Originally posted by mfeldt
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The aircraft left the gate with a calculated weight of 233,257 kg. The estimated
takeoff weight was 232,757 kg(11), for a maximum authorised takeoff weight of
233 t. This takeoff weight broke down as follows:
empty weight in operating condition: 126,010 kg,
passenger weight: 17,615 kg (126 men, 82 women, 7 children and one baby(12)),
weight in cargo compartment (freight and luggage): 18,732 kg,
fuel weight: 70,400 kg.
The on-board fuel weight corresponded to forecast trip fuel of 63,900 kg,
route factor fuel of 1,460 kg, final reserve of 2,200 kg, fuel to alternate airport
reserve of 1,900 kg and 940 kg additional fuel.
Regulatory fuel:
The regulatory fuel necessary to perform a flight is determined at brake release before
takeoff, thus 69.5 t in this case.
takeoff weight was 232,757 kg(11), for a maximum authorised takeoff weight of
233 t. This takeoff weight broke down as follows:
empty weight in operating condition: 126,010 kg,
passenger weight: 17,615 kg (126 men, 82 women, 7 children and one baby(12)),
weight in cargo compartment (freight and luggage): 18,732 kg,
fuel weight: 70,400 kg.
The on-board fuel weight corresponded to forecast trip fuel of 63,900 kg,
route factor fuel of 1,460 kg, final reserve of 2,200 kg, fuel to alternate airport
reserve of 1,900 kg and 940 kg additional fuel.
Regulatory fuel:
The regulatory fuel necessary to perform a flight is determined at brake release before
takeoff, thus 69.5 t in this case.
The required fuel when landing at CDG is the 2200kg of final reserve plus the 1900kg to fly to the alternate. That's the 4.1t mentioned as needed for a legal landing.
If the flight went exactly as planned, the trip fuel would have gone, leaving the route reserve of 1450 kg and added to the 940 kg of additional fuel that makes 2390 t of fuel that would be in the tanks, in addition to what's the regulatory minimum, when landing at CDG (again, if the flight went as planned and the route reserves are not used). That's the 2.4 t mentioned as available as "additional reserve to circumvent weather while keeping the 4.1t" required for a legal landing at CDG.
And those 2.4 t reportedly equals to about 20 minutes of curise flight (or some 157 NM no wind, ISA, FL350, M0.82)
If that's correct, the "regulatory" route reserves of 1460 kg would have been good for:
20 min * 1.46/2.39 = 12 min
157 NM * 1.46/2.39 = 96 NM
And that would be legal route reserves for a DTC such a long flight from Rio to CDG???? It looks so, because that's basically the nmbers of flight plan 2 that was DTC.
I tend to agree with Evan here. To my untrained eyes, that looks ridicously low for a route reserve, unless you are willing to try to land at CGD with less than alternate + 30 minutes (and maybe havinng to miss the approach and go for the alternate, landing there with less than the famous 30 minutes)
That brings another question. How can Orly be a useful alternate to CDG??? (unless CDG gets closed for something other than weather)
So Huettig's commentary was not that there was an actual shortage of fuel, but simply that due to the usage of the re-clearance procedure the crew was forced to balance their decisions with fuel consumption in mind in order not to jeopardize a punctual landing at CDG already at that stage of the flight.
Now I admit I'm puzzled.
Once again the RIF strategy is NOT the issue here. If the crew was under pressure to avoid a fuel stop in this RIF flight, the pressure would have been exactly the same with a DTC flight on the same fuel at TO.
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