the capabilities between a 430W vs. a 400W and an SL30.

Since the com/nav/gps are all combined in the 430W, does it have any extra capabilities vs. having the functions separated in a 400W and the nav in the SL-30?

For instance, you could have a flight plan that takes you from a VOR into a GPS approach. Is the 430W smart enough to know this, and thus automatically switch your navigation from VOR to GPS for you somehow? or prompt or alert you to this somehow?

Thus in comparison, if it's the 400W and an SL-30, you will have to manually switch from the VOR to the GPS as your nav source to your control head somehow.

I am just trying to evaluate my options for a GPS panel upgrade.

Thanks!
Jae

RV8iator 03-07-2014 03:41 PM

On the 430 you still have to switch from GPS to VLOC to get the data out properly. In other words, if you are flying on the GPS and set up and ILS, you have to manually push the CDI button on the 430 when you begin the approach to utilize the LOC/GS. Inversely, after the missed if you are using the GPS to navigate, you must reselect GPS.

Not sure about the 400. The SL30 is VOR/LOC/GS only anyway so you can't switch.

Hope this helps.

BobTurner 03-07-2014 03:57 PM

The 430W will not switch from VOR to GPS automatically. However, it may automatically switch from GPS to LOC. First, there is an internal menu setting to turn this function on or off. Second, you must have loaded the ILS into the 430. Finally, there is some criteria that must be met - something like at least 2 miles outside the FAF, so if you get vectored in too close it won't switch. Frankly because of all the variables I recommend pilots get in the habit of switching manually. OTOH....
I have a 420W and an SL30 feeding a GRT HX EFIS. If I arm the ILS approach on the HX, then it searches all the nav inputs looking for a localizer frequency, and, at intercept, automatically switches from GPS (or heading hold, if in that mode) to the localizer signal.
Plus/minus between a 430W plus #2 com, or a 420W and an SL30:
Sl30 is a superior vor, actually two VORs or one vor/one ILS in one box.
SL30/420 doesn't put all your eggs in one box
430W/second com is about $1K cheaper.

Radomir 03-07-2014 05:55 PM

There's no need to be in VLOC mode if you're navigating to a VOR and then going into a GPS approach. You can stay in GPS mode throughout...

single 430W *may* be cheaper than 400+SL30... depends on what you can find on the market.. or may be a wash..

If you go with an EFIS (any) you'll have to switch something somewhere regardless of whether you use standalone 430 or 400+SL30 when you go from GPS nav to ILS.. though as mentioned, 430 has a capability to automatically switch from GPS to VLOC.

BillSchlatterer 03-07-2014 06:03 PM

VOR ?
 
Quote:

Originally Posted by BobTurner (Post 860240)
The 430W will not switch from VOR to GPS automatically. However, it may automatically switch from GPS to LOC. First, there is an internal menu setting to turn this function on or off. Second, you must have loaded the ILS into the 430. Finally, there is some criteria that must be met - something like at least 2 miles outside the FAF, so if you get vectored in too close it won't switch. Frankly because of all the variables I recommend pilots get in the habit of switching manually. OTOH....
I have a 420W and an SL30 feeding a GRT HX EFIS. If I arm the ILS approach on the HX, then it searches all the nav inputs looking for a localizer frequency, and, at intercept, automatically switches from GPS (or heading hold, if in that mode) to the localizer signal.
Plus/minus between a 430W plus #2 com, or a 420W and an SL30:
Sl30 is a superior vor, actually two VORs or one vor/one ILS in one box.
SL30/420 doesn't put all your eggs in one box
430W/second com is about $1K cheaper.

What's a VOR ? :) You will use the 430Waas/GPS capability 99% of the time. The precision GPS approaches on the 430W are terrific when coupled to a TruTrak AP. Will put you (literally) on the 1000 foot marker every time. Better than an ILS in my .02. A 430W and the new Garmin Com would make a great combination unit. I have an SL40 and being able to monitor the 430W plus two other frequencies on the SL40 is really handy!

BobTurner 03-07-2014 06:36 PM

Quote:

Originally Posted by BillSchlatterer (Post 860266)
What's a VOR ? :) You will use the 430Waas/GPS capability 99% of the time. ............
Better than an ILS in my .02.

Well, maybe 98% of the time you'll use the GPS. -:)

My last instrument student had a perfect day, weather wise, for his cross country. We planned the LPV approach at KCIC. But its minimums were "only" 300' and 1. Weather kept going downhill, and when we got there it was down to 200 and 1/2. The ILS got us in. At 300' AGL we were solid IMC, the LPV would not have worked.

It's not too often, but sometimes nothing but the ILS will get you where you want to be.

BillSchlatterer 03-07-2014 07:24 PM

Quote:

Originally Posted by BobTurner (Post 860275)
Well, maybe 98% of the time you'll use the GPS. -:)

Weather kept going downhill, and when we got there it was down to 200 and 1/2. The ILS got us in. At 300' AGL we were solid IMC, the LPV would not have worked.

It's not too often, but sometimes nothing but the ILS will get you where you want to be.

OK, but that's kinda like saying "is there light IFR?" and the answer is absolutely ... but just not at 200 & 1/2 :) and for the other 1% there are lots of LPV approaches where there is no ILS! Let's have them both ;)

Dbro172 03-07-2014 07:49 PM

Quote:

Originally Posted by jchang10 (Post 860226)
Hi, i have a question i am hoping someone can help with.

Let's say i want to compare the capabilities between a 430W vs. a 400W and an SL30.

Since the com/nav/gps are all combined in the 430W, does it have any extra capabilities vs. having the functions separated in a 400W and the nav in the SL-30?

For instance, you could have a flight plan that takes you from a VOR into a GPS approach. Is the 430W smart enough to know this, and thus automatically switch your navigation from VOR to GPS for you somehow? or prompt or alert you to this somehow?

Thus in comparison, if it's the 400W and an SL-30, you will have to manually switch from the VOR to the GPS as your nav source to your control head somehow.

Thanks!
Jae

Whether you have a 430W, or a 400W and an SL30 ran with a G3X you will still have to press the CDI button on the 430 or G3X to switch the NAV source being used from VOR (VLOC in Garmin nomenclature) to GPS. If you already have an SL30 than the 400W would be a simple add. If you have neither, from a cost standpoint you could probably get into a GTN650 for less than a new SL30 and 400W. I'm in the process of replacing my Aera 500 with a 400W and piping it to the G3X along with an existing SL30. For me this was waaaaay easier than going the 430W route. Way more wires on the back of a 430w than a 400w.

On the other hand with either a 400 or 430 you wouldn't necessarily have to navigate to a VOR using the physical omnidirectional VOR signal itself and then switch over to GPS as you say above. You could simply load the VOR waypoint in your flight plan and navigate to it using GPS

MarkW 03-08-2014 05:24 AM

Up until recently I flew with a 430W and got used to swapping between gps and vloc manually.
I now have a GTN650 and it has a lot of nice features that the 430 did not.
It moves to the vloc automatically.

Capflyer 03-08-2014 06:21 AM

The only advantage to having the 400W + SL30 is that the SL30 allows you to monitor both the back-up comm and nav frequencies. If that is not important or you already have a com2 then go with the 430W. Less wiring, less hassle, and probably about the same cost. For someone like me that already has an SL30 and no IFR GPS the 400W is a good fit as an add-on unit especially since I do not have another com radio. Actually, on second thought I'd probably just add the 430W and use the SL30 as my com2.


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