I am working on getting my IFR certification. To get my plane IFR legal I am considering adding either a GPS175, GNC355 or Avidyne's IFD 410 to my RV14 (with Dynon HDX, radio, & AP). Interested to hear others thoughts.
Van's Air Force
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IFR - GPS175, GNC355 or IFD410
- Thread starter ben barron
- Start date
I went with the 175 when I equipped (life got in the way of finishing my rating). I wanted a second radio so I picked up a 2nd hand audio panel and MGL N16 Nav radio, V16 VHF and Razor head (in Canada I needed a second nav source). This was the less expensive way to equip, rather than the 355 which would have still required a Nav radio.
If the 175 vs 355 decision is about the 2nd Com, take a look at cheaper Com options. Might not be worth it for you like it was for me. All in all the 175 (and 355) is plenty of GPS Nav. You'll be happy with the HDX+AP+175 combo when it comes to coupled approaches. Does a fine job.
If the 175 vs 355 decision is about the 2nd Com, take a look at cheaper Com options. Might not be worth it for you like it was for me. All in all the 175 (and 355) is plenty of GPS Nav. You'll be happy with the HDX+AP+175 combo when it comes to coupled approaches. Does a fine job.
Ed_Wischmeyer
Well Known Member
Usability is something that is almost never discussed, other than the occasional manufacturer talking about "intuitive..."
Here are things to consider when you choose your GPS box:
* How easy is it to determine which transition you want on a standard T shaped LPV approach so that you can select that transition?
* How easy is it to change from one transition to another on the same approach? (The hard one might be to change from vectors to final to a "real" transition.)
* How easy is it to edit a flight plan in flight, to add or remove a waypoint, or even just to see what the waypoints are?
* How much scrolling of the screen is required to get to the button that you need next?
* How much useful information can be displayed without any screen manipulation? for example, time and distance to the next waypoint, time and distance to the destination, ETA at the destination.
* Double check for gotchas, like distance to destination is along the flight plan, and if ATC gives you a shortcut and you don't modify the flight plan, the distance to destination thinks that you need to go back to the bypassed waypoints.
* Look for user interface compatibility between what's already installed and what you're considering. I'm not totally up to speed on this one, but one major GPS sometimes required pushing the Enter button twice, but other avionics didn't.
* Double think whether you really need a second comm, and how you would actually use it on a flight. If you think you would use both comms, when would you tune which to what? A worst case is at a Class C airport, with clearance, ground, tower, departure, change to the other departure. Or landing, with a similar reverse sequence. (Just remember that once you're off the runway, that's a good time to stop and take a deep breath to avoid taxi errors or worse, a runway incursion.) There will probably be lots of comments on this that will not be based on what the true needs and use cases are.
* If you're flying a high value RV-14, don't depreciate it with a cheap or disorganized panel.
* What's your strategy for mastering the new system, not just learning enough to pass a flight check? New systems are so configurable and have so many bells and whistles, gongs and chimes, etc. etc. and then some...
* How much does your CFII know about the new system? Does s/he know the easy way to do things, and all the shortcuts, or just the basics? (One of the major learning objectives of instrument flying is cockpit workload management, meaning, when do you have time in flight to fuss with the avionics and get them all set up for what you want. Glass cockpits are great once everything is set, but setting things up can be a high workload task.)
Sure, you can get around all of these considerations with a little bit more cockpit workload, but that extra workload could come at an inconvenient time under challenging circumstances. That extra workload also means more training and more to keep current on, and more possibility of mistakes. (On another forum, there was discussion on IFR go arounds at minimums. I choose to log those because to me, they are at least as important as holding patterns.)
Go spend some time with real people who know the systems you're considering and know you. This site might help you ask the right questions, but the quality of the answers can be all over the map.
Good luck!
Ed
CFII/ATP, lots of user interface work in my career
Here are things to consider when you choose your GPS box:
* How easy is it to determine which transition you want on a standard T shaped LPV approach so that you can select that transition?
* How easy is it to change from one transition to another on the same approach? (The hard one might be to change from vectors to final to a "real" transition.)
* How easy is it to edit a flight plan in flight, to add or remove a waypoint, or even just to see what the waypoints are?
* How much scrolling of the screen is required to get to the button that you need next?
* How much useful information can be displayed without any screen manipulation? for example, time and distance to the next waypoint, time and distance to the destination, ETA at the destination.
* Double check for gotchas, like distance to destination is along the flight plan, and if ATC gives you a shortcut and you don't modify the flight plan, the distance to destination thinks that you need to go back to the bypassed waypoints.
* Look for user interface compatibility between what's already installed and what you're considering. I'm not totally up to speed on this one, but one major GPS sometimes required pushing the Enter button twice, but other avionics didn't.
* Double think whether you really need a second comm, and how you would actually use it on a flight. If you think you would use both comms, when would you tune which to what? A worst case is at a Class C airport, with clearance, ground, tower, departure, change to the other departure. Or landing, with a similar reverse sequence. (Just remember that once you're off the runway, that's a good time to stop and take a deep breath to avoid taxi errors or worse, a runway incursion.) There will probably be lots of comments on this that will not be based on what the true needs and use cases are.
* If you're flying a high value RV-14, don't depreciate it with a cheap or disorganized panel.
* What's your strategy for mastering the new system, not just learning enough to pass a flight check? New systems are so configurable and have so many bells and whistles, gongs and chimes, etc. etc. and then some...
* How much does your CFII know about the new system? Does s/he know the easy way to do things, and all the shortcuts, or just the basics? (One of the major learning objectives of instrument flying is cockpit workload management, meaning, when do you have time in flight to fuss with the avionics and get them all set up for what you want. Glass cockpits are great once everything is set, but setting things up can be a high workload task.)
Sure, you can get around all of these considerations with a little bit more cockpit workload, but that extra workload could come at an inconvenient time under challenging circumstances. That extra workload also means more training and more to keep current on, and more possibility of mistakes. (On another forum, there was discussion on IFR go arounds at minimums. I choose to log those because to me, they are at least as important as holding patterns.)
Go spend some time with real people who know the systems you're considering and know you. This site might help you ask the right questions, but the quality of the answers can be all over the map.
Good luck!
Ed
CFII/ATP, lots of user interface work in my career
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