No requirement to modify the normal course of the flight if the weather degrades?
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No requirement to modify the normal course of the flight if the weather degrades?
Could someone please explain why "No requirement to modify the normal course of the flight if the weather degrades below normal minima" after EEP in ETOPS?
Really, don't get this since, before EEP, we still keep checking all the weather at all the designated ERA and suddenly after EEP we disregard them. Any reason behind this.
I really appreciate it.
Really, don't get this since, before EEP, we still keep checking all the weather at all the designated ERA and suddenly after EEP we disregard them. Any reason behind this.
I really appreciate it.
Where is this stipulation? I did a word search of my manuals, and checklists, (which might be out of date), and did not find it.
We continued checking weather while in the ETOPS/EDTO segment, and if an ERA went out, a re-route might be required.
We continued checking weather while in the ETOPS/EDTO segment, and if an ERA went out, a re-route might be required.
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It would help if you state the regulations you're operating under. Generally speaking these requirements are based on risk assessment. What is the risk of the forecast being above suitable dispatch criteria and then going below OPERATIONAL minima (which are usually lower), just after you passed the EEP?
You don't disregard them. As crew you still monitor them. But once past your EEP, and an ERA unexpectedly goes below landing minima, you may continue as planned (although company policy may suggest otherwise).
At the end of the day EDTO / ETOPS is all about statistics.
There is a measurable statistic about the chance of an engine failure when past the EEP. (looking at historic type data)
There is also a measurable statistic of weather at an ERA unexpectedly falling below the minima when it has a buffer on it. (historic weather data).
Multiply the two together and you have a vanishingly small number (risk) that is deemed acceptable for commercial operations.
At the end of the day EDTO / ETOPS is all about statistics.
There is a measurable statistic about the chance of an engine failure when past the EEP. (looking at historic type data)
There is also a measurable statistic of weather at an ERA unexpectedly falling below the minima when it has a buffer on it. (historic weather data).
Multiply the two together and you have a vanishingly small number (risk) that is deemed acceptable for commercial operations.
Our OM A says to consider a re-route should an ETOPS ERA fall below operational minima; note “consider” and, depending on circumstances, it may not be possible to do this. As others have said, it’s a probability thing, much like going below critical fuel for a bit near an ETP: you didn’t plan for it, but on the balance of probabilities, you are very unlikely to have a decompression along with an engine failure in that short window, and there are things you can do in extremis to avoid running dry before you get to an alternate should the worst happen...
Lets not forget that ETOPs is purely a planning tool so once past you EEP there is no requirement to divert if the weather goes below minima as at its most basic form you may not have the fuel to go anywhere but you destination or nominated alternate should an engine fail or depressurisation occur. It doesn't mean you 'shouldn't' divert if the weather drops below minima and you have enough gas on to consider other options. Of course you keep updating the weather to keep an eye on what is happening.
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You don't disregard them. As crew you still monitor them. But once past your EEP, and an ERA unexpectedly goes below landing minima, you may continue as planned (although company policy may suggest otherwise).
At the end of the day EDTO / ETOPS is all about statistics.
There is a measurable statistic about the chance of an engine failure when past the EEP. (looking at historic type data)
There is also a measurable statistic of weather at an ERA unexpectedly falling below the minima when it has a buffer on it. (historic weather data).
Multiply the two together and you have a vanishingly small number (risk) that is deemed acceptable for commercial operations.
At the end of the day EDTO / ETOPS is all about statistics.
There is a measurable statistic about the chance of an engine failure when past the EEP. (looking at historic type data)
There is also a measurable statistic of weather at an ERA unexpectedly falling below the minima when it has a buffer on it. (historic weather data).
Multiply the two together and you have a vanishingly small number (risk) that is deemed acceptable for commercial operations.
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Lets not forget that ETOPs is purely a planning tool so once past you EEP there is no requirement to divert if the weather goes below minima as at its most basic form you may not have the fuel to go anywhere but you destination or nominated alternate should an engine fail or depressurisation occur. It doesn't mean you 'shouldn't' divert if the weather drops below minima and you have enough gas on to consider other options. Of course you keep updating the weather to keep an eye on what is happening.
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I think I got this from Get into grip with ETOPS from Airbus.
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ETOP’s is a pre flight planning ruleset.
in flight prior to EEP you must check weathers all ok for en route airports. Once past EEP, no change to routing required if enroute alternate goes bad. Why?
Because you are not going to enroute alternate. You are going to destination! Enroute alternate is just in case.
in flight prior to EEP you must check weathers all ok for en route airports. Once past EEP, no change to routing required if enroute alternate goes bad. Why?
Because you are not going to enroute alternate. You are going to destination! Enroute alternate is just in case.
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ETOP’s is a pre flight planning ruleset.
in flight prior to EEP you must check weathers all ok for en route airports. Once past EEP, no change to routing required if enroute alternate goes bad. Why?
Because you are not going to enroute alternate. You are going to destination! Enroute alternate is just in case.
in flight prior to EEP you must check weathers all ok for en route airports. Once past EEP, no change to routing required if enroute alternate goes bad. Why?
Because you are not going to enroute alternate. You are going to destination! Enroute alternate is just in case.
Yes. When you experience multiple unlikely failures the rule book goes out of the window. Difficult to plan for, if you need to go a long way down a chain of “what if?” to get there.
Bear in mind why we use approach minima, which is to give a very high probability, close to certainty, that you’re not going to hit anything at minimums given all of the worst-case inaccuracies in systems performance. If the alternative is crashing/ditching, then substantially reducing those minima or keeping going until you see something is a valid option, especially on a precision approach or RNAV/GPS based one. Yes, you wouldn’t want to do this as a normal procedure, as statistics will eventually catch up with you, but as a one-off in extremis, it’s probably not as risk-bearing as you might envisage.
Bear in mind why we use approach minima, which is to give a very high probability, close to certainty, that you’re not going to hit anything at minimums given all of the worst-case inaccuracies in systems performance. If the alternative is crashing/ditching, then substantially reducing those minima or keeping going until you see something is a valid option, especially on a precision approach or RNAV/GPS based one. Yes, you wouldn’t want to do this as a normal procedure, as statistics will eventually catch up with you, but as a one-off in extremis, it’s probably not as risk-bearing as you might envisage.
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ETOP’s is a pre flight planning ruleset.
in flight prior to EEP you must check weathers all ok for en route airports. Once past EEP, no change to routing required if enroute alternate goes bad. Why?
Because you are not going to enroute alternate. You are going to destination! Enroute alternate is just in case.
in flight prior to EEP you must check weathers all ok for en route airports. Once past EEP, no change to routing required if enroute alternate goes bad. Why?
Because you are not going to enroute alternate. You are going to destination! Enroute alternate is just in case.
so why 'EEP'???
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In low vis ops, above 1000’RA if RVR drops below minima you can’t make the approach…an approach ban.
Below 1000’ RA if the reported RVR drops below minima you can continue the approach.
WHY?
Because those are the rules. A line in the sand!
Same with ETOPS…or whatever they call it now.Past the 60 minutes out point from an airport you are at the EEP and away we go…new rules.
Below 1000’ RA if the reported RVR drops below minima you can continue the approach.
WHY?
Because those are the rules. A line in the sand!
Same with ETOPS…or whatever they call it now.Past the 60 minutes out point from an airport you are at the EEP and away we go…new rules.
