6 minutes contingency
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6 minutes contingency
Yesterday on our OFP we had a 6 minutes contingency. I have not found anything in the IR-OPS and our OMA that references a 6 minute contingency, but only a 5% of trip fuel or 5 minutes at 1500 ft AAL above destination aerodrome.
Any hints?
Any hints?
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Our flight plans are for max payload, but the actual payload is often less than that so we always have some extra fuel when we arrive at destination, and we did indeed land with fuel well in excess of minimum diversion fuel. 4 tonnes if I remember well.
But I don't understand how a 6 minute contingency comes from, it is s the first time I've seen it.
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PBC, or prescriptive based compliance is allowable for contingency fuel planning if the Operator can demonstrate to the satisfaction of the Regulatory Authority that fuel is allocated as described in the Standards and Recommended Practices. (ICAO Annex 6)
The ICAO Document 9976, Flight Planning & Fuel Management Manual (FPFM) states:
4.18.6 An example involves an operator that does not carry five per cent contingency fuel exactly as defined in Annex 6, Part 4.3.6.3. An Authority may consider an operator in prescriptive compliance without the need for an operational variation if the terminology and contingency fuel calculation method used results in a demonstrably equivalent (or greater) amount of fuel. Conversely, an operator may be deemed out of compliance or require an operational variation if the terminology used is largely inconsistent with 4.3.6.3 c) and/or the calculation method used results in a lesser amount of fuel.
As your 6 minutes of contingency exceeded the typical ‘5% of trip fuel or 5 minutes at 1500’AAL’ fuel then you are in compliance with the regs based on PBC. I do agree however that an e-mail to ops would satisfy your curiosity, as technically they are not implementing what is documented in your OMA.
The ICAO Document 9976, Flight Planning & Fuel Management Manual (FPFM) states:
4.18.6 An example involves an operator that does not carry five per cent contingency fuel exactly as defined in Annex 6, Part 4.3.6.3. An Authority may consider an operator in prescriptive compliance without the need for an operational variation if the terminology and contingency fuel calculation method used results in a demonstrably equivalent (or greater) amount of fuel. Conversely, an operator may be deemed out of compliance or require an operational variation if the terminology used is largely inconsistent with 4.3.6.3 c) and/or the calculation method used results in a lesser amount of fuel.
As your 6 minutes of contingency exceeded the typical ‘5% of trip fuel or 5 minutes at 1500’AAL’ fuel then you are in compliance with the regs based on PBC. I do agree however that an e-mail to ops would satisfy your curiosity, as technically they are not implementing what is documented in your OMA.
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I've done some further research and it may be that the contingency fuel was based on city pair/aeroplane combination statistical method.
an amount of fuel based on a statistical method that ensures an appropriate statistical coverage of the deviation from the planned to the actual trip fuel. This method is used to monitor the fuel consumption on each city pair/aeroplane combination and the operator uses this data for a statistical analysis to calculate contingency fuel for that city pair/aeroplane combination
CAT.OP.MPA.150
I will of course enquire my flight ops department.
AMC1 CAT.OP.MPA.15
an amount of fuel based on a statistical method that ensures an appropriate statistical coverage of the deviation from the planned to the actual trip fuel. This method is used to monitor the fuel consumption on each city pair/aeroplane combination and the operator uses this data for a statistical analysis to calculate contingency fuel for that city pair/aeroplane combination
CAT.OP.MPA.150
I will of course enquire my flight ops department.
AMC1 CAT.OP.MPA.15
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At BA, we call it SCF (statistical contingency fuel). We usually operate to a 95% coverage which allows you to take flight plan fuel in the knowledge that it’s highly unlikely you’ll need more unless the weather is particularly bad etc etc.
If they used this method for you, I’m surprised you were not aware of its existence though. It should be explained in OM-A I would’ve thought.
champ
If they used this method for you, I’m surprised you were not aware of its existence though. It should be explained in OM-A I would’ve thought.
champ
I've done some further research and it may be that the contingency fuel was based on city pair/aeroplane combination statistical method.
an amount of fuel based on a statistical method that ensures an appropriate statistical coverage of the deviation from the planned to the actual trip fuel. This method is used to monitor the fuel consumption on each city pair/aeroplane combination and the operator uses this data for a statistical analysis to calculate contingency fuel for that city pair/aeroplane combination
CAT.OP.MPA.150
I will of course enquire my flight ops department.
AMC1 CAT.OP.MPA.15
an amount of fuel based on a statistical method that ensures an appropriate statistical coverage of the deviation from the planned to the actual trip fuel. This method is used to monitor the fuel consumption on each city pair/aeroplane combination and the operator uses this data for a statistical analysis to calculate contingency fuel for that city pair/aeroplane combination
CAT.OP.MPA.150
I will of course enquire my flight ops department.
AMC1 CAT.OP.MPA.15
The EASA rules I think are
(c) Contingency fuel, which should be the fuel described in (1) or (2) below, whichever is higher:
(1) either:
(i) not less than 3 % of the planned trip fuel or, in the event of in-flight replanning, 3 % of the trip fuel for the remainder of the flight provided that a fuel en route alternate (fuel ERA) aerodrome is available; or
(ii) an amount of fuel sufficient for 20 min flying time based upon the planned trip fuel consumption; or
(iii) an amount of fuel based on a statistical method that ensures an appropriate statistical coverage of the deviation from the planned to the actual trip fuel; prior to implementing a statistical fuel method, a continuous 2-year operation is required during which statistical contingency fuel (SCF) data is recorded — note: in order to implement a SCF on a particular city pair/aeroplane combination, sufficient data is required to be statistically significant; this method is used to monitor the fuel consumption on each city pair/aeroplane combination, and the operator uses this data for a statistical analysis to calculate the required contingency fuel for that city pair/aeroplane combination; or
(2) an amount to fly for 5 min at holding speed at 1 500 ft (450 m) above the destination aerodrome in standard conditions.
What you would have loaded is the 5 minutes, your statistical contingency must be less than that amount. This typically occurs where the departure and arrival procedures have complicated/inefficient routing (like maintaining below 7000 ft for 70 miles, and then a zig zag STAR) which are there typically for loss of communications purposes. When radar identified significant shortcuts are normally available reducing the actual trip distance/fuel down significantly. Have a look at the planed trip distance compared to the actual distance flown on flight radar or similar. My guess is you are typically seeing a saving of around 100 nm over the city pair which is converted into contingency fuel via the statistical method.
What you would have loaded is the 5 minutes, your statistical contingency must be less than that amount.
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I am retired, thanks to a god who forgot to point his finger at me during my career...
I admire your knowledge, your professional curiosity and I love reading the tech logs.I wish you all the best during these difficult times. But here I feel compelled to say STOP!
Who cares about five minutes six minutes and statistical survey of approaches for the last fifty years?
Take a reasonable amount of fuel using your knowledge and experience. Never let the statisticians dictate you anything. Ask your copilot if he is happy with the fuel you decided to take. That's important. And stay cool...very cool...Aviation is a very simple art complicated by people who do not have a very happy life. And they are more obtrusive as times goes by...
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But here I feel compelled to say STOP!
Who cares about five minutes six minutes and statistical survey of approaches for the last fifty years?
Take a reasonable amount of fuel using your knowledge and experience. Never let the statisticians dictate you anything. Ask your copilot if he is happy with the fuel you decided to take. That's important.
Who cares about five minutes six minutes and statistical survey of approaches for the last fifty years?
Take a reasonable amount of fuel using your knowledge and experience. Never let the statisticians dictate you anything. Ask your copilot if he is happy with the fuel you decided to take. That's important.
Dear friends...
I am retired, thanks to a god who forgot to point his finger at me during my career...
I admire your knowledge, your professional curiosity and I love reading the tech logs.I wish you all the best during these difficult times. But here I feel compelled to say STOP!
Who cares about five minutes six minutes and statistical survey of approaches for the last fifty years?
Take a reasonable amount of fuel using your knowledge and experience. Never let the statisticians dictate you anything. Ask your copilot if he is happy with the fuel you decided to take. That's important. And stay cool...very cool...Aviation is a very simple art complicated by people who do not have a very happy life. And they are more obtrusive as times goes by...
I am retired, thanks to a god who forgot to point his finger at me during my career...
I admire your knowledge, your professional curiosity and I love reading the tech logs.I wish you all the best during these difficult times. But here I feel compelled to say STOP!
Who cares about five minutes six minutes and statistical survey of approaches for the last fifty years?
Take a reasonable amount of fuel using your knowledge and experience. Never let the statisticians dictate you anything. Ask your copilot if he is happy with the fuel you decided to take. That's important. And stay cool...very cool...Aviation is a very simple art complicated by people who do not have a very happy life. And they are more obtrusive as times goes by...