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waypoint5944
19th Sep 2001, 13:59
Hi!
I have some questions on the Jeppesen and 744 fms.
Somebody help me.
Q1> On the non-precision app(straight in) charts in US, they have words like "Only authorized operators may use VNAV DA(H) in lieu of MDA(H).". What does this mean?

Q2> Some non-precision approaches don't exist on the FMS database even though they are on the Jeppesen. What is the reason?
Is it because of the size of the of FMS database or accuracy problem of navaids?

Q3>In this case, may we fly the PDB points which are manually entered with alt constraints ,with LNAV (and VNAV)?

Q4>Shouldn't we fly the non-preci app on VNAV if FMS does't have the rwy point for that app?

Q5>WX is CAVOK. You fly the JFK "VOR DME 13L app". There is no Rwy point on the FMS legs page. MDA is 800feet. Fms legs page has 1220feet for MAP which is 3 degree height from 3.6 mile rwy threshold. What altitude will you fly for that app on MAP?
What about the IMC? I think it is very difficult to stabilize heavy 744 in a short time of 800'(700 agl)level flight to 500'agl(company stabilization altitude).

Q6>LAX VOR RWY 25L/R APP
In the landing minima section,MDA FOR 25L "without noele" is 620feet. MDA FOR 25L " with noele" is 580feet.
If FMS leg page doesn't have "noele" between FREBY and MAMMA(MAP), is it O.K. to fly that app to MDA 580' "with noele" manually entered waypoint with alt constraint /620 ?

Q7>Jeppesen charts provide DPA(descent path angle) for most of non-prec app in U.S..
But they don't for Honolulu. Is there any reason?

Q8> Who provide FMA DATABASE for 744?
Does Jeppesen also provide for FMA DATABASE?

I need your help.
Thank you gentlemen. :D

yellow dust
23rd Sep 2001, 21:58
Waypoint, some of these questions are too tough for us! Certainly for me. But here's a try at some of them, it might at least get others to come in and tell me I'm full of it.

2/3. No NDBs are in the data base (they used to be but were taken out five years ago or so) You can manually build an approach, or you can use one with the same ground track (ILS perhaps) and modify it to suit. You can then fly LNAV/VNAV (If your company allows), provided you back it up during the approach by displaying raw data on at least one side of the cockpit.
4. FMS usually has a point one mile from the runway for a non-precision approach, and the altitude equivalent to a normal glide path at this point. It has a label which I can't remember and have not got my manuals to check it, but you will see it when you select a non-prec approach from the data base. It is usually below the MDA, and is handy for vertical track guidance on the ND when you make the last, visual part of the approach. The auto pilot can follow it, but you may not use auto pilot below a point 100 feet lower than the MDA on a non-prec approach. However the vert track display on the ND will show the profile, even if the Missed Approach alt is set in the window.
5. The runway 13L VOR at JFK is flown on a normal profile, descending to 800 feet after the VOR and maintaining that until intercepting the normal descent path to the runway, visually. There is a warning on the chart not to descend too early due to noise abatement. Follow the lights, don't cut the corner, and about half way round the turn (at the second set of lead in lights) you will see the VASIS which is set for a turning approach (if you can see it you can use it). A little anticipation (speed correct, config set, start the power back as the correct glide path is approaching rather than after it is past) and it is a doddle. Aim to be on final track, aligned with the runway, outside one mile. Avoid crossing the threshold while still turning. Just like a visual circuit and a lot of fun, especially with a crosswind (which ATC will always dial in for you). The ILS is never turned on, so don't count on it for guidance. In fact it is best to have it turned off in your NAV page, due to false GPWS warnings on final. When the wind is coming from the north east at more than 20 knots it can give a lot of low level turbulence. The runway is long enough, but go for precision on the touch down, you don't want to float. Most pilots go for a turn off before ZZ so a higher than normal auto brake is a good idea.
For 13R, you simply continue the descent from minima and do not level at 800 feet, and make a continuous turn to final. Very easy.
6. You can use the lower minima for the VOR 25 at LAX if you can identify the point NOELE (4DME or 114RSMO). It does not have to be in the data base. If you are flying with auto pilot then you need to set it in as a waypoint, but with any non-precision approach you are actually using the raw data for deciding when you are at NOELE. In practice, so long as the LNAV/VNAV agree with the raw data, follow the flight director. The non-flying pilot should have raw data displayed and he will call if there is a significant deviation.
Phew.

Budgie69
25th Sep 2001, 04:02
Q2 - I suspect database size.
Q3/4 - Beware map shift - raw data is more reliable.
Q5 - VOR 13L JFK. You GENERALLY only get this approach in reasonable vis/cloudbase. In these conditions I found it easier to fly a very gradual descent 3-400fpm from the VOR until on the VASIs. Anyway the easiest way of all is to look out the window, follow the shoreline initially and enjoy FLYING the AEROPLANE. If you find yourself working too hard get your other half to be a "talking VSI".
Good luck with your course!