Alternates

This is an interesting discussion, especially since there are conflicting opinions on this. I think the question that needs to be asked is, why? What exactly are your fuel REQUIREMENTS enroute? Consider the following: You plan minimum fuel with an alternate, which gives you the destination+alternate+45 minutes. You get a reroute that adds 10 minutes to your route. What action, if any, do you need to take?

First one with the correct answer wins!

Ready, GO!


Nothing, that's what their contingency fuel is for.
 
Per the company FOM, after take off, all fuel on board becomes exactly that; FOB. In the event that some unanticipated enroute delays would increase potential burn, the dispatcher and crew are to re-evaluate the delay and determine if the delay would cause projected arrival fuel to be below the FOM specified emergency fuel (by aircraft type) at destination or (if required) the planned alternate. If it is anticipated that the arrival at destination or alternate will below the specified emergency fuel number, then other options will be considered, such as removing the alternate (wx permitting), recalculation based on actual payloads (in this case a cargo carrier, where weights are NEVER estimated), recalculation based on a slower speed, updated wind forecast, altitude change, etc; or stopping short to refuel.

In actual operational environment we run in, there's currently no real fuel conservation program, so we can plan addl fuel for our own comfort (or even to avoid phone calls) and plan flights at ludicrous speed by policy, so slowing down is often an option. There also tends to be an overestimation of payloads for planning by both the ground side and the dispatchers (again, phone call avoidance). Since I've been here, I can't remember ever hearing of an issue with the FOB for continuing.

There's a couple perks of working for a consistently lavishly profitable company... even if job security may not be one.

As far as earlier discussions, my interpretation is that within 6 hours of destination, should the destination weather be suitable, the removal of the altn is acceptable. At that point you're in a "redispatch" situation. It's not a "planned redispatch" per Ops Spec B44 since you're not planning for the situation at prior to departure, it is still a redispatch due to changing conditions while enroute. Again, a difference I've found at the box hauler is we often do enroute redispatches for company convenience or need (used to call them Flag stops to pick up extra volume or people as needed) that requires a whole rework of the flight plan. (BOS-STL with the the sudden need to re-route and stop in ATL fuel permitting) Pax carriers rarely do these stops these days, since it will generally incur more misconnects (and potential revenue loss) for pax on board than revenue gain for stopping to pick up stranded pax on the way to the hub. I'm told back in the day (ie pre-hub and spoke focus) it wasn't unheard of to do flag stops.

Such operations have the "blessing" of the administrator, and as I see it, nothing in the actual release can not be amended as long as the applicable regulations are met at the time of amending. However, experience has shown that different airlines and associated POI's seem to interpret the rules differently.
 
Nothing, that's what their contingency fuel is for.

This theoretical flight plan did not include contingency fuel, just required reserves and alternate fuel. According to the letter of the 121 rule the 45 minute domestic reserve is only a requirement for dispatch, but I wouldn't want to be the one arguing that in front of the FAA as the rules tend to be interpreted according to their convenience, not yours. Also, good luck convincing a Captain to land with less than his flight planned reserves.

or even to avoid phone calls

Absolutely, in fact I'm pretty sure it says somewhere in every carrier's FOM that one of our job duties is to cut down on the company's long distance phone call bill. You're just being a team player.
 
My interpretation would be that, if the original flight plan is longer than 6 hours and you want to drop the alternate, a redispatch would be required - whether planned or not - along with needing good weather at the destination, of course. As people have said, various POIs seem to interpret this rule differently, but I think it would take more than "here's my time and initials to drop the alternate" to make things legal. If there are less than 6 hours remaining and you redispatch the flight, though, you should be golden.
 
There is nothing wrong with dropping an alternate. As long as you have a new TAF that shows an improved forecast, it's legal.

A few of us had a discussion with our dispatch inspector and he stated it is perfectly legal as long as the new forecast doesn't call for it.
 
There is nothing wrong with dropping an alternate. As long as you have a new TAF that shows an improved forecast, it's legal.

A few of us had a discussion with our dispatch inspector and he stated it is perfectly legal as long as the new forecast doesn't call for it.


That's true unless it's a flag flight with a duration over six hours. Or, I believe if it is released under supplemental rules. In that case an alternate is always required.
 
There is nothing wrong with dropping an alternate. As long as you have a new TAF that shows an improved forecast, it's legal.

A few of us had a discussion with our dispatch inspector and he stated it is perfectly legal as long as the new forecast doesn't call for it.
Domestically we can drop the alternate as long as the forecast has improved and the alternate is no longer needed. Internationally, we do not need an alternate if the flight is under 6 hours (however there are certain countries that require destination and departure alternates always as per their AIP). Also if we are operating a flight using B044 Planned Re-dispatch, since the flight is technically dispatched twice we are not required to list an alternate for either airport (initial or final destination) if one or both of the flight legs are uner 6 hours.
We also require alternates under flag rules if there is only one suitable runway (except for redispatch), BRAP at the ETA, no tower or a closed tower at the ETA.
 
Also if we are operating a flight using B044 Planned Re-dispatch, since the flight is technically dispatched twice we are not required to list an alternate for either airport (initial or final destination) if one or both of the flight legs are uner 6 hours.

We always list an alternate for both airports when doing a planned re-dispatch, even if the legs are under 6 hours. However, if the weather does not require an alternate at the destination, and it is necessary due to fuel issues, we can drop the destination alternate at time of redispatch. I don't see the point of not providing an alternate for the first leg though - since you always definitely have the fuel for it.
 
So I am taking my practical in two weeks, and I have had conflicting answers from my instructors and wanted to see what everyone else thinks on this scenario.

you get a TAF that reads

KTYS 031124Z 0312/0412 23011G18KT P6SM SCT050 BKN100
FM031400 22014G24KT P6SM SCT040 SCT100 BKN250
FM031900 22019G28KT P6SM VCTS SCT050CB BKN200
FM032200 22020G29KT P6SM VCTS BKN050CB
FM040200 25023G33KT 3SM TSRA BR SCT015 OVC035CB
FM 040400 28022G30KT 4SM SHRA BR OVC020
FM 040700 31017G25KT P6SM OVC020


OK, the question is do we LEGALLY need an alternate? Obviously we would probably plan an alternate because this is just a forecast and we don't know where the thunderstorms will be, or if it will be worse than forecast.

But, from 121.619 "however, no alternate airport is required if for at least 1 hour before and 1 hour after the estimated time of arrival at the destination airport the appropriate weather reports or forecasts, or any combination of them, indicate (1) the ceiling will be at least 2,000 feet above the airport elevation; and (2) visibility will be at least 3 miles"

I am new to all of this, and so I wanted to know if there is a straight forward answer to this, or if anyone else has an opinion on this. My conclusion from reading this is, we don't legally need an alternate here. Because we have the visibility requirement and the ceiling requirement the whole time. But we definitely have convective activity in the forecast. I didn't know if we legally needed one if there was a rule that if we had convective activity, icing, or turbulence in the forecast.

If I were actually dispatching the flight (once I learn everything I need to and actually learn how to dispatch a flight), I would add an alternate because anything can happen with thunderstorms. But if I am asked if I legally need one, I don't want to screw up with the examiner by saying yes or no and not really knowing for sure.

Thanks for the help!
 
So I am taking my practical in two weeks, and I have had conflicting answers from my instructors and wanted to see what everyone else thinks on this scenario.

you get a TAF that reads

KTYS 031124Z 0312/0412 23011G18KT P6SM SCT050 BKN100
FM031400 22014G24KT P6SM SCT040 SCT100 BKN250
FM031900 22019G28KT P6SM VCTS SCT050CB BKN200
FM032200 22020G29KT P6SM VCTS BKN050CB
FM040200 25023G33KT 3SM TSRA BR SCT015 OVC035CB
FM 040400 28022G30KT 4SM SHRA BR OVC020
FM 040700 31017G25KT P6SM OVC020


OK, the question is do we LEGALLY need an alternate? Obviously we would probably plan an alternate because this is just a forecast and we don't know where the thunderstorms will be, or if it will be worse than forecast.

But, from 121.619 "however, no alternate airport is required if for at least 1 hour before and 1 hour after the estimated time of arrival at the destination airport the appropriate weather reports or forecasts, or any combination of them, indicate (1) the ceiling will be at least 2,000 feet above the airport elevation; and (2) visibility will be at least 3 miles"

I am new to all of this, and so I wanted to know if there is a straight forward answer to this, or if anyone else has an opinion on this. My conclusion from reading this is, we don't legally need an alternate here. Because we have the visibility requirement and the ceiling requirement the whole time. But we definitely have convective activity in the forecast. I didn't know if we legally needed one if there was a rule that if we had convective activity, icing, or turbulence in the forecast.

If I were actually dispatching the flight (once I learn everything I need to and actually learn how to dispatch a flight), I would add an alternate because anything can happen with thunderstorms. But if I am asked if I legally need one, I don't want to screw up with the examiner by saying yes or no and not really knowing for sure.

Thanks for the help!

First, what is the scheduled ETA of this flight?
 
That's true unless it's a flag flight with a duration over six hours. Or, I believe if it is released under supplemental rules. In that case an alternate is always required.

Ture on Supp 121, unless you have Exemption 10064B on your specs.
 
Well I didn't really have an ETA. The question was given to us, "at what point do we need an alternate, if we need one at all?"

I said we didn't need one because we had the vis and CIG, but the instructor said if we have convective activity, icing, or turbulence in the forecast, we have to have an alternate.

I just wanted clarification. I know we would want one. But if the examiner asks this same question, I want to make sure I understand this rule all the way. I want to make sure there aren't any other rules that apply here that would make us legally have to add an alternate.

Maybe I'm just reading way too much into this from stressing out. I have never had a test like the practical before, I don't really know how to prepare for this or what to expect.

Thanks for the input!
 
Legally, no. The next question is, should you add one? That depends on a lot of things but in your situation, it wouldn't be hard to explain why you should have one a third of the way into the TAF.
 
Legally, do not need an alternate. If your instructor says you do, simply ask to provide you with the reference that says you require an alternate...
 
Legally, do not need an alternate. If your instructor says you do, simply ask to provide you with the reference that says you require an alternate...

Terrible advice.

What you should do is always disregard everything people you know say and only trust the opinions of strangers on the Internet.
 
Well I didn't really have an ETA. The question was given to us, "at what point do we need an alternate, if we need one at all?"

I said we didn't need one because we had the vis and CIG, but the instructor said if we have convective activity, icing, or turbulence in the forecast, we have to have an alternate.

I just wanted clarification. I know we would want one. But if the examiner asks this same question, I want to make sure I understand this rule all the way. I want to make sure there aren't any other rules that apply here that would make us legally have to add an alternate.

Maybe I'm just reading way too much into this from stressing out. I have never had a test like the practical before, I don't really know how to prepare for this or what to expect.

Thanks for the input!


§121.619 Alternate airport for destination: IFR or over-the-top: Domestic operations.
(a) No person may dispatch an airplane under IFR or over-the-top unless he lists at least one alternate airport for each destination airport in the dispatch release. When the weather conditions forecast for the destination and first alternate airport are marginal at least one additional alternate must be designated. However, no alternate airport is required if for at least 1 hour before and 1 hour after the estimated time of arrival at the destination airport the appropriate weather reports or forecasts, or any combination of them, indicate—
(1) The ceiling will be at least 2,000 feet above the airport elevation; and
(2) Visibility will be at least 3 miles.
(b) For the purposes of paragraph (a) of this section, the weather conditions at the alternate airport must meet the requirements of §121.625.
(c) No person may dispatch a flight unless he lists each required alternate airport in the dispatch release

Per the regs you are good up to 3SM, however alot of dispatchers would consider 3SM alternate adding territory.
For practical purposes you might consider that no alternate is required, but for anything meeting 1-2-3 in the 0200Z line would be smart to have fuel planed to make an alternate, even if not listed as such.

In actual dispatching you will also have an array of radar and weather charts at your disposel to help make descions on to add or not to add an alt/additonal fuel.
 
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