AVIATION'S NEW ERA
PART II
Chapter 9. Batteries and Overcoming Limitations
Today’s electric vehicles are significantly limited by the weights and capacities of batteries. Those old limits do not apply to Towed Platform aircraft due to the following methods of overcoming these limitations: a) altitude energy storage, b) towed power platforms, c) refueler aircraft, and d) increase efficiency.
a) Altitude Energy Storage – HAPS/HALE aircraft fly at up 70,000 ft (or more) and are able to glide at night from 70,000 ft to 30,000 ft as a means to recover energy stored in altitude during the day. Both higher speeds and higher L/D enable even further maximum altitudes. This type of storage takes no additional weight and is very efficient in recovery.
The application is toward the effective use of aircraft operating 24/7 in transcontinental flight. The first leg of such trips is with Earth’s rotation and under direct solar power. The second half is against Earth’s rotation. Against Earth’s rotation, the first leg of the trip includes storing potential energy in altitude during evening daylight, while the second half uses stored energy and is at nights that might be shortened in duration by up to 50%. Here the vast majority of 24/7 operation can be achieved without battery-powered propulsion.
The Towed Platform aircraft are capable of higher speeds and higher L/D than the HAPS/HALE benchmarks. This translates to even higher altitude capabilities, which further expands applications.
An important sidenote is that most contemporary aircraft can achieve significantly improved efficiencies by using flat plate lift surfaces on upper and lower surfaces of aircraft. And so, this approach is not limited to “thin” Towed Platform airframes.
b) Towed Power Platforms – In some applications, the payload may not be susceptible to towed platform configurations. In these instances, it is possible for these lead “payload” aircraft to tow a platform specifically designed to provide power to the lead aircraft. Preliminary estimates identify that a Towed Platform can produce 4X more power than is needed to provide 24/7 flight for the towed platform. This qualifies as a net provider of electric power for propulsion of essentially unlimited upscale by attaching more and/or longer platforms.
When the sole and/or primary purpose of the Towed Platform is to provide power, it provides and ideal application of the design approach of distributing weight evenly—in a manner that lift is distributed evenly and toward the objective of equal and opposite lift and weight on a distributed basis. This eliminates stresses in structure and allows for especially efficient design methods.
A benchmark design of a distributed Towed Platform is use of thin structural batteries on which photovoltaic cells are mounted. Such a Towed Platform would provide uninterrupted 24/7 power to the lead aircraft.
c) Refueler Aircraft – Just as refueling aircraft transfer liquid energy in flight, so also, refueler aircraft can transfer electrical power. This can be via an umbilical cord or through energy beam transfer. For this application, there is a market and need for 24/7 aircraft that collect solar power and transfer that power as electricity or energy beams.
This approach is particularly effective because is separates the Towed Platform design from the payload design. This provides many and good solutions to the difficulty of takeoff and landing with towed platforms.
Designs that maximize flight efficiency and flight capabilities include distributed loads where lift is equal and opposite of weight on a local basis. In this design, platforms the sizes of football fields could be a half-inch thick. Unfortunately, during landing and takeoff, the lift does not counter the weight and structural problems emerge. The solution is to have dedicated 24/7 refueler aircraft that have assistance for takeoff and landing.
Novel designs are also possible to allow distributed aircraft to takeoff and land on a frequent basis. Those novel designs include VTOL capabilities.
d) Increase Efficiency – Old limitations simply do not apply in a aviation’s new era where efficiencies are 3X to 6X those of contemporary airliners. It is worth noting that even contemporary approaches based on battery storage can provide for hours of flight time, making electric power viable for essentially all application. Grid power could be used to charge the batteries if necessary.
At high L/D, gaining of altitude becomes more and more fraction of the entire energy need. It is worth noting that all altitude gained is also a source of energy for gliding. And so, high L/D does translate to increased efficiency is all aspect of flight (including takeoff/landing).
The Glide Ratio – An aircraft glides with a glide ratio where the horizontal distance traveled divided by the altitude change is approximately equal to the airframe’s L/D. Hence, and aircraft undergoing 20 miles of altitude change at a 100 L/D could travel 2,000 miles. This is more than enough to break through the shroud of darkness of night without using battery-powered propulsion; especially when traveling against Earth’s rotation.
Summary – The limitations of batteries to electric-powered flight simply do not apply to aviation’s new era with flight efficiencies 3X to 6X contemporary airliners.
Chapter 9. Batteries and Overcoming Limitations
Today’s electric vehicles are significantly limited by the weights and capacities of batteries. Those old limits do not apply to Towed Platform aircraft due to the following methods of overcoming these limitations: a) altitude energy storage, b) towed power platforms, c) refueler aircraft, and d) increase efficiency.
a) Altitude Energy Storage – HAPS/HALE aircraft fly at up 70,000 ft (or more) and are able to glide at night from 70,000 ft to 30,000 ft as a means to recover energy stored in altitude during the day. Both higher speeds and higher L/D enable even further maximum altitudes. This type of storage takes no additional weight and is very efficient in recovery.
The application is toward the effective use of aircraft operating 24/7 in transcontinental flight. The first leg of such trips is with Earth’s rotation and under direct solar power. The second half is against Earth’s rotation. Against Earth’s rotation, the first leg of the trip includes storing potential energy in altitude during evening daylight, while the second half uses stored energy and is at nights that might be shortened in duration by up to 50%. Here the vast majority of 24/7 operation can be achieved without battery-powered propulsion.
The Towed Platform aircraft are capable of higher speeds and higher L/D than the HAPS/HALE benchmarks. This translates to even higher altitude capabilities, which further expands applications.
An important sidenote is that most contemporary aircraft can achieve significantly improved efficiencies by using flat plate lift surfaces on upper and lower surfaces of aircraft. And so, this approach is not limited to “thin” Towed Platform airframes.
b) Towed Power Platforms – In some applications, the payload may not be susceptible to towed platform configurations. In these instances, it is possible for these lead “payload” aircraft to tow a platform specifically designed to provide power to the lead aircraft. Preliminary estimates identify that a Towed Platform can produce 4X more power than is needed to provide 24/7 flight for the towed platform. This qualifies as a net provider of electric power for propulsion of essentially unlimited upscale by attaching more and/or longer platforms.
When the sole and/or primary purpose of the Towed Platform is to provide power, it provides and ideal application of the design approach of distributing weight evenly—in a manner that lift is distributed evenly and toward the objective of equal and opposite lift and weight on a distributed basis. This eliminates stresses in structure and allows for especially efficient design methods.
A benchmark design of a distributed Towed Platform is use of thin structural batteries on which photovoltaic cells are mounted. Such a Towed Platform would provide uninterrupted 24/7 power to the lead aircraft.
c) Refueler Aircraft – Just as refueling aircraft transfer liquid energy in flight, so also, refueler aircraft can transfer electrical power. This can be via an umbilical cord or through energy beam transfer. For this application, there is a market and need for 24/7 aircraft that collect solar power and transfer that power as electricity or energy beams.
This approach is particularly effective because is separates the Towed Platform design from the payload design. This provides many and good solutions to the difficulty of takeoff and landing with towed platforms.
Designs that maximize flight efficiency and flight capabilities include distributed loads where lift is equal and opposite of weight on a local basis. In this design, platforms the sizes of football fields could be a half-inch thick. Unfortunately, during landing and takeoff, the lift does not counter the weight and structural problems emerge. The solution is to have dedicated 24/7 refueler aircraft that have assistance for takeoff and landing.
Novel designs are also possible to allow distributed aircraft to takeoff and land on a frequent basis. Those novel designs include VTOL capabilities.
d) Increase Efficiency – Old limitations simply do not apply in a aviation’s new era where efficiencies are 3X to 6X those of contemporary airliners. It is worth noting that even contemporary approaches based on battery storage can provide for hours of flight time, making electric power viable for essentially all application. Grid power could be used to charge the batteries if necessary.
At high L/D, gaining of altitude becomes more and more fraction of the entire energy need. It is worth noting that all altitude gained is also a source of energy for gliding. And so, high L/D does translate to increased efficiency is all aspect of flight (including takeoff/landing).
The Glide Ratio – An aircraft glides with a glide ratio where the horizontal distance traveled divided by the altitude change is approximately equal to the airframe’s L/D. Hence, and aircraft undergoing 20 miles of altitude change at a 100 L/D could travel 2,000 miles. This is more than enough to break through the shroud of darkness of night without using battery-powered propulsion; especially when traveling against Earth’s rotation.
Summary – The limitations of batteries to electric-powered flight simply do not apply to aviation’s new era with flight efficiencies 3X to 6X contemporary airliners.