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> No U.S airlines currently fly into any Russian cities, and those that flew over Russia's vast airspace to Asia had already been rerouting out of an abundance
by Scoundreller 5y ago
> No U.S airlines currently fly into any Russian cities, and those that flew over Russia's vast airspace to Asia had already been rerouting out of an abundance of caution. That adds time and burns a lot more fuel, increasing costs.
Yes and no. If you add a refueling stop to a long-haul flight, it can save enough fuel to make up for the rerouting. (Long-haul flying is really inefficient because you have to take-off/carry all the fuel needed to make it to your destination).
e.g. a flight from NYC-Paris-Delhi is only 5.5% longer distance than direct, even though it now routes over europe instead of a direct polar route over Russia
http://www.gcmap.com/mapui?P=nyc-del,+nyc-cdg-del http://www.gcmap.com/mapui?P=nyc-del,+nyc-cdg-del
(This isn't perfect, it still shows a bit of routing over Russia, but you get the idea). And you still have staffing costs, landing costs, etc. Weather related routings, night-time landing restrictions, etc.
- messe 5y ago> Yes and no. If you add a refueling stop to a long-haul flight, it can save enough fuel to make up for the rerouting. (Long-haul flying is really inefficient because you have to take-off/carry all the fuel needed to make it to your destination). It seems obvious, but I always forget that the rocket equation applies in aviation as well. The massive difference in fuel efficiencies when you get your oxidizer for free tends to overshadow it.
- Scoundreller 5y agoAnd using smaller airframes (because you can run smaller/lighter fuel tanks, along with lower drag) can add to those efficiency gains: > the total fuel consumption of a 7,200 NM flight can be reduced by up to 15% by making an intermediate stop half way, while using conventional existing long-haul aircraft. When the aircraft is specifically designed for medium-range operations (such as e.g. the Airbus A300), the total fuel savings could increase to 27%. From: "Evaluation of intermediate stop operations in long-haul flights" NYC to Delhi is at 6400 NM.
- sigmoid10 5y agoThe rocket equation doesn't apply here, because planes don't just get their oxidizer for free, they get the whole reaction mass as well. So they generate forward momentum in a different way. Additionally, once a plane reaches cruising altitude, the only energy losses are due to air resistance, because the lift vector from the wings and the gravitational pull are antiparallel to each other and perpendicular to the direction of motion. The commenter above is still correct though, because the energy needed during ascent is proportional to mass times height. So if you can cut the fuel in half by limiting the total range, you can save a huge amount of energy (i.e. fuel) during ascent.
- newaccount74 5y agoA plane is not a satellite. You need to constantly expend energy to keep it in the air. The more weight is on the plane, the more lift you need. To get a bigger lift, you need to angle the control surfaces steeper, which increases drag. Therefore transporting heavy things by air (like fuel) is extremely inefficient.
- Rebelgecko 5y agoI think that's part of why Anchorage is one of the busiest airports in the world
- Scoundreller 5y agoIt really helps for the cargo airlines operating 'old' inefficient aircraft. E.g. 747s And you can load them up more when you only have to half-fill the fuel tanks.