Redispatching flights

A1TAPE

Well-Known Member
How common are redispatches for when your alternate goes below alternate wx minimums? Do you ever have to redispatch a flight more than once? Also for alternate selection do you have some favorite airports to use for alternates that are in your c70 list? Finally realistically speaking how far away from bad wx at the destination does the alternate have to be for the flight to have a shot at landing if they divert?
 

4EngineETOPS

Well-Known Member
How common are redispatches for when your alternate goes below alternate wx minimums? Do you ever have to redispatch a flight more than once? Also for alternate selection do you have some favorite airports to use for alternates that are in your c70 list? Finally realistically speaking how far away from bad wx at the destination does the alternate have to be for the flight to have a shot at landing if they divert?
Redispatch and amending an alternate under 121.631 have nothing to do with each other. Redispatch is a method of saving fuel or increasing available payload by carrying 10% international reserves only from the planned redispatch point to the intended destination. An updated evaluation of fuel requirements, weather, and NOTAMs is required within 2 hours of the redispatch point for the flight to continue (i.e. be redispatched to) the intended destination. Failing any of those parameters results in going to the redispatch destination (where the aircraft was legally released to originally).

Changing an alternate is an entirely different concept: 14 CFR § 121.631 - Original dispatch or flight release, redispatch or amendment of dispatch or flight release.. You can't redispatch multiple times in a single flight. See above.

There are a lot of considerations in alternate selection. You don't always need an alternate if you are operating under domestic/flag rules (ref OpSpecs/regs). My favorite alternate airports are the ones that have solid weather (if possible) and are a reasonable distance from the destination. The actual airport depends on what the big picture weather situation is, there's no set distance that an alternate "should" be. I've listed alternates almost 2 hours away when the weather is bad at an international destination and there are no suitable airports nearby (obviously if payload has to come off to accommodate an alternate like that, there's further consideration/discussion to be had). With a narrow band of rain/low ceilings, clearing conditions behind a front, other obvious localized weather phenomena, or even situations with airport facilities, the alternate can often be quite close to the destination. If the destination and other nearby airports are showing telltale signs of fogging in (early morning, calm winds, low temp/dewpoint spread, cool temperatures, nearby bodies of water, etc), then it's probably a good idea to pick an alternate that isn't in the same zip code. Similarly, I don't pick an alternate on the other side of a solid convective line since the aircraft can't just teleport to the alternate. Company facilities, airport size/capacity, ATC TMIs/restrictions, and numerous other factors can play into both flight plan alternate selection and the actual decision to divert to a particular airport. If at all possible, I try to avoid being last in line for fuel at a major hub without company mx/fuel arrangements that's over diversion capacity (with 3 hour EDCTs in effect to top it off). Obviously, safety comes first.
 

SpaceBeagle

Located in Low Earth Orbit
Just to add on to your post, redispatch is planned thing. Which means, all the weather, notams, burns, and all that for the initial destination, initial alternate, final destination, and final alternate are all on the release. Once planned, a redispatch will happen during the previously mentioned two hour window unless you decide to stop at your initial destination or decide on a change of destination somewhere short within fuel range. You’re basically doing a re-evaluation of the fuel scenario because things may have changed, such as routing, weather deviations, or being restricted to a certain altitude across the pond. If you have enough fuel, great, awesome, you get to go to your real destination. If not, you go to the initially cleared destination which you definitely have fuel for.

Changing alternates is indeed a different thing, and it happens all the time. No redispatch is involved, alternate simply must be changed and burns re-evaluated. If theres no alternates within fuel range, a change of destination may be required. This can also be done on the original release, without redispatch.
 

DispatchDan

Well-Known Member
Yup, as the previous two posts stated... don’t confuse re-releasing ( or amending ) a flight to re-dispatching. Re-dispatching falls under Opspec B44 and it’s for flag operations.
 

A1TAPE

Well-Known Member
So it’s just an amendment for DOMESITIC ops? And a redispatch for FLAG (international) ops?
 

4EngineETOPS

Well-Known Member
Yup, as the previous two posts stated... don’t confuse re-releasing ( or amending ) a flight to re-dispatching. Re-dispatching falls under Opspec B44 and it’s for flag operations.
Rerelease is the term used for supplemental flights released under B044 since the person exercising operational control isn't legally putting their dispatch certificate on the line.

So it’s just an amendment for DOMESITIC ops? And a redispatch for FLAG (international) ops?
You can amend a flight plan under domestic, flag, and supplemental rules. Amendments are simply changes to the flight plan that include fuel changes, route amendments, DMI additions or subtractions, etc. Redispatch is the specific act of signing off, under your dispatch authority, the continuation of a flight beyond the redispatch point to the intended destination under flag rules and OpSpec B044. Rerelease is the same thing, except under supplemental rules and using the operational control function (not responsibility) delegated by the DO. Again, B044 redispatch/rerelease and flight plan amendments are entirely unrelated concepts.
 

DispatchDan

Well-Known Member
Rerelease is the term used for supplemental flights released under B044 since the person exercising operational control isn't legally putting their dispatch certificate on the line.
??? Not sure if I understand what you are saying, but re-dispatch as in using Opspec B044 is not just supplemental it’s very much used by the major airlines on scheduled international (flag) operations and the dispatcher puts his/her license on the line every time
As far as joint responsibility, there is noting different when re-dispatching ( using B044 ) a flight.
All it does it reduces that 10% fuel and if re-dispatch fix is less then 6 hours from your destination you can go without an alternate if you have required WX
 

4EngineETOPS

Well-Known Member
??? Not sure if I understand what you are saying, but re-dispatch as in using Opspec B044 is not just supplemental it’s very much used by the major airlines on scheduled international (flag) operations and the dispatcher puts his/her license on the line every time
As far as joint responsibility, there is noting different when re-dispatching ( using B044 ) a flight.
All it does it reduces that 10% fuel and if re-dispatch fix is less then 6 hours from your destination you can go without an alternate if you have required WX
You had said "don’t confuse re-releasing ( or amending ) a flight to re-dispatching," so I was just clarifying that a rerelease is not the same as amendment and that redispatch = rerelease in practice. B044 specifies in the first few sentences that rerelease is the supplemental equivalent of redispatch. The term is just different due to the legal distinction between supplemental flight followers and domestic/flag dispatchers. Just semantics.

Also how does redispatching put your license on the line every time?
The act of redispatch (i.e. the flag term for B044) "puts your license on the line" because you are effectively signing an updated release for the flight to continue to the intended destination. By certifying that the flight may continue past the redispatch point as planned, you are exercising your 121.535 authority.
 
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757Geek

Well-Known Member
I would add that re-dispatching is also any time that a change of destination takes place where you cannot land at the intended destination and the airport is not listed on your release as an alternate. While this is pretty rare it can happen occasionally domestically and this is given to dispatchers in 121.533.
 

DispatchDan

Well-Known Member
I would add that re-dispatching is also any time that a change of destination takes place where you cannot land at the intended destination and the airport is not listed on your release as an alternate. While this is pretty rare it can happen occasionally domestically and this is given to dispatchers in 121.533.
This is re-releasing a flight or amending a flight, it’s not re-dispatching a flight
 

757Geek

Well-Known Member
So is changing a destination enroute domestically. If you change a destination then you must have the fuel requirements that is required to dispatch from an origin airport (burn to destination plus 45 minutes plus burn to any alternate) as well as weather requirements in regards to needing an alternate or not. As I said previously 121.533 gives domestic dispatchers the authority for re-dispatch, which is what changing your destination is. 121.535 is in regards flag re-dispatching.
 
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DispatchDan

Well-Known Member
But that is not correct.
Both international and domestic, if you are enroute and for some reason you have to change destination and it’s not going to your listened alternat, then you re-release or amend the the flight... saying “captain release 2 to change destination... “ or “amend release to change destination...”
Re-dispatching is the type of release for international flights where you send an original release 1 as a re-dispatch release.
You are releasing a flight AMS-DFW. Instead of doing a straight release, where you have to added 10% of total burn from AMS-DFW, you do a re-dispatch release going from AMS-JFK and at a fix around JFK (within 2 hours of that fix) you recalculate your fuel and if you didn’t overburn, you re-dispatch the flight from that fix to DFW. And all that information is already on the original release, this is not amending the release and sending a new release. In this case your 10% fuel instead of being from AMS-DFW, now is from AMS-JFK... and if you didn’t overburn and that 10% hasn’t been touched it is enough to cover the 10% you need from that re-dispatch fix (near JFK) to DFW. I know this is hard to explain in writing on this forum, but again re-dispatch is a type of release, and it’s all a part of the original release 1. Re-dispatching doesn’t mean changing or amending your release. Hope this explains it a little better.
 

757Geek

Well-Known Member
I don’t disagree about flag re-dispatching and I understand it, but my follow up question is why do the FARs give domestic only dispatchers the authority to re-dispatch if everyone on this forum is saying domestic dispatchers don’t and can’t re-dispatch? Is this an old rule from the 30s where they could re-dispatches DC-3s?
I guess all I’m arguing is that domestic dispatchers have the authority to re-dispatch as well as given to us in the FARs. The only way I can see it is in an example where I have a flight from DEN-LGA and LGA stops arrivals cause someone went off the runway and I am changing my destination to MDT for example. Per my company policies and as far as I know according to the FARs I have to have met all the requirements for MDT as I did to dispatch to LGA. To me that’s re-dispatch not amending a release.
I know that I am probably in the minority in this opinion but it’s always been my understanding of what the FARs grant us. I know this is hardly ever planned domestically, I’m just trying to argue how this authority extended to us can be applied domestically.
 
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DispatchDan

Well-Known Member
You are correct that you have to change destination and you have to have the fuel to get to you new destination and if the WX requires it, you need to name an alternate and have fuel to your alternate as well as 45min of reserve fuel... however, every time I did that all I did was send a new release or amending my current release.... so technically I view it as re-releasing the flight, or amending the release, but still completely different then a re-dispatch release. Might be just how I see it.
 

4EngineETOPS

Well-Known Member
I agree with @757Geek here, and I was not precise enough with my terminology before. The title of OpSpec B044 is "Planned Redispatch or Rerelease Enroute," with the term "planned" being included for a reason. The definition pulled straight from B044 is, "a planned redispatch or rerelease is one that is planned before takeoff to be redispatched or rereleased, in accordance with §121.631(f) at a predetermined point along the route of flight to an airport other than that specified in the original dispatch or flight release." The referenced 121.631(f) also makes it clear that an unplanned redispatch/rerelease can occur when the destination is changed to any airport other than the originally planned destination: "No person may change an original destination or alternate airport that is specified in the original dispatch or flight release to another airport while the aircraft is en route unless the other airport is authorized for that type of aircraft and the appropriate requirements of §§ 121.593 through 121.661 and 121.173 are met at the time of redispatch or amendment of the flight release."

While redispatch/rerelease (distinct from "planned redispatch/rerelease") is not expressly defined anywhere, it is clear based on the term's usage in B044, 121.631(f), and 121.533(c)(3)/121.535(c)(3) that an unplanned redispatch/rerelease is a change of destination to an airport other than the original destination. Dispatching a flight is releasing it to a specific airport (the original destination) in compliance with all 14 CFR requirements (including weather minimums, alternates, etc.). You can amend any part of the dispatch release other than the destination, including changing the planned alternate. Once it is decided that the flight will divert to the planned alternate or any other suitable airport, then the flight is redispatched/rereleased to the new destination since the original destination has been changed. In essence, my interpretation of 121.533, 121.535, and 121.631 is that a flight must be dispatched or released to any airport intended as a destination. If the destination changes any time after the dispatch release has been signed (including when the flight is enroute), the requirement for a legal release to the new destination airport is still in effect (hence the term redispatch or rerelease). The exception to this rule would be when the PIC's emergency authority is exercised.

I do object to rerelease and amend being used interchangeably because the term rerelease is specifically used for B044 operations under supplemental rules. Since supplemental operations do not have dispatchers (rather, "persons who exercise operational control" or flight followers), the flight must be released (rereleased) rather than dispatched (redispatched). The first paragraph of B044 states, "The certificate holder is authorized to conduct planned redispatch for flag operations or planned rerelease for supplemental operations."

I know this is all semantics in some sense, but terms like the above can be used rather loosely and become confusing when actually examined. What I would define each term as is:

AMEND: To change any aspect of the flight plan, other than the destination. This would include planned alternates, fuel numbers, routes, DMIs, and other non-destination aspects. Ref: 121.631(b) and 121.631(f).

REDISPATCH: Applicable to domestic and flag operations. The act of changing the destination to another C070 airport, whether or not the new destination was the planned destination alternate. Ref: 121.533(c)(3) for domestic, 121.535(c)(3) for flag, and 121.631(f) for both.

RERELEASE: Applicable to supplemental operations. The act of changing the destination to another suitable airport within authorized B050 areas of operation, whether or not the new destination was the planned destination alternate. Ref: 121.631(f). The term release, rather than dispatch, is used per the above definition from the first sentence of B044.

PLANNED REDISPATCH: Applicable to flag operations. A redispatch that has been planned in accordance with B044, with all required information listed on the original flight plan. Ref: B044.

PLANNED RERELEASE: Applicable to supplemental operations. A rerelease that has been planned in accordance with B044, with all required information listed on the original flight plan. The difference is terminology is due to the legal operational control differences between flag dispatchers and supplemental flight followers.

If anyone has a different interpretation, I am open to it. I just think it's important to be clear on the terminology when it can easily become muddled.
 

SpaceBeagle

Located in Low Earth Orbit
While it is true that the FARs allow for redispatch, the airline’s Op Specs have to specifically allow for it. A good place to check is A004. At my shop:

The certificate holder is not authorized and shall not:

Conduct planned redispatch or rerelease en route. B044
Yet we can change the alternate or destination all day, because it’s simply a different thing. To perform a redispatch/release, you need this Op Spec and you have to comply with all the provisions of B044. Redispatch is much more involved and takes a lot longer than an amendment or a change of destination, especially if ACARs or the Satphone isn’t working!
 
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