Comments on: SportStar EPOS Electric Airplane Makes Its First Flight

By: 김지현

김지현 — Fri, 24 May 2013 01:08:00 +0000

Thank you for the good article.

Let me give you one comment.
Actually, not DK but Kokam Co., Ltd, Korea supplied lithium polymer battery for the project.

Hope you correct it in your article.

If you have any questions, feel free to contact me.
Victoria Kim
Marketing, Kokam Co., LTd.
victoria@kokam.com

By: arne-nl

arne-nl — Wed, 17 Apr 2013 20:25:00 +0000

Why in the world would it need to compress air? Wouldn’t just an electric motor to turn the propellor be sufficient? Or is that too simple?

By: agelbert

agelbert — Tue, 16 Apr 2013 18:29:00 +0000

You may be thinking of the simplest type of jet which is called a ram jet. Those were the early types. The gas turbine (turbofan) jet engine is what runs jets AND turbobtops (turboprops drive an internal fan on a shaft that turns the outside propeller instead of a bunch of jet exhaust funneled powerfully out the rear – it goes out the rear in turboprops too but minus the power thrust) now. An electric would have all the compressor stages WITHOUT burner cans so it would have to compress the air to a greater amount since no combustion would occur.
Granted, it doesn’t seem practical to me. The squiggly looking props NASA has designed for propeller driven aircraft run from a straight electric powered by PV + BATTERY POWER SEEMS MORE LOGICAL AND PRACTICAL.

By: Kompulsa

Kompulsa — Tue, 16 Apr 2013 13:42:00 +0000

My apologies. It is a turboprop plane, so it should not have been called a jet.

The article will be corrected.

Jets use jet propulsion to produce thrust, whether they are combustion engines or not (they don’t have to be).

By: arne-nl

arne-nl — Tue, 16 Apr 2013 09:50:00 +0000

Remember the portable telephones from the 80’s? I bet your current cell phone doesn’t look anything like that

Battery technology is constantly improving and judging from the research now being done, energy density is expected to increase by at least a factor of 3 in the coming 10-20 years. So, in that timeframe this aeroplane could develop into something that has an operating time of 3 hours and a range of 450 km. I remember people proclaiming with the same 100% certainty that electric cars would ‘never’ become viable. So your prophetising ‘never’ seems to ignore reality .

This aeroplane already represents a compelling proposition for certain niche markets. What I have in mind is eco friendly sightseeing flights over nature reserves that are off limits for normal aircraft due to noise considerations. Eco tourism is growing fast and people will very much seek to enjoy the aerial view of nature without (in a sense) destroying it. These flights are usually short and if you make the battery swappable, charge time is not an issue. It would need a few more seats though. On top of that you have the advantages in operating cost that Ronald mentioned.

Markets are conquered in phases. You start out with something that only serves a niche and each iteration of the technology will attract an exponentially larger share of customers. No breakthroughs needed. Cell phones have conquered the world in exactly the same way and without any miracle breakthrough along the way. Just a continuous stream of incremental improvement sufficed to accomplish that.

Simple physics puts the theoretical energy density of a lithium air battery at 12 kWh/kg, about the same as hydrocarbon fuels. But the irony here is that you are claiming to have ‘simple physics’ on your side.

By: arne-nl

arne-nl — Tue, 16 Apr 2013 06:44:00 +0000

How can it be a turboprop if it is electric?

By: anderlan

anderlan — Mon, 15 Apr 2013 13:50:00 +0000

So, nearly a gallon’s worth of energy for an hour of flying. That is awesome. A little more than however Miles you can get…PGe. So, 90MPGe, maybe. Just like a tiny petrol airplane gets about the same as a gas SUV, a tiny electric airplane gets about the same as an E-SUV!

By: Pete Stiles

Pete Stiles — Mon, 15 Apr 2013 11:13:00 +0000

If this were a turbo jet then what would be fed to the turbine; Electrons? I think that would make it an Ion drive !! This article is dumb !

By: Ronald Brakels

Ronald Brakels — Mon, 15 Apr 2013 05:36:00 +0000

Well, a light plane might cruise at about 60% of maximum engine capacity, so that would suggest about a 30 kilowatt-hours of charge in the batteries since it can fly for an hour, giving about 5 kilometers per kilowatt-hour.

By: Thierry Phillips

Thierry Phillips — Mon, 15 Apr 2013 03:40:00 +0000

Exactly.

By: anderlan

anderlan — Mon, 15 Apr 2013 03:39:00 +0000

How many kWh in the batteries? This plus range, and we could calculate MPGe. I bet it would beat most gas GROUND CARS!

By: Ronald Brakels

Ronald Brakels — Mon, 15 Apr 2013 02:39:00 +0000

Internal combustion engine planes need a maintenance check every 50 hours or 6 months which costs about $800 and may need an engine replacement every 2,000 hours. And they can burn $50 worth of fuel an hour. Electric planes eliminate most of these costs. So there are advantages to electric flight and simple economics suggests it could have useful applications in agriculture where the current high cost running light aircraft limits their use. And no, I don’t know why it’s called a jet.

By: TruthTeller.

TruthTeller. — Sun, 14 Apr 2013 22:22:00 +0000

Stupid, poorly written and poorly researched non-article. This isn’t a jet, genius. And this is an incredibly stupid line of research – simple physics indicates that electric aircraft will not be viable for anything except experiments until a new power source or extremely dense power source is developed. I suggest a new line of business for the author.

By: agelbert

agelbert — Sun, 14 Apr 2013 20:41:00 +0000

It could be a turboprop (a jet turbine with a large outside propeller). At slow airspeeds (less than 250 mph) and lower altitudes (below 10,000 ft) a turboprop is more efficient. An electric turbine would, of course, not use burner cans with jet fuel at a certain compression stage but would have the multivaned air compression stages just the same. One advantage of these motors may be the alloys used in the vanes don’t have to handle as high temperatures as a gas turbine so, in theory, they would be cheaper to make.

By: jburt56

jburt56 — Sun, 14 Apr 2013 20:18:00 +0000

Fuel cells.

By: Rhodomel Meads

Rhodomel Meads — Sun, 14 Apr 2013 17:01:00 +0000

“According to Tech Vehi, the SportsStar EPOS, which is just an electric jet, made its first flight a few days ago.”

Does a jet plane have a propeller like the photo shown? This is bigger news to me, as it will redefine the meaning of jet propulsion using propellers.