507Roxy

FMC FIX Page Long/Lat

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Hi,

 

Not sure whether it is a typo or intentional but you're writting "N3039.4 W14225.6" with a space between the latitude and the longitude. If you type the space in the CDU, it won't work. 

If you didn't, try entering N3039.4W14225.6 (without space).

 

Another reference is the FCOM page 11.31.16

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No Boeing FMS FIX Page will accept a LATLON in the FULL Format.

 

VALID ENTRIES into the FIX Page at LSK 1L are an ARPT (4 letter ICAO identifier) if in the Navigation Database, A NAVAID (3 letter published identifier in the IAP) if in the Navigation Database & WAYPOINTS if in the Navigation Database.

 

LATLONS that have been coded as WPTs into a series of 5 numbers & a letter will be accepted if they are in the Navigation Database.

 

In any case with reference to ETPs (which is what I suspect you are attempting to achieve) you are really interpreting the use of the B744 FIX Page incorrectly.

 

Have a look at this suggestion .... disclaimer ... I am not a 'unicorn' i.e. I am not an 'aviator', whether in the real or virtual sense nor am I connected to any real or virtual airline.

 

http://www.avsim.com/topic/505016-no-equal-time-point-option-in-the-cdu/

 

Enjoy.

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Curious, I thought I have already entered full lat/long waypoints in the fix page for ETPs in the PMDG T7 but I may be wrong.

I'll check that again in my next flight with either the T7 or 744.

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Romain, the 777 is a different beast and will accept lat/lon on a fix page.  Neither NGX nor 747 can do this.

Also ETP should not be entered in LEGS.

 

The fix I got from a 737 driver is to add desired latlon or waypoint fixes after your missed approach segments by first entering any fix in the last position, doesn't matter, then enter your desired fixes after that. Now go back and delete the first entry leaving a discontinuity.  Now the fixes will appear on the ND but will not be reported as a flightplan waypoint.

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Romain, the 777 is a different beast and will accept lat/lon on a fix page.

That's why I could! 

 

I had a doubt because Steve said:

 

 

 

No Boeing FMS FIX Page will accept a LATLON in the FULL Format.

 

I guess he means no 744 FMS...

I knew for the NGX but I didn't try with the 744.

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Yes my bad, I did mean to say Boeing 744.

 

Dan raises some valid points ... here are some others ...

 

One point of caution here, the B744 first flew in the late 1980s.  The FMS architecture inside the 737NG & is actually much more refined & advanced than that inside any B744 flying today, the B737NG is capable of performing approaches without the use of ground based navigational aids to a far higher degree of accuracy than the B744.

 

Its not as simple as comparing like for like.  The same goes for the B777.

 

Once airborne the ETP concept becomes dynamic; other factors such as changing weather, wind & human factors like ATC re-routings can come into play.

 

Thats why all ETP planning relies on an EET or estimated en route time to the ETP.  This time is calculated from your TOT - take off time.

 

Entering LATLONS after DISCOs at the end of RTE 1 or 2 is fine, just fine.

 

Some operators demand it as an SOP.

 

What I am suggesting is the use of a little known but very useful feature that is on EVERY Boeing FMS FIX Page.  By doing some simple MATHEMATICS from your TOT you end up with an ETA overhead your ETP, this will always be visible on your ACT RTE, it will not interfere with your ACT RTE & the margin for 'finger error' is very small.

 

Thats why lots of operators demand it as SOP.

 

On a dark night over the Pacific when you have an emergency decompression forcing you down to F140 or below into the soup & the suddenly ENG 4 goes kaput the last thing you want to be doing is pissing about with RTE 1 or 2 with several random LATLONs & DISCOs in the way.

 

You have your 2 ALTNs on your FIX Pages & 1 or 2 green circles & ETAs in ZULU on the ND, the decision to press on or go back is really that simple because hours before the dispatcher did the hard yards & once airborne he spoke to you to confirm the plan still stood via ACARS,

 

When the pressure is on you want it to be that simple .... your brain is rapidly running out of zeroes & ones & you have a stack of EICAS Warnings & Cautions to process, there are alarms & bells going off & company on ACARs has just gone ballistic & the Purser is dinging you & you must don your emergency life support NOW to save your aircraft, your life & everybody else.   Is the integrity of the aircraft at risk?  Can you descend rapidly?  Should you descend slowly?

 

Which way to turn?

 

Ahh yes the ND ....

 

Now you press HDG SEL & off you go.

 

Why worry about punching LATLONS in the first place?  Some simple maths ... done by the PNF once settled in the climb above F100 & you have your ETAs to your ETPs, they are based on time & entered by a few keystrokes to be presented in a very easily decipherable format for you to decode hours later.

 

Just a point of view.

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Why worry about punching LATLONS in the first place? Some simple maths ... done by the PNF once settled in the climb above F100 & you have your ETAs to your ETPs, they are based on time & entered by a few keystrokes to be presented in a very easily decipherable format for you to decode hours later.

 

Sounds good. I've been struggling with ETOPS/LROPS ever since I started testing the B744... I understand that the rules for two engines do not apply but it is still necessary to have enroute alternates so I'm stuck at trying to figure out how to set up PFPX to give me those enroute alternates and the ETPs associated with them.  I read that operators usually have 180 min alternates, but how then do you get from Australia to either Chili or So Africa such as Qantas does?  The Chili route can be done with a 330 min alternate using Easter Island but the Southern Indian Ocean is past nowhere.

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The Chili route can be done with a 330 min alternate using Easter Island but the Southern Indian Ocean is past nowhere.

 

I flew the YSSY-FAOR route the other day, copied the flight plan from Qantas on Flightaware, and was wondering the same thing.  There are a few islands out there but AFAIK no airports at all.  Haven't tried it yet, but wouldn't even a single engine failure mid-way between the two airports cause real problems?

 

Mike

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I didn't go through the whole reading to check if it answer the question though.

 

The first was 777 related, the second one BINGO. Thanks Romain.

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Romain, the 777 is a different beast and will accept lat/lon on a fix page.  Neither NGX nor 747 can do this.

Also ETP should not be entered in LEGS.

 

The fix I got from a 737 driver is to add desired latlon or waypoint fixes after your missed approach segments by first entering any fix in the last position, doesn't matter, then enter your desired fixes after that. Now go back and delete the first entry leaving a discontinuity.  Now the fixes will appear on the ND but will not be reported as a flightplan waypoint.

Yes but if you can enter  them on the T7's fix  page (which you  can I do it all the time) same should hold for the NGX or 747 you would think  because a boeing is a boeing but I guess not.

 

 

Robbie

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