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Dispatching with destination bellow minima

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Old 9th Jun 2007, 15:08
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Dispatching with destination bellow minima

For an JAA operator, how you dispatch fuel, flight plan, icao flight plan wise in following case?

Destiantion is forecasted to be bellow minima at ETA +/- 1hr and company wants you to start flight to nearby airport (normaly destination alternate) which is open and pax can be bused to/from original destination, but they also want you to land at original destination should the wx improve by the time you get in the vicinity.

What should they put in ICAO flight plan as destination and how should the flight plan fuel be calculated?

Thanks
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Old 9th Jun 2007, 15:35
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Origin destination plus 2 alternates.
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Old 9th Jun 2007, 15:59
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With the destination weather forecasted to be below minima for the ETA plus/minus one hour, you can stil plan and dispatch the flight to this destination aerodrome, however in this case two (2) destination alternate aerodromes are required acording to JAR OPS 1.

Fuelwise you have to plan with the destiantion alternate aerodrome requiring the higher amount of fuel. This fuel is then to be used as alternate fuel for calculating the minimum fuel required for dispatch.

On the ATC flightplan you have to enter the destination as well as both destination alternate aerodromes. On the manual ICAO flight plan form you will find therefor the field labeled "2nd ALTERNATE AERODROME".

However during flight the pilot in comand may decide to which aerodrome he diverts, this can be any aerodrome and is not limited to the alternate aerodromes mentioned in an ATC flightplan.
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Old 9th Jun 2007, 20:35
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alatnariver, perfect !

And you can play the game to proceed to the alternate until the original destination is below minima, calculating a DPP where you have to choose to proceed to the alternate or "divert" to the original destination.
Once the original destination becomes suitable you can revert to the original planning.

HVIII
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Old 10th Jun 2007, 08:30
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I'll try to explain why I have problem with this:

All the procedures we have in aviation cover for, at least, one (1) eventuality. If one eng. fails there is another one, and even when dest. is cavok we have to have fuel to one altn. in case some eventuality happens (like blocked rwy)...

So, we dispatch as you propose with trip fuel to original (closed) dest + altn fuel to further of two alternates, destination remains closed and we proceed to altn a/p which is behind/beyond destination. We will approach altn a/p with just final reserve fuel or with little extra if are we proceeding to closer altn. However this extra can be zero if two altn. are at same distance from dest.

However in case of just single eventuality, like blocked rwy at that altn, (and closed dest. is not an eventuality since it was predicted as so) we will not have fuel for a "plan B".
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Old 10th Jun 2007, 09:38
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737 incognito

I can see your point a good defensive approach to flying.

I think the requirement for 2 dest alts is designed to cater for a single event at either of them occuring before you make the decision to divert. Once you make the d to divert then I guess statistacaly you are in the same regime as any other diversion.

As an aside if the weather was that poor at Dest I'd carry 1/2 hr of holding fuel ontop of the div requirements, weight permitting to give me thinking time and to give the wx a chance to improve or fuel for a second approach although there is no legal requirement to do so.
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Old 10th Jun 2007, 13:21
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Well I just described the legal limits or what would be legal.

As said before, the pilot in command or as he is called in JAR OPS the commander may decide to take extra fuel. So whenever you feel to take extra fuel you can do so. As the descirbed scenario is in my point of view a very valid reason to take extra fuel, I would do so.

It will get different, if you can't take any extra fuel, as there is no tank capacity left or you would exeed any mass or performance limits.

It of course also depends on the people working in dispatch doing the planning and finaly it also depends on the company's, let's name it culture in respect how to plan and run the flying show.

For example they could plan an aerodrome as destination alternate with two seperate runways, which requires the higher amount of fuel and so be taken as alternate fuel when caculating the minimum fuel. By the way, as a commander you can always request this, at least I can and always could do so. This would give you at least a last option and you are on the safe side. Dispatch can give you some kind of extra or additional fuel, however this might be called internally and finally they may also decide to hold your flight.

Like always we can't cover all possible scenarious, but if you keep comon sense and know what you may do and finally what you are responsible as commander according to JAR OPS, you will find a soulution to this problem. I know this is sometimes hard and you have to stand your ground in the evironment of penny counting people in management, but it is possible.
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Old 10th Jun 2007, 14:49
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What would be your interpretation of this:

JAR-OPS 1.297 Planning minima for IFR flight

(b)
Planning minima for [a] destination [ ]

aerodrome
[ ] [(except isolated destination
aerodromes)
]. An operator shall only select the
destination aerodrome
[ ] when[:]
[(1)] the appropriate weather reports or
forecasts, or any combination thereof, indicate
that, during a period commencing
[one] hour
before and ending
[one] hour after the estimated
time of arrival at the aerodrome, the weather
conditions will be at or above the applicable
planning minima as follows:

I know there is another paragraph in JAR-OPS 1 that says that in case of destination bellow minima you should have two alternates, but honestly, to me this is quite contadictory to above statement that it can not be selected as destination

I may be missing something here

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Old 10th Jun 2007, 16:33
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I think there are LOTS of inconsistencies in the rules, SOPs, OMs etc. I think in those situations one should use common sense and since there's some freedom of interpretation - just choose the option that makes you feel better As long as one knows the regs and is able to back his decision with them - no one should question it. Knowing the rules and those inconsistencies might in fact be an advantage. Want to go? The rules say that if the destination is below minima, you just need 2 alternates. Don't want to go? The rules say you need the wx to be above minima to proceed - it's your choice

Last edited by Stuck_in_an_ATR; 10th Jun 2007 at 16:35. Reason: spelling errors induced by 2 beers
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Old 10th Jun 2007, 19:00
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Planning minima for alternates are one more precaution.

When CAT II or CAT III is available at alternate, you need CAT I RVR/Vis
When CAT I approach is available, you need non precision visibility AND ceiling
For non precision, you have to add 1000m vis and 200ft ceiling

This will help you to stay on the safe side in most of the cases
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Old 10th Jun 2007, 21:28
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737incognito, welcome to JAR!

You are right, there are some unclear paragraphs within the entire set of JAR.

It's good to know, but don't think too much about it, it wont help. Keep in mind that the final authority in regards to how much fuel is taken remains with the commander of a flight. Dispatch can't decide and even the nominated post holder flight operation can't.

So as long as you have a valid reason to take more fuel than plannend take it if you as the commander decide that it will be neccesary for the safe operation of the flight. As long as you don't take extra fuel, becuase you always take 500 kg more for grandma, I doubt that someone would say anything. If so confront them with the regulations.
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Old 11th Jun 2007, 14:46
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You are right, there are some unclear paragraphs within the entire set of JAR.
The other way of looking at it is that there is a lot flexibility and discretion in how you use your fuel and plan your flight. JAA provided numerous fuel planning options and I welcome that.
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Old 11th Jun 2007, 15:10
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I feel that only by taking at least fuel according new (provisional) destination which is open at +/- 1hr gives you the same level of safety. Of course, if original destination opens during flight and you have enough fuel you can land there and save your company some money.

By just having two alternates for closed destination we would have to comit to one of them well in advance with no plan B. That would be same like in cavok day we have to chose between destination and alternate well in advance. Normaly we dont have to, we can choose destination, have some bad luck and still reach alternate

And for your comments that as Captain you can take extra. Yes, on a good day, but how much excatly? We should know exact figure for minimum safe fuel.

As you figured out we are new to JAR and a bit dissapointed that it isnt clear as it should be.
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Old 11th Jun 2007, 15:30
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As long as you, or let's say we, are flying in Europe with lots of aerodormes available to legally land, we have lot's of options. It's different if you do long haule or fly according to JAR in areas where the options are limited.

It's true and I fully agree JAR gives us, as well as our companies, a lot of flexibilty in planning and operating.

In regards to your concern "... as Captain you can take extra... but how much excatly?" I have to say that all airlines I flew for in my career offered an OFP where at least three different destination alternate aerodromes were stated including the required ammount of alternate fule. It maybe that your present company doesn't offer this kind of service, a service it should offer to you, I think!

However if you don't have this data available I am sure you have access to the performance manual of your current aircraft. There you should get some figures to make up an idea of required fuel figures. I know it's an answer that does sound very arrogant, but may be it's worth a try.

Finaly keep in mind that you can always do re- planning in flight and more important to me, you can land at any aerodrome which is suitable, you don't have to fly to the destination alternate aerodrome stated on the operational flight plan or on the ATC flight plan!

I think that the chance to see a change in the rueles regarding fuel planning is not realistic, so we have to live with those rules.
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Old 11th Jun 2007, 17:48
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737incognito
No one can give you an answer as to exactly how much extra as it is extra over and above the legal requirement and comes down to the crews judgement. Personaly I will add either 15 or 30 mins. 15 is another approach and 30 conforms to company guidance on LVPs. I have carried more, every case is individual. As has been mentioned the key is to have thought it out and not to carry a random figure just for grandma. I have also refused to dispatch as Dest was below planning minima and the only 2 legal divs were very marginal and we were carrying a snag that meant we were Cat1 only. Our company provides us with 4 divs on the plan by the way. You can always ask ops for new divs if you don't like the ones you have, they are very helpfull mostly.

At the end of the day the rules have to be observed but within those rules you have to exercise airmanship. Diverting in relatively poor weather worries me less than diverting in good weather. In poor weather I will make sure I have an appropriate fuel load and options which are monitored during the flight. If I don't like it I don't continue. In good weather chances are I'll be carrying plan ie min legal. If I divert now chances are I'll be close to min fuel along with loads of other guys in a similar fix. Could be quite a bun fight when the first pan\mayday goes out and it all ripples down the line. Anyway I digress.
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Old 12th Jun 2007, 16:45
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I dont think I am quite understood here.

You can have fuel for 10th alternate with destination closed, you commit to one of them and than SINGLE suprise, SINGLE event like rwy blocked can mean disaster.
Of course as Captain you can take more fuel but it should be dealt with at the planing stage. Your Flight Plan should protect you from SINGLE eventuality.

having said that it looks that i'm the only one having problem with this so it must be me. If you can't beat them, join them.

thank you for time spent on discussion
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Old 12th Jun 2007, 17:26
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737incog'.

There are the legal boundaries, which may allow you to takoeoff and 'give it a go'; and then there are the airmanship criteria, for which I think the pax pay us to uphold.
In the first instance it may be that destination is a long way off; indeed it might be home base to which you are trying to return. Not helpful to leave a/c & pax grounded far away with little help at hand for long delays. As said, in Europe there should be somewhere as a bolt hole; except remembering one dark night moons ago when everywhere, including the close continent, was out in FZFG. exept PIK & BUB. Since these are in opposite directions it was not helpful.

In the second instance, when ops want you to dispatch to an airfield XYZ which is not your destination ABC, this is what I do. Consider XYZ as planned destination, making sure you have at least the trip fuel for ABC. (It might be that XYZ is shorter nm than ABC.) Then take fuel for an ALTN for XYZ plus all the other bits. Thus you now have a safe fuel plan when you depart. Should ABC become suitable nearing XYZ then you can make an approach at ABC and you will have fuel to divert to XYZ should it fail. There is no complicated 'how much extra shall I take' etc. It is a simple straight forward fuel plan as any other flight, but gives you all the flexibility you need. Of course, you might want 2 shots at ABC, so enough for the second approach might be all the extra you need.

Before JAR, in the good old days, the fuel so required was enough to make an approach at original destination, have 2 ALTN's, G/A, divert to further ALTN, given that both ALTN's were in the same direction; hence my quip about PIK & BUB. Of course you would land at the nearer ALTN. That might have been company rules rather than CAA, but it made common sense. I do not think JAR has banned common sense; hopefully.
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Old 13th Jun 2007, 00:40
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Well maybe I didn't understand you and I am still not sure if I understand you know.

But in my opinion and for the company I am flying presently we have always to keep two (2) landing options and that's what I always do, well may be that there might one day be when I will have only one option left.

Take it like this, if you plan a flight according to JAR with the weather forecatsed for the destination aerodrome to be above the applicable operating minima at +- 1 hrs. ETA, you will plan with one destination alternate aerodrome. Makes two (2) possible landing options for me.

Now back to the original problem with the destination aerodrome to be forecasted below applicable operating minima at +-1 hrs. ETA. As per JAR you have to plan now using two destination alternate aerodromes, both of them must be above the alternate planning minima. You have two (2) possible landing options again, the two destination alternate aerodromes.

Also keep in mind that the alternate planning minima are more conservative than the planning minima for the destination aerodrome.

For sure **** can happen, but you can't put up a set of rules that will cover reallz all eventualities in live. The regulations have to be practible in everyday live. For the rest just use you common sense or set up you private line of defense. Maybe you are happy if one of the alternate aerodromes in case of destination aerodrome below planning minima, has two seperate runways, well that's fine use it, so there are in fact three (3) landing surfaces, at least at the planning stage of a flight. As said before request from dispatch an alternate or alternates you are happy with. That's still one option a commander has.
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Old 13th Jun 2007, 11:02
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When dest. is cavok why we carry fuel for alternate. Because it can get closed for non-wx reasons. Same can happen for one of your two (or 3 or 4) alternates. And it can happen just 3 miles from touchdown. And it is not 5th thing that went wrong on given day , it is the FIRST (since dest was closed before dep) thing at bad moment.

Surely I feel strong about this oterwise I would let it be
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Old 13th Jun 2007, 12:30
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737 Incog

Not sure how you're arriving at first alternate with just final reserve fuel. Lets say you've dispatched to a closed destination with 2 useable alternates and you've taken plog fuel, ie fuel for the furthest alternate. You have 2 possible scenarios in flight:

1. Destination opens. You make an approach there, you have to go around and divert to Alt 1 arriving with slightly more than final reserve because you had fuel for the farther Alt 2.

2. Destination does not open. You therefore make an approach to Alt 1, you have to go around and divert to Alt 2 arriving with around final reserve fuel depending on the respective distances between the 3 airports.

In each case you've made 2 approaches with a diversion to get to final reserve, same as on any normal day. The only thing you do need to be aware of before you go is the relative positions and distances of the 3 airports but you'd do that for any flight anyway.
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