Using FMS for departures with a localizer

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pstan

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Stan
Can anyone fill me in on whether a certified FMS (lets say non waas capable) is able to fly a departure that involves a localizer?

For example, the SARDD 3 departure from Aspen, KASE. The chart shows a heading to intercept a back course. Does an FMS fly this using (mostly) GPS inputs?

Or does the FMS actually display the localizer vice an FMS track?

Any references?

thanks, Stan
 
They are two different things for us. FMS nav is just flying waypoints (Blue needles). When it gets down to it they are all coded Lat/Long positions. if we want to fly it in raw data off the LOC (Green needle) that can be done too. however they are two entirely different platforms.
 
I've seen references to that kind of departure in Part 121 gear. I posted a similar question a while back too. I really never got a complete explanation.
 
Your FMS documentation in the AFM should give you the answer...the only applicable limitation in the FMS I work with is that the FMS can't be used for localizer-based approaches. Since my FMS is authorized for departures, the LOC-based segments can be flown using FMS.
 
pstan said:
For example, the SARDD 3 departure from Aspen, KASE. The chart shows a heading to intercept a back course.
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Going from memory, is it really a back course?

Looked it up...it's a back course that is flown outbound so no reverse sensing.
 
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pstan said:
Can anyone fill me in on whether a certified FMS (lets say non waas capable) is able to fly a departure that involves a localizer?

For example, the SARDD 3 departure from Aspen, KASE. The chart shows a heading to intercept a back course. Does an FMS fly this using (mostly) GPS inputs?

Or does the FMS actually display the localizer vice an FMS track?

Any references?

thanks, Stan
Click to expand...

The reason the localizer is there because the FAA wanted positive course guidance because of the high mountains not too far beyond that track. The protected airspace is standard for a departure procedure. It is not narrow like ILS or LOC protected airspace. So, flying it with LNAV in terminal mode is legal and safe. I don't believe any FMS would switch from LNAV to LOC. If you want a reference you'll have to ask the particular FMS tech support that interests you.
 
aterpster said:
The protected airspace is standard for a departure procedure. It is not narrow like ILS or LOC protected airspace. So, flying it with LNAV in terminal mode is legal and safe.
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Thanks aterpster, that clarifies departure procedures.

Would the same be true for a missed approach that involves tracking a localizer?

For example, KBFI Boeing field, the ILS 13 R has missed approach as "climb on I-BFI SE course to cross OCEZE...."

Would it be legal and safe on the missed approach to use LNAV in terminal mode vice the raw data localizer?

Pstan

 
pstan said:
Thanks aterpster, that clarifies departure procedures.

Would the same be true for a missed approach that involves tracking a localizer?

For example, KBFI Boeing field, the ILS 13 R has missed approach as "climb on I-BFI SE course to cross OCEZE...."

Would it be legal and safe on the missed approach to use LNAV in terminal mode vice the raw data localizer?

Pstan
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Sure would so long as LNAV is in terminal mode. They used the LOC because they need positive course guidance rather than a heading because of the congested nature of that airspace. They can't use LNAV in the procedure design of an ILS. Although there are some "Z" ILS approaches now with RNAV TAAs for transition onto the ILS.
 
aterpster said:
Sure would so long as LNAV is in terminal mode. They used the LOC because they need positive course guidance rather than a heading because of the congested nature of that airspace.
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Maybe. But the standard "Kent six" departure is just a heading, and it is used hundreds of times a day.

 
Excellent aterpster, thanks for your clear answers.

You should write some more articles!!!

Stan
 
pstan said:
Excellent aterpster, thanks for your clear answers.

You should write some more articles!!!

Stan
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I've always assume that aterpster is really, a TERPSter - as in somebody who works for the FAA and is actively involved with the Standard for Terminal Instrument Procedures (TERPS). Is true?
 
pstan said:
Excellent aterpster, thanks for your clear answers.

You should write some more articles!!!

Stan
Click to expand...

I've always assumed, based on his username, that aterpster is really a TERPSter - as in somebody who works for the FAA and is actively involved with the Standard for Terminal Instrument Procedures (TERPS).

Is true?
 
kgruber said:
Not this one, other than it starts 3000 ft later.
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That isn't the point. The criteria are different and the TRACON has a far tighter grip on departures off of BFI than they do the ILS missed approach.

The former is an airplane on the ground until they release it.
 
aterpster said:
That isn't the point. The criteria are different and the TRACON has a far tighter grip on departures off of BFI than they do the ILS missed approach.

The former is an airplane on the ground until they release it.
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The missed and Kent 6 departure ideally have the same departure corridor.

The tighter grip is on the missed tracking a localizer. No chance in drifting west into SEA. (without pilot error)

The looser grip is the Kent 6 departure, a runway heading, that can and often does get pushed by the east wind toward Seattle's airspace. When that happens I've heard tower get upset with the pilot who is properly following the runway heading precisely.
 
if you can load it from an FMS you can fly it , perfect example LGA.4 from New York. The departure and its infamous climbs can be flown with headings and Referenced VORs or sourced to FMS. Many "vectors" departures can also be loaded and flown from the FMS..it simply flies a heading ( actually it tracks a course) but your sourced to FMS and "NAV" mode not HDG
 

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kgruber said:
The looser grip is the Kent 6 departure, a runway heading, that can and often does get pushed by the east wind toward Seattle's airspace. When that happens I've heard tower get upset with the pilot who is properly following the runway heading precisely.
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They must have been listening in here, because the new KENT SEVEN departure tracks the BC localizer. No more being blown into Seatacs airspace.....like the case for the last 40 years.
 
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