Well, for starters I received my CFII certificate about two months ago but finally had the opportunity to have my first instrument student a few days ago and of course came across my first question since I hadn't flown anything instrument related for about two months. My question is when flying a published hold with a G430 on say a VOR approach (to just fly the published missed) do you go direct to whatever the NAVAID is on the approach plate and set the OBS off that course since that will give you accurate DME reading for the hold? Or just select procedure and go direct to the missed hold and base it off that (with zero essentially being your cue to start turn outbound)? I taught it off the NAVAID since that gives accurate DME reading and you need it to shoot the approach anyway but was wondering if anyone does it different?
New CFII question...
- Thread starter ou9692
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If you're coming to the hold after doing the VOR approach (I'm assuming it's a VOR only approach, with the approach loaded into the 430 to provide DME), you should have the CDI being driven by the VOR, and the 430 would have automatically sequenced to the hold when you took it out of suspend when passing the MAP.
If you're just doing the hold alone (without having flown the approach), the easiest way would be to have the 430 go direct to the VOR to provide DME, with the CDI again being driven by the nav radio while doing the hold.
In either case, the 430 will show the distance to the VOR being somewhere close to zero when you start the turn outbound (since the VOR flag flip won't occur exactly when the 430 says you're at the VOR), but if the hold is started from the approach menu, the 430 will provide prompts on the entry type, as well as guidance as to when it thinks you should turn during the entry.
If you're just doing the hold alone (without having flown the approach), the easiest way would be to have the 430 go direct to the VOR to provide DME, with the CDI again being driven by the nav radio while doing the hold.
In either case, the 430 will show the distance to the VOR being somewhere close to zero when you start the turn outbound (since the VOR flag flip won't occur exactly when the 430 says you're at the VOR), but if the hold is started from the approach menu, the 430 will provide prompts on the entry type, as well as guidance as to when it thinks you should turn during the entry.
gotWXdagain
Polished Member
G430 is fully IFR certified for all phases of flight, so under normal circumstances there's no reason not to fly the entire missed approach procedure with your CDI set to the GPS. It will even do timed holding patterns for you, as long as the hold is published. Really, the only segment of the approach that you cannot fly with the CDI set to the GPS is the final approach course. Now, if you're training the student on VOR procedures and its early on in their training, it's a good idea to keep them away from the GPS completely if DME is not required by the procedure, or at least let them set Direct to the VOR to find distance if it is required.
n57flyguy
Well-Known Member
I will always use my second navigation source as my primary indications on a VOR approach. I will have the 430 in GPS mode for enhanced situational awareness, as you can obviously have the bigger picture in mind with a map or nav page to help. That better allows to be ready in the event a missed approach has to be conducted. The best part is it allows for redundancy in the event of an equipment failure of your Nav 1 or Nav 2 source. The caution being is to make sure the needle does not fully deflect on your Nav 2. Usually it does not, but I know of a local approach that gets it close if you are following the GPS CDI indications. It is a legal, redundant, and a safe method.
If your primary navigation is sole reliance on the 430, I like the idea of keeping the 430 on GPS till just before the FAF. I had never thought of that, being fortunate enough to fly airplanes with two means of navigation. Before that point though, I am sure once the approach is selected a message will show up reminding you that you are in GPS mode and that it will only serve as guidance. When you hit the CDI button, does that require you to reload and reactivate the approach? Or does it automatically register that you are no longer on GPS guidance?
MidlifeFlyer
Well-Known Member
When you hit the CDI button, you are telling the box to use its VOR head for lateral navigation. There's nothing to reload.
ou9692, the rule is that on a VOR (NDB, LOC, ILS) approach, GPS can be used for everything except lateral guidance on the final approach course - that has to be the type of navaid in the title of the approach.
The most common methodology seems to be to load the approach, keep the CDI in GPS mode about to intercept the final approach course and then switch the CDI for the intercept itself. Then switching back to GPS mode for guidance for the missed.
I know a number of people who make the switch earlier, say, at the time of loading the approach or once being vectored. I think waiting until on an intercept to the FAC has two advantages.
One is utility. In GPS mode, you will have CDI guidance for the full approach including the procedure turn. With a autopilot, the airplane will fly it all; with a GPSS autopilot, the airplane will fly it with no input from the pilot.
The other is consistency. Once one accepts the utility of using the GPS to it full legal ability, there's much to be said for having a SOP you are less likely to forget and there doesn't seem to be any good reason to change procedures depending on whether you are being vectored or flying the full approach or whether you have an autopilot or not.
n57flyguy
Well-Known Member
That makes sense, I didn't think it would but I'd rather ask.
I can agree with the bold text, however if I am on vectors for the approach, I would rather be ahead a step ahead as the vectors are my means of getting to the FAC. I see the point of redundancy though, especially with one nav source. The second point of consistency is excellent, almost not mentioned enough.
MidlifeFlyer
Well-Known Member
Thank you. Probably obvious from my post, but I think it needs to be mentioned more, particularly in training. Especially when we get to IFR, aircraft control should be pretty ingrained and most (maybe even 90%) of what we do is procedural. I don't know what the psychologists would say, but I think having a consistent set of SOPs reduces workload and decreased the likelihood of errors.
You're a step ahead either way. Let's suppose you are flying a full approach in a GNSS-equipped airplane and letting the autopilot do the work. You're not sitting there doing nothing. You're anticipating what you're expecting George to do, probably twisting the CDI or HSI to the current course, anticipating the final intercept as the airplane flies the PT so you can switch the CDI to the VOR/LOC, preparing for whatever configuration change you do as you cross the FAF/GSI to start down. You're way ahead of the airplane. In the vectors to final situation, you'd be doing all the same things and being just as far ahead.
But it doesn't really matter - if your choice is to make the change on a vectored approach when vectors begin and delay when doing a full approach, it works just as well and becomes your SOP for those situations if consistently applied. The flip side of creating a SOP is sticking with it and IMO the worst fault a CFI can have is to change someone's SOP so long as it works and doesn't present a safety problem.
n57flyguy
Well-Known Member
That is a good point about psychology, I have personally started a study on Human Factors and Aviation Psychology. There are a few premises I am looking into, but one is the IFR environment in itself. Now, while I am by far not the most experienced in the field, I am trying to better define experience and how we as pilot make aircraft control ingrained to our human element of coordination and reading the instruments. You could take it a step further to analyze spatial orientation and disorientation.
Consistency is key to a lot in any flying. A friend of mine, upon completion of my PPL, told me when we take off (MD-80) we have 5 fingers up on either side. As we speed up down the runway, we start taking fingers away, then we take off. That was one example he gave me of a few. When flying IFR I took that a step further into every component of the flight. On departure I had these options, as I continued on, they diminished. Same for enroute, the approach, and landing. What I found was that when I consistently planned for those options to be used, I was consistently ahead of the airplane, and in turn was consistently improving my IFR flying. It felt like I was doing things right, and I am satisfied with the result. It is far better to throw away the options you have thought of when before hand, than being in actual and having an issue you could have thought about more.
That reminds me when I was doing a currency flight recently. The CFI I was with states "you would have just failed your ride." I was about 3nm out on his vectors for a practice ILS before the OM. Why? I had not yet switched to VLOC while on vectors. Maybe that is my preconception of why the discussion has come to be, and my previous training of having always switched to VLOC well before that point. I see your point now, it really doesn't matter, as long as your SOP accounts for not forgetting to make the switch on the FAC. I like it, thanks for the thoughts and knowledge. Time to try a few new things!