Battery powered Skyhawk
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Battery powered Skyhawk
It has been seldom in the history of aviation that a single technology has revolutionized the way we fly by addressing multiple problems facing the industry and solving them all. The most important such event was the widescale adoption of the turbine engine in the 1940s. Turbines, as you know, remedied (and continue to remedy) commercial, military and business aviation problems of reliability, cost, range, speed and power, while also bringing with them a number of infrastructure advantages associated with using a single fuel type. Though it’s still in its infancy, electric propulsion seems to promise to solve a similar range of problems in light GA. But in the case of the electric motor, the potential advances might be more sweeping and more compelling, though almost certainly on a smaller scale economically.
The most visible electric airplane project these days is Bye Energy’s Green Flight Project. The man behind the program is George Bye, an engineer whose background as an Air Force transport pilot and instructor doesn’t seem to lend itself to his new role as a high-tech entrepreneur and self-described futurist, the head of a company that is trying to do no less than bring electric power to the mainstream of light general aviation.
Bye has even bigger ideas for Green Flight, but the first step for his company is nevertheless an ambitious one: to convert the most popular airplane in history, the Cessna Skyhawk, to electric power. On Bye’s team is a guy who certainly knows Skyhawks, former Cessna CEO Charlie Johnson. Bye and Johnson gave a product update on the Green Flight Project at a press conference during the AOPA Summit in Long Beach, California, in November. There was much promising news, including endorsements and partnerships with several industry heavy hitters, such as Jeppesen and Cessna. Now nearly done with the detailed engineering phase of the project, Bye Energy could be flying the first electric Skyhawk soon.[...]
A Battery-Powered Skyhawk - Pilot Magazin
The most visible electric airplane project these days is Bye Energy’s Green Flight Project. The man behind the program is George Bye, an engineer whose background as an Air Force transport pilot and instructor doesn’t seem to lend itself to his new role as a high-tech entrepreneur and self-described futurist, the head of a company that is trying to do no less than bring electric power to the mainstream of light general aviation.
Bye has even bigger ideas for Green Flight, but the first step for his company is nevertheless an ambitious one: to convert the most popular airplane in history, the Cessna Skyhawk, to electric power. On Bye’s team is a guy who certainly knows Skyhawks, former Cessna CEO Charlie Johnson. Bye and Johnson gave a product update on the Green Flight Project at a press conference during the AOPA Summit in Long Beach, California, in November. There was much promising news, including endorsements and partnerships with several industry heavy hitters, such as Jeppesen and Cessna. Now nearly done with the detailed engineering phase of the project, Bye Energy could be flying the first electric Skyhawk soon.[...]
A Battery-Powered Skyhawk - Pilot Magazin
Sorry, flysebi, but this is all too reminiscent of the novel "Lijmen" by my countryman Willem Elsschot, translated into English as "Soft Soap".
Of all construction materials, steel is the noblest, the most....
("steel" replaced by marble, glass, wood, cardboard, or whatever fitted the new victim)
Of all construction materials, steel is the noblest, the most....
("steel" replaced by marble, glass, wood, cardboard, or whatever fitted the new victim)
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Why get a Skyhawk electric powered?
No-one in their right minds is trying to get an existing motor vehicle made all-electric.
No-one would put a turbine on a Spitfire.
New powerplants mean new airframes.
And airframe technology has leapt ahead huge amounts since the days of the SkyHawk!
No-one in their right minds is trying to get an existing motor vehicle made all-electric.
No-one would put a turbine on a Spitfire.
New powerplants mean new airframes.
And airframe technology has leapt ahead huge amounts since the days of the SkyHawk!
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Hot air powered Skyhawk - almost nearly ready, maybe
Having been on the receiving end of this sort of PR-speak drivel for the past 30 years, I had almost lost the will to live by the tenth word.
By the way, I'm currently working on a new engine design which works on rice-pudding, sucks carbon dioxide out of the atmosphere and turns it into fresh spring water with a hint of lemon - all I need is to get some industry big hitters on-side and I can start the ball rolling.
Gimme a break
By the way, I'm currently working on a new engine design which works on rice-pudding, sucks carbon dioxide out of the atmosphere and turns it into fresh spring water with a hint of lemon - all I need is to get some industry big hitters on-side and I can start the ball rolling.
Gimme a break
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I think it's a marvelous idea. Purchase and maintenance costs on an electric motor are going to be hugely reduced over those of a gasoline engine, necessary electricity costs will be drastically lower than fuel costs of gasoline-powered Skyhawks, and once all the teething issues are solved, an electric motor will be much more reliable than an internal combustion engine.
Those of you bucking over this because it's different need to accept that progress requires setting aside some things we've grown to be comfortable with and moving onto newer and better things.
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I know a leetle bit about this technology and i think the weight and size of any 'fuel cell' would be prohibitive to the design, the amount of charge you would get from a series of solar cells would not nearly be enough to power a 134KW engine, it may run your glass panel nicely though.
Putting the technology in a new airframe designed around this technology is a new ball game, i think the detractors are talking more about using an existing inefficient airframe design.
If you look at electric or hybrid cars you can see the amount of space taken up by the fuel cells not to mention the weight, on the ground this is not an issue, in an light Aircraft, these things are at a premium.
Solar power is useful to a point, i know its limitations it powers a bunch of my instruments (weather sensors and station) but its not nearly enough to power my irrigation systems which has much less draw than 134 KW!!!!
Putting the technology in a new airframe designed around this technology is a new ball game, i think the detractors are talking more about using an existing inefficient airframe design.
If you look at electric or hybrid cars you can see the amount of space taken up by the fuel cells not to mention the weight, on the ground this is not an issue, in an light Aircraft, these things are at a premium.
Solar power is useful to a point, i know its limitations it powers a bunch of my instruments (weather sensors and station) but its not nearly enough to power my irrigation systems which has much less draw than 134 KW!!!!
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I know a leetle bit about this technology and i think the weight and size of any 'fuel cell' would be prohibitive to the design, the amount of charge you would get from a series of solar cells would not nearly be enough to power a 134KW engine, it may run your glass panel nicely though.
Putting the technology in a new airframe designed around this technology is a new ball game, i think the detractors are talking more about using an existing inefficient airframe design.
If you look at electric or hybrid cars you can see the amount of space taken up by the fuel cells not to mention the weight, on the ground this is not an issue, in an light Aircraft, these things are at a premium.
Solar power is useful to a point, i know its limitations it powers a bunch of my instruments (weather sensors and station) but its not nearly enough to power my irrigation systems which has much less draw than 134 KW!!!!
Putting the technology in a new airframe designed around this technology is a new ball game, i think the detractors are talking more about using an existing inefficient airframe design.
If you look at electric or hybrid cars you can see the amount of space taken up by the fuel cells not to mention the weight, on the ground this is not an issue, in an light Aircraft, these things are at a premium.
Solar power is useful to a point, i know its limitations it powers a bunch of my instruments (weather sensors and station) but its not nearly enough to power my irrigation systems which has much less draw than 134 KW!!!!
Also, how often do most of us fly with more than 1 passenger in a 172, or for the full range of the airplane? For the type of flying most weekend pilots do, I think a weight and range penalty would not be much of an issue.
In any case, this is a stepping stone toward better, more advanced aircraft that build upon this technology.
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Electric has a great future for aviation. It solves virtually all the problems we have with propulsion whilst delivering more power-to-weight than any other prime mover (much more than turbines).
It's the energy storage that's still the bottleneck, as you know. But it's advancing in leaps and bounds. Already today, weight for weight, you could get 1 hr endurance out out of an electric 172. That's pretty impressive. With a lighter airframe and advances in energy storage, you could see 3hrs pretty soon.
You might want to look at a thread I started a while ago on the subject:
http://www.pprune.org/private-flying...-aircraft.html
It's the energy storage that's still the bottleneck, as you know. But it's advancing in leaps and bounds. Already today, weight for weight, you could get 1 hr endurance out out of an electric 172. That's pretty impressive. With a lighter airframe and advances in energy storage, you could see 3hrs pretty soon.
You might want to look at a thread I started a while ago on the subject:
http://www.pprune.org/private-flying...-aircraft.html
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I know a leetle bit about this technology and i think the weight and size of any 'fuel cell' would be prohibitive to the design, the amount of charge you would get from a series of solar cells would not nearly be enough to power a 134KW engine, it may run your glass panel nicely though.
Putting the technology in a new airframe designed around this technology is a new ball game, i think the detractors are talking more about using an existing inefficient airframe design.
If you look at electric or hybrid cars you can see the amount of space taken up by the fuel cells not to mention the weight, on the ground this is not an issue, in an light Aircraft, these things are at a premium.
Solar power is useful to a point, i know its limitations it powers a bunch of my instruments (weather sensors and station) but its not nearly enough to power my irrigation systems which has much less draw than 134 KW!!!!
Putting the technology in a new airframe designed around this technology is a new ball game, i think the detractors are talking more about using an existing inefficient airframe design.
If you look at electric or hybrid cars you can see the amount of space taken up by the fuel cells not to mention the weight, on the ground this is not an issue, in an light Aircraft, these things are at a premium.
Solar power is useful to a point, i know its limitations it powers a bunch of my instruments (weather sensors and station) but its not nearly enough to power my irrigation systems which has much less draw than 134 KW!!!!
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Electricity has no future in aircraft until the storage issue is sorted. The shear energy density of combustible fuels is orders of magnitude greater than the best (read very very expensive) storage solution we current have.
Specialist airframes - such a self launching gliders - can use what we presently have - until the cells get old and then their replacement costs make overhauling a Lycon seem like small change.
It all looks a very long way off unless there is a major break through in storage technology.
As for converting a Cessna 172? Why on earth would you pick that airframe for a technology which is challenged on payload, endurance and power?
Specialist airframes - such a self launching gliders - can use what we presently have - until the cells get old and then their replacement costs make overhauling a Lycon seem like small change.
It all looks a very long way off unless there is a major break through in storage technology.
As for converting a Cessna 172? Why on earth would you pick that airframe for a technology which is challenged on payload, endurance and power?
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The first post seems like an advertisment for a magazine with that article in it.
I like the thoughts of electric aircraft, but have some reservations.
Energy storage is one that has been mentioned. An endurance of <3 hours isn't enough. Any electric aircraft that I've heard about has a relatively slow speed (100mph or less). I would never be comfortable planning a flight with less than 1 hour reserves, which means I'd be limited to <200 miles.
On top of this, electric motors seem to slow down as fuel supply gets lower, rather than running normally until exhaused like combustion engines.
A second issue is shrinking fuel tanks! We all know that our laptops run for shorter and shorter periods on batteries as they get older. I don't know if aircraft batteries are the same technology, but I'd be uncomfortable with 'fuel tanks' that were getting smaller as time goes one.....exactly how much fuel do I have before I take off?
However the biggest one for me would be refueling. If I want to go somewhere beyond 100 miles, and return home afterwards, or go further than 200 miles in a single day, then I need to either exchange or recharge the batteries.
Recharging the batteries will take hours, which isn't really acceptable.
Exchanging the batteries means that you are taking on a battery of unknown quality, and unknown fuel content (back to shrinking tanks...how much has this one shrunk by?)
If you never fly more than 80 miles away, then most of these problems aren't for you, but would you really buy an aircraft with such a range limitation?
dp
I like the thoughts of electric aircraft, but have some reservations.
Energy storage is one that has been mentioned. An endurance of <3 hours isn't enough. Any electric aircraft that I've heard about has a relatively slow speed (100mph or less). I would never be comfortable planning a flight with less than 1 hour reserves, which means I'd be limited to <200 miles.
On top of this, electric motors seem to slow down as fuel supply gets lower, rather than running normally until exhaused like combustion engines.
A second issue is shrinking fuel tanks! We all know that our laptops run for shorter and shorter periods on batteries as they get older. I don't know if aircraft batteries are the same technology, but I'd be uncomfortable with 'fuel tanks' that were getting smaller as time goes one.....exactly how much fuel do I have before I take off?
However the biggest one for me would be refueling. If I want to go somewhere beyond 100 miles, and return home afterwards, or go further than 200 miles in a single day, then I need to either exchange or recharge the batteries.
Recharging the batteries will take hours, which isn't really acceptable.
Exchanging the batteries means that you are taking on a battery of unknown quality, and unknown fuel content (back to shrinking tanks...how much has this one shrunk by?)
If you never fly more than 80 miles away, then most of these problems aren't for you, but would you really buy an aircraft with such a range limitation?
dp
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gasax wrote:
---------------
"Electricity has no future in aircraft until the storage issue is sorted. The shear energy density of combustible fuels is orders of magnitude greater than the best (read very very expensive) storage solution we current have.
Specialist airframes - such a self launching gliders - can use what we presently have - until the cells get old and then their replacement costs make overhauling a Lycon seem like small change.
It all looks a very long way off unless there is a major break through in storage technology.
As for converting a Cessna 172? Why on earth would you pick that airframe for a technology which is challenged on payload, endurance and power?"
--------------
I have an electric-powered modification on order for my glider.
Battery life is estimated as 1000 recharges before they deteriorate to 80 percent capacity. Say 100 per year for 10 years. I don't know the future cost of replacement batteries, but say £10,000 in 2021. So I am calling each use of the batteries as costing £10 per flight on which they are used. Not unreasonable. Electricirty recharge cost is negligible by comparison – but say £1 for a 1-hour usage.
Other marginal costs of flying with the FES (Front Electrical sustainer) include higher insurance and maybe some maintenance costs, but I doubt it comes to another £9 per hour of use, so my total “powered” cost is probably going to be below £20 per hour.
Previously, it was an unpowered pure glider, so this is all extra. If I were taking out an IC engine and replacing it with electric, it would be closer to a breakeven – maybe even cheaper, but I will never know.
For heavier aircraft and/or needing more endurance, I would agree that it needs a leap in storage technology. I have no idea how practical that is – but history suggests that tech improvements in future are unforeseeable, though they eventually yield increases of hundreds, or even thousands, of percent in performance.
Chris N.
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"Electricity has no future in aircraft until the storage issue is sorted. The shear energy density of combustible fuels is orders of magnitude greater than the best (read very very expensive) storage solution we current have.
Specialist airframes - such a self launching gliders - can use what we presently have - until the cells get old and then their replacement costs make overhauling a Lycon seem like small change.
It all looks a very long way off unless there is a major break through in storage technology.
As for converting a Cessna 172? Why on earth would you pick that airframe for a technology which is challenged on payload, endurance and power?"
--------------
I have an electric-powered modification on order for my glider.
Battery life is estimated as 1000 recharges before they deteriorate to 80 percent capacity. Say 100 per year for 10 years. I don't know the future cost of replacement batteries, but say £10,000 in 2021. So I am calling each use of the batteries as costing £10 per flight on which they are used. Not unreasonable. Electricirty recharge cost is negligible by comparison – but say £1 for a 1-hour usage.
Other marginal costs of flying with the FES (Front Electrical sustainer) include higher insurance and maybe some maintenance costs, but I doubt it comes to another £9 per hour of use, so my total “powered” cost is probably going to be below £20 per hour.
Previously, it was an unpowered pure glider, so this is all extra. If I were taking out an IC engine and replacing it with electric, it would be closer to a breakeven – maybe even cheaper, but I will never know.
For heavier aircraft and/or needing more endurance, I would agree that it needs a leap in storage technology. I have no idea how practical that is – but history suggests that tech improvements in future are unforeseeable, though they eventually yield increases of hundreds, or even thousands, of percent in performance.
Chris N.
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Battery life is estimated as 1000 recharges before they deteriorate to 80 percent capacity. Say 100 per year for 10 years. I don't know the future cost of replacement batteries, but say £10,000 in 2021. So I am calling each use of the batteries as costing £10 per flight on which they are used. Not unreasonable.
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I am not an expert, but I am told they will, if properly looked after (recharged after each use by a correctly designed balancing charger).
From:
Future of gliding - Front Electric Sustainer
----------------
“A 1200W programable Li-Po charger is used for charging, together with active balancer unit. Balancer monitors the voltage of each cell in the pack and balance them all the time during charging, so that all cells are at same voltage with precision of 0,005V. Balancer could be used even when charger is not turn on. With active balancer, balancing is more precise and faster.
Charging time of one pack of batteries is only 2,5 hours if they are fully discharged. If you used only 50% than charging time is also 50% shorter. LiPo batteries are without memory efect, so you can charge them also if they are not fully discharged!
Unlike lead acid batteries, Li-Po batteries can be stored for months without significantly losing charge. Self discharge rate is less then 1% per month at room temperature!
At 1C rating (horizonatal flight) life expectancy of batteries is around 1500 charging cycles of maximum alowed discharged cells. After that the battery will still have 80% of the original capacity.”
-------------
Chris N
From:
Future of gliding - Front Electric Sustainer
----------------
“A 1200W programable Li-Po charger is used for charging, together with active balancer unit. Balancer monitors the voltage of each cell in the pack and balance them all the time during charging, so that all cells are at same voltage with precision of 0,005V. Balancer could be used even when charger is not turn on. With active balancer, balancing is more precise and faster.
Charging time of one pack of batteries is only 2,5 hours if they are fully discharged. If you used only 50% than charging time is also 50% shorter. LiPo batteries are without memory efect, so you can charge them also if they are not fully discharged!
Unlike lead acid batteries, Li-Po batteries can be stored for months without significantly losing charge. Self discharge rate is less then 1% per month at room temperature!
At 1C rating (horizonatal flight) life expectancy of batteries is around 1500 charging cycles of maximum alowed discharged cells. After that the battery will still have 80% of the original capacity.”
-------------
Chris N
Last edited by chrisN; 15th Mar 2011 at 13:57.
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Electricity has no future in aircraft until the storage issue is sorted.
The best anybody can do at present is chip away around the edges, addressing specialist applications. There is no way to make even a practical electric car.
Also there is no apparent way to make a battery which is recharged quickly.
The best brains around are flat out working on this issue and have been for many years.
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Well, I think it's unfair to immediately demand higher speed, less cost, more endurance from this new technology out of the gate. Of course it will take many years, just like it took 100 years of combustion technology to get to here (well, if you're Lyco or Conti, just 50 years, as nothing has happened to their engines since then...). And in the meantime, we'll probably see many bridging hybrid solutions.
Electric will of course first start in easier applications - such as self launching gliders. There it already makes much more sense than anything else. After that it will be local training aircraft that depart and return to the same airfield, probably with exchangeable fuel cells for speed. What's wrong with cheaper flight instruction?
Once again, you just have to look at hybrid cars - 10 years ago it was something nobody wanted. Now show me a single manufacturer who hasn't got some kind of hybrid in the works? Even Ferrari and Koenigsegg have them in development...
Electric will of course first start in easier applications - such as self launching gliders. There it already makes much more sense than anything else. After that it will be local training aircraft that depart and return to the same airfield, probably with exchangeable fuel cells for speed. What's wrong with cheaper flight instruction?
Once again, you just have to look at hybrid cars - 10 years ago it was something nobody wanted. Now show me a single manufacturer who hasn't got some kind of hybrid in the works? Even Ferrari and Koenigsegg have them in development...
Last edited by AdamFrisch; 15th Mar 2011 at 19:09.
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I like the idea of a "Hybrid" system which uses the electric motor on take off to assist the (smaller?) engine. Loads of torque. No need to carry heaps of stored energy just for a take off/go around.
The real aviation benefit would be the redundancy offered by the electric motor should the engine fail in flight, sure would be nice to be able to maintain airborne for even 15 minutes to make a precautionary landing rather than a forced one!
With some clever technology might it even be possible to let the descent phase recharge the battery a bit? A bit like regenerative braking?
It would be a start, and i believe in starts!
The real aviation benefit would be the redundancy offered by the electric motor should the engine fail in flight, sure would be nice to be able to maintain airborne for even 15 minutes to make a precautionary landing rather than a forced one!
With some clever technology might it even be possible to let the descent phase recharge the battery a bit? A bit like regenerative braking?
It would be a start, and i believe in starts!
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Well, I think it's unfair to immediately demand higher speed, less cost, more endurance from this new technology out of the gate. Of course it will take many years, just like it took 100 years of combustion technology to get to here (well, if you're Lyco or Conti, just 50 years, as nothing has happened to their engines since then...). And in the meantime, we'll probably see many bridging hybrid solutions.
Electric will of course first start in easier applications - such as self launching gliders. There it already makes much more sense than anything else. After that it will be local training aircraft that depart and return to the same airfield, probably with exchangeable fuel cells for speed. What's wrong with cheaper flight instruction?
Once again, you just have to look at hybrid cars - 10 years ago it was something nobody wanted. Now show me a single manufacturer who hasn't got some kind of hybrid in the works? Even Ferrari and Koenigsegg have them in the development...
Electric will of course first start in easier applications - such as self launching gliders. There it already makes much more sense than anything else. After that it will be local training aircraft that depart and return to the same airfield, probably with exchangeable fuel cells for speed. What's wrong with cheaper flight instruction?
Once again, you just have to look at hybrid cars - 10 years ago it was something nobody wanted. Now show me a single manufacturer who hasn't got some kind of hybrid in the works? Even Ferrari and Koenigsegg have them in the development...
Any new technology is not going to be perfect right off the bat. Cars made huge changes in their first 100 years. Computers made huge changes in their first 50 years. Airplanes made huge changes in their first 100 years. Television... Trains... Wind Turbines... Solar Cells... Jet Propulsion... Elevators... Etc...
New technologies take time to grow and improve from the initial concept/prototype phase, but without a first step you get nowhere.
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Hands up now all those who bought a Prius, do you feel like a tit?
The biggest have in automotive history.... with the exception of the PT Cruiser (hey want an older looking new car... heres one we mangled earlier) you burn exactly how much less fuel a year... a thimble... well done
, unless you just bimble to shops it useless... I'm all for planet saving gadgets but don't put a pigs ear in a box and sell me a purse.
When you can do a X-country land and 're-fuel' at a remote airfeild- (an extension cord will do) then i'd be interested.
but why oh why put this technology into and airframe designed 50+ years ago. take advantage of the advances in composites and aerodynamics, build somethign really slippery, then you'd save a lot more power than dragging an in-effecient airframe through the sky.
The biggest have in automotive history.... with the exception of the PT Cruiser (hey want an older looking new car... heres one we mangled earlier) you burn exactly how much less fuel a year... a thimble... well done
, unless you just bimble to shops it useless... I'm all for planet saving gadgets but don't put a pigs ear in a box and sell me a purse.When you can do a X-country land and 're-fuel' at a remote airfeild- (an extension cord will do) then i'd be interested.
but why oh why put this technology into and airframe designed 50+ years ago. take advantage of the advances in composites and aerodynamics, build somethign really slippery, then you'd save a lot more power than dragging an in-effecient airframe through the sky.