Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Airbus and Boeing are exploring the viability of electric planes

phys.org

Post reply on HN
Print view View original

41–50 of 149 posts

Re: Airbus and Boeing are exploring the viability of electric planes

#41

Post by objclxt »

pishpash wrote: post #37
cyberferret wrote: post #6

The stat that really woke me up to how popular travel was when an aviation magazine once posted that at any second of any day, there are at least one million people flying in an airplane somewhere. That's an entire good sized city full of people who are not in contact with the ground at any point in time you care to pick. And that article was quite a few years old, I wouldn't be surprised if that number has increased…

This doesn't sound right. Would like to see the numbers.

Seems pretty reasonable to me. There can be 9-10,000 flights in the sky at any one time (go check out any of the flight radar/tracking sites).

Re: Airbus and Boeing are exploring the viability of electric planes

#42

Post by kurthr »

lucb1e wrote: post #36
bpicolo wrote: post #21

Earlier quoted context omitted.

You can't scale up solar power to an aircraft carrying significant passengers / cargo.

Do you have anymore information on that, a link perhaps?

The weight for the mass of the passengers scales with the volume (m^3) while the area of the solar cells (and wing) to lift them scales with m^2. The typical solution for human scale aircraft is to fly faster (higher stall speed) and extend the length of the fuselage. Unfortunately, that combination doesn't increase efficiency so you end up needing even more fuel (or area and weight for batteries and PV).

The demonstrated PV aircraft are already pushing the lowest wieght, lowest drag wings with the highest efficiency PV and energy dense Batteries. This is a case where bigger is harder (not so with Zeppelins where structural material weight/stiffness scale to much larger sizes).

Re: Airbus and Boeing are exploring the viability of electric planes

#43

Post by dalore »

pjc50 wrote: post #33
cm2187 wrote: post #24

As a first step, they could make at least the take off and landing electric, that would help a lot with the noise and pollution around cities, i.e. where people live. I guess the batteries could be recharged during the flight for landing.

Takeoff is the hardest part requiring the most power, unfortunately.

But they are also close to the main grid so could charge up a big capacitor from the mains to get a boost.

Re: Airbus and Boeing are exploring the viability of electric planes

#44

Post by kolinko »

geff82 wrote: post #11
lancebeet wrote: post #7

Earlier quoted context omitted.

Who exactly are "we" and how should they be stopped? Flying around the world for two-day trips isn't something that the great majority of the human population will ever do.

Given the right technology, maybe we will!

Jetlag :( It's kind of sad that regardless of technology and money there is no way, and there might never be a way to just hop on from SF/Tokyo to Paris for a weekend and back, and enjoy it.

Re: Airbus and Boeing are exploring the viability of electric planes

#45

Post by usrusr »

pjc50 wrote: post #33
cm2187 wrote: post #24

As a first step, they could make at least the take off and landing electric, that would help a lot with the noise and pollution around cities, i.e. where people live. I guess the batteries could be recharged during the flight for landing.

Takeoff is the hardest part requiring the most power, unfortunately.

Takeoff, and landing abort. It might turn out to be economical to have hybrid engines that are fully optimized (in efficiency and in drag) for sustained climb load (or even just to cruise) that can only deliver takeoff/abort thrust using electrical assist. It could be enough to carry batteries for no more than a few minutes of assist!

I don't know though how much the efficiency of current jet engine drops off at the far ends of their throttle range.

Re: Airbus and Boeing are exploring the viability of electric planes

#46

Post by manquer »

kolinko wrote: post #44
geff82 wrote: post #11

Earlier quoted context omitted.

Given the right technology, maybe we will!

Jetlag :( It's kind of sad that regardless of technology and money there is no way, and there might never be a way to just hop on from SF/Tokyo to Paris for a weekend and back, and enjoy it.

What if your biological clock could be speed up or slowed down with a pill ?

Re: Airbus and Boeing are exploring the viability of electric planes

#47

Post by zeusk »

cm2187 wrote: post #24

As a first step, they could make at least the take off and landing electric, that would help a lot with the noise and pollution around cities, i.e. where people live. I guess the batteries could be recharged during the flight for landing.

Landings are mostly idle power until they lower landing gears in the last few miles; Take-off with fuel load is the most demanding leg and also the hardest to electrify.

Re: Airbus and Boeing are exploring the viability of electric planes

#49

Post by whitepoplar »

zeusk wrote: post #47
cm2187 wrote: post #24

As a first step, they could make at least the take off and landing electric, that would help a lot with the noise and pollution around cities, i.e. where people live. I guess the batteries could be recharged during the flight for landing.

Landings are mostly idle power until they lower landing gears in the last few miles; Take-off with fuel load is the most demanding leg and also the hardest to electrify.

...until they're not (e.g. failed landing, go-around)

Re: Airbus and Boeing are exploring the viability of electric planes

#50

Post by taf2 »

pjc50 wrote: post #35
jopsen wrote: post #15

From an engineering perspective how much harder would be to do a cross Atlantic high speed rail: Norway Canada ? Politically, it would probably be possible due to cost and risks.

The Channel Tunnel cost ~£200m per mile. The Atlantic is ~4000 miles across. That implies the Atlantic crossing would cost £800bn, slightly more than a trillion dollars and roughly the cost of the Iraq war and occupation.

Not sure the cost would be linear either since the Atlantic floor is probably deeper in certain sections
Post reply on HN