How much spare fuel does a typical aircraft have?

Kenai

Kenai

Kenai

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Just been out walking the dog and there are 6 or 7 planes circling in a holding pattern for Southampton Airport, where it doesn't appear anything has landed since 8.52.

Some of the flights appear to have been circling the best part of an hour looking at flightradar

How long can they keep that up before they have to go elsewhere?

Southampton will only accept flights until 11pm anyway I think, so they'll have to go somewhere else soon if they can't land here!
 
Kenai said:
Just been out walking the dog and there are 6 or 7 planes circling in a holding pattern for Southampton Airport, where it doesn't appear anything has landed since 8.52.

Some of the flights appear to have been circling the best part of an hour looking at flightradar

How long can they keep that up before they have to go elsewhere?

Southampton will only accept flights until 11pm anyway I think, so they'll have to go somewhere else soon if they can't land here!
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They’ll only accept scheduled flights until 11pm. Unsure on the fuel but there is a minimum amount which unsurprisingly Ryanair push to the limit.
 
Apparently it's just because of fog, so nothing exciting but I am interested in how long they could keep circling before having to give up and go somewhere else. An hour of circling on hour to hour and a half long flights is near enough doubling the time in the air.
 
I’m sure we’ll get an airline pilot or two answer but it’s enough to hold for x time and then divert to the alternative they have specified plus a little extra.

They certainly don’t always fly with full tanks, that would be a waste of money.
 
Feek said:
I’m sure we’ll get an airline pilot or two answer but it’s enough to hold for x time and then divert to the alternative they have specified plus a little extra.

They certainly don’t always fly with full tanks, that would be a waste of money.
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Not to mention a 'bit risky' if there's an incident on landing.
 
Roland Butter said:
I thought every commercial passenger aircraft had full tanks , even if it was only flying from Glasgow to Dublin.
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Full tanks mean more weight, more weight means more fuel used to maintain flight.

More fuel used = more cost both monetary and environmentally.
 
Im sure I read before that Ryanair were well known for targeting pilots on fuel usage, which led to a number of aircraft declaring fuel emergencies and skipping landing queues.

They were expected to load as little as possible to save money and some even suspected that fuel emergencies were being declared when not needed simply to help with a pilots fuel usage...

I do believe that Pilots use passenger numbers, baggage weights, route options, weather and other factors when calculating how much fuel they need at the start of each flight. So they are in charge of it, and would be expected to load sensibly and safely.
 
Resident said:
Full tanks mean more weight, more weight means more fuel used to maintain flight.

More fuel used = more cost both monetary and environmentally.
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Indeed, but airlines are in the business of not killing passengers unnecessarily if they can help it, there must be a safety margin fuel wise,
you can't fill the tanks with just enough fuel to fly a 2000 mile journey without a contingency for calamity, what happens if, say,
the landing gear refuses to lock and the pilot needs an extra 2 hours flying time to liaise with tech support and fix the problem, or
say, New York is being attacked by terrorists so all planes must land at Gander, Newfoundland, Canada, oh hold on, that actually did happen.
 
It's calculated as described a few posts up, they don't fill by default.

I flew on a small aircraft on Thursday night. Just as the pilot revved the engines to max prior to taxiing, they just abruptly shut down. He then angrily declared that he'd need to switch the aircraft off and back on again to "see if that would work".

It worked. And so did my sphincter for the duration of the flight. :eek:
 
Roland Butter said:
Indeed, but airlines are in the business of not killing passengers unnecessarily if they can help it, there must be a safety margin fuel wise
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There is, but Resident was telling you why the airlines don't just "fill her up" for every flight regardless of Long haul or Short (which was what you asked and he was replying to). For example most short to medium haul flights don't need (even with a fuel safety margin) to be fully fuelled as shown below whilst most Long haul flights are filled to the brim and will have a fuel stop just to increase the safety margin.

Some examples -

Airbus A320 Short Haul range with full tanks is around 3800 miles (3300nm) whilst a Heathrow to Manchester flight flies 300 miles (260nm) - so for short haul it's just not needed.
Boeing 787 Medium Haul range with full tanks is around 8800 miles (7600nm) whilst a Manchester to Jeddah, Saudi Arabia flight flies 3100 miles (2700nm) - So still short enough that full tanks aren't required.
Boeing 777-200LR Haul range with full tanks is around 11000 miles (9500nm) whilst a Manchester to Sydney flight flies 10500 miles (9100nm) - so that would be filled to brim and, for safety, would stop for a refuel stop somewhere around 3/4 of the distance.

EDIT - This "range vs fuel" difference caused the Hijackers of Ethopian Flight 961 to crash the plane into the ocean as they wanted the pilot to fly to Australia (within the max range) whilst the fuel load wasn't able to do that, so it ran out of fuel and crashed - https://en.wikipedia.org/wiki/Ethiopian_Airlines_Flight_961
 
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Roland Butter said:
Indeed, but airlines are in the business of not killing passengers unnecessarily if they can help it, there must be a safety margin fuel wise,
you can't fill the tanks with just enough fuel to fly a 2000 mile journey without a contingency for calamity, what happens if, say,
the landing gear refuses to lock and the pilot needs an extra 2 hours flying time to liaise with tech support and fix the problem, or
say, New York is being attacked by terrorists so all planes must land at Gander, Newfoundland, Canada, oh hold on, that actually did happen.
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I've already answered everything you've mentioned.
 
My friend us a flight planner for DHL and I've spoken to him about this before, trying to remember what he said.

It's something along the lines of
Fuel required for planned flight + contingency + required fuel to get to secondary airport (perhaps even + safety margin)

Airlines want to reduce weight at almost any way possible as increased weight requires more fuel which is further increased cost.
 
I have the flight sim software to calculate all this if anyone really wants to know the exact extra fuel for a certain type of aircraft and the dep/arr/alt airport based on the current weather,
 
Fuel for journey to destination
+
Fuel to alternate diversion airport
+
Specified hold time (eg 45 mins)
+
5% final reserve

(from my days of flight simming, not a pilot)
 
String said:
It's calculated as described a few posts up, they don't fill by default.

I flew on a small aircraft on Thursday night. Just as the pilot revved the engines to max prior to taxiing, they just abruptly shut down. He then angrily declared that he'd need to switch the aircraft off and back on again to "see if that would work".

It worked. And so did my sphincter for the duration of the flight. :eek:
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I had a similar thing ince where they declared the take off would be delayed while they investigated a faulty engine. But they hoped it would be nothing tmand we would take off soon :eek
 
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