Great idea (Score: 0) by Anonymous Coward on 2015-01-08 02:54 (#2WP7) Will it scale to commercial airlines though Re: Great idea (Score: 1) by nightsky30@pipedot.org on 2015-01-09 00:25 (#2WPA) I hope it is, but I doubt we will see any drop in ticket prices. Greedy, all of them! Re: Great idea (Score: 2, Interesting) by bsdguy@pipedot.org on 2015-01-11 03:15 (#2WPD) As a middle class private pilot who owns his own plane (cheap little one) I can tell you there are plenty of costs to aviation which the public does not directly see. Here is a small list from my experience owning a plane for just a few years.. annual inspection (about $400 for my little plane, much more for a 747). 100 hour inspection - yep every plane in commercial service must be inspected every 100 operational hours at about the same level as the annual inspection. landing fees - to land and take off from JFK, LGA, or EWR costs over $100 for my little 2 place plane.fuel of course.lubrication oil.replacement parts for time limited parts - ex a gen-set may be rated at 10,000 hours after which it must be replaced even if in perfect order. mandated engine overhauls - my engine must be given a complete overhaul every 500 operating hours. recurring training for pilots - for private pilots this comes out to something between $500 and $2000 every 2 years, for ATP pilots (airline pilots) the costs are greater and so is the frequency.cost of operating slots at major airports - yep the airlines have to pay for take off and landing times at LGA,JGK, LAX, SFO etc.So while we would all love to see lower costs I can not say it is all due to greed. Something I read several years ago claimed that airlines only made a few percent profit. I have not been part of an airline, but I am friends with owners of small charter operations and I can tell you they have real thin profit margins.From what I see the best use of hybrid technology in aviation is for small general aviation aircraft like mine, and then the small to medium sized puddle jumpers used by the regional operators and charter operations. The technology does not lend it's self well as a replacement for jet propulsion, so the bigger faster planes will not benefit from this work in the foreseeable future.BSDGuy Re: Great idea (Score: 1) by evilviper@pipedot.org on 2015-01-11 05:13 (#2WPJ) The technology does not lend it's self well as a replacement for jet propulsion, so the bigger faster planes will not benefit from this work in the foreseeable future.I'm not so sure... I'd like to see how much more quickly a 787 with electric motors on the landing gear could reach takeoff speeds. Re: Great idea (Score: 0) by Anonymous Coward on 2015-01-11 15:21 (#2WPK) Actually, it doesn't matter when you use the battery energy. LiPo just doesn't have enough energy density to be a viable energy source for big aircraft, especially so for long haul. This is important because fuel consumption is directly affected by the weight of the aircraft. So, if you have a lot of dead batteries on board, you're going to pay for them with fuel.I just looked up the specific energy densities for LiPo and Jet A-1. They are 0.56 vs 43 MJ/kg. There is something like a 80 times difference. Let's say that you replace 100kg of fuel with equivalent batteries. The batteries will weigh 8 tons. This will make you burn 800 kg more fuel than normal, for a short 3 hour flight. I fly 320s and I simply doubled the numbers for A320 to get at 787. It is probably incorrect, but I'm sure it's in the ballpark. For a long flight like 10 hours, you burn 2500 kg more fuel just to carry the dead batteries.I didn't mention a couple of things here: with regular fuel, consumption per hour reduces as the flight progresses and the aircraft becomes lighter. Also, for big electric motors, you will have another weight penalty, probably measured in tons. Electric motors are more efficient than turbofans, but I don't see how that could offset the costs I have mentioned because turbofan engines are also quite efficient, something like 70% IIRC.In order to SAVE fuel using batteries, something drastic needs to be done, such as shutting downengines during cruize or something similarly extraordinary. You could maybe do that with smaller aircraft, but never with a big aircraft like 787.
Re: Great idea (Score: 1) by nightsky30@pipedot.org on 2015-01-09 00:25 (#2WPA) I hope it is, but I doubt we will see any drop in ticket prices. Greedy, all of them! Re: Great idea (Score: 2, Interesting) by bsdguy@pipedot.org on 2015-01-11 03:15 (#2WPD) As a middle class private pilot who owns his own plane (cheap little one) I can tell you there are plenty of costs to aviation which the public does not directly see. Here is a small list from my experience owning a plane for just a few years.. annual inspection (about $400 for my little plane, much more for a 747). 100 hour inspection - yep every plane in commercial service must be inspected every 100 operational hours at about the same level as the annual inspection. landing fees - to land and take off from JFK, LGA, or EWR costs over $100 for my little 2 place plane.fuel of course.lubrication oil.replacement parts for time limited parts - ex a gen-set may be rated at 10,000 hours after which it must be replaced even if in perfect order. mandated engine overhauls - my engine must be given a complete overhaul every 500 operating hours. recurring training for pilots - for private pilots this comes out to something between $500 and $2000 every 2 years, for ATP pilots (airline pilots) the costs are greater and so is the frequency.cost of operating slots at major airports - yep the airlines have to pay for take off and landing times at LGA,JGK, LAX, SFO etc.So while we would all love to see lower costs I can not say it is all due to greed. Something I read several years ago claimed that airlines only made a few percent profit. I have not been part of an airline, but I am friends with owners of small charter operations and I can tell you they have real thin profit margins.From what I see the best use of hybrid technology in aviation is for small general aviation aircraft like mine, and then the small to medium sized puddle jumpers used by the regional operators and charter operations. The technology does not lend it's self well as a replacement for jet propulsion, so the bigger faster planes will not benefit from this work in the foreseeable future.BSDGuy Re: Great idea (Score: 1) by evilviper@pipedot.org on 2015-01-11 05:13 (#2WPJ) The technology does not lend it's self well as a replacement for jet propulsion, so the bigger faster planes will not benefit from this work in the foreseeable future.I'm not so sure... I'd like to see how much more quickly a 787 with electric motors on the landing gear could reach takeoff speeds. Re: Great idea (Score: 0) by Anonymous Coward on 2015-01-11 15:21 (#2WPK) Actually, it doesn't matter when you use the battery energy. LiPo just doesn't have enough energy density to be a viable energy source for big aircraft, especially so for long haul. This is important because fuel consumption is directly affected by the weight of the aircraft. So, if you have a lot of dead batteries on board, you're going to pay for them with fuel.I just looked up the specific energy densities for LiPo and Jet A-1. They are 0.56 vs 43 MJ/kg. There is something like a 80 times difference. Let's say that you replace 100kg of fuel with equivalent batteries. The batteries will weigh 8 tons. This will make you burn 800 kg more fuel than normal, for a short 3 hour flight. I fly 320s and I simply doubled the numbers for A320 to get at 787. It is probably incorrect, but I'm sure it's in the ballpark. For a long flight like 10 hours, you burn 2500 kg more fuel just to carry the dead batteries.I didn't mention a couple of things here: with regular fuel, consumption per hour reduces as the flight progresses and the aircraft becomes lighter. Also, for big electric motors, you will have another weight penalty, probably measured in tons. Electric motors are more efficient than turbofans, but I don't see how that could offset the costs I have mentioned because turbofan engines are also quite efficient, something like 70% IIRC.In order to SAVE fuel using batteries, something drastic needs to be done, such as shutting downengines during cruize or something similarly extraordinary. You could maybe do that with smaller aircraft, but never with a big aircraft like 787.
Re: Great idea (Score: 2, Interesting) by bsdguy@pipedot.org on 2015-01-11 03:15 (#2WPD) As a middle class private pilot who owns his own plane (cheap little one) I can tell you there are plenty of costs to aviation which the public does not directly see. Here is a small list from my experience owning a plane for just a few years.. annual inspection (about $400 for my little plane, much more for a 747). 100 hour inspection - yep every plane in commercial service must be inspected every 100 operational hours at about the same level as the annual inspection. landing fees - to land and take off from JFK, LGA, or EWR costs over $100 for my little 2 place plane.fuel of course.lubrication oil.replacement parts for time limited parts - ex a gen-set may be rated at 10,000 hours after which it must be replaced even if in perfect order. mandated engine overhauls - my engine must be given a complete overhaul every 500 operating hours. recurring training for pilots - for private pilots this comes out to something between $500 and $2000 every 2 years, for ATP pilots (airline pilots) the costs are greater and so is the frequency.cost of operating slots at major airports - yep the airlines have to pay for take off and landing times at LGA,JGK, LAX, SFO etc.So while we would all love to see lower costs I can not say it is all due to greed. Something I read several years ago claimed that airlines only made a few percent profit. I have not been part of an airline, but I am friends with owners of small charter operations and I can tell you they have real thin profit margins.From what I see the best use of hybrid technology in aviation is for small general aviation aircraft like mine, and then the small to medium sized puddle jumpers used by the regional operators and charter operations. The technology does not lend it's self well as a replacement for jet propulsion, so the bigger faster planes will not benefit from this work in the foreseeable future.BSDGuy Re: Great idea (Score: 1) by evilviper@pipedot.org on 2015-01-11 05:13 (#2WPJ) The technology does not lend it's self well as a replacement for jet propulsion, so the bigger faster planes will not benefit from this work in the foreseeable future.I'm not so sure... I'd like to see how much more quickly a 787 with electric motors on the landing gear could reach takeoff speeds. Re: Great idea (Score: 0) by Anonymous Coward on 2015-01-11 15:21 (#2WPK) Actually, it doesn't matter when you use the battery energy. LiPo just doesn't have enough energy density to be a viable energy source for big aircraft, especially so for long haul. This is important because fuel consumption is directly affected by the weight of the aircraft. So, if you have a lot of dead batteries on board, you're going to pay for them with fuel.I just looked up the specific energy densities for LiPo and Jet A-1. They are 0.56 vs 43 MJ/kg. There is something like a 80 times difference. Let's say that you replace 100kg of fuel with equivalent batteries. The batteries will weigh 8 tons. This will make you burn 800 kg more fuel than normal, for a short 3 hour flight. I fly 320s and I simply doubled the numbers for A320 to get at 787. It is probably incorrect, but I'm sure it's in the ballpark. For a long flight like 10 hours, you burn 2500 kg more fuel just to carry the dead batteries.I didn't mention a couple of things here: with regular fuel, consumption per hour reduces as the flight progresses and the aircraft becomes lighter. Also, for big electric motors, you will have another weight penalty, probably measured in tons. Electric motors are more efficient than turbofans, but I don't see how that could offset the costs I have mentioned because turbofan engines are also quite efficient, something like 70% IIRC.In order to SAVE fuel using batteries, something drastic needs to be done, such as shutting downengines during cruize or something similarly extraordinary. You could maybe do that with smaller aircraft, but never with a big aircraft like 787.
Re: Great idea (Score: 1) by evilviper@pipedot.org on 2015-01-11 05:13 (#2WPJ) The technology does not lend it's self well as a replacement for jet propulsion, so the bigger faster planes will not benefit from this work in the foreseeable future.I'm not so sure... I'd like to see how much more quickly a 787 with electric motors on the landing gear could reach takeoff speeds. Re: Great idea (Score: 0) by Anonymous Coward on 2015-01-11 15:21 (#2WPK) Actually, it doesn't matter when you use the battery energy. LiPo just doesn't have enough energy density to be a viable energy source for big aircraft, especially so for long haul. This is important because fuel consumption is directly affected by the weight of the aircraft. So, if you have a lot of dead batteries on board, you're going to pay for them with fuel.I just looked up the specific energy densities for LiPo and Jet A-1. They are 0.56 vs 43 MJ/kg. There is something like a 80 times difference. Let's say that you replace 100kg of fuel with equivalent batteries. The batteries will weigh 8 tons. This will make you burn 800 kg more fuel than normal, for a short 3 hour flight. I fly 320s and I simply doubled the numbers for A320 to get at 787. It is probably incorrect, but I'm sure it's in the ballpark. For a long flight like 10 hours, you burn 2500 kg more fuel just to carry the dead batteries.I didn't mention a couple of things here: with regular fuel, consumption per hour reduces as the flight progresses and the aircraft becomes lighter. Also, for big electric motors, you will have another weight penalty, probably measured in tons. Electric motors are more efficient than turbofans, but I don't see how that could offset the costs I have mentioned because turbofan engines are also quite efficient, something like 70% IIRC.In order to SAVE fuel using batteries, something drastic needs to be done, such as shutting downengines during cruize or something similarly extraordinary. You could maybe do that with smaller aircraft, but never with a big aircraft like 787.
Re: Great idea (Score: 0) by Anonymous Coward on 2015-01-11 15:21 (#2WPK) Actually, it doesn't matter when you use the battery energy. LiPo just doesn't have enough energy density to be a viable energy source for big aircraft, especially so for long haul. This is important because fuel consumption is directly affected by the weight of the aircraft. So, if you have a lot of dead batteries on board, you're going to pay for them with fuel.I just looked up the specific energy densities for LiPo and Jet A-1. They are 0.56 vs 43 MJ/kg. There is something like a 80 times difference. Let's say that you replace 100kg of fuel with equivalent batteries. The batteries will weigh 8 tons. This will make you burn 800 kg more fuel than normal, for a short 3 hour flight. I fly 320s and I simply doubled the numbers for A320 to get at 787. It is probably incorrect, but I'm sure it's in the ballpark. For a long flight like 10 hours, you burn 2500 kg more fuel just to carry the dead batteries.I didn't mention a couple of things here: with regular fuel, consumption per hour reduces as the flight progresses and the aircraft becomes lighter. Also, for big electric motors, you will have another weight penalty, probably measured in tons. Electric motors are more efficient than turbofans, but I don't see how that could offset the costs I have mentioned because turbofan engines are also quite efficient, something like 70% IIRC.In order to SAVE fuel using batteries, something drastic needs to be done, such as shutting downengines during cruize or something similarly extraordinary. You could maybe do that with smaller aircraft, but never with a big aircraft like 787.