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.

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 !

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

Here is the “ultimate” tuning for this 5000 usd aeroplane/motorglider.

Slight tuning on this “endless solar energy” using + direct solar take off capable craft.

Would this http://svsponline.co.uk/Mountain-High-Oxygen-Systems/ and this do it for a system http://www.ebay.com/itm/NEW-Portable-Mini-Air-Compressor-Electric-Tire-Infaltor-Pump-12-Volt-Car-12V-PSI-/400484008226 in a 45 kts tail wind the longest leg on Atlantic is doable in 6 hrs with Hippi at 7-8 km.

This might interest some. Solar Challenger had 23 m2 of solar panels that worked on 16.5% efficiency which weighed 30 kilos IRC. Today the efficiency is 22.8 % and small craft can have 3 kilos panels to beat the performance of SC ie the panels weigh 90% less. MC-30 Luciole holds one FAI record with 51 km electric flight.