ETP
Joined: Aug 1998
Aviation Qualifications: ATPL
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From: Ex-pat Aussie in the UK
http://www.pprune.org/tech-log/9934-pnr-usage.html
Thread where I explain some manual calculation methods & shortcuts for ETPs & PNRs in the cockpit.
http://www.pprune.org/tech-log/10820...lculation.html
Thread were Flat Side Up explains an excellent method for PNR calculation which has one slide rule set up which displays Time, Distance and Fuel Burn.
Thread where I explain some manual calculation methods & shortcuts for ETPs & PNRs in the cockpit.
http://www.pprune.org/tech-log/10820...lculation.html
Thread were Flat Side Up explains an excellent method for PNR calculation which has one slide rule set up which displays Time, Distance and Fuel Burn.
Joined: Nov 2001
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From: Inside the M25
On the version of the Airbus FMGC that we are using at the moment, you can work out an ETP for any two points. The default ETP is from departure to destination, and it draws a nice circle there. But you can replace the departure and destination in the relevant page on the MCDU with any positions (not just waypoints) you choose, and it will redraw your circle.
This is most useful for ETOPS, or ETOPS-like operations (the only time I really ever bother is to work out where the nearest usable airfield is on a long over-water sector - not for single engine work, but for NO engine consideration, I want to be as close to the possibility of rescue as possible). Yes, it's a bit arbitrary - but then, so, really is the idea of having an engine failure between V1 and V2, or the net flight path.
This is most useful for ETOPS, or ETOPS-like operations (the only time I really ever bother is to work out where the nearest usable airfield is on a long over-water sector - not for single engine work, but for NO engine consideration, I want to be as close to the possibility of rescue as possible). Yes, it's a bit arbitrary - but then, so, really is the idea of having an engine failure between V1 and V2, or the net flight path.
Joined: Jan 2006
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From: US
SOP - not allowed to build fixes into, or alter, Rte 1.
Solution(technique) - Rte Copy Rte 1, build ETP's as along track fixes on Rte 2, display Rte 2.
Fix page - enter /511 to display circles around divert fields. Helps with visual situation awareness.
Another technique - On Rte 2 build a route from #1 divert field, to ETP #1, to divert field #2, to ETP #2, to final divert field. Display Rte 2. You end up with blue lines (Rte 2 not executed) showing the divert sectors.
Another technique - ETP is X miles short of 30W? Enter fix or lat/long, if able, into Fix page and put a circle X miles around the fix.
Another technique - Enter ETP time in 6R of Fix page.
Solution(technique) - Rte Copy Rte 1, build ETP's as along track fixes on Rte 2, display Rte 2.
Fix page - enter /511 to display circles around divert fields. Helps with visual situation awareness.
Another technique - On Rte 2 build a route from #1 divert field, to ETP #1, to divert field #2, to ETP #2, to final divert field. Display Rte 2. You end up with blue lines (Rte 2 not executed) showing the divert sectors.
Another technique - ETP is X miles short of 30W? Enter fix or lat/long, if able, into Fix page and put a circle X miles around the fix.
Another technique - Enter ETP time in 6R of Fix page.
Joined: Mar 2007
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From: USofA
Well I might be reading something that has been lost in the translation but I would never put an ETP on the LEGS so as to cause the FMC to look at that LAT/LONG as an active waypoint. Bad procedure and if you are using ADS-C I would expect a call from the controller asking where you might be going? If that waypoint was not a part of your ICAO flight plan, then it should not find it's way onto the LEGS page.
Joined: Oct 2006
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From: Ankh Morpork, DW
Well I might be reading something that has been lost in the translation but I would never put an ETP on the LEGS so as to cause the FMC to look at that LAT/LONG as an active waypoint. Bad procedure and if you are using ADS-C I would expect a call from the controller asking where you might be going? If that waypoint was not a part of your ICAO flight plan, then it should not find it's way onto the LEGS page.
Joined: May 2001
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From: A few degrees South
Your ETP, etops entry and exit points are of course on your flight routing, not interfering with your routing. If a controller asks you what you are doing, you are probably in radar contact. I have to see the first Etops Entry point where you are still under radar coverage.
Joined: Oct 2006
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From: Ankh Morpork, DW
Your ETP, etops entry and exit points are of course on your flight routing
Joined: Mar 2007
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From: USofA
ADS-C for all intent and purposes is even better than "Radar Contact" in this case. The controller, Shanwick for instance, can see what Lat Long your FMC is going to. If it's not part of your ICAO flight plan then you are doing something wrong. ETP's & EEP's do not belong on the LEGS page of the FMC....period!
Joined: Jan 2007
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From: Up North UK
More mundanely, but more important for those of us that do not zoom around in spaceships, ETP is potentially a lifesaver for -
- Aircraft without drop-down oxygen for pax when transiting an MSA above FL140;
- When the OEI service ceiling is such that you would need to know the shortest/quickest track to a lower MSA (Drift-down).
- Aircraft without drop-down oxygen for pax when transiting an MSA above FL140;
- When the OEI service ceiling is such that you would need to know the shortest/quickest track to a lower MSA (Drift-down).
Joined: Nov 2001
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From: Inside the M25
Um ... hadn't considered that about active waypoints, and can't remember offhand how exactly it behaves. However, I'm not convinced that an FMGC derived position - can think also of a time marker, TOD or step-climb marker - would actually show as the next active waypoint on ADS-C.
And isn't part of the point about MNPS airspace (which is when ETP is most useful) that you don't have radar monitoring?
I have to say that I have very limited experience here, so these are genuine questions.
And isn't part of the point about MNPS airspace (which is when ETP is most useful) that you don't have radar monitoring?
I have to say that I have very limited experience here, so these are genuine questions.
Joined: May 2001
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From: A few degrees South
Spooky, how and when you perform mandatory ETOPS checks? By monitoring the IRS displays? And what about the abeam points you want to have displayed when cleared "direct to"? The FMC is a tool and competent pilots use it as such.
The Enty, ETP`s and Exit points are in some companies mandatory inserting points, ie it is a SOP to insert them.
The Enty, ETP`s and Exit points are in some companies mandatory inserting points, ie it is a SOP to insert them.
Joined: Dec 2002
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From: Where the Quaboag River flows, USA
With a triple FMS installation, we enter the ETPs in the unpaired FMS, the PM can display the ETPs on his ND or monitor #3 FMS for position.
I'm trying to figure out how you can enter ETPs, as waypoints, when they are NOT on cleared routing. Yes, they along track, but still not points on the LEGS page.
GF
I'm trying to figure out how you can enter ETPs, as waypoints, when they are NOT on cleared routing. Yes, they along track, but still not points on the LEGS page.
GF
Joined: Feb 2007
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From: Sandpit
ETOPS wise...
We don't insert them in the Primary flight plan. Several options for displaying them once you've entered them as a pilot waypoint though. Secondary FP (Diversion planned from an ETP set up there anyway). Pressing the WPT button on your EFIS control or using the L1 key on the MCDU and entering the most relevant points as a REF FIX. Airbus stuff.
Different strokes different folks though I guess.
ETP on normal flights - Airbus makes it quite easy to display an FMGC created ETP on your route for any two points. I'm rather new so find it a useful tool when adhering to SOP's and giving the occasional "if the proverbial hits the fan now this is where I'd go and after that here" brief. But that's just me.
We don't insert them in the Primary flight plan. Several options for displaying them once you've entered them as a pilot waypoint though. Secondary FP (Diversion planned from an ETP set up there anyway). Pressing the WPT button on your EFIS control or using the L1 key on the MCDU and entering the most relevant points as a REF FIX. Airbus stuff.
Different strokes different folks though I guess.
ETP on normal flights - Airbus makes it quite easy to display an FMGC created ETP on your route for any two points. I'm rather new so find it a useful tool when adhering to SOP's and giving the occasional "if the proverbial hits the fan now this is where I'd go and after that here" brief. But that's just me.
Joined: Jan 2006
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From: US
GF - it appears from the discussion that some operators enter ETP's into their LEGS pages per their SOP's.
Our SOP prohibit changing the active RTE. RTE 2 is available and can be displayed without activating. That's where you can enter ETP's or other along track fixes.
Most guys just keep track of the ETP time and/or distance, and don't bother entering along track fixes. Technique.
Older generation Airbus FMC's did not have RTE 2 capability. Not sure if the newer Airbus FMC's have RTE 2 capability.
Our SOP prohibit changing the active RTE. RTE 2 is available and can be displayed without activating. That's where you can enter ETP's or other along track fixes.
Most guys just keep track of the ETP time and/or distance, and don't bother entering along track fixes. Technique.
Older generation Airbus FMC's did not have RTE 2 capability. Not sure if the newer Airbus FMC's have RTE 2 capability.
Last edited by misd-agin; 15th February 2012 at 18:06. Reason: additional text
Joined: Dec 2002
Aviation Qualifications: ATP+Mil
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From: Where the Quaboag River flows, USA
misd-agin
Oh, I understand that they can be put into the active flight plan, but why would you do so considering you would be flying to waypoints not as cleared. While, yes, they should be on the route.
GF
Oh, I understand that they can be put into the active flight plan, but why would you do so considering you would be flying to waypoints not as cleared. While, yes, they should be on the route.
GF
Joined: Feb 2001
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From: The Winchester
Does people's aversion to non-active-waypoints also cover abeam positions generated by the FMGC?
If abeams are needed the teaching is to display Route 2, the non-active route, on the Navigation Display (ND)- this of course assumes you've copied the original route into Route 2 in the first place
, or use the FMC fix pages and/or waypoint/station function on the ND.
Joined: Aug 2007
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From: canada
GF. To answer your question about entering an EEP or ETP on the legs page, of course you're right, you don't ever want one of them becoming the active wpt. If your equipment has limited capabilities, one way to do it is to put it at the end of your flight plan on the legs page after the destination and after a discontinuity. If "floats" there, and is visible on your nav display as you go by it, but never becomes the active wpt. It has no effect on your flight plan total dist. and fuel calc's. Used to do this on the B757 with it's basic FMC.
If your equipment is capable, then the fix page is the place to put them either as Lat. and Long. or with distance rings. (Usual B777 method).
If your equipment is capable, then the fix page is the place to put them either as Lat. and Long. or with distance rings. (Usual B777 method).