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Plane ‘carrying football team from Brazil’ crashes in Colombia.
I sort of recall you taking us on a Gabrielesque journey down the path of 'a transport category aircraft must always be able to land safely at MTOW'
Maybe it is here:
§25.473 Landing load conditions and assumptions.
(a) For the landing conditions specified in §25.479 to §25.485 the airplane is assumed to contact the ground—
(1) In the attitudes defined in §25.479 and §25.481;
(2) With a limit descent velocity of 10 fps at the design landing weight (the maximum weight for landing conditions at maximum descent velocity); and
(3) With a limit descent velocity of 6 fps at the design take-off weight (the maximum weight for landing conditions at a reduced descent velocity).
Yes, but I was not talking about the landing, but about the marginal ability to clear terrain and obstacles and hold altitude in the event of a dual engine failure (in a plane with 3 or 4 engines).
Anyway, this is completely OT and inconsequential. It was intended to be just a joke about BB's comment that you cannot have too much fuel except in a fire.
Ok, let me clarify what I meant (and this addresses Evan's "uh oh")
§ 121.193 Airplanes: Turbine engine powered: En route limitations: Two engines inoperative.
I sort of recall you taking us on a Gabrielesque journey down the path of 'a transport category aircraft must always be able to land safely at MTOW'
Maybe it is here:
§25.473 Landing load conditions and assumptions.
(a) For the landing conditions specified in §25.479 to §25.485 the airplane is assumed to contact the ground—
(1) In the attitudes defined in §25.479 and §25.481;
(2) With a limit descent velocity of 10 fps at the design landing weight (the maximum weight for landing conditions at maximum descent velocity); and
(3) With a limit descent velocity of 6 fps at the design take-off weight (the maximum weight for landing conditions at a reduced descent velocity).
"On a more serious note, there are other instances where you may have too much fuel like a double engine failure in a 3 or 4 engines plane. This is more a weight than a fuel issue, but fuel is easier to dump than pax or cargo!"
This kind of sounded like you did not understand that, but I see you do.
Ok, let me clarify what I meant (and this addresses Evan's "uh oh")
§ 121.193 Airplanes: Turbine engine powered: En route limitations: Two engines inoperative.
(c) [...] No person may operate a turbine engine powered airplane along an intended route unless [...]:
(2) Its weight, according to the two-engine inoperative, en route, net flight path data in the Airplane Flight Manual, allows the airplane to fly from the point where the two engines are assumed to fail simultaneously to an airport [...], with the net flight path (considering the ambient temperatures anticipated along the track) clearing vertically by at least 2,000 feet all terrain and obstructions within five statute miles (4.34 nautical miles) on each side of the intended track [and] The net flight path has a positive slope at 1,500 feet above the airport where the landing is assumed to be made after the engines fail.
And this is considering the option of fuel dump (if available). So the scenario is that it is perfectly legal that you lose 2 engines and, while descending towards an airport, you start dumping fuel but even then you are able to hold the altitude with the other 1 or 2 engines at MCT when you go all the way down to 1501 ft above the diversion airport, and that is with the airplane in clean config and with the wings level. Gear down, flaps 1 or turn, and you may be unable to hold the altitude.
At that point, you may be wishing you were lighter (read: that you had not put so much fuel way beyond the required amount).
(to be fair, the net flight path has a margin of 0.3% to 0.5% gradient over the flight path gradient demonstrated in the test flights)
(to be fair II, the chances of that happening are extremely slim. How many times did 2 (but not all) engines fail?)
I know, and it is not just in the 747. Virtually all planes bigger than a small GA one have a MTOW that is heavier than its MLW, even planes that do not have fuel dump systems (which is most of the single aisle airliners, and hence most of the commercial airplanes today). But they are all certified to land with more than the MLW, up to the MTOW (a special post-heavy-landing inspection may apply, though).
Did I say something that sounded like contrary to that?
"On a more serious note, there are other instances where you may have too much fuel like a double engine failure in a 3 or 4 engines plane. This is more a weight than a fuel issue, but fuel is easier to dump than pax or cargo!"
This kind of sounded like you did not understand that, but I see you do.
And Gabriel, More often than not in the 747 we take off with more fuel than we can land with. That is what fuel dump systems and overweight landings are for.
I know, and it is not just in the 747. Virtually all planes bigger than a small GA one have a MTOW that is heavier than its MLW, even planes that do not have fuel dump systems (which is most of the single aisle airliners, and hence most of the commercial airplanes today). But they are all certified to land with more than the MLW, up to the MTOW (a special post-heavy-landing inspection may apply, though).
Did I say something that sounded like contrary to that?
Or when the fuel exceeds the fuel capacity, as it would have here.
That is not having too much. That is having NOT enough!
And Gabriel, More often than not in the 747 we take off with more fuel than we can land with. That is what fuel dump systems and overweight landings are for.
There was an opportunity to catch this before it happened. The flight plan was absurd. EET=Duration??!! Nobody minding that store. There was an opportunity to catch this in flight. Feed tanks low=a master warning, well before full exhaustion, with ample fuel for diversion AND go-around. No one minded that. There is an opportunity to catch these types of violations after they land. Nobody minding that store either. Why aren't revenue flight plans being scrutinized and approved by an aviation authority? Why isn't remaining fuel logged and checked by an aviation authority? Why do we place our faith in pilots who may be under pressure from careless operators? Somewhere, someone has to keep everyone honest, that's part of the social contract, because, without that, we will live in "continual fear, and danger of violent death", and human life would be "solitary, poor, nasty, brutish and short".
*Procedures to report fuel remaining at the end of a flight.
-Human reporting
-Automated reporting
-Existing systems?
*Aircraft automatically reports low fuel status to ATC via Transponder (or some other system)
I'm a bit surprised that the ole topics of Pilot Screening and Safety Culture have not_had their usual rants...
Yeah, they've been mentioned, but really, isn't this just a gross failure of the pilots using super basic fundamentals AND (or for Evan) EVEN EXISTING, GOOD, HARD PROCEDURES to plan for fuel, monitor for fuel in flight and act accordingly.
(Yeah, I'm guilty of wanting them to have the excuse of winds throwing them a curve ball, but monitor, bail and declare-an-emergency-if-needed can't really be dismissed...Still do not want to accept them departing with the plan being to arrive with less than 15 min of fuel left.)
Think I will go with what I have used over the last 45+ years.
What I guess is basically "do not run out of fuel", I suppose.
Only time you have to much fuel on-board is when you are on fire!
Or when you miscalculated your take-off weight (lower than real), hence set a too low TO thrust, and you don't have a TOPMS.
On a more serious note, there are other instances where you may have too much fuel like a double engine failure in a 3 or 4 engines plane. This is more a weight than a fuel issue, but fuel is easier to dump than pax or cargo!
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