Electrically Powered Ultralight Aircraft

"James Sleeman" wrote in message
ups.com...
On Aug 6, 4:52 am, Larry Dighera wrote:
Electrically Powered Ultralight Aircraft

It's a nice idea, but realisitically there are too many problems, not
the least of which is battery size, weight, cost and safety. I don't
really see batteries as a viable in the near future (I struggle to see
them as viable in the distant future either).


It depends on the demand. During the worldwide battlebots craze a few years
ago there were marked technological improvements in battery technology in
the course of about four years. I imagine hybrid vehicles are really going
to push the state of the tech. It might not be viable yet, but if there's
sufficient motivation and investment it could really happen.

That would rock. Even if the cost is the same, the reduction in sound would
be wonderful. You'd want a reserve battery for the purpose of getting you
home when your mains began to taper off, though.

-c

Gattman wrote:
"James Sleeman" wrote in message
ups.com...
On Aug 6, 4:52 am, Larry Dighera wrote:
Electrically Powered Ultralight Aircraft

It's a nice idea, but realisitically there are too many problems, not
the least of which is battery size, weight, cost and safety. I don't
really see batteries as a viable in the near future (I struggle to
see them as viable in the distant future either).


It depends on the demand. During the worldwide battlebots craze a
few years ago there were marked technological improvements in battery
technology in the course of about four years. I imagine hybrid
vehicles are really going to push the state of the tech. It might
not be viable yet, but if there's sufficient motivation and
investment it could really happen.


Come on, it's not like there isn't sufficient motivation out there now and
it isn't coming from battlebots. If anyone comes up with a battery that can
power and automobile for 4 hours at highway speeds and is affordable to
produce they will be very wealthy.

If they can make one that is as efficient as a tank of gasoline they will
shortly become very, very wealthy.

"Gig 601XL Builder" wrDOTgiaconaATsuddenlink.net wrote in message
...

Come on, it's not like there isn't sufficient motivation out there now and
it isn't coming from battlebots. If anyone comes up with a battery that
can power and automobile for 4 hours at highway speeds and is affordable
to produce they will be very wealthy.

If they can make one that is as efficient as a tank of gasoline they will
shortly become very, very wealthy.

I agree. It's on the way. Wasn't too long ago that terms like "lithium
ion" and "nickle metal hydride" were unheard of to the common consumer.

Five or six years ago your choices were Hawker Genesis-style Sealed Lead
Acid or custom-built NiCad battery arrays which is what we used. NiMH and
lithium ion weren't available or affordable but the proliferation of power
chairs, stuff like the Segway, electric scooters and so forth have really
pushed the demand for lightweigh, high performance batteries.

-c

Gattman wrote:
"Gig 601XL Builder" wrDOTgiaconaATsuddenlink.net wrote in message
...

Come on, it's not like there isn't sufficient motivation out there
now and it isn't coming from battlebots. If anyone comes up with a
battery that can power and automobile for 4 hours at highway speeds
and is affordable to produce they will be very wealthy.

If they can make one that is as efficient as a tank of gasoline they
will shortly become very, very wealthy.

I agree. It's on the way. Wasn't too long ago that terms like
"lithium ion" and "nickle metal hydride" were unheard of to the
common consumer.
Five or six years ago your choices were Hawker Genesis-style Sealed
Lead Acid or custom-built NiCad battery arrays which is what we used.
NiMH and lithium ion weren't available or affordable but the
proliferation of power chairs, stuff like the Segway, electric
scooters and so forth have really pushed the demand for lightweigh,
high performance batteries.
-c

Do me a favor Gattman. What is the weight of the most effeicent battery that
could power an automobile at highway speed and how long will it do so and
how long to recharge?

"Gig 601XL Builder" wrDOTgiaconaATsuddenlink.net wrote in message
...

Do me a favor Gattman. What is the weight of the most effeicent battery
that could power an automobile at highway speed and how long will it do so
and how long to recharge?

Well, if I tried to answer that I'd sound like mx. I don't know what the
"most efficient" battery is for that purpose. It's a hell of a lot heavier
than the 250-250 pound machines I worked with. I think 4-6 SLAs--possibly
the least efficient--would pull a vehicle, but I doubt it would make highway
speed and if if it did it wouldn't be for more than a few minutes. Charge
time for each battery would probably be a couple of hours, maybe longer.

I bet it would weigh a hell of a lot more than a Rotax. Internal combustion
is still the most bang for the buck this side of nuclear.

I think the most realistic use of an electric motor in an aircraft would be
in the context of something like a glider, for maintaining altitude or
finding a thermal or just getting home. It would be fun to fly an
ultralight around the pattern under electrical power, but I wouldn't stray
very far.

-c

Gattman wrote:
"Gig 601XL Builder" wrDOTgiaconaATsuddenlink.net wrote in message
...

Do me a favor Gattman. What is the weight of the most effeicent
battery that could power an automobile at highway speed and how long
will it do so and how long to recharge?

Well, if I tried to answer that I'd sound like mx. I don't know
what the "most efficient" battery is for that purpose. It's a hell
of a lot heavier than the 250-250 pound machines I worked with. I
think 4-6 SLAs--possibly the least efficient--would pull a vehicle,
but I doubt it would make highway speed and if if it did it wouldn't
be for more than a few minutes. Charge time for each battery would
probably be a couple of hours, maybe longer.
I bet it would weigh a hell of a lot more than a Rotax. Internal
combustion is still the most bang for the buck this side of nuclear.

I think the most realistic use of an electric motor in an aircraft
would be in the context of something like a glider, for maintaining
altitude or finding a thermal or just getting home. It would be fun
to fly an ultralight around the pattern under electrical power, but I
wouldn't stray very far.

-c


I understand and thank you for not MXing us. But the point isn't the weight
of the battery as compaired to a Rotax or any other engine. The issue I had
been getting at is the weight of the battery in comparison to the weight of
full load of gasoline.

Let's take my 601XL. 2 aluminum 12 gallon tanks each tank ways let's say 10
pounds add in 145 lbs of fuel and you have 165 pounds of transportable
energy that will produce ~100HP for about 4 hours.

My question to anyone is what is the lightest battery that is capable of
powering any motor that will produce the equivilent power for and equal
amount of time?

check out the article on regenerative soaring at www.esoaring.com I
think I may have heard that Taras Kiceniuk will be giving a talk on
this subject at Tehachapi this Labor Day. He's been working on this
idea for a while...
Bill

In rec.aviation.piloting Gig 601XL Builder wrDOTgiaconaATsuddenlink.net wrote:
Gattman wrote:
"Gig 601XL Builder" wrDOTgiaconaATsuddenlink.net wrote in message
...

Do me a favor Gattman. What is the weight of the most effeicent
battery that could power an automobile at highway speed and how long
will it do so and how long to recharge?

Well, if I tried to answer that I'd sound like mx. I don't know
what the "most efficient" battery is for that purpose. It's a hell
of a lot heavier than the 250-250 pound machines I worked with. I
think 4-6 SLAs--possibly the least efficient--would pull a vehicle,
but I doubt it would make highway speed and if if it did it wouldn't
be for more than a few minutes. Charge time for each battery would
probably be a couple of hours, maybe longer.
I bet it would weigh a hell of a lot more than a Rotax. Internal
combustion is still the most bang for the buck this side of nuclear.

I think the most realistic use of an electric motor in an aircraft
would be in the context of something like a glider, for maintaining
altitude or finding a thermal or just getting home. It would be fun
to fly an ultralight around the pattern under electrical power, but I
wouldn't stray very far.

-c


I understand and thank you for not MXing us. But the point isn't the weight
of the battery as compaired to a Rotax or any other engine. The issue I had
been getting at is the weight of the battery in comparison to the weight of
full load of gasoline.

Let's take my 601XL. 2 aluminum 12 gallon tanks each tank ways let's say 10
pounds add in 145 lbs of fuel and you have 165 pounds of transportable
energy that will produce ~100HP for about 4 hours.

My question to anyone is what is the lightest battery that is capable of
powering any motor that will produce the equivilent power for and equal
amount of time?

If you go to http://xtronics.com/reference/energy_density.htm you find
the energy densities of a lot of things.


Propane (liquid) 13,900 Wh/kg
Diesel 13,762 Wh/kg
gasoline 12,200 Wh/kg
Ethanol 7,850 Wh/kg
Methanol 6,400 Wh/kg
Secondary Lithium - ion Polymer 130 - 1200 Wh/kg
Primary Zinc-Air 300 Wh/kg
Lead Acid Battery 25 Wh/kg

So batteries have to improve by a factor of 10 to match gasoline.




--
Jim Pennino

Remove .spam.sux to reply.

"Gig 601XL Builder" wrDOTgiaconaATsuddenlink.net wrote in message
...

Let's take my 601XL. 2 aluminum 12 gallon tanks each tank ways let's say
10 pounds add in 145 lbs of fuel and you have 165 pounds of transportable
energy that will produce ~100HP for about 4 hours.

My question to anyone is what is the lightest battery that is capable of
powering any motor that will produce the equivilent power for and equal
amount of time?

Well, depending on which end of the gearbox it's measured, 40+ pounds of
NiCAD batteries got between 1-4 HP at maybe 70% motor power for 20 minutes
max before the battery output began to taper off. For perspective, the
Etek motor used on the ultralight in the link is probably about twice as
powerful as the motors we were using, so maybe for a ballpark measurement I
could double the battery time for the same weight. Theoretically if you
managed and cooled your batteries correctly you could get ~30 minutes for
that 40 pounds of batteries, or maybe two hours if you quadrupled it for
your ~160 pounds. Max.

Too much weight for an ultralight, and no way it's gonna get near 100HP.
Again, that's just a ballpark estimate.

-c

Gattman wrote:

I agree. It's on the way. Wasn't too long ago that terms like "lithium
ion" and "nickle metal hydride" were unheard of to the common consumer.


It takes a lot of energy to manufacture those batteries ... and recycle
them when they are used up. You have to factor that into the equation.

These batteries have high energy per unit volume but they cost a lot
of money because it takes a lot of energy to produce them.