Jump to content

Recommended Posts

Posted
7 hours ago, N201MKTurbo said:

You notice they don’t fly it any higher than they are willing to crash and always over nice soft sand.

Ain't nothing soft when you hit it at a hundred mph . . . .

Posted
4 hours ago, Hank said:

Ain't nothing soft when you hit it at a hundred mph . . . .

I used to go out to the Imperial sand dunes pretty regularly. I’ve done some pretty horrific crashes in the sand. You only get hurt if the machine lands on top of you.

Posted

Although Jetson doesn't mention it on their website, it looks by the weight and speed restrictions that they intend it to be operated under part 103. This precludes it from almost all the intended uses listed on their website. They mention using it to commute to work. This would only work if you were commuting from your farm house to your farm out in the sticks.

  • 3 weeks later...
Posted (edited)

The HP required to fly with x weight is and has been well known for a very long time.

The most inefficient flight is vertical, that’s why helicopters require so much engine power. 300 HP in a helicopter to carry what 100 hp can in an airplane.

Yes you can build a quad copter to take a little 90lb girl on a 10 min flight, but you can’t build one to take two 200 lb men across town, not battery powered anyway.

Which brings me to one of two conclusions.

1. Either these people are stupid or think that any day now a magic battery will come into existence that will contain 10 times the power of current batteries.

2. These things are scams, and in fact I believe there has been huge amounts of money garnered from big companies, so people of course believe if Honda for example is looking into it, it must be plausible, then the FAA piles on issuing rule making on EVTOL heliports, again making people believe any day now it’s coming.

Just look at the numbers. My Tesla battery pack is 50 KWH and weighs in the neighborhood of 1,000 lbs, there is additional weight for cooling, but ignore that for now.

So how much gasoline does it take to replicate the 1000 lb Tesla battery pack? Gasoline has 33.7 KWH of energy in it so the answer is 1.5 gls of gas is 50 KWH. 1.5 gl of gas is 9 lbs.

I admit it’s not that simple as gas engines are at best about 20% efficient and electric can be as much as 95%, but you just can’t lift the battery, the vehicle and any decent payload for more than a few minutes, ignore the fact that completely discharging a Lithium battery in 10 minutes is hell on its cycle life, generates enormous amounts of heat etc.

Until that magic battery is built this is all wishful thinking.

Elon Musk has stated years ago that he wants to build an airplane, he’s even done the math and published the results. I think from memory he says it will take a 400% increase in energy density to even become remotely viable. That’s from memory so it could be way off.

Edited by A64Pilot
  • Thanks 1
  • Haha 1
Posted

It is amazing that people think that air taxis are something new. They have been available for over half a century using helicopters and airplanes. All they are doing is trying to build a cheaper helicopter with very limited range. Which hasn't been proven to be possible yet... 

Any guesses what the out the door price will be for that UBER helicopter?

Posted

Oh, surely long before EVTOL become realistic there will be electric airplanes, because you can fly much further, carrying more weight at a higher speed in an airplane than you can in anything that can hover.

There is what’s called the square / cube ratio that explains why you simply can’t just scale up anything and have it work, or actually there is a limit to how much scaling works.

Extreme example is a spider can walk on water, but we can’t or an ant can fall from any height and walk away

  • Like 1
Posted
51 minutes ago, A64Pilot said:

Which brings me to one of two conclusions.

1. Either these people are stupid or think that any day now a magic battery will come into existence that will contain 10 times the power of current batteries.

2. These things are scams, and in fact I believe there has been huge amounts of money garnered from big companies, so people of course believe if Honda for example is looking into it, it must be plausible, then the FAA piles on issuing rule making on EVTOL heliports, again making people believe any day now it’s coming.

Concerning #1 above, is there a difference?  (Ignorant vs. stupid, maybe.)  I equate the whole electrification vs. ICE to bad religion and these people are simply true believers.  I just got back from Oshkosh where I ran across a few of these cultists.  For anyone who can do the Math, the claims by these people are hilarious.  For instance, taking the range claim of one Ecraft would have to be done from take-off to landing at 23% power!  Do you know of anyone who recommends less than 100% take-off power, especially in something with only about 80hp?  I do not know if they are intentionally lying, but they sure do freely spew BS from their mouths.

Note that Tecnam just quit trying converting their fixed-wing aircraft to electric power,  https://www.greencarcongress.com/2023/06/20230617-tecnam.html , yet Joby has received almost $1B in funding.  When might that idea pay off?  40 years, once battery technology catches up?

And do not forget Terrafugia.  As I recall, in about 2006, they promised a flying car roadable airplane in three years for $125,000.  A few years later, it was due in four more years at $250,000, and a few years later was due in five years for $375,000.  Now they are Chinese-owned and continue on, yet, with no production...

Airplanes are difficult in so many ways.  Most of the tough problems were solved decades ago, and we are, fortunately, still profiting from those investments.  The potentials gains we should be focusing on right now are relief from regulatory burden from the FAA.  (Why are avionics for Experimental Aircraft so much cheaper?)  As a side note, I have an idea for fuel injectors that should provide better fuel atomization, thus better power and efficiency, but the FAA requirements to even test them makes the idea unprofitable, thus moot.

Posted
1 hour ago, N201MKTurbo said:

It is amazing that people think that air taxis are something new. They have been available for over half a century using helicopters and airplanes. All they are doing is trying to build a cheaper helicopter with very limited range. Which hasn't been proven to be possible yet... 

Any guesses what the out the door price will be for that UBER helicopter?

What is new is the idea of the piloting - computer controlled - AI controlled air taxis.  With that, there is at least the potential for a dramatically different economy of air taxi.

1 hour ago, A64Pilot said:

The HP required to fly with x weight is and has been well known for a very long time.

The most inefficient flight is vertical, that’s why helicopters require so much engine power. 300 HP in a helicopter to carry what 100 hp can in an airplane.

Yes you can build a quad copter to take a little 90lb girl on a 10 min flight, but you can’t build one to take two 200 lb men across town, not battery powered anyway.

Which brings me to one of two conclusions.

1. Either these people are stupid or think that any day now a magic battery will come into existence that will contain 10 times the power of current batteries.

2. These things are scams, and in fact I believe there has been huge amounts of money garnered from big companies, so people of course believe if Honda for example is looking into it, it must be plausible, then the FAA piles on issuing rule making on EVTOL heliports, again making people believe any day now it’s coming.

Just look at the numbers. My Tesla battery pack is 50 KWH and weighs in the neighborhood of 1,000 lbs, there is additional weight for cooling, but ignore that for now.

So how much gasoline does it take to replicate the 1000 lb Tesla battery pack? Gasoline has 33.7 KWH of energy in it so the answer is 1.5 gls of gas is 50 KWH. 1.5 gl of gas is 9 lbs.

I admit it’s not that simple as gas engines are at best about 20% efficient and electric can be as much as 95%, but you just can’t lift the battery, the vehicle and any decent payload for more than a few minutes, ignore the fact that completely discharging a Lithium battery in 10 minutes is hell on its cycle life, generates enormous amounts of heat etc.

Until that magic battery is built this is all wishful thinking.

Elon Musk has stated years ago that he wants to build an airplane, he’s even done the math and published the results. I think from memory he says it will take a 400% increase in energy density to even become remotely viable. That’s from memory so it could be way off.

I do think there could be a place for 3-5 mile flights by quad-copter like autonomous Uber-vehicles.  Then recharge.  That's a very narrow mission but one that does not currently exist and the advent of computer controlled pilots - AI pilots making this possibly more available seems very plausible to me.  In other words, part chemical engineering, part aeronautical engineering, part software engineering for the pilotage and air space separation, and part software-economic innovation in terms of the ride hailing concept in our phones makes this all at least a new kind of thing since what might have been 50 years ago.  Many new technologies coming together.  We shall see.

I am bullish on solid state batteries that seem to be coming - they are 2 to 2.5 times more energy dense in their current concept than Lithium based chemical batteries and they charge much faster too.

15 minutes ago, AH-1 Cobra Pilot said:

And do not forget Terrafugia.  As I recall, in about 2006, they promised a flying car roadable airplane in three years for $125,000.  A few years later, it was due in four more years at $250,000, and a few years later was due in five years for $375,000.  Now they are Chinese-owned and continue on, yet, with no production...

OMG I couldn't agree more.  A flying car is a funny thing like a cartoon character worth having if you are a nutty professor (and I am!) but not appropriate for general consumption.  I mean if I had $375k - you get a crappy airplane that is a crappy car.  And my car gets covered in bugs, salt, snow, .... can you imagine the pre-flight to make sure you didn't get dinged by a shopping cart at the grocery store?  Can you imagine how much that grocery cart dig would cost to repair - talk about hangar rash to the nth degree.

For $375k - I would buy 10 used Subarus and keep them at all my favorite airports, and a nice used airplane and fly between the airports.  And for those airports I didn't already have a car - I would rent a car.  There - problem solved.  I get to drive good cars and fly a good airplane.

  • Like 1
Posted

Electrification of transportation is in my opinion a good thing, but not for the reasons many think.

I think it’s a good thing simply due to efficiency, our Tesla, a safe, roomy pretty quick car can travel in comfort on the energy equal to 1.5 gls of gas.

And by the way the “fuel” cost for us to drive 260 miles is $8.5.

I differ from the cultists in that I think the government should have nothing to do with it, if it’s a superior technology and I think it is, people will figure it out on their own.

As is and what blows my mind is the system that’s set up by the government, the one that says they are for the little guy is to buy wealthy people expensive Auto’s. 

I’d love for an electric airplane to be a reality, sea level power at any altitude, tens of thousands of hours engine life, and near zero maintenance.

But without a huge increase in battery capacity it just ain’t happening. Don’t get me wrong, nobody is an electric fan more than I am, but until the magic battery exists, it’s just not happening

  • Like 3
Posted
Electrification of transportation is in my opinion a good thing, but not for the reasons many think.
I think it’s a good thing simply due to efficiency, our Tesla, a safe, roomy pretty quick car can travel in comfort on the energy equal to 1.5 gls of gas.
And by the way the “fuel” cost for us to drive 260 miles is $8.5.

Let’s not forget that generating electricity has it’s own pollution/carbon emissions. Not all electricity is generated by wind/sun/nuclear power. And manufacturing of wing and solar panels have their own pollution and carbon emissions, nuclear has it’s own environmental problems.
It’s more economical to store electricity and use in cars, but the batteries are a pollution problem as well.
Posted
4 minutes ago, ArtVandelay said:


Let’s not forget that generating electricity has it’s own pollution/carbon emissions. Not all electricity is generated by wind/sun/nuclear power. And manufacturing of wing and solar panels have their own pollution and carbon emissions, nuclear has it’s own environmental problems.
It’s more economical to store electricity and use in cars, but the batteries are a pollution problem as well.

Dont forget hydro!

Posted
16 minutes ago, aviatoreb said:

What is new is the idea of the piloting - computer controlled - AI controlled air taxis.  With that, there is at least the potential for a dramatically different economy of air taxi.

I do think there could be a place for 3-5 mile flights by quad-copter like autonomous Uber-vehicles.  Then recharge.  That's a very narrow mission but one that does not currently exist and the advent of computer controlled pilots - AI pilots making this possibly more available seems very plausible to me.  In other words, part chemical engineering, part aeronautical engineering, part software engineering for the pilotage and air space separation, and part software-economic innovation in terms of the ride hailing concept in our phones makes this all at least a new kind of thing since what might have been 50 years ago.  Many new technologies coming together.  We shall see.

I am bullish on solid state batteries that seem to be coming - they are 2 to 2.5 times more energy dense in their current concept than Lithium based chemical batteries and they charge much faster too.

OMG I couldn't agree more.  A flying car is a funny thing like a cartoon character worth having if you are a nutty professor (and I am!) but not appropriate for general consumption.  I mean if I had $375k - you get a crappy airplane that is a crappy car.  And my car gets covered in bugs, salt, snow, .... can you imagine the pre-flight to make sure you didn't get dinged by a shopping cart at the grocery store?  Can you imagine how much that grocery cart dig would cost to repair - talk about hangar rash to the nth degree.

For $375k - I would buy 10 used Subarus and keep them at all my favorite airports, and a nice used airplane and fly between the airports.  And for those airports I didn't already have a car - I would rent a car.  There - problem solved.  I get to drive good cars and fly a good airplane.

Couple of statements, first I think short trips of less than 10 min isn’t really viable, but then your statement of then they recharge between trips.

OK so where do they recharge? Do they only fly to chargers or do they fly from a charger to you, then to your destination and from there to a charger? How long does a recharge take? Time interval between recharges, IE how do you dissipate the heat, because anyone who has ever repetitively recharged any kind of battery rapidly will tell you that they get hot, quick and heat is battery enemy #1, so you have to deal with that heat, and that adds quite a bit of weight, Tesla does it with copper tubes filled with antifreeze and a heat pump to cool the battery, run the car hard and when you stop you can hear the heat pump and fans running hard, which takes power of course as well as weight.

There are huge problems to solve, current Government promised to spend Billions on electric car chargers, which I’m also against, but where are all these chargers? I haven’t seen any, have you? How many chargers would air-taxis need, and where would these things land and takeoff from? Only thing I can see is roof tops, so then the building is going to have to get a cut of the money.

The expense of point to point air transport would be prohibitively expensive for the average Joe I think, yet I wouldn’t be surprised if his taxes aren’t what will pay for it, just like the current subsidies.

Solid State batteries have been around for longer than fuel cells have and have the same problem, that is unless your NASA they aren’t affordable, and it doesn’t look like they will be in the foreseeable future. Fuel cells were what was promised decades ago to Government agencies to get them to drop the electric car because the major manufacturers didn’t want to have to completely re-tool etc to build something new, more money in continuing with ICE technology.

Solid State is in the group of “magic batteries” when or if the magic battery becomes viable, then sure lots of things will become possible, but I wouldn’t hold my breath

Posted

A guy I used to work with did a lot of work with NASA and other space people. He told me about an electric car competition held here in the Phoenix area back in the early 80s at PIR (NASCAR track). Everybody was building cars with lead acid batteries or Ni-cad batteries. Most of the cars would barely make 40 MPH and 20 miles range. He borrowed an Apollo fuel cell from NASA and his team built a car around it.  After the first day of testing at the track his team was disqualified because they were using fuel. They were out on the track doing hot laps at way over 100 MPH and he said they had about 500 miles of range. Too bad the fuel cell cost a few million dollars....

  • Like 2
Posted (edited)
31 minutes ago, ArtVandelay said:


Let’s not forget that generating electricity has it’s own pollution/carbon emissions. Not all electricity is generated by wind/sun/nuclear power. And manufacturing of wing and solar panels have their own pollution and carbon emissions, nuclear has it’s own environmental problems.
It’s more economical to store electricity and use in cars, but the batteries are a pollution problem as well.

Nukes are the only currently viable option that make sense to me, maybe in the future we could build Solar power stations in orbit and beam the power down via microwaves or something, but not in my lifetime. Panels help, but the sun doesn’t always shine, except in space, and the wind doesn’t always blow, so what’s the plan to cover when the wind and sun aren’t making power? Light candles? One possibility is your electric car, but it’s not real viable in my opinion because the batteries only have so many cycles in them.

Batteries are recyclable, you don’t just throw away all those valuable elements, the cobalt, Lithium etc still is in the battery, it doesn’t go away.

Give free enterprise a chance, when it’s discovers that there is money in those batteries they will be recycled, and efficiently too, because that maximizes profits.

I don’t touch carbon emissions, not saying it’s not an issue, but in my opinion it’s not THE issue, my belief is that every year fossil will become more and more expensive, and it’s just too valuable a resource to just burn. For some reason we understand we can’t burn our forests for energy, but for some reason we think fossil will last forever.

We don’t need to spend our tax dollars on car chargers, that’s short sighted and stupid and I believe there are ulterior motives, there always is when the Government is involved.

What we need to do is start beefing up our electrical generation and distribution capability, chargers are easy and best left to entrepreneurs, exactly like we currently do with gas stations.

Musk is getting rich on his Supercharger network, there is BIG money there, he sells the electricity at I think about three times what he pays for it and the stations require no human involvement, he pays no one to sit at a register, no building, no bills etc. Locally its 34c per KWH at a supercharger, I pay 17c for residential power and I know Commercial gets a big break, so if he pays 12c then it’s right at a 300% profit, for boxes that sit in the corner of a random parking lot.

Why in the world would we think it needs Government subsidies?

Edited by A64Pilot
  • Like 1
Posted
1 minute ago, N201MKTurbo said:

A guy I used to work with did a lot of work with NASA and other space people. He told me about an electric car competition held here in the Phoenix area back in the early 80s at PIR (NASCAR track). Everybody was building cars with lead acid batteries or Ni-cad batteries. Most of the cars would barely make 40 MPH and 20 miles range. He borrowed an Apollo fuel cell from NASA and his team built a car around it.  After the first day of testing at the track his team was disqualified because they were using fuel. They were out on the track doing hot laps at way over 100 MPH and he said they had about 500 miles of range. Too bad the fuel cell cost a few million dollars....

The other problem is the Hydrogen required to operate the fuel cell comes from natural gas, and I think it’s more efficient to burn the gas than it is to make it into hydrogen to then burn if you will in a fuel cell.

Sure you can take electricity and make hydrogen from water, but it’s more efficient to make electricity and use it directly, than to make it into hydrogen, that then makes electricity from the hydrogen.

Nasa uses it because Hydrogen and a fuel cell is lighter than a battery

Posted
1 hour ago, A64Pilot said:

The other problem is the Hydrogen required to operate the fuel cell comes from natural gas, and I think it’s more efficient to burn the gas than it is to make it into hydrogen to then burn if you will in a fuel cell.

Sure you can take electricity and make hydrogen from water, but it’s more efficient to make electricity and use it directly, than to make it into hydrogen, that then makes electricity from the hydrogen.

Nasa uses it because Hydrogen and a fuel cell is lighter than a battery

Hydrogen is not a fuel, it is just an energy storage medium. There are no hydrogen mines, you have to make it.

The electric car mentioned above had a LOX and LH2 storage dewars. Not the safest or cheapest way to fuel a car.

Posted
2 hours ago, aviatoreb said:

I do think there could be a place for 3-5 mile flights by quad-copter like autonomous Uber-vehicles.  Then recharge.

This seems obliquely analogous to range anxiety in EVs.  In 2001 the average daily mileage in this country was something like 33 miles.  At the time, it appeared to be shrinking and, by 2015 was down to something like 26 miles.  So why all the anxiety around a Tesla that will "only" go 300 miles on a charge?  For most people, if you plug it in when you get home, you never have to think about it.  Certainly, if you drive from Tampa to Los Angeles, you need to do some planning, but apparently a fairly small fraction of Americans do (either of those).  I can think of a large number of use cases for 3-5 mile trips at the right price.  On the other hand, averages can be deceiving, so the low average automobile trip mileage may not tell us much.

Posted (edited)

EV’s aren’t for everyone, I don’t think they work nearly as well in extreme cold and if you live in Montana or other very sparsely populated place there likely isn’t and probably won’t be a charging infrastructure, maybe. In an ICE car heat is free, it’s just taken from the coolant, but an EV has to use it’s battery to provide heat and in real cold a heat pump isn’t efficient, so I’ve read that in real cold that you can increase power consumption by 30%.

But for over 95% of people they are fine. If you want to go on a long trip like from Fl to Maine or something you just tell the car “Navigate to Maine” and in a few seconds it calculates every stop you need to make and tells you how long you need to stay at each stop, it also knows from the internet that each stop is operational and how busy it us, and will route you to less busy ones if needed. When you get to the charge point you just plug in, the car is known by the charge point and the card you have on file is charged. Average stop is 15 to 20 min and on average you only charge to 60, maybe 70% or so because the higher the state of charge, the slower it charges, so the cars computer calculates how much needed to get to the next point and frequency of charges to minimize time charging. You don’t have to do any planning, just drive. This “range anxiety” is a figment of the news and I guess cars that don’t have a charging network I guess, but for a Tesla it’s a non issue, really, unless you live in Montana or similar.

If you choose to you can stop at Motels with level 2 chargers and plug in so your fully charged when you leave the next day, many are free because on average it’s only costing them 5 to 10 bucks max. I’ve never bothered myself so I don’t know.

Usually chargers are located where a convince store or coffee shop is, so by the time you get a sandwich or coffee or whatever it’s time to go. My Wife walks the dog, just enough time for that. You probably do stop about twice as often as a gas car because you’re not using a full battery like a gas car can use its whole gas tank, you only use maybe 2/3. The computer calculates it so you arrive at the next charger with a near dead battery, that makes me nervous so I always charge a little higher than it says to.

You’ll make it, but arriving with 5% charge is just pushing it too much for me.

If you do a lot of long distance driving then an EV may not be for you, but very few of us actually do, and the advantages of an EV just make it better, like never having to stop at a gas station, the ability to program the car so that the inside is at your preset temp when you leave, or the ability to leave the AC on while your shopping, to be able to leave the dog in the car while your getting groceries etc. I have ours so that the inside temp never goes above 95F, while she is at work the AC runs as necessary to keep it at 95 or so. I think that helps keep the interior in better shape.

But really the best part of it is plugging in when you get home and every morning leaving at the % charge you selected, it’s best to not charge above 90% for longevity of the battery, I use 70%. But not having to stop at a gas station a couple times a week on the way home from work is priceless, to say nothing of the fact that it only cost about 1/3 of what it would to drive a comparable ICE car.

So in my opinion we are there for cars. Aircraft? Not so much, it’s a much bigger deal to let down out of altitude, shoot an approach if IFR just to charge and go again, doing that would kill trip time, so for an airplane it would need as much flight time as a fossil fuel airplane and with 1.5 gls of gas taking 200 lbs of battery to equal, (I’m taking in the 20% to 95% efficiency difference) still we aren’t even close. Assuming that number is correct then my 54 gls would take 7,000 lbs of battery to replace, and that’s not viable.

 

Edited by A64Pilot
  • Like 1
Posted
7 hours ago, A64Pilot said:

Just look at the numbers. My Tesla battery pack is 50 KWH and weighs in the neighborhood of 1,000 lbs, there is additional weight for cooling, but ignore that for now.

So how much gasoline does it take to replicate the 1000 lb Tesla battery pack? Gasoline has 33.7 KWH of energy in it so the answer is 1.5 gls of gas is 50 KWH. 1.5 gl of gas is 9 lbs.

Those numbers seem off.

About 750 watts is 1 HP.  So 50 KWH is about 66 HP for 1 hour.

My engine produces about 136 HP on 10 GPH.  So about 100,000 watts of power.  So 1 gallon of fuel is 10 KWH.  

Posted (edited)
9 minutes ago, Pinecone said:

Those numbers seem off.

About 750 watts is 1 HP.  So 50 KWH is about 66 HP for 1 hour.

My engine produces about 136 HP on 10 GPH.  So about 100,000 watts of power.  So 1 gallon of fuel is 10 KWH.  

Following chart is from here, there are other sources of course, which I guess explains where 33.7 came from, but .4 and .7 are close, look at the KWH / gal column

However I believe this is at 100% efficiency and an aircraft engine isn’t anywhere near 100% efficient, the Tesla Model 3 motor is about 95% efficient as is I believe about as efficient as it gets currently. It’s how inefficient a gasoline or any other ICE is that’s a large part of the problem

https://en.wikipedia.org/wiki/Gasoline_gallon_equivalent

Fuel: liquid, US gallons GGE GGE % BTU/gal kWh/gal HP-hr/gal kcal/litre
Gasoline (base)[9] 1.0000 100.00% 114,000 33.41 44.80 7,594.1
Gasoline (conventional, summer)[9] 0.9956 100.44% 114,500 33.56 45.00 7,627.4
Gasoline (conventional, winter)[9] 1.0133 98.68% 112,500 32.97 44.21 7,494.2
Gasoline (reformulated gasoline, E10 - ethanol)[9] 1.0193 98.1% 111,836 32.78 43.95 7,449.9
Gasoline (reformulated gasoline, ETBE)[9] 1.0196 98.08% 111,811 32.77 43.94 7,448.3
Gasoline (reformulated gasoline, MTBE)[9] 1.0202 98.02% 111,745 32.75 43.92 7,443.9
Gasoline (10% MTBE)[10] 1.0179 98.25% 112,000 32.82 44.02 7,460.9
Diesel #2[11] 0.8803 113.6% 129,500 37.95 50.90 8,626.6
Biodiesel (B100)[12] 0.9536 104.87% 119,550 35.04 46.98 7,963.8
Biodiesel (B20)[11] 0.8959 111.62% 127,250 37.29 50.01 8,476.7
Liquid natural gas (LNG)[11] 1.52 65.79% 75,000 21.98 29.48 4,996.1
Liquefied petroleum gas (propane / autogas) (LPG)[11] 1.2459 80.26% 91,500 26.82 35.96 6,095.3
Methanol fuel (M100)[11] 2.007 49.82% 56,800 16.65 22.32 3,783.7
Ethanol fuel (E100)[11] 1.498 66.75% 76,100 22.30 29.91 5,069.4
Ethanol (E85)[11] 1.3936 71.75% 81,800 23.97 32.15 5,449.1
Jet fuel (naphtha)[13] 0.9604 104.12% 118,700 34.79 46.65 7,907.2
Jet fuel (kerosene)[13] 0.8899 112.37% 128,100 37.54 50.35 8,533.4
Edited by A64Pilot
Posted

But my airplane does 62% power (136 HP) on 10 GPH.  So 13.6 HP-hour per gallon.

Which means 30% efficiency with your number.

But I am trying to figure out how a Telsa does 300 miles at say 50 MPH, so 6 hours, using 67 HP-hour.  So Telsa cruises on 11 HP?

Posted

If you really want to get into the weeds with a Tesla, there is a site called Teslafi that downloads data from your car and you can really get into the weeds, attached are the efficiency of the car vs OAT and speed, speed isn’t efficiency but consumption in watt hours per mile.

 

IMG_1494.png

IMG_1493.png

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.