# Would you purchase a electric plane kit with the following specs?

Discussion in 'Hangar Flying' started by annerajb, Jul 24, 2016.

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1. Jul 24, 2016

### Jon Ferguson

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I think the only electric aircraft that have even a remote chance of having some purpose and utility are going to have to be designed from the ground up to be electric.

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2. Jul 24, 2016

### gtae07

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Exactly. The 172 is a terrible choice for electric conversion. Too heavy, too draggy.

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3. Jul 24, 2016

### cheapracer

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China is the place to look at the moment, not because of the standard cheap manufacturers in recent times blah blah, but because the last "5 year plan" just ended, saw the Government invest a lot in electric car research and development and there's a bit of stuff starting to come through now from that.

I'm going to try to understand how a Prius system works, I actually understand the very clever gearbox (that they may have stolen from an Australian Inventor), but not how the electrics are integrated, and with the amount of used Priuss around the world, I think that may be worth the investigation.

There's been some 200,000 Nissan Leafs sold so there must be one or two crashed ones by now also.

There are hundreds of electric micro cars running around Chinese cities now due to the mentioned 5 year plan investment grants for their development, not sure if they are modern tech or old tech, will look at the ones for sale out front of my factory tomorrow and try to get some specs, you've piqued my interest a bit.

I am due to look at a brand new hybrid engine when I get around to it, 3cyl, 45hp, 50kgs including the big genny on the end of it. I don't know if the weight includes controller and cables though ... obviously not batteries.

4. Jul 24, 2016

### cheapracer

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Your Grandchildren won't see the end of oil, since the Saudi's started strangling everybody 15 - 20 years ago, the search for shale went full steam ahead and there's now known huge deposits to hand. It was economical to process it with the price of the barrel a few years ago and these discoveries and investments are what drove the price of the barrel way down recently. Fortunately a few Americans have had a gutful of being strangled by the Saudis and have continued some investment in shale but now Iran is able to sell again it may be a while as there's a glut right now. Ironically the Saudi's themselves are sitting on some of the largest reserves of shale that they didn't know were so large. But there's big deposits elsewhere including America and Canada, with Brazil close by.

What's driving electric and other alternate powered vehicles is the Climate Change stuff.

5. Jul 24, 2016

### Manticore

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Hmmm. Let's see. That works out at nearly 250 60Ah 12v deep discharge batteries (assuming 100% efficiency). I'm not even going to bother calculating the weight.

6. Jul 24, 2016

### Lucrum

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No.

7. Jul 25, 2016

### DangerZone

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Half an hour of flight from my home airport there's a guy who converts Cessna 172s to Centurion Diesel 155HP engines. The range is increased, the price of fuel is three to four times lower, the engine runs smoothly and the aircraft is still certified for flying schools orwhatever you wanna do with it. The conversion costs around €40k complete ready to fly, so if we'd add a decent airframe for 10k, we'd have a nice little 'green' Cessna 172 for under €50k.

Concerning charging, the 50A 240V charger needs a strong fuse and this is the maximum that the grid allows for small households withoutthree phase electricity. Anyone wanting to charge at 100A/240V for prolonged time needs to have 3-phase current installed at their home, and 99% of homes in Europe (on average strongest installations in the world) don't have that. In other words, you would need an infrastructure to power the electric airplane at that rate. So you can pretty much forget USA/Canada as the market since the standard is 110V at 25A to 50A max since people would have to invest into the electric grid to charge this airplane's batteries. And you'll see that most pilots are practical when it comes to cost: everyone wants to fly cheaper than what they used to before, not more expensive.

For flight schools, it would make no sense. Electric aircraft are great for their simplicity and excellent running. Get a pilot student used to this simplicity and the moment he tries to fly a gasoline Cessna 172 he/she'll get cofused by the standard operational procedures he would have to perform. Even following the check list would be a nightmare, checking the magnetos and all other stuff we usually do before taking off. Sure, the flight school MIGHT save some money they'd spend on gasoline (or jet fuel if they have the diesel Centurion/Continental conversions) but safety would definitely be a practical problem if the student tries to fly a non-electric Cessna at another club.

In conclusion, your electric price SHOULD be less than $50k to be able to compete, your installations should be taken into consideration and the safety issues must be resolved. Concerning electric motor conversions from automotive electric motors - forget it. It would be like thinking a tractor diesel engine could be retrofitted to fly an airplane. These motors are too heavy, unadapted for sustained flight and too inefficient for aircraft use. There is also no point in doing that, aviation electric motors are inexpensive. Yet good luck in finding cheap controllers or batteries, that's the real cost of electric flying. 8. Jul 25, 2016 ### DangerZone ### DangerZone #### Well-Known Member Joined: Sep 5, 2011 Messages: 2,098 Likes Received: 369 Location: Zagreb HR Could it have been just another story like the 'communist threat' to get the right funding..? Biodiesel has been produced for more than half a century and sinthetic fuel production is a century old formula. With more and more oil fields discovered on a daily basis, the risk of 'running out of oil' gets as credible as a fairytale. On the other hand, Elon Musk seems to be serious about building a battery megafactory. If he'd really manage to get the battery cell price down to 25% of what they cost now, that might really be a game changer for electric flight. cheapracer likes this. 9. Jul 25, 2016 ### cheapracer ### cheapracer #### Well-Known Member Joined: Sep 8, 2013 Messages: 5,049 Likes Received: 3,327 Location: Australian Link to cheap electric aviation motors not loading .... 10. Jul 25, 2016 ### litespeed ### litespeed #### Well-Known Member Joined: May 21, 2008 Messages: 1,329 Likes Received: 216 Location: Sydney Would I? Not at that price, range, load and never with that airframe. It needs to be sleek to have a much lower power need and thus greater range. And it needs to be a lot cheaper. I agree with Bex, the car batteries from electric cars will be the beginning of cheap affordable systems that just need a aircraft designed motor and a designed from scratch for the purpose airframe. The idea of sustained long flight from electric is possible but a hybrid approach is much more likely to meet our needs and safety expectations. Given that solar cells are now been developed that are super light and flexible with good power output- the future is bright. A good airframe with big wings covered in cells, a small engine with generator and a smallish load of lithium cells and a good electric motor could be the ideal system. 11. Jul 25, 2016 ### JIC ### JIC #### Well-Known Member Joined: Dec 31, 2010 Messages: 290 Likes Received: 43 Location: Middleton, Idaho No,$150 thousand for one hour-forty five minutes of flight time, no way.
It would be like my friends electric car, can barely make the 20 miles to my place
and back home again.

jic

12. Jul 25, 2016

### DangerZone

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13. Jul 26, 2016

### Riggerrob

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Yes, if it would carry a pair of 95th percentile men and cruise for more than two hours. I stand 6 feet tall and weight more than 200 pounds. When wearing a parachute or winter parka, I grow even more bulky. Most of my pilot friends are close to my size and I prefer dating women almost as tall as me.

Pipistrel and Yunik (sp?) have already flown credible electric airplane prototypes.
Flying schools will be the first to adopt electric-powered airplanes but line-boy duties will shift to plugging in fresh batteries and carrying old batteries to the charger in the hangar. An electric golf cart will greatly reduce the muscle needed for transporting batteries.
As soon as three or more flight schools per state adopt electric-powered trainers, schools will schedule student cross-country flights to visit other schools that cooperate in a battery-sharing agreement.
As battery controllers increase in sophistication, ATC will be able to read battery capacity and will refuse take-off clearance to student pilots whose batteries are discharged too far.

We may have passed "peak oil" back in 2008, but we will never pump the last drop of oil from out of the ground. Once most the shallow "sweet crude" has been pumped out of existing wells, prospectors will move farther afield in search of new types of oil: Alaska's North Slope, off shore oil, Alberta Tar Sands, shale, etc. We can always find another source of oil, but every new source will be more expensive to drill, transport and refine than the last until only wealthy warbird owners will be able to afford to fly.
Meanwhile, working class will ride to work on electric motorcycles, electric buses or electric automobiles and wonder why airplane's are still burning "stupid expensive" gasoline.
First generation electric-lowered trainer airplanes will be simply stock Cessnas and Katanas with firewall-forward conversion kits containing an automotive electric motor, a fancy controller and enough batteries to balance. If they need to increase range, they will bolt a second battery tray in the baggage compartment.

14. Jul 26, 2016

### Pops

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Where does all of that electric come from? At the present, 45% of the U.S electric production is being shut down with the demand going up. Gasoline is not stupid if there is nothing to replace it. Going to nothing is stupid. Wind and solar, it will be a long time until there is a economically way to store the power for use on days of no wind or sun.

I have a stand- a- lone solar system for my home and have about a \$35 a month grid electric bill because electric is going to get very expensive and rationed with the use of smart meters. Supply and demand.

15. Jul 26, 2016

### DangerZone

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Years ago, the Slovenian company Pipstrel demonstrated electric glider aircraft trailers with roof solar panels. While flying with one pair of batteries in the glider, the other batteries were charged by the trailer solar panels. When soaring would be finished, the pilot could simply land besides the trailer, change the batteries and fly off again up to 1500ft AGL to continue soaring. The aircraft hangar also had the roof covered with solar panels. In other words, this means full energy production on site.

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16. Jul 27, 2016

### annerajb

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I wish conversions like that Centurion Diesel would be more common in the US.

About charging the Tesla HPWC (80 amps) charger is frequently installed at homes across the US without needing three phase. You are corrects that it needs strong fuse but a 80A HPWC only needs a 100 Amp fuse and most residential service is 200 Amps. Regardless on Hangar I did a search a few weeks ago and it was common to find T-Hangars with 200 amps service per hangar. That would be more than enought to have a 80A charger and plenty left over.

I agree that the pilot will need some sort of transition training but probably not a lot different than flying a different airframe or going from a old C-152 into a new C-172 G1000. Besides at this point he won't be able to do his full PPL electric so he will still have a few hours on a gas engine for cross countries.

I agree sourcing a off the shelf car motor is not the most efficient usage they are indeed heavy thought overall when you add everything together motor + controller + batteries!! the price tends to go up fast. almost 40% due to battery cost.

Luckily technology keeps improving and as time goes on it will continue the current trend of technology improvements.

BTW battery controller can easily read battery capacity the issue is how can a pilot relay information to ATC (more than transponder code).
I don't think the FAA has gotten that far with technology.
Regardless you could still do something for the student that wants to take-off without full batteries.

Supposedly his farther along this time and has been in talks with the FAA where they appear to be working on writing a exception/different rules for electric.
But yeah current Regulations are tailored a lot to gas engines.
That Part 23 rewrite cannot get here any faster.
Yeah a custom build airframe would go a long way on this point, maybe battery improvements by the time something like this can be sold/done would allow for more payload increase.

Yup China has a serious pollution problem and they started to work on it fast. I mean when you wake up in the morning and you can barely see 30 feet in front of you because of how bad the smog is.
It definitely reminds you that this is a problem to fix today and not in 50 years.

Any specific reason why you chose deep discharge batteries?
I would definitely not bother calculating the weight with those.

17. Jul 27, 2016

### gtae07

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That's incorrect. I have multiple 50A/240V circuits in my house and workshop and I do not have three-phase power. I can't run all of them at the same time since my main panel is limited to 200A maximum. My workshop is fed with a 90A breaker off the main panel. You see 240V circuits in the US all the time for electric dryers, stoves, HVAC, welders, etc. You just use an appropriate breaker (which spans two regular 120V connections) and wire it appropriately.

18. Jul 27, 2016

### Manticore

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Any battery which is being used in a full charge/discharge cycle - whether it's Lead Acid, Lithium or whatever - needs to be technically a deep discharge battery otherwise it's not going to last very long.

19. Jul 27, 2016

### Pops

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Sounds good except no cross country flights and the cost per hour for equipment would be very high. Maybe practical some day, but we are a long ways from it now.

20. Jul 27, 2016

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