Towards the most efficient freight vehicle.

[Kohai_Khaos]

Solar panels are indeed heavy (and expensive, those 46% panels I quoted haven't gotten out of being experimental things yet, because so very expensive to make), in the 10 kg/m² range for ones put on houses, but how about I be nice, and give you the ~77 W/kg that we get in the ones we send to space. That's about 6 kg/m², assuming the ones going to space even had the efficiency we're talking about here, which has only been demonstrated in the lab. On the Aeroscraft, that's 64.008 * 35.9664 * 6 = 13,812.8239872 kg of solar panels for the power numbers I had up earlier, if it was a large rectangle in the sky. This is that 1 MW of power generation at some of the higher loads you can expect.

You're going to want a fuel cell to store 1/3 of the 1,058,983.172352 * 16 = 16,943,730.757632 Wh you'll be producing with 16 hours of daylight so that you can keep the same speeds and such during the 8 hours of night (unless you intend to not be useful at nighttime). So we're storing 5,647,910.252544 Wh at minimum. That's 20,332,476.909158 kJ, and the enthalpy of formation for water is -285.8 kJ/mol, which is all I need because H₂ and O₂ have enthalpies of formation of 0. The mass of H₂, which is needed on a 1 mol:1 mol ratio with the water produced, is 2.01588 kg/mol

Time for some crazy math: 20,332,476.909158 kJ / -285.8 kJ/mol * 2.01588 kg/mol = 142,284.652968 kg of hydrogen need to be kept in some kind of storage to do this. If you were crazy enough to put it in the balloon, it would need to stretch an extra 116,150.737117 m³ as the day went on to remain neutrally buoyant at sea level. Which will be entertaining for a balloon that's only 64.008 * 35.9664 * 17.0688 m in size (39,294.7217 m³, yes, the hydrogen would triple the size of the airbag, I doubt that the aircraft would work if you did this, at least not realistically).

Additionally, even if you did store the hydrogen in the balloon (and therefore avoid having to deal with it literally weighing you down and taking up a chunk of payload), you still have to deal with the water when you make it. If you plan to attempt to electrolyze it back during the day, that'll be 1,281,648.93146 kg of water you need to store in the interim. This is why you don't do the electrolysis in an aircraft: the water is stupidly heavy.

I'm not even accounting for the mass of whatever tankage is holding this, or anything else. This is just your fuel.

Unless you intend to be grounded at night, you cannot expect to do this so easily.

To contrast, a Boeing 747, because might as well stick with one plane today, generally carries 144,870.2 kg of fuel. Oh, sure, it's 4 engines weigh up at 15,620 kg, somewhat more than all of the solar panels...but those engines also produce anywhere from 60 to 200 times as much power, depending on velocity. The mass of the solar panels is directly related to the amount of power they produce, so it's not exactly like there's some cutoff point where the panels start outstripping these combustion engines on a pound-for-pound bases, except maybe for really, really small things.

You do not save any real amount of fuel weight, and unless you are dumping the water (and therefore no longer need solar panels anyway), you actually end up weighing a lot more than a Boeing. If you dump the water, however, you lose your ability to just stay in the air with no need for anything like refueling, and you're back to "Might as well use jet fuel or diesel again because it would give us more horsepower anyway and the infrastructure for its supply is already there".

Let me put it this way: Filling up the Boeing with a full load of fuel costs $77,996.45. This is enough fuel to fly 9,800 km (its maximum range), and the jet's maximum speed is 955 km/h. Do a little math, the minimum amount of time that the plane can stay in the air with that fuel is ~10.26 hours.

Filling up your lovely little airship with enough hydrogen to run for 8 hours at about 333.3 kW is gonna be costly, especially right now, with the supply as low as it is. There's no real current price set on hydrogen (not much of a market, after all), however, the Worldwide Aero Corporation is not an energy company or in the business of making hydrogen. This leaves them to likely be purchasing their hydrogen from someone else, at prices ranging from $2.20/kg to $3.08/kg: $313,026.24 to $438,236.73. If produced on-site, for about $0.70/kg, $99,599.26. For not even enough fuel to last as long in the air as the Boeing, while running with somewhere along the lines of 180 to 300 times less power. Its range is also, I might add, significantly less than the Boeing's, which means it isn't even getting farther out than the Boeing for that money. It's slower than the Boeing, with even the quoted 120 knots (which is for the engines with a lot more horsepower than what you're offering in the solar situation), so much so that in the time it takes for the Aeroscraft to get somewhere, the 747 can fly there, fly back, fly there again, and already be home again when the Aeroscraft finally gets to the destination (Boeing cruising speed is a respectable 481 knots).

So the per-mile cost of fuel is higher for the Aeroscraft, while it's still so slow that a plane can fly back and forth enough times that any difference in payload is back in the plane's favor.

So tell me, should we go with the full fuel cell cycle, trying to recycle hydrogen into water and back again? Or should we just pump in hydrogen? Because neither one is economical. That's kinda why the people running the company aren't pushing for a hydrogen-powered Aeroscraft, but one powered by traditional fuel.

There is something wrong with your numbers, I will answer you later.

"There's something wrong with your math, but I won't bother checking right now. Pushing you off works fine to get you to go away."

[AngelLestat]

Sorry for the delay, bussy day, also I wanna search for accurate drag coefficients and also wanna find lift coefficients to calculate the max altitude with hydrogen instead hellium. But I could not find it.

The drag equation for airships:

D= 1/2*air density * u sqr * V exp (2/3) * Cd

Air density at 6000m: 0.6

Cd=0.04 (old zeppelings reach 0.025) but this has some ailerons and body lift.

Speed: 50m/s Cruise speed

The volume already calculated in m3 here

Drag Values and power requirements.

Model ----- Drag ----- Power

Pelican--> 21240N --> 1Mw (the prototype has lower altitude and power, the real engines added has 0.85 Mw)

66t --> 89400N --> 4.5 Mw

250t --> 206820N --> 10 Mw

500t --> 296100N --> 14 Mw

8000t --> 1091340--> 54Mw (576m long version)

64000t --> 89855320N --> 90 Mw (1000m long version)

Sorry Kohai_Khaos, your math was good, the only bad was the four 747 engine assumption which give you 191 Mw.

Pv efficiency at 6000m rise a 27% due cold and less solar light block it by the atmosphere.

It does not weight as much you said.. is a lot less, I will look it tomorrow, but the choice efficiency needs to be 20% because is cheap.

Hydrogen has 3 times more energy density by Kg than any other fuel. So when we rise altitude, instead vent or carry extra hydrogen, we consume it as energy , for the 250t version we can consume from the same envelope... i dont remember.. I will do the math tomorrow. It was something like 15 Tons.

We need to carry extra tanks of hydrogen, but not much. Instead it does not reach to cover all the power needed.

But I have another trick of how to make it 100% energy independent without decrease speed or remove payload.

I will complete this study tomorrow, also I dint read all your last post, it will be later. cya (thanks Iskierka a Kohai, those post really help)

Edit: Now I see where I wrong in my first PV calculation. It was due this video:

https://youtu.be/ndMapWaxgfA?t=1m48s

It said ML866 which in the table corresponds to the 66t version.

http://aeroscraft.com/communities/4/004/011/780/344//images/4607832198.jpg

So I knew that the prototype had 3 engines of 274kw, but then I scale them as if their were from the 66T version to the 250t version. But those engines are from the pelican.

Edited April 9, 2015 by AngelLestat

[Kohai_Khaos]

Okay, I figured out why some of my numbers felt really off, especially when looking at places giving numbers for the energy density of hydrogen; all the stupid sources in the world can't bother to label as g/mol when I ask for molar masses. I want standard units, and that means a kg. 0.00201588 kg/mol, so my energy density math in regards to how much hydrogen you need is off by 1000. I'll admit that much.

[EdFred]

I am still waiting your corrections about the airships claims you quote me.

What? That airships just like every other aircraft are subject to the same hindrance or help from head/tailwinds? If you have an airship that travels at 100kts (which is over twice as fast as what the Goodyear Blimp is currently capable of) that is the airspeed. Not the ground speed. But let's say you have an airship capable of 100kt airspeed. It doesn't matter if that blimp is 2m long or 2km long, when you fly into a 30kt headwind your ground speed - will be reduced by 30kts. Again, it doesn't matter if the airship is 2m, 20m, 200m, or 2000m long. The groundspeed is reduced by 30kts. Same goes for an A380, a 747, or a Cessna 172. Building it bigger doesn't matter. It's still reduced by 30kts - down to 70kts ground speed.

You also made the statement that you can reduce transit times by 50% when heading downwind while only increasing them 25% when flying the opposite direction. Well, lets do the math on that. Lets take our same 100kt airship, and with 0 wind it will take 5 hours to travel that 500nm. At what (ground)speed will it have to travel to do it in 2.5 hours? 200kts, right? 100kts airspeed + 100kt headwind. So the only way that is happening is with a 100kt tailwind. But what happens when we try flying into that 100kt headwind with a 100kt (airspeed) airship. 100kts airspeed - 100kts headwind = 0 knots of ground speed. The absolute best you can do in that situation is to maintain your current position. Your airship isn't going anywhere.

Making an airship (or airplane, or any aircraft) bigger or longer does not make it less subject to the forces of headwinds or tailwinds. This is why you are in error.

[AngelLestat]

Okay, I figured out why some of my numbers felt really off, especially when looking at places giving numbers for the energy density of hydrogen; all the stupid sources in the world can't bother to label as g/mol when I ask for molar masses. I want standard units, and that means a kg. 0.00201588 kg/mol, so my energy density math in regards to how much hydrogen you need is off by 1000. I'll admit that much.

Well you were right in one thing. It does not have much sense to have PV, Just H2 with fuel cell increase the efficiency of the airship by a lot.

But it does not mean that airships are not good for PV, just this design is not good for PV.

However aeroscraft with PV may be very good for some kind of applications, as hospital or any application where is not need to travel very fast, or when is not in constant movement or with low distant travels, also as backup source in case something happen with the fuel cell.

I already know how to change this design:

https://youtu.be/6alsthqayLo?t=4m4s

keeping the aerodynamic lift, freight and other good aeroscraft virtues.

I dint show my second trick, I could get extra 25 or 30% extra energy from an indepent renewable source in the air, but my objective was 100%, so I need to change the design first.

With that design, you can have a 40% efficiency solar panel because the area is so small that it worth it, also the waste heat can be used too.

Note for the same range energy that you need, using the same hydrogen from the envelope may be almost enoght.

In that way you save several tons of fuel which you can add to the payload or range.

Huge airships does not have any problem with range or weight. They can have anything they want.

Fuel cell efficiency with hydrogen 60% and thermal engine efficiency with gasoil 35%, is one or the other.. I just add that to compare and calculate the extra payload .

To calculate the power received I use 400w average by day, because you dont have clouds almost never, you get extra efficiency by cold and altitude, then multiply per 0.2 Solar cell efficiency.

PV info and data choice:

cubesats PV:

0.86kg/m2 30% efficiency.

http://laser-connect.weebly.com/uploads/4/9/2/3/4923848/talk_8_s_irvine_glyndwr_uni.pdf

House roof PV:

1.7kg/m2 15% efficiency

http://miasole.com/uploads/media/Miasole_Solar_Metal_Roof_Brochure_V01.pdf

I found those, just imagine one in the middle.

1kg/m2 20% efficiency does not sound crazy because it does not need the cover.. Just the cell, then this is

interleaved between 2 substrate materials as aluminum, titaniaum or some carbon base, which form the same envelope

and the cell helps to provide strenght to the envelope.

Also avoding any flamable result in the final compound envelope.

This same thing is used in this design:

http://solarflight.blogspot.com.ar/

A cute video on solar freight airships:

Rusia is also starting to design airships with hydrogen mix in mind:

http://www.vanhorne.info/files/vanhorne/bouyancy-control-augur-lr.pdf

What? That airships just like every other aircraft are subject to the same hindrance or help from head/tailwinds? If you have an airship that travels at 100kts (which is over twice as fast as what the Goodyear Blimp is currently capable of) that is the airspeed. Not the ground speed. But let's say you have an airship capable of 100kt airspeed. It doesn't matter if that blimp is 2m long or 2km long, when you fly into a 30kt headwind your ground speed - will be reduced by 30kts. Again, it doesn't matter if the airship is 2m, 20m, 200m, or 2000m long. The groundspeed is reduced by 30kts. Same goes for an A380, a 747, or a Cessna 172. Building it bigger doesn't matter. It's still reduced by 30kts - down to 70kts ground speed.

You also made the statement that you can reduce transit times by 50% when heading downwind while only increasing them 25% when flying the opposite direction. Well, lets do the math on that. Lets take our same 100kt airship, and with 0 wind it will take 5 hours to travel that 500nm. At what (ground)speed will it have to travel to do it in 2.5 hours? 200kts, right? 100kts airspeed + 100kt headwind. So the only way that is happening is with a 100kt tailwind. But what happens when we try flying into that 100kt headwind with a 100kt (airspeed) airship. 100kts airspeed - 100kts headwind = 0 knots of ground speed. The absolute best you can do in that situation is to maintain your current position. Your airship isn't going anywhere.

Making an airship (or airplane, or any aircraft) bigger or longer does not make it less subject to the forces of headwinds or tailwinds. This is why you are in error.

The goodyear blimp is very small, all small airships had low speed.

But I never said what you claim I said. I just said that airships at big scale can be faster or fly heigher, etc.

Is not due drag, is due that they can carry more powerfull engines and the extra fuel to feed those engines..

Source: http://enu.kz/repository/2010/AIAA-2010-1395.pdf (I dont like that design because its half airplane and half airship) but you can see how the speed increase with the size.

Also about the 25% delay chance against the 50% faster change.. that is true, and the values are almost pesimist.

How people with hot air ballons achieve to travel most of the times where they want to?

In fact, the first time that someone circumnavigated the globe without refuel was with a ballon. You just need to choice your wind layers that most fit you, you have doppler radars onboard + all the weather info from the world.

Just check here:

http://earth.nullschool.net/

And imagine 1 place with 1 destiny, then try to find the best route searching winds at different altitude. (is in pressure, 250, 700, etc.)

[EdFred]

Did you even understand what I said or did you just ignore it?

[AngelLestat]

The first part of your paragraph is totally explained. (still I dint see any word of your part)

The second is also totally explained but it seems that you might still have some doubts.

Your example is traveling only 500 nm where in fact the range is +5000 nm, but even in that example there is not much problem. you lose the chance to dodge them going port or starboard, but you can still choice altitude.

For short trips it means mostly that you travel over land, winds are not strong over land, you have a chance of 1 in 15 (world average) to find winds higher than 30 knots, then you have 1 in 3 chances to find headwinds (120 degress cone in front of you), and in those weird cases you have only 1 in 3 chances to not be able to dodge them with altitude change, then 1 in 135.

For long trips you always find a good path or at least the less bad. So yeah, half of the times delays of 25% and the other half 50% of time decrease (average)

And the only way you understand this is studying wings with the app that I gave to you.

You use hard words when you disagree in 3 points that I made, I was right in the 3 but is sure that you will not retract. Fine.. live with that.

Edited April 10, 2015 by AngelLestat

[EdFred]

The first part of your paragraph is totally explained. (still I dint see any word of your part)

The second is also totally explained but it seems that you might still have some doubts.

Your example is traveling only 500 nm where in fact the range is +5000 nm, but even in that example there is not much problem. you lose the chance to dodge them going port or starboard, but you can still choice altitude.

For short trips it means mostly that you travel over land, winds are not strong over land, you have a chance of 1 in 15 (world average) to find winds higher than 30 knots, then you have 1 in 3 chances to find headwinds (120 degress cone in front of you), and in those weird cases you have only 1 in 3 chances to not be able to dodge them with altitude change, then 1 in 135.

For long trips you always find a good path or at least the less bad. So yeah, half of the times delays of 25% and the other half 50% of time decrease (average)

And the only way you understand this is studying wings with the app that I gave to you.

You use hard words when you disagree in 3 points that I made, I was right in the 3 but is sure that you will not retract. Fine.. live with that.

So. Much. Wrong. I can't even begin to start. You either have no clue what you are talking about, or you are just being obstinate. Either way I am wasting my time.

[Red Iron Crown]

This is meant for all participants: Please refrain from making personal attacks. Discuss the merits of the idea or lack thereof, but stay away from the character of the poster.

It is both rude and a logical fallacy.

[AngelLestat]

Topic Update:

The first steps of some of the things that I defend and predict in this topic are being taken.

1- "trigger 2 days ago" The United States’ Patent and Trademark Office (USPTO) has granted U.S. patent number 9,016,622 for the cargo airship’s ‘Flight System for a Constant Volume Variable Buoyancy Air Vehicle,’ with Onboard ‘Control-of-Static-Heaviness’ (COSH) Management.

The receipt of this patent marks a game-changing advancement in the field of aviation.

http://www.intelligent-aerospace.com/articles/2015/05/aeros-patents-cargo-airship-technology.html

2- "1 day ago" A new Congressional bi-partisan Cargo Airship Caucus was established in the House of Representatives yesterday, Co-Chaired by Rep. Tom Rooney (R-FL) and Rep. Brad Sherman (D-CA). The Congressional Caucus will work to hasten the takeoff of the cargo airship industry in the U.S., an infrastructure independent mode of transportation, in support of military, economic, national security, diplomatic and environmental objectives. Both Co-Chairmen explained their motivations for leading this initiative when announcing the caucus yesterday, stating:

“Modern cargo airships have nearly three times the fuel efficiency as air transport alternatives, and can land in very remote locations,†said Congressman Brad Sherman. “They have enormous potential to enable economic development opportunities and accelerate export logistics, expand U.S. capabilities in disaster relief response, and drive greenhouse gas reductions in aviation.â€Â

“The recent advances in airship technology are exciting, and the Caucus will help illustrate the breadth of benefits enabled by cargo airships’ efficient and infrastructure independent operations, including benefits to military operational tempo and mission flexibility, enhanced delivery capability, and operational cost savings,†said Congressman Tom Rooney.

Members of the Cargo Airship Caucus will collaborate to accelerate deployment of modern airships capable of efficiently delivering hundreds of tons of large equipment, vehicles, containers, or other cargo virtually anywhere. For the military, this new generation of airships has the potential to revolutionize the future of intra-theater airlift, greatly increasing heavy cargo lift capability, reducing the logistics footprint in theater, reducing dependence on foreign airbases and ports, reducing the effectiveness of anti-access strategies employed by adversaries, and radically changing the hub and spoke logistics structure to one of point-to-point delivery. The cargo airship’s introduction to global logistics is expected to reduce operational constraints on future heavy-lift, radically reduce energy use for aircraft operations on a ton/mile basis, permit high-payload operations directly into austere locations with little infrastructure, increase delivery speed for cargo shipped by boat, and reduce the need for intermodal transport to move cargo from origin to point-of-need, with corresponding reductions in delivery time.

More in the link...

http://www.prweb.com/releases/2015/03/prweb12575714.htm

3- FAA's Relaxed Drone Rules, FAA chief Michael Huerta signaled the agency’s openness to approving beyond visual line of sight (BVLOS) operations and announced a couple of research projects aimed at demonstrating their safety.

http://fortune.com/2015/05/08/faa-drone-rules/

http://www.businessinsider.com/amazon-drone-patent-delivery-plans-2015-5

It will be just matter of time for companies to realize the powerfull combo that these 2 new transport technologies can give us.