Mooney and Rolls Royce

[N201MKTurbo]

I have been listening to people talk about how great hydrogen is as a fuel for a long time. First and foremost there are no hydrogen mines, you have to make it. It takes more energy to make the hydrogen then you can ever recover from using it. The second thing is energy density. Even liquid hydrogen has less energy per pound or by volume then jet A. It is far easier to make a tank for jet A then liquid hydrogen.

People are always bragging about making things run on hydrogen. A friend of mine did his masters thesis and project about making a lawn mower run on hydrogen! BFD, any hillbilly could have done that!

And hydrogen fuel cells are wonderful things, the most efficient way to turn fuel into mechanical energy by a factor of three. The problem is they are extremely expensive and fragile. Everything I've read about them says that one false move and they will melt down like Chernobyl. And don't forget about Apallo 13 it's hydrogen fuel cell system blew up, specifically an oxygen tank made by Beechcraft.

[N201MKTurbo]

9 minutes ago, neilpilot said:

Careful with your units.  KW/hr has no meaning. It is just the way that the uninformed sometimes write kWh.

 

Well you are a smart guy, you figured out what I meant. I was just to lazy to look up the correct units abriviation. Besides, wouldn't  a thousand watt hours be the same as a thousand watts for an hour? 

[neilpilot]

Just now, N201MKTurbo said:

Well you are a smart guy, you figured out what I meant. I was just too lazy to look up the correct units abriviation. Besides, wouldn't  a thousand watt hours be the same as a thousand watts for an hour? 

Only for exactly one hour.

[aviatoreb]

30 minutes ago, N201MKTurbo said:

I have been listening to people talk about how great hydrogen is as a fuel for a long time. First and foremost there are no hydrogen mines, you have to make it. It takes more energy to make the hydrogen then you can ever recover from using it. The second thing is energy density. Even liquid hydrogen has less energy per pound or by volume then jet A. It is far easier to make a tank for jet A then liquid hydrogen.

People are always bragging about making things run on hydrogen. A friend of mine did his masters thesis and project about making a lawn mower run on hydrogen! BFD, any hillbilly could have done that!

And hydrogen fuel cells are wonderful things, the most efficient way to turn fuel into mechanical energy by a factor of three. The problem is they are extremely expensive and fragile. Everything I've read about them says that one false move and they will melt down like Chernobyl. And don't forget about Apallo 13 it's hydrogen fuel cell system blew up, specifically an oxygen tank made by Beechcraft.

Well - the sun runs on hydrogen.  It seems pretty powerful.  I wish I could run my Mooney like that.  

Edited June 5, 2016 by aviatoreb

[N201MKTurbo]

Just now, aviatoreb said:

Well - the sun runs on hydrogen.  It seems pretty powerful.  I wish I could run my Mooney like that.  

Well some of the best minds in the world have been working on that for a long time. There are difficult problems to solve like the amount of tritium on this planet, how to extract energy from the device, how to overhaul the device after it has gotten all distorted from heat and radiation and is too radioactive for any human to get anywhere near it. 

[aviatoreb]

20 minutes ago, N201MKTurbo said:

Well some of the best minds in the world have been working on that for a long time. There are difficult problems to solve like the amount of tritium on this planet, how to extract energy from the device, how to overhaul the device after it has gotten all distorted from heat and radiation and is too radioactive for any human to get anywhere near it. 

Eh tritrium is so 1970s.  I want a good hot plasma and a strong magnetic field to hold it, all in a reactor the size of a thermos that will easily run a Mooney for a lifetime of nonstop flying on a thimble full of water as an inert way of carrying the hydrogen.  Radioactivity?  All in the name of good range, I am sure we won't mind a little radioactivity.

[N201MKTurbo]

1 minute ago, aviatoreb said:

Eh tritrium is so 1970s.  I want a good hot plasma and a strong magnetic field to hold it, all in a reactor the size of a thermos that will easily run a Mooney for a lifetime of nonstop flying on a thimble full of water as an inert way of carrying the hydrogen.  Radioactivity?  All in the name of good range, I am sure we won't mind a little radioactivity.

We just have to get the one off the back of the Deloren...

[Hank]

2 hours ago, N201MKTurbo said:

I have been listening to people talk about how great hydrogen is as a fuel for a long time. First and foremost there are no hydrogen mines, you have to make it. It takes more energy to make the hydrogen then you can ever recover from using it. The second thing is energy density. Even liquid hydrogen has less energy per pound or by volume then jet A. It is far easier to make a tank for jet A then liquid hydrogen.

People are always bragging about making things run on hydrogen. A friend of mine did his masters thesis and project about making a lawn mower run on hydrogen! BFD, any hillbilly could have done that!

And hydrogen fuel cells are wonderful things, the most efficient way to turn fuel into mechanical energy by a factor of three. The problem is they are extremely expensive and fragile. Everything I've read about them says that one false move and they will melt down like Chernobyl. And don't forget about Apallo 13 it's hydrogen fuel cell system blew up, specifically an oxygen tank made by Beechcraft.

Vehicles operating in Earth's atmosphere won't need oxygen tanks to run a hydrogen fuel cell, the atmosphere is chick full of it! Apollo used oxygen tanks because they left the atmosphere . . . If the O2 tank is the biggest problem, bring in the fuel cell. 

But it's not. A serious problem is the hydrogen. It's difficult to keep it at -423°F so it will stay liquid, so most of them just use a high pressure tank. Which if punctured in an accident becomes a rocket as the hydrogen shots out the hole. If it hits anything hit enough, the tank becomes instead a flaming rocket . . . Boy, think of the excitement that would add to the 5PM road race going home!

[bonal]

As a fuel for heavy lifting hydrogen is pretty lame. The problem is not the fuel but the stupid political save the planet folks that hate fossil fuels. Most of the alternative sources on locomotion end up consuming more energy than they save. Hey if you want to drive a Tesla knock yourself out I think they are pretty cool cars. But don't kid yourself as someone that works in the electric utility industry those things eat a lot of energy. I have to say this because I heard there is an attempt to pass legislation in California to make it illegal to denounce or dispute any Global warming science or theories. As a huge fan of internal cumustion what can I say we all like what we like.

[Hank]

Don't worry, goofball laws in California can't contradict the Constitution, whose First Amendment covers what is generally known as "free speech." Say whatever you want, and don't worry about it, as long as you aren't conspiring to commit criminal acts or inciting a riot.

[Samurai Husky]

Well this is why electric is so exciting; I will use the Siemens numbers from here http://www.flyingmag.com/aircraft/siemens-unveils-260-kw-electric-aircraft-motor and http://www.gizmag.com/siemens-world-record-electric-motor-aircraft/37048/ which confirms that it produces 348hp at 2500rpm; The other article said that it produced performance 'like' a 350hp engine, which is not the same thing.

If you were to translate that into actual performance, lets look at what the max performance of a IO360:    205 HP @ 2900 RPM or 371ft/lb of torque. In a airplane torque is everything. 

Now lets compare that to the electric motor above: 350HP @ 2500RPM = 735ft/lb or torque. Which means that this motor can effectively be run at 50.4% power (177HP at 2500RPM) and achieve the same torque performance. This is because the performance curve of an electric motor is near perfect linear to the amount of power given. Also it was designed for larger passenger planes, not the GA community.

With that given, 260KW/2 = 130kw/hr of continuous output at the same speed as the IO360; 

Now the Volt has a gas generator that outputs 75kw/hr; so 2 of those would more than make up for its ability. The best i could find out is that the ICE for the volt is about 220lbs. You can actually buy one from GM for about $3400. So 2 of those would get you your 150kw/hr.

To the best i can find, this engine uses 1.4 gallons per hour at peak performance (Which sounds about right) x 2 and its about 2.8Gal hr. 

So lets bring it all together. 

440lbs for the engines; assuming we want to break bladders and get 10hrs of run time, which would be 28gal of fuel or 168lbs; 114lbs for the electric motor (per the article). 

total weight = 440+168+114 or 722lbs with full tanks. 

the IO360 weights in at about 332lbs lets assume full tanks @ 64gal =360lbs or 692lbs total. 30lb difference....

But your gain is in performance, because this is assuming you are running the electric motor at 100% the same performance as the IO360 at 100% performance. So speed being equal lets look at fuel burn. I dont have the numbers exactly, but i remember something like 16.5gal /hr? or about 3.8hrs of full speed run time for the IO360; Yes, it can be leaned for better performance, but lets not get into that right now.

Now if you were paying attention, you might have noticed that the 2 motors output 150KW/hr where in my calculations i said the equivalent to match the performance of the IO360 would be 130kw/h; This means there is an extra 20kw/h of excess power available or about 7.7%; This can be used as boot or recharge or just more power (it also means that fuel consumption is closer to 2.5g/h not 2.8). 

The next thing i am sure someone will bring up is the weight of a battery pack; Sure the volts 16.5kw pack is about 400lbs; but we are assuming we want to run the motor on battery. My argument is that is a waste of space and weight. Assuming you need 130kw for full speed, should a generator fail you will be -75kw, meaning you will need to make up 55kw/h. The volts battery pack is only 16.5kw and weighs in at 400lb. This is why i say its pointless to even look at batteries as fuel storage.  We dont need full speed to stay air born. We can probably assume 50% will keep you up in the air; So really we need 130/2 or 65kw to stay 'up'; So 1 motor would actually do it. But lets say we need 'some' boost with 50%; we would need something like .9kw per minute of flight to make up the missing 55kw we lost on 1 motor failure. So a 5kw battery pack would buy us about 6 minutes of full speed flight with 1 generator working(gen1 at 75kw battery at 55kw/h). or 4.5 minutes of 50% (64kw) flight in the event of both generators failing. This comes out to be about an additional 111lbs of batteries; which i would sell as an 'optional' feature.

You lose both generators in flight 5kw will probably buy you several times more minutes in the air at reduced power setting. IE glide+10% power to just 'extend' you glide time. 

The idea is to show how inefficient aviation engines are. Even with 2 separate generators, the efficiency almost doubles. 

Well this went on longer than i thought it would its something i have been thinking a lot about since getting in to flying, so its nice to put it on paper. 

[N201MKTurbo]

Hay, I've got this device you can put on your carburetor that will double your gas mileage. 

It was advertised in a secret ad in the back of the Popular Mechanics. Don't tell the oil companies!

[jetdriven]

We have a deposit on a Tesla 3. Similar performance to my BMW, no gasoline.  I'm buying. 

[Guest]

9 hours ago, N201MKTurbo said:

Hay, I've got this device you can put on your carburetor that will double your gas mileage. 

It was advertised in a secret ad in the back of the Popular Mechanics. Don't tell the oil companies!

When you get it working on fuel injected engines, I'll become your Canadian distributor.

Clarence

[1964-M20E]

Samurai Husky

 

Great write up you must have engineering in your blood or be an engineer.  One thing I did notice is that you do not account for altitude in you power from the generators (maybe turbo charge them for maximum power up to 18,000).  I like the dual generator aspect and the electric motor. Maybe we could use two electric motors (80kW each) series together so that you would have two truly independent systems with one prop.  I have often thought of some type of hybrid design even using fuel cells running on alcohol but that technology is really expensive.

The other thing is W&B with the two generators and where do you put them?  Maybe one in the tail behind the baggage compartment if that does not throw the W&B off too much.  As for gross weight at 3GPH 23 gallons give you 7 hours of flight time with a small reserve and you stay weight neutral for the current IO360.  The added torque could well overcome the added weight for takeoff and like you said loosing one generator would give you half power which could keep you aloft and or extend you glide to a safe airport environment in many cases.  With that in mind I say forget the batteries not necessary.  However, these are details.

How much is the 260kW electric motor?

Once the FAA got hold of the $3,400 generator from GM it would cost us probably $25,000 each.

 

EDIT

I was thinking about the fuel consumption for the Chevy Volt generators @ 1.5GPH per 75kW unit.  This seems to be light I could be all wrong but that is my impression.

 

 

Edited June 7, 2016 by 1964-M20E

[Samurai Husky]

You could probably get away with 1 turbo for both generators since both generators are only 1.5L each. Even then i am not sure a traditional turbo would work as they are normally powered by the exhaust system. Burning 2.5gal/h would not release enough gas to spin the turbo unless it was very small and the gas is compressed in which case then you have back pressure issued. You would be better served by a electric motor fan system, or a ram air system. 

I think you could put all of the generators and the electric motor up front. I know thats about 530lbs, but you can balance the plane by putting a small battery pack in the tail. From what i can tell, the engine is about 32"l x17:w x 24"h (i went out side and just used a tape measure, so i could be off on this, more so on the height) So i would think they could fit side by side behind the electric motor. Whats nice is that they are inline 4's, so its a pretty small engine.

So no pricing on the 260kw motor yet, its still in development. Hopefully it sees the market one day. The problem is the Lycommings and Continental have no reason to jump on technology like this. They make plenty of money overhauling an providing parts for their existing fleet of engines, which do require a lot of maintenance. 

With the electric motor, you probably have a good 100000hrs before overhaul; the 2 gas generators, probably around 3000hrs, which gives it about a 200k mile equivalent rating. It could be longer, there is no good information out there on how long they last, i would imagine a lot longer than a standard car engine since they are designed to operate at fixed RPMs. Also smaller engines tend to last longer as the forces acting on them are much lower.  

As far as cost of the generators go. It depends how much money is put into certifying them for aviation purposes. Unlike aircraft engines where you only need 100-200 per year, these are in mass produced vehicles, and so 100k-400k are made each year. That keeps the costs way down as the economies of scale kicks in. 

Again all of this is what could be done today. If you research what they are doing with rotary engines for the purpose of generating electricity, then the prospects get 10x better. There are already 3kw rotary engines that weigh in at 30lbs (the engine is only 8lbs, the rest is the copper coils) (though its being used for DARPA); They said scaling up would be no problem and are looking into the electric car market. http://liquidpiston.com/ 

[mccdeuce]

In order to keep efficiency at high altitudes a micro gas turbine instead of a turbo ice.

Overall weigt would be down with potentially slightly higher fuel burn, but utilizing already available jet fuel. 

Wrightspeed is utilizing small turbines for range extension and recharging batteries. 

Capstone Turbine is producing 40kw turbines so you would need 3 to give the same output. 

[Samurai Husky]

The capstone product weighs 800lbs, which is fine for a bus, not so great for a plane. 

The Wrightspeed looks interesting, 80kw @250lb though is still a bit much than what the volt is already using. Also the problem with turbines is that since they spin at exceptionally high rates (100k rpm in this case) things can go south very fast. They need to be inspected more often and repaired more often than a standard ICE. You would probably also want 2 in serial pointing in opposite directions in order to counter the turning forces. 

[Guest]

When 100LL goes to $15.00 per gallon we may see some action with electrics. Until then we'll keep burning dinosaurs.

Clarence

[Piloto]

A birthday cake candle produces more energy than a AAA battery for less weight. Burning fuels have a higher energy density than any battery. That is why first submarines were diesel/electric powered. It is hard to beat combustion motors, specially in heavy applications such as cruise ships, airliners, trucks, earth moving equipment, rockets and others. Combustion motors will be with us for a while. Next improvement possible would be with solar cells for home and charging your car battery. But for practical aircraft there is not enough wing area for solar cells even if they were 100% efficient. No night flying or in IMC allowed. And Hydrogen fuel cells are no better than gas engines.

We are lucky to live in a planet with so many resources. Just imagine trying to make a flying machine on Mars or the Moon with no atmosphere or oil to burn. Not even trees to make the wings.

José    

[bonal]

I'm definitely a fan of a true diesel electric but it's much easier in a car that requires less than 20 hp to maintain 60mph. Gives lots of opportunities for battery recharge also kinetic energy on braking and going down hills. I love internal combustion. Pistons rotors and turbines. Vroom vroom. And all those different exhaust sounds Porsches Ferrari Big Detroit Iron rice rockets turning 16k RPM yes even a well built S and S vtwin. Electric yes can be very fast but no soul no soul at all.

[bonal]

Oh and let's not forget the sweet sound of the Rolls Merlin or a monster Pratt double wasp 18 cylinder.

[Hondo]

Disruptive technology may be closer than we expect.    https://www.youtube.com/watch?v=Kxryv2XrnqM&feature=youtu.be

 

[ChrisH]

Actually, this is the most exciting use of electirc motors for GA that I've seen. Take this over a chute any day.

http://axteraerospace.com/

he AXTER System is the first hybrid system designed for general aviation that sum up 40 hp (30Kw) extra power to the combustion engine for short takeoffs, high rates climbing or to compensate the engine loss power in hight temperature conditions.


Furthermore, the AXTER System keeps you flying for 7 minutes in case of engine failure, and this extratime can be managed as required by the pilot, for instance take land in a safe place or returning to the aerodrome in case of main engine failure during takeoff. You can take part of the stored energy for landing or taking the plane to the maximum glide speed to have more flight time.

Only in the electric mode, the aircraft (Tecnam P92J), is able to climb up to 200ft/min at 135km/h. When the AXTER System is not being used, it charges the battery, so they are fully charged. When taxiing or aproaching the airport, the system saves fuel and engine maintenance hours as it is the electric motor of AXTER System that moves the aircraft. All technology has been developed exclusively for aviation. The system is already certified in Spain and we are working to obtaining the European certification.

The system is commercialize in kit and can be built up in any aircraft carrying the Rotax 912 and 914 engines installed.

[1964-M20E]

Neat 40 hp extra would be nice on the climb out and takeoff roll as well as extended glide distance with the electric.  Like you said better than a parachute.  40hp would not get you any climb in the Mooney so power failure on take off would still be bad.  Maybe enough power to make the impossible turn though.