FMS fundamentals for millennials

if you need an alternate single engine departure route, how do you set that up? split FMS 1 and 2 and have the alternate procedure loaded in the non-flying pilots side? The “FMS” in the PC-12 let’s you load a secondary flight plan and switch to it quickly but I don’t see that functionality anywhere in the UNS.
 
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if you need an alternate single engine departure route, how do you set that up? split FMS 1 and 2 and have the alternate procedure loaded in the non-flying pilots side? The “FMS” in the PC-12 let’s you load a secondary flight plan and switch to it quickly but I don’t see that functionality anywhere in the UNS.

Most single engine DP’s are not meant to be flown in the FMS, if you are using it, make sure that all the waypoints are fly over. A smart turn could be deadly.

On the UNS you split the boxes and have PIC side gets the normal, PM side gets the Taylor’s single engine dp. If the engine fails it’s one of the PM’s duties to switch nav sources for the PF.


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The single best part of the UNS-1 was that the VNAV was separate from the nav page- and it would stay in VNAV while you were plugging around on headings. If you were getting vectored to final and given an altitude close to the FAF ALT, plug it in and VNAV to it. Then as ATC turns you the airplane would modify the descent rate. The rate would change, but, you’d have a nice constant rate of descent to the FAF with no level offs etc. made for a smooth ride in.


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Or... you could divide the altitude you need to lose by 3. Add 1nm for every 10 kts of tailwind in the descent. (I won't even mention what to do with a headwind 'cause it would be like what the Harley riders say, "if you don't get it, I can't explain it".)

I know... math is hard... especially when arithmetic involves 3s or 7s.

Still, with a bit of dedication to practice during your driving commutes to the airport, after a month or so, YOU can be effectively as good as your FMS.
 
Or... you could divide the altitude you need to lose by 3. Add 1nm for every 10 kts of tailwind in the descent. (I won't even mention what to do with a headwind 'cause it would be like what the Harley riders say, "if you don't get it, I can't explain it".)

I know... math is hard... especially when arithmetic involves 3s or 7s.

Still, with a bit of dedication to practice during your driving commutes to the airport, after a month or so, YOU can be effectively as good as your FMS.

You are 22 miles away from the FAF, you have 4000 feet to lose. What’s your decent rate?


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You are 22 miles away from the FAF, you have 4000 feet to lose. What’s your decent rate?


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Not really what we're talking about, but I'm still your Huckleberry. 'Round 'bout 350-450fpm, yeah? I'm assuming an average speed of about 130 kts. If higher, well you know, increase your descent rate a schkotch. Approach descent rates vs speeds are like gallons to pounds relationships... there's a handful of 'em it really helps to memorize.
 
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if you need an alternate single engine departure route, how do you set that up? split FMS 1 and 2 and have the alternate procedure loaded in the non-flying pilots side? The “FMS” in the PC-12 let’s you load a secondary flight plan and switch to it quickly but I don’t see that functionality anywhere in the UNS.
In the vaunted G3000 (pseudo dual FMS [in most installations, it's not a dual FMS, but it plays one on TV]), the best technique is to -before departure- load a standby flight plan based on your APG escape route into your SINGLE FMS... then, after you get your engine failure event sorted and your aircraft aerodynamically stabilized and climbing, look down into the center console, then -turbulence allowing- touch the correct touch-screen buttons through a couple of menu levels, then select your secondary flight plan, then activate it, then become re-established on instruments per the new flight plan. Simple, concise, and efficient, yeah? Almost like the code kiddies designed it for REAL pilots in REAL emergencies, and the FAA approved it as a redundant system.
 
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Not really what we're talking about, but I'm still your Huckleberry. 'Round 'bout 350-450fpm, yeah? I'm assuming an average speed of about 130 kts. If higher, well you know, increase your descent rate a schkotch. Approach descent rates vs speeds are like gallons to pounds relationships... there's a handful of 'em it really helps to memorize.

Nope, because this is EWR, and you’re taking vectors for spacing, and will actually fly 52 miles, but, you won’t know this until your 5 miles from the fix.

The point being that the VNAV will continuously update the calculation as you take vectors. Resulting in a nice constant descent with no real level offs etc.

The easy math is easy- but knowing how to utilize the capabilities of your equipment and understanding how to get the most out of it is just as important.


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Nope, because this is EWR, and you’re taking vectors for spacing, and will actually fly 52 miles, but, you won’t know this until your 5 miles from the fix.

The point being that the VNAV will continuously update the calculation as you take vectors. Resulting in a nice constant descent with no real level offs etc.

The easy math is easy- but knowing how to utilize the capabilities of your equipment and understanding how to get the most out of it is just as important.


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I agree, unless it's broke, a computer will ALWAYS be better at rapid, repetitive calculations than will I, or will you. I completely understand your point. I did before, which you might have grokked had you taken my hint. Again, this is NOT what we were originally talking about, but bravo for adapting to today's latter-day method of muddying the argument and distracting for the "win". Go Vlad!!! At the end of the day, even stuff like THIS will likely soon end up becoming a "political issue," too. Lol. Gotta love the early 21st century. Go'murica!

If you MUST go there... FAF to MAP? Use your Jepp chart at 100 as your base line, or just have some experience with speed, distance, and height.

Final and main point... if you're flying an airplane at altitude and you don't -without a computer- have some general intuitive sense of when to start descending from cruise to your destination... you should NOT be flying an airplane.
 
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What if I told you, we don’t do this anymore? :)


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You would be absolutely correct - in a fashion similar to Microsoft tech support.

What if I told you... that statement of yours (as its own activity) falls squarely into the category of self-induced (by a small few who are mercenary and consequently profit) and/or self-accepted (by the many who don't know they're doing it and consequently suffer) dismissal and abrogation of human agency in the world. In the case of this convo, that statement of yours is the meta abrogation that hovers above and supersedes the egregious abrogation of aviation responsibility that it proposes and supports. Bigger picture hint: The aviation part withers in comparison to the dismissal of human agency.
 
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You are absolutely correct.

What if I told you... that statement of yours (as its own activity) falls squarely into the category of self-induced (by a small few who are mercenary and consequently profit) and self-accepted (by the many who don't even know they're doing it and consequently suffer) dismissal and abrogation of human agency in the world. In the case of this convo, that statement of yours is the meta abrogation that hovers above and supersedes the egregious abrogation of responsibility for aviation ability itself. The aviation part withers in comparison to the dismissal of human agency.

I’m not sure what all that ramblings about.

We fly a path airplane, as such, it’s published for us. So is the fancy threshold crossing height. This is the number we expect to see, we don’t use the 100 box. We also don’t use VOR’s for a vor approach. The overwhelming cause of check ride failures in turbine equipment are avionics/FMS/systems related these days - not BFS.
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I’m not sure what all that ramblings about.

We fly a path airplane, as such, it’s published for us. So is the fancy threshold crossing height. This is the number we expect to see, we don’t use the 100 box. We also don’t use VOR’s for a vor approach. The overwhelming cause of check ride failures in turbine equipment are avionics/FMS/systems related these days - not BFS.
fa63c91a610922aac01e0bdc65071ead.jpg



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Precisely, regarding your statement about checkride failures and excepting your lack of a condensation apostrophe in ramblings. So why are we bickering again???

Like I said -twice now- you are arguing with me about something largely unrelated to the point I was originally making.

But as long as we're on it, I never really had to do NDB approaches or misses or holds in real life. But doing them in training and testing definitely made me a better pilot with better geometric and spacial apperception. VOR approaches are still out there. Even if you don't ever have to do one, understanding how they are done and how to do them makes you a better aviator. It might even teach you something about the limitations of and differences between GBAS and SBAS and generic GNSS.

Why seek steak when ground offal mixed with cutting room detritus is available as a cheap and tasty burger??

Then again, it's all self-flying these days... maybe I need a refresher course!!
 
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Most single engine DP’s are not meant to be flown in the FMS, if you are using it, make sure that all the waypoints are fly over. A smart turn could be deadly.

On the UNS you split the boxes and have PIC side gets the normal, PM side gets the Taylor’s single engine dp. If the engine fails it’s one of the PM’s duties to switch nav sources for the PF.


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So basically, theres a number of ways to skin that cat. We didn’t try splitting the boxes. the primary procedure we’re concerned about at our home airport the only way to make the numbers work for a max gross takeoff is an RNAV escape procedure. However, the all-engine DP for that runway starts with a heading direct to a waypoint. So what we did in the sim is, we loaded the escape procedure before the normal DP. then if you get a V1 cut, you’re all set up to just fly. If you don’t, the PM spins the heading bug to the initial heading for normal procedure, then direct to the first waypoint
in the normal procedure and away you go. Not sure if thats what we’ll end up doing in the plane or not.

The hilarious thing is, the escape procedure is an echo of the AS proprietary RNP departure.
 
if you need an alternate single engine departure route, how do you set that up? split FMS 1 and 2 and have the alternate procedure loaded in the non-flying pilots side? The “FMS” in the PC-12 let’s you load a secondary flight plan and switch to it quickly but I don’t see that functionality anywhere in the UNS.
This is exactly what I do using dual FMS when utilizing an APG designed Emer Procedure departure. With the G3000, I plug it into Stby Flt Plan; 6-7 button push and you’re moving right along….

EDIT: corrected my terrible spelling
 
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So basically, theres a number of ways to skin that cat. We didn’t try splitting the boxes. the primary procedure we’re concerned about at our home airport the only way to make the numbers work for a max gross takeoff is an RNAV escape procedure. However, the all-engine DP for that runway starts with a heading direct to a waypoint. So what we did in the sim is, we loaded the escape procedure before the normal DP. then if you get a V1 cut, you’re all set up to just fly. If you don’t, the PM spins the heading bug to the initial heading for normal procedure, then direct to the first waypoint
in the normal procedure and away you go. Not sure if thats what we’ll end up doing in the plane or not.

The hilarious thing is, the escape procedure is an echo of the AS proprietary RNP departure.

The big thing is simply finding what works for your operation, and being ready to implement it.

The other challenge with the UNS is the escape for a balked landing/engine failure.

For a long time APG was sending us the OEI departure when we requested landing numbers. For a long time people didn’t understand why.

Turns out it was for a balled landing as the weights didn’t allow for a normal missed.


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@TUCKnTRUCK @SteveC and anyone else with familiarity with the UNS-1….any idea why the vnav sometimes won’t allow you to set a negative offset from a vnav waypoint?
Are you talking about putting a point in front of a point; i.e. descend to reach FLXXX 10 miles before WAYPT? Is that what you’re referring to?

If so, there’s probably a point in between you and that 10 miles before the fix. There’s WPONT and then within 10 miles is WAYPT.

Does that make sense? Is that what you’re talking about?
 
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