Aeronautical Working Groups - Navigation impacts

[kmac]

It’s that time of the year again for the DoD aeronautical working groups. It would be great if we had participation from actual operators, but the reality is that only USAF has supported this (by way of AFFSA). There are always plenty of topics impacting the flying community, so if you had the opportunity to have your voice heard, what would you say?

What are your thoughts on continuous descent final approach? Is any community training to this, as opposed to getting to MDA prior to the MAP? On the civil side, approach visibility minimums increase on some approaches if you don’t fly CDFA. The rule for civil operators is now being applied by DoD TERPs shops and I doubt they’ve all talked with the flyers about operational impacts.

Speaking of visibility, do you use the first mentioned visibility value in the minima, or do you only use the parenthetical value when it comes to planning and/or starting the approach? Have you ever wondered why we repeat the same visibility value? I have.

Do you use the final approach course bearing line in the airport sketch for awareness as to your orientation to the runway environment? For approaches where the final is offset from the runway, would you rather exclude the line in the sketch or change the scale of the airport sketch to include the line?

If you need some approaches into a field that isn’t in FLIP, do you know how to request them to be included?

Have you used the electronic instrument procedure library (E-IPL)? Why or why not?

Is there anything you would change? Why?

Thanks for your inputs!

 

[Sniktau]

As a graduate of the USAF AIS program I’d love to get the Navy on board with getting rid of the NATOPS IFM, take the important stuff and toss it into 3710, and tell pilots to reference the FAR/AIM for everything else like our silver winged brethren did with their two separate pubs.

If there’s an actual way for a bored shore duty LT to get involved in these working groups please let me know.

 

[ChuckMK23]

Great stuff!

At least in CONUS, RNAV with vertical guidance is widely available - and seems better every year. Even LP only, on Garmin equipment (G1000, GTN series, etc) there is advisory vertical guidance displayed on PFD. Garmin has some sort algorithm when the advisory vertical guidance is displayed - because it is inconsistent.

CDFA with a DDA of MDA+50' is the order of the day. This is especially useful in missed approach scenarios where you now simply put the Missed Approach Altitude in Altitude Preselect window/MCP regardless of type of approach. You get to the DA or DDA and if you dont see the field you TOGA and go missed. Its same flow regardless of approach type.

I'm sure its an altogether different story in rest-of-world. Plenty of NDB and VOR approaches out there. Seems like most modern aircraft have a means to compute a advisory glidepath that honors all crossing restrictions. I believe this is a feature of all Jepp databases that even older FMS use.

 

[JTS11]

Great stuff!

At least in CONUS, RNAV with vertical guidance is widely available - and seems better every year. Even LP only, on Garmin equipment (G1000, GTN series, etc) there is advisory vertical guidance displayed on PFD. Garmin has some sort algorithm when the advisory vertical guidance is displayed - because it is inconsistent.

CDFA with a DDA of MDA+50' is the order of the day. This is especially useful in missed approach scenarios where you now simply put the Missed Approach Altitude in Altitude Preselect window/MCP regardless of type of approach. You get to the DA or DDA and if you dont see the field you TOGA and go missed. Its same flow regardless of approach type.

I'm sure its an altogether different story in rest-of-world. Plenty of NDB and VOR approaches out there. Seems like most modern aircraft have a means to compute a advisory glidepath that honors all crossing restrictions. I believe this is a feature of all Jepp databases that even older FMS use.

What happens when you go failed card on that NDB? 😄

 

[ChuckMK23]

What happens when you go failed card on that NDB? 😄

HELMET FIRE!!!!!!

 

[ChuckMK23]

@kmac from an office colleague - Active Duty STAN-EVAL dude:

The CDFA is excellent vs dive and drive and with updated G1000 software can be easier than ever in cases wherein a vertical path or slope is unavailable, the aircraft MAY provide +V guidance which is not meant to be a guarantee for obstacle clearance, but in all cases should be a near perfect CDFA path to minimums. Otherwise with any other APV you know you have TERPS approved obstacle clearance to the minima (same on a glideslope if flying the ILS). Since most approaches offer LPV or LNAV/VNAV minima it's easy to see this on LP approaches in newer aircraft you'll potentially see an LP+V offering.

The pro's are the approach is much more stable can be flown to either a DA or DDA and the decision is simple with a "minimums" callout from the aircraft.

 

[kmac]

As a graduate of the USAF AIS program I’d love to get the Navy on board with getting rid of the NATOPS IFM, take the important stuff and toss it into 3710, and tell pilots to reference the FAR/AIM for everything else like our silver winged brethren did with their two separate pubs.

If there’s an actual way for a bored shore duty LT to get involved in these working groups please let me know.

Who actually writes the IFM? There are lots of things that seem outdated in it. An Army colleague of mine just went through AIS and had a question regarding distance based holds. How do you enter them with a teardrop procedure? Do you time for a certain distance, strictly use DME, or some combination of both? We ended up looking at the FTIs for T-6B, T-44, and T-45 instrument training. All gave a slightly different version of what to do. His gripe was that the USAF has a consistent answer, but neither the USA or USN do. The USAF has definitely made a concerted effort to be more civilian-like than the other services.

@kmac from an office colleague - Active Duty STAN-EVAL dude:

The CDFA is excellent vs dive and drive and with updated G1000 software can be easier than ever in cases wherein a vertical path or slope is unavailable, the aircraft MAY provide +V guidance which is not meant to be a guarantee for obstacle clearance, but in all cases should be a near perfect CDFA path to minimums. Otherwise with any other APV you know you have TERPS approved obstacle clearance to the minima (same on a glideslope if flying the ILS). Since most approaches offer LPV or LNAV/VNAV minima it's easy to see this on LP approaches in newer aircraft you'll potentially see an LP+V offering.

The pro's are the approach is much more stable can be flown to either a DA or DDA and the decision is simple with a "minimums" callout from the aircraft.

CDFA is nice if you’re willing to “give up” early, especially when a MAP is at the threshold. I’ve always seen the Navy as accepting more risk for the operational benefit of increasing the odds of making a runway, even if it’s not a “stable” approach. For the commercial guys that spend the vast majority of time shooting approaches with vertical guidance, a lot of them suck at descending to an MDA and leveling off. The CFIT issues that occurred on the civilian side are highly mitigated by CDFA. However, I have not seen any evidence to indicate CFIT from an instrument approach has been a problem for the military, which is much more proficient on non-precision approaches.

I’ve also heard that the heavy guys use CDFA but pretty much no one else does. Is that true?

 

[Sniktau]

Who actually writes the IFM? There are lots of things that seem outdated in it.

It’s owned by VT-31 from what I recall. After going through AIS seeing how AFFSA is organized made significantly more sense to me than how we’ve split up the responsibilities between CNAF, CNATRA, and NAVFIG both literally and physically.

 

[IKE]

It’s owned by VT-31 from what I recall. After going through AIS seeing how AFFSA is organized made significantly more sense to me than how we’ve split up the responsibilities between CNAF, CNATRA, and NAVFIG both literally and physically.

The model manager should be identified in the front matter. You could always contact CNAP N455, Force NATOPS to find out too.