Could solar powered passenger planes replace Zeppelin type air ships in the future ?

This should make all doubt disappear !

SOLAR EAGLE has 12 times less frontal area per passenger and 31% more power per person in cruise than on Solar Challenger !

Here is a “proof” that it has been sketched at least.

I was able to reduce frontal area 12% with strenuous 4 hour design session.

Interesting detail could be the fact that at 15-20 degrees declination of the sun and having only 60 people on board while 30 pedals energy the plane has 3 x more power ( to weight ratio ) still at cruise than Solar Impulse with same wing loading !

This means that plane can be flown late in the evening and early in the morning with just 1/3 of the capacity….or in very north during the winter !

Here is where it starts getting interesting.

When you take off with this plane only with a co-pilot and use max battery power in sun light you get better power to weight ratio than in Spitfire MkXIX on full boost and thus you can climb at 50 degrees angle…and if you decent away from the sun the sun can be really low too. I mean nowhere near the equator.

Below the other engine/prop efficiency at take off. This is a twin. :applause:

The best panels produce now 44.8 % max and best on aeroplanes than are thin and bent 22.8%. Their weight has gone down 50% since Paul MacCready times.

You are right about the size…therefore I squeezed it tighter…here is the most efficient and lightest concept’s specs that I was able to come up with.

Take off power on a sunny day 10 hp/person in a plane lighter than any glider ( and 1/3 of the drag per person of any glider ).

This much extra power actually makes the flight in cloudy day possible and as long as the batteries allow in a rain too….ie flying from 9 to five in countries where the sun rises pretty high at noon.

Where do you want the 180some people to sit while still maintaining such a small frontal area?

{snip}

Last bit, if you want to replace zeppelins, you are running some 60 years behind. Except for some novelty and promotional zeppelins and dirrigibles they have already gone the way of the dodo.

After we run outa oil there is only a change to fly electric or…either zeppelins or aeroplanes. Small frontal area happens always when you stack people behind each others.

with a 98 m span and large lifting body mid section.

In order to fit at existing airports the plane’s wingspan should be no more then 80 metres, unless you intend to add folding / pivoting wings which will increase the weight and maintenance costs dramatically.

but only 25 kg / m2 wing loading fully laden

For that to work you either need giant wings which, again, do not fit in the 80×80 metres box airports are designed for. An alternative is a flying wing, which existing airport infrastructure is ill-equiped to handle as well (gates, airbridges).

It has 3 hp per passenger power for cruise

I do not know if that will be enough or not, might be. However, to get the thing of the ground you will need more then that.

and 1/3 of the frontal area per person compared to small DuckHawk glider.

Where do you want the 180some people to sit while still maintaining such a small frontal area?

more efficient solar panels than on the wings

Solar panels are still too heavy to be practical in aviation. In the future they might be interesting to supplement other power sources, and who knows in the far future perhaps
they will be light enough for what you have in mind. But that won’t be anytime soon. Also, no solar panels have been approved for use in commercial aviation. Just on experimental kit.

Last bit, if you want to replace zeppelins, you are running some 60 years behind. Except for some novelty and promotional zeppelins and dirrigibles they have already gone the way of the dodo.

do you remember the ‘Solar Impulse” & its “Across America” flight, earlier this year ?

well, the average speed was then of ….. 28,8 kts 😀 ;
……………………………………………………………http://www.solarimpulse.com/timeline/view/7195#.UqsR8fCA1D8

friendly, Etienne

You apparently did not read what I wrote.

Solar Impulse flies at 7 kW power and weighs 1600 kilos. “I am flying” at 405 kW 30 000 ft higher ! Fact is that if you use straight surface on the lifting body ( or wing like Solar Challenger ) you can today use 44.8% efficient panels and at high you get 1360 W / m2 of sunlight ! My craft has 880 m2 of solar panel..½ of the 22.8% and an other ½ of the 44.8 % efficient kind.

So what this means that when you can have 3 times more power from panels compared to Paul MacCready times in 1981 you can make totally differend kinda aeroplanes and go much faster and much higher and travel several times longer distances. You can also go to 75 000 ft where you get as a free bonus 36% more power than at the sea level !

Study these facts carefully and you’ll see the light !

best regards,

Juke

PS: Just in case you math fails you 405 kw is 58 times more power than 7 kw !

SOLAR POWERED ??

do you remember the ‘Solar Impulse” & its “Across America” flight, earlier this year ?

well, the average speed was then of ….. 28,8 kts 😀 ;
……………………………………………………………http://www.solarimpulse.com/timeline/view/7195#.UqsR8fCA1D8

friendly, Etienne

I lay down some numbers to figure what I am after.

I have 180 seater ( 120 adults 60 kids => 80 kg and 40 kg ) craft with a 98 m span and large lifting body mid section.

Plane has nearly same power to weight ratio as Rutans Voyager; http://en.wikipedia.org/wiki/Rutan_Voyager but only 25 kg / m2 wing loading fully laden ( 1/5 th of the Voyager ). It has 3 hp per passenger power for cruise and 1/3 of the frontal area per person compared to small DuckHawk glider.

Duckhawks bigger sister Perlan “cruises” MACH 0.5 at 90 000 ft ( FL900 ). This does the same in FL750.

So less is more right ?

In the mid section I can use more efficient solar panels than on the wings ( 45 % vs. 23 % ) to get 400+ kW.

Wooden H-4 Hercules was already half weighed compared to newer less spanning crafts.

http://upload.wikimedia.org/wikipedia/commons/thumb/e/ee/Giant_Aircraft_Comparison.svg/800px-Giant_Aircraft_Comparison.svg.png