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fuel requirement review.

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Old 8th Nov 2007, 11:25
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fuel requirement review.

can you refresh my memory?

fuel requirement is:

- fuel to destination for 1 approach plus 10% contingency if no wind calculated.

-fuel to alternate (+10% ????) + hold 30 minutes at 1500ft (jet) (hold for turboprop is 45 minutes)

- and add a reserve of 45 minutes.
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Old 8th Nov 2007, 12:52
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Minimum planned fuel:
Taxi
Trip
Contingency (5%)
Alternate fuel
Final reserve (30 mins holding at 1500' aal)

The bottom line is that, to be legal, whereever you land, you must have final reserve fuel in the tanks. You can of course use it if needs be, but you'll have to explain yourself afterwards.
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Old 8th Nov 2007, 18:59
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Actually, not wherever you land. If you land at your destination I think you should have final reserve plus alternate fuel.
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Old 8th Nov 2007, 19:19
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Alexban

If the weather conditions are suitable you can legally use your alternate fuel and commit to your destination airfield. After all why divert to an alternate if you have a perfectly good runway right below you?

SW
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Old 8th Nov 2007, 19:59
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the 5% it's for what?
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Old 8th Nov 2007, 20:46
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5%=en-route continegency.
-weather avoidance requiring deviation from route
-less economical FL
-Higher forecast winds.
Min takeoff fuel at departure should have you arrive at destination able to make an approach, missed approach, diversion, and further approach.
If you land at you destination, and en-route, all went as planned, your arrival fuel should be-
Final reserve allowance
Alternate fuel
Contingency
If you arrive at your destination, and hold (because of an unexpected delay, for instance), but have an assurance that an approach and landing can be made, to not land with less than final reserve fuel, then the alternate fuel can be used to remain over the field/holding fix ready for an approach. An approach time would be good in this instance to calculate the fuel required in this case.
If you arrive at destination, and an approach cannot be made, then you should have fuel enough to go to your alternate. More is nice. But the diversion fuel will get you to diversion, and you should still have final reserve on landing
If at any time you are expecting that you will begin to use the final reserve fuel, then a PAN call is needed.
If you actually start using your Final reserve fuel, A mayday call is required.
Hopefully I got that right.
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Old 9th Nov 2007, 12:33
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keep in mind that the final reserve fuel is equivalent to 30 min hold, it does not mean you will do a 30 min hold with it. If you hold at destination ,using it, then you are commited to land at your destination,no matter what. You have no choise of diverting after you've used your final reserve, as you will arrive at alternate with fumes in reservoir.
If you divert,then when arriving at alternate you'll have fuel for 30 min, starting to use it means a mayday call. So, I doubt you'll use it in hold.
Don't put yourself in the corner, using the final reserve at destination.For us ,minimum at destination is final plus alternate. If you expect less than that,then a technical stop would be required. Followed by tea and biscuits,of course..
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Old 9th Nov 2007, 17:17
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The best way to answer this question if you are operating in accordance with JAR OPS is to direct you to JAR OPS itself.
With the best will in the world the answer to this question can vary hugely depending on the length of the flight, whether your company has an established fuel usage monitoring system, and many other factors. You can see this for yourself if you follow the link below.
It's important to bear in mind (as will see from the document) that the requirements are different if you are planning the flight on the ground, planning the flight in the air, or conducting in-flight fuel monitoring/management after the flight has commenced. This may be why the answers to your post have varied a little.
I know the document may seem a bit daunting but at the end of the day it is the Bible by which JAR Ops operators establish their own policies. These are the policies that we pilots must operate to. Operators can choose to require their pilots to carry more fuel than JAR OPs requires but never less.
http://www.jaat.eu/publications/jars/jar-ops-1.pdf
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Old 10th Nov 2007, 07:19
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....and to save you a lot of 'mousing', start around 1.255, page 1-D-4 'ish (NB it does 'move around a bit' with amendments).
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Old 10th Nov 2007, 08:01
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Alexban,
That is not using your final reserve fuel, it is committing and using your alternate fuel, so that you land at destination with no less than final reserve fuel.
Think of the scenario where you have been given an EAT at a single runway which eats 5 mins into your alternate fuel. You can either:
1) Stay at your destination with "landing assured" and land with (alternate fuel - 5mins) + final reserve fuel or..
2) Divert to alternate field (single runway) and now definitely landing with Final reserve fuel.
The argument that oft comes up is that what happens when you commit to destination and the runway gets blocked.......well I put the theory that what happens if you divert and when on approach with final reserves the runway gets blocked!
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Old 10th Nov 2007, 09:52
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Yes indeed, if you start using your alternate fuel (not final reserve fuel) to either hold at your destination or divert, you are commited to land.
Often your destination is the best choice as long as weather is well above minima.
Better to use some of your alternate fuel to go to your two parallel rwy destination than to use all of your alternate fuel to go to your single rwy alternate?
Some extra fuel makes it a little more relaxed. Ask the 'older' guys, they tell me aviation is about three things: fuel, fuel and fuel!
I suspect they all have been in that corner and they know how it feels to run out of options (which was not very hard to avoid).

Cheers
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Old 12th Nov 2007, 11:09
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I understand here in your posts than once I have start to use the reserve fuel of 30 minutes at destination, I can not fly to alternate anymore?

what happen if I accept a holding clearance at destination and I hold for 15 minutes(by example), and suddenly I am not authorized to land cuz the plane in front of me crashed his gears on the runway?

my only way is to go to alternate, with the rest of 15 minutes holding ...in this case I can declare a "PAN PAN , we are short of fuel"!
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Old 12th Nov 2007, 12:31
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If you have taken flight plan fuel and it all worked out as per the theory (in practice you often make a bit during the flight) YOU DON'T have 30 mins holding fuel, you have none. You must land with a 30 minutes reserve (which is calculated on how much fuel you would require to hold for 30 mins) or declare a mayday if it looks like you won't. If you elect to use your alternate flight plan fuel to hold at destination and the runway becomes blocked it just isn't your day, the basis of the regulations is that it just as likely that your alternate may become blocked as your destination. This is why one of the requirements to use alternate fuel says that the commander must take into account the traffic and operational conditions prevailing at the destination, the route to the alternate and the alternate. An example of the thinking might be:

Holding at single runway destination, short, wet runway, strong crosswind and busy. Alternate is into wind and quiet. Would I burn my alternate fuel?. No, much more chance of getting a blocked runway at destination so I would keep our alternate fuel and divert a little while before the fuel state reaches the critical point so as to be sure to land at the alternate with final reserve. On the other hand it clearly makes no sense to divert if the situation was the other way around.

If as you said you had committed to land at destination and it then became blocked you may have to set off to your alternate (assuming you still have enough fuel to get there, another thing to consider) and land with less than final reserve but you are then in a mayday situation.

Basically it is quite safe to use your alternate fuel to extend your holding at destination but you MUST consider where you are and what options you are losing by doing so, don't do it too lightly just because the rules say you can.

PS. As I am sure has been said before the number of runways makes no difference to the ability to dispense with your alternate but may well influence you decision making, I know it would mine.

Last edited by Max Angle; 12th Nov 2007 at 17:30.
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