skysurfer007 is a youtube poster with good explanation on PMDG and different approches. Since he is a real world pilot I find his simulation providing practical information. Some of his simulations are in German. Despite German, one understands most things in general. Notice following publication, part 2:

 

 

Here, he shows in detail LNAV VNAV NDB DME Approach, EDLV. It's an slow but exacting approach. Is this an approach which is actual in real life aviation when expecting NDB approach? I mean using VNAV/LNAV at final turn down to, in his example 800 ft and then turning off AP? Using VNAV/LNAV at final turn down to 800 ft seems quite effective ..but is this just a FSX simulation detail?

 

Sincerely

 

Geir

Here, he shows in detail LNAV VNAV NDB DME Approach, EDLV. It's an slow but exacting approach. Is this an approach which is actual in real life aviation when expecting NDB approach? I mean using VNAV/LNAV at final turn down to, in his example 800 ft and then turning off AP? Using VNAV/LNAV at final turn down to 800 ft seems quite effective ..but is this just a FSX simulation detail?

 

Without having the chart in front of me, I can't say exactly, but since it was up on the ND, I'd say you could expect this in real life at that airport if they had to resort to it. For what it's worth, in the US, as the NDBs go out of service, they're just no repairing them because we have a lot more advanced navigation and the upkeep just isn't worth it. If you look at a lot of the flight school syllabi, you'll see that NDB training is crossed out or omitted now. Some instructors will show you how to fly them, just in case it's your last resort, but you'll rarely ever see them.

 

In the case of the 73, I'd argue you're not going to fly an NDB approach all that often, as anywhere there's an NDB approach, there's often a more optimal GPS approach. I know procedures in approaches are highly dependent on company SOP, but I'm somewhat surprised he didn't have the NDB data up on the back up ADF. Not a huge deal and it's not necessarily wrong. Just something I noticed.

 

It was good to hear German, too. Was one class short of a minor in it in university, and I'm literally still alive because of that. Haven't really spoken the language since...

They don't teach NDB in US? So, when this student becomes an International Pilot and come flying to Brazil, what will he do when he's instructed by ATC an NDB Approach?

Refuse the NDB approach and take a visual if he is able. I used to hear horror stories of 727s flying NDB approaches and how badly the NDB equipment were affected by lightning making the approach impossible. I think most major airlines dont do NDB approaches any more, at least the ones with modern equipment.

Maybe in the US, but in many countries you have two options, NDB or go elsewhere, since the airport is IMC. But I agree NDB is an outdated technology, now with GPS it will become much better.

They don't teach NDB in US? So, when this student becomes an International Pilot and come flying to Brazil, what will he do when he's instructed by ATC an NDB Approach?

 

They don't much anymore, no. If the pilot never learns how to fly an NDB approach, to be honest, an approach is an approach, so he or she could probably figure it out. The issue would be accuracy and wind drift. You track NDBs differently than you would a VOR, or other navaid. Wind can play a much larger factor if you don't properly correct for it (if you correct wind drift by only realigning your nose to the NDB, you'll fly an arc), which could cause problems if you didn't know.

 

As far as being told to expect it, as I mentioned, it's not so likely here. In other countries, sure, but he or she could always decline it in favor of another approach (or another airport if that was the only option).

 

 

Refuse the NDB approach and take a visual if he is able. I used to hear horror stories of 727s flying NDB approaches and how badly the NDB equipment were affected by lightning making the approach impossible. I think most major airlines dont do NDB approaches any more, at least the ones with modern equipment.

 

Around storms - at least in my experience - it's not impossible. It's more of a nuisance than anything else. Then again, the storms I'd be flying around in a smaller plane aren't what a 727 might fly through, but lightning is lightning. Unless you're in a nasty electrical storm, you'll see it point at the lightning for as long as the lightning is around and then get back to business.

In the US if you cannot comply with a certain instruction or action the magic word to ATC is "unable".

...or better yet:

Unable, [reason].

 

...or best yet.

Unable, [reason], [counter offer].

 

Sorry. Just had to add that in there. Controllers are taught (or at least, I was taught) that it is good form to give reason. In some case, the 7110 mandates it (vectors must have reasons, as an example).

 

As such, I believe pilots should follow suit.

 

"Cessna 467, expect GPS Runway 21 approach."

Unable. No approach data in the unit. ILS 3 circle 21 or I can spin over GVE.

 

You know your skills, equipment and preferences. Don't make ATC play 20 questions to get there. Then again, in the future, you'll set your preferences electronically (yay NextGen!).

 

[/PSA]

Furthermore, many of the newest 737s rolling off the production line are shipping sans-ADF...

...or better yet:

Unable, [reason].

 

...or best yet.

Unable, [reason], [counter offer].

 

Sorry. Just had to add that in there. Controllers are taught (or at least, I was taught) that it is good form to give reason. In some case, the 7110 mandates it (vectors must have reasons, as an example).

 

As such, I believe pilots should follow suit.

 

"Cessna 467, expect GPS Runway 21 approach."

Unable. No approach data in the unit. ILS 3 circle 21 or I can spin over GVE.

 

You know your skills, equipment and preferences. Don't make ATC play 20 questions to get there. Then again, in the future, you'll set your preferences electronically (yay NextGen!).

 

[/PSA]

 

Yea I do the same and in fact I gave 2 reasons why I wanted to divert to PHOG during last night's FNO (unable to fly a holding pattern due to fuel and RW time constraint) but I chose to keep my post simple lol

Fair enough. No surprise I came in to use up a bunch of words...haha.

For us in europe, we still do have a lot of places with only NPA approaches to one of the runways whether that be a NDB in many cases or a VOR approach. And yes we do use LNAV / VNAV for those approaches in the 737 and it works like a charm, only thing you need to make sure you have the correct QNH in the FMC DEScent->FORECAST page, otherwise your VNAV path would not be correct and you could end up in a CFIT accident. (QNH is very important in every NPA approach because you don't have any other vertical guidance than your altimeter. Unlike an ILS where you have the G/S)

For us in europe, we still do have a lot of places with only NPA approaches to one of the runways whether that be a NDB in many cases or a VOR approach. And yes we do use LNAV / VNAV for those approaches in the 737 and it works like a charm, only thing you need to make sure you have the correct QNH in the FMC DEScent->FORECAST page, otherwise your VNAV path would not be correct and you could end up in a CFIT accident. (QNH is very important in every NPA approach because you don't have any other vertical guidance than your altimeter. Unlike an ILS where you have the G/S)

 

Interesting. I thought the active autopilot took vertical ques from the altimeter settings on the respective side alone; how does the DES FORECAST QNH influence things?

Interesting. I thought the active autopilot took vertical ques from the altimeter settings on the respective side alone; how does the DES FORECAST QNH influence things?

 

 

Well yes it does, for the MCP selected ALT. And also the stop altitudes from the FMC in VNAV.

 

But when doing a VNAV NPA, the FMC calculates a vertical profile/path to be followed by the aircraft from the runway point and up often 3 degrees as a normal G/S. But this Path is calculated with the QNH you set on the forecast page, set this incorrect and the FMC will calculate an incorrect VNAV path wich the aircraft will follow possibly in to terrain.

Well yes it does, for the MCP selected ALT. And also the stop altitudes from the FMC in VNAV.

 

But when doing a VNAV NPA, the FMC calculates a vertical profile/path to be followed by the aircraft from the runway point and up often 3 degrees as a normal G/S. But this Path is calculated with the QNH you set on the forecast page, set this incorrect and the FMC will calculate an incorrect VNAV path wich the aircraft will follow possibly in to terrain.

 

I still don't follow. Altitude constraints and vertical paths are constructed with respect to altitude above MSL. With the correct QNH selected on the EFIS panel you'll be flying with respect to the same altitude. How would the setting in the FMC change that?