This may not apply to all airlines, or apply to today’s world, but I was watching a video on Britannia 226A crash from 1999. In the video, they mentioned that the pilots were under pressure to land, so they wouldn’t have to explain to their bosses why they landed with less than the minimum amount of fuel required.
If a plane takes off, has to abandon a landing attempt, or complete an extra go around, or has to stay in a holding pattern, or has to divert… but they land safely without incident nor issue, why would that be an issue? What else could the pilots do?
Edit to add the answer (thank you for all of the replies, everyone! I misunderstood entirely what the video was attempting to convey): There are aviation safety boards with strict rules and landing with low fuel is grounds for a report and an investigation into the flight, so the safety boards can find the root cause for why the flight did not have an adequate amount of fuel on landing. The pilots may get into trouble if the investigation finds they were at fault, but it is more geared towards safety and attributing a root cause for the issue to make a low fuel event less likely in the future.
In: 707
Consequences of flying with the exact amount of fuel needed for the flight:
https://en.m.wikipedia.org/wiki/LaMia_Flight_2933
It’s a buffer to stop airlines capitalising the shit out of air travel and likely causing emergencies/crashes from running out of fuel in situations of diversions and unforeseen flying conditions.
Like almost all rules – they exist to protect others from stupidity, greed and selfishness.
I’m going to answer your question however, to kind of nitpick your question, from what I’m reading about the accident, it doesn’t sound like the pilots were afraid of company repercussions for running low on fuel. They were actually running low on fuel after attempting the approach.
Anyways, here’s the answer:
So there’s an old adage in aviation, “The only time you have too much fuel is when you’re on fire.”
When it comes to aviation, it is important to make the distinction that there is a planning phase and a reality phase. When planning is done well, pending any surprises en route, the reality phase is usually uneventful and goes according to what was planned.
At airlines, this planning is done well before the flight departs and done by a dispatcher, usually at the company headquarters, sometimes on the other side of the world from where the flight is actually happening. The dispatcher is looking at everything pertinent to that flight with the goal of planning a flight that is cost-effective/profitable for the company but also safe and compliant with regulations. This includes answering questions like: How does the weather look at departure, en route, and at the destination upon arrival time? What routing is efficient but will avoid the most known or forecasted weather/ turbulence, airspace closures, etc? Are there any pieces of equipment on the plane that have been deferred by maintenance that reduce the performance of the airplane and thus require more fuel? All this planning is done to come up with an important answer, how much fuel will be needed to complete this flight?
If it were up to pilots, they would want to carry the max amount of fuel possible every flight, because fuel buys you time when unexpected events happen or in emergencies. The airline wants to minimize the amount of fuel used because it helps keep the cost of operating the flight down. These two desires are at odds with each other and it’s up to the dispatcher to try and make everyone happy. Fortunately, the regulating agencies for aviation, have specific requirements for how much minimum fuel is required for a specific flight. These rules vary by type of operation, domestic or international, VFR (good weather) vs IFR (bad weather) so I’m not going to explain them all now, but, and this is the important part *these rules build the minimum amount of fuel that a dispatcher can legally dispatch the flight with based on all the information he has during the* ***planning phase.*** This completes the planning phase, which is usually completed about an hour prior to departure.
Now we get to the reality phase. The pilots arrive at the airplane and read over the flight plan that the dispatcher created. The pilot in command (PIC) aka, the captain, has to agree to what the dispatcher came up with and sign the flight plan. Maybe since the flight plan was made, the weather forecast changed at the destination or an airplane broke down on the main runway at the destination, and the only suitable runway that was planned to be used might not be open upon arrival. These are all things that are unpredictable and can not be expected to be planned for. All of this is easier to sort out on the ground because, well, you’re still on the ground. While on the ground, if the pilots notice these things, they can call the dispatcher and discuss it with them and come up with a new plan. According to the Wikipedia article about the crash, it looks like this had happened.
>Before taking off from Cardiff, the crew had been briefed on the weather forecast in Girona. The briefing concluded that thunderstorms would be present at the destination airport and all three alternate airports. The crew had ordered an additional 15 minutes of fuel reserve for possible delays.
Once you get in the air though, well, reality is still going to be reality. Things may not go according to the plan the pilots and the dispatcher had on the ground and now you’re at the disadvantage of only having whatever fuel is in your tanks, which is a finite resource and is diminishing with every second.
During planning, extra fuel is required by those regulations, but also the judgment of the dispatcher and pilots too. Either can ADD fuel to the flight plan just in case. In any event, though that buys you some extra time for contingencies that might occur in flight but you will eventually run out of fuel given enough time. It’s here that some pilots get a little confused about the regulations. The requirement for the minimum amount of fuel required to dispatch a flight is only during the **planning phase.** Once in the air, although not a great idea, the pilots can use every bit of fuel they have to land. Most pilots will have a minimum amount of fuel that they feel comfortable landing with and if they get close to that number, will make a decision about continuing or diverting. When you do run low on fuel (usually considered to be less than 30 min remaining) there are requirements in flight like declaring to air traffic control that you have “min fuel” or taking it a step further and declaring an outright emergency but there is not a hard amount of fuel required to be in the tanks on landing. Don’t get me wrong, if you land with what is well below what would be a normal arrival fuel, your airline (or union)’s safety department might want some more information about why that happened, but legally there is no amount of fuel required to be in the tanks upon landing. The only time a specific amount is required to be in the tanks is during planning.
Fuel is a surprisingly relavent portion of the plane’s total weight. A full tank is heavier and thus less fuel efficient.
Probably not the case in this flight, but jet aircraft use fuel to cool down hydraulic fluid and engine oil. There is a small radiator in the fuel tank that oil and hydraulic fluid flows through to to cool it down. It needs to be submerged in fuel, otherwise it won’t get proper cooling. The biggest danger is called a thermal disconnect, if the generators get too hot a mechanical fuse made of solder will melt which prevents them generator from spinning in order to prevent a fire.
I was once on a flight from Frankfurt to Toronto. When we got to Toronto, the weather was bad so we circled for close to an hour … then we flew to Montreal and landed (then took an 8 hour bus ride from Montreal to Toronto! It was a school trip and I guess paying for 30 kids to stay in a hotel in Montreal was out of the question versus shoving us on a greyhound bus and sending us home).
Without the extra fuel for an extra three hours of flight, what are your options?
I think it’s a common misconception or misinterpretation of the rules that say you must take off with enough fuel to reach your destination, then depending on whether they filed IFR or VFR, land with 45 minutes or 30 minutes of fuel remaining.
It’s not a violation to land with less than the minimum required fuel, as long as you took off with the appropriate amount. Obviously, pilots are hesitant to land with less, because you don’t want to run out.
I’m not familiar with the case you’re talking about, but if the pilots were worried about getting into trouble for landing with less than the required minimums for reasons beyond their control, they didn’t understand the rule, or they had unnecessary pressure being placed on them by their management.
Edit: as pointed out, I clearly applied US rules to what sounds like a British airline. YMMV.
I’m an airline pilot. Unexpected things happen constantly. Delays getting into the airport, unforecasted weather, runway closures, stronger headwinds than anticipated, having to do a go-around, etc. We’re required by law to have 45 minutes (USA rules) of extra fuel on board to account for any extra delays that might happen. If the weather isn’t ideal, we also have to bring extra fuel to divert to an alternate airport, plus another 45 minutes after we get there. I frequently bring extra fuel on top of this because I feel like 45 minutes isn’t enough. Airlines sometimes don’t like this because bringing extra fuel means you burn more fuel ($$$) since you’re heavier, but as a Captain they will give you the extra gas anyway if you insist.
A lot of people here have given you your answer. If nothing else, it feels sketchy as Hell flying with less than 30 minutes of fuel. Crossing your fingers that everything goes right is awful.
Because some smart guy/gal figured out that flying with more than you need costs the airlines $$$.
Its like having 2 ketchup bottles in the fridge taking up precious room but you never need 2!
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