-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


Okay.. KLAX LOOP4.DAG.KEPEC1 KLAS at FL290? I'll actually give an
objective tutorial on this, as it's in the sector I'm affiliated with
and do most of my time in. Also as I am doing this objectively, anyone
else who would like to objectively chime in, please do so.

Look CLOSELY at those charts, and I mean closely. There are
some things you will need to adhere to that your FMS may or may not
know about that is not depicted totally in words.

CAVEAT. the charts I'll list are not to be used for real world
flight.

LOOP4: http://www.laartcc.org/charts/DP-LOOP.pdf

KEPEC1: http://www.laartcc.org/arrivals/STAR-KEPEC.pdf

KLAS ILS 25L: http://www.laartcc.org/charts/KLAS-I25L.pdf

I suggest looking at the KEPEC1 first before the LOOP4. Yes,
it's the arrival and you haven't even departed yet, but you are in the
flight planning stage at this moment, and there is something important
that needs to be learned. The KEPEC1 arrival is an RNAV procedure,
requiring RNAV-capable equipment. Aircraft that are /E, /F, /G, and /R
are RNAV capable. If said aircraft is RVSM capable, then the following
suffixes apply: /J, /K, /L, /Q (FAAO 7110.65, 2-3-7). If your aircraft
is not one of then your flight plan will be rejected because you can
not use the KEPEC1 arrival.

LOOP4. If your aircraft is not capable of climbing at 500ft per
nautical mile to 10000, you're using the wrong SID. LOOP4 requires it.

I'm going to assume that you a) have RNAV and RVSM capable
equipment onboard and your aircraft is able to meet the climbing
requirement, and that you are familiar with ATC in the terminal area.
You've received your clearance, and will be cruising at FL290. Great.
ATC clears you to takeoff on 24L. You best look at the LOOP4 chart
again, as you have 2 crossing restrictions you must meet. You must
cross the SMO R-160 at or below 3000ft. From there, you should get
vectors back to LAX with something being told to you like:

"Turn left direct Los Angeles, resume the LOOP4 departure,
comply with all restrictions, climb and maintain 15000".

You do exactly that. Your restrictions are to cross LAX at or
above 10000, KEGGS at or above 13000, and COOPP at or above 15000.
Sometime at that point you'll be handed to the Center controller who
will climb you to your cruise altitude. That ends the use of LOOP4
unless you end up NORDO for some reason.

Now, you're en route, and you're ready for the arrival. You're
still at FL290. Staying that high until your FMS starts to descend is
really going to increase your descent rate, as well as try its hardest
to maintain a slow speed for your descent. Not good. Also, the DAG/HEC
corridor is one of the busiest streams in US Airspace. Just about every
arrival into the LA Basin passes in that corridor, and all
northeastbound flights leave the basin through that corridor. You may
have a flight which ATC has positively separated you from, laterally
and vertically. It is best to let them control your descent instead of
asking.

ATC should tell you something like the following:

"Cross MISEN at and maintain FL240".

If you look at KEPEC1, you have a segment there where you have
a crossing restriction at MISEN of FL240 or higher. The closer you are
to that, the easier your descent will be for your next crossing
restriction, which is CLARR. ATC will tell you this:

"Cross CLARR at and maintain 13000 and 250kts. Las Vegas
altimeter xx.xx".

From here, you'll be descending and reducing speed for the
arrival, and must hit CLARR at that altitude and speed. From there, the
arrival tells you everything you need to do. Should ATC have you
execute the full arrival, they will tell you something like:

"Descend via the KEPEC1 arrival".

That's it. From there, you're crossing KEPEC below 13000 and
above 12000, IPUMY below 12000 and above 1000, NIPZO above 9000 and
below 1000, SUNST at 8000 and 210kts, KIMME at 210kts, CHIPZ at 170kts.

Look now at the ILS 25L chart. You'll notice that the altitude
you're at by the time you hit PRINO is the same altitude you should be
at for executing the ILS approach from PRINO. So ATC should only have
to tell you:

"After PRINO, cleared ILS 25L approach".

No PTAC is needed, as the RNAV arrival drops you off directly
on the IAF for the approach. From there, follow the chart down. 8000 or
above at PRINO, 6500 or above at LARRE, 4900 or above at SHAND, 3800 or
above at RELIN.

In short, like everyone else has mentioned, just because your
FMS thinks it's okay to descend, doesn't mean that it's kosher with ATC
for you to descend. They may have other things impending your descent.
When in doubt, ask. The worst you'll get back is 'no', and a reason for
why you can't at that time.

BL.
- - --
Brad Littlejohn | Email:
Unix Systems Administrator, |
Web + NewsMaster, BOFH.. Smeghead! | http://www.wizard.com/~tyketto
PGP: 1024D/E319F0BF 6980 AAD6 7329 E9E6 D569 F620 C819 199A E319 F0BF

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.6 (GNU/Linux)

iD8DBQFFnCBXyBkZmuMZ8L8RAnh7AKDKuOLSIDNqR14KTgvPcQ xjTmg+0gCfT7n6
cnVQ34bLprbBOctBe7NLTL8=
=zQYN
-----END PGP SIGNATURE-----