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All-electric trainer aircraft, cheaper than Cessna

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Re: All-electric trainer aircraft, cheaper than Cessna

#41

Post by AdrianB1 »

pingec wrote: post #8

What about this one: http://www.pipistrel.si/news/wattsup-the-new-2seat-electric-... Not an expert - don't know if they can be compared and the article lacks any actual specs to compare by, but the pipistrel's electric plane seems to be much cheaper. "Pipistrel expects to bring the final product to the market in 2015 with a target price below 100,000 EUR."

50% of the cost of a plane sold in USA is put aside as reserves for litigations; that doubles the actual cost of the plane, so the Pipistrel that is sold in Europe for 100,000 EUR may be $220,000 in USA. The Cessna 172 is 300k; a modern Pipistrel with better flying capabilities is 100K (there are a couple of 2015 Pipistrel planes on my base airport). Cessna does not sell lots of 172's, but neither Pipistrel does not sell in USA at 100k. The aviation in USA is mostly based on cheap old 1950-1970 planes, the cost for new is astronomical.

Re: All-electric trainer aircraft, cheaper than Cessna

#42

Post by AdrianB1 »

yompers888 wrote: post #4

As someone who really would love to get into general aviation but finds the fuel costs off-putting, I'd love for this to be successful. Isn't the big problem with electric planes supposed to be the energy density per kg? Wikipedia is showing 46MJ/kg for jet fuel, vs only ~1MJ/kg for lithium batteries [1]. Is this a lesser concern than I've been led to believe, is there recent development that improves lithium batteri…

Cessna takes about 8 gallons per hour to fly; if you want to fly at 3 gallons per hour then go for any Rotax 912ULS plane, most are LSA but you can upgrade the license to PPL adn the flight time on LSA (cheap) is considered for PPL. In the end a Comko Ikarus C42 has similar performance with a Cessna 152 and a Pipistrel Virus SW is lighter and much faster (+30%) than the 152 for less than half the fuel consumption.

Re: All-electric trainer aircraft, cheaper than Cessna

#43

Post by highd »

mdorazio wrote: post #2

Does anyone have more specifics about the actual capabilities of the prototype? I'm skeptical they're able to get 3 hours of flight time out of a battery pack without sacrificing just about all the weight capacity for things like... a pilot. It's great to see that companies are actively working on electric-powered flight, though, especially in the small aircraft space where it has high potential. Also a small beef wi…

It's not stated very directly, but it appears the article is referring to hybrid propulsion systems much like in hybrid cars. That certainly makes sense for reducing fuel costs, as well as reducing the volume of fuel you'd need, thus reducing weight as well.

Re: All-electric trainer aircraft, cheaper than Cessna

#45

Post by djrogers »

CPLX wrote: post #23
Zombieball wrote: post #3

My concern about training on an aircraft of this fashion is that you get no exposure to controls such as carb heat, fuel mixture, etc. I wonder if a distinction will be made (in the not so far future) between getting rated on a combustion plane vs. electric? Much like you get rated for high-performance or twin engines today.

> no exposure to controls such as carb heat, fuel mixture, etc. Right. None of which are relevant to turbine aircraft anyways, which is the majority of all planes in the sky. It's relevant sure but the big things you learn in flight training are how to figure out where in the sky you are and should be, lift/drag stick and rudder stuff, and endless amounts of regulations. The means of propulsion is important sure but…

> Right. None of which are relevant to turbine aircraft anyways, which is the majority of all planes in the sky.

You won't find a lot of turbines in general aviation...

Re: All-electric trainer aircraft, cheaper than Cessna

#46

Post by cpncrunch »

AdrianB1 wrote: post #30

The big problem with the small planes is not the engine and fuel (still can't beat AVGAS in term of efficiency), but price; any part that exists in the automotive industry gets a 3 time price increase if it is used in aviation, 5 times if it is certified. A 1.4 liter 4 cylinder engine with 100 HP, that would be maybe 15-2000$ in a car, is ... 17.000$ for a small plane. A mobile radio for aviation starts from $300, a…

The FAA's Part 23 rewrite should help this. Just this month Dynon managed to get their D10A EFIS STC'd even though it isn't TSOd. Basically we will be allowed to put avionics designed for the experimental/homebuilt market into certified aircraft, resulting in a huge cost saving.

Re: All-electric trainer aircraft, cheaper than Cessna

#47

Post by djrogers »

sgnelson wrote: post #21
dmd wrote: post #11

Earlier quoted context omitted.

That might be sufficient to power half of the avionics (i.e., maybe 0.01% of the power consumption. )

I can't say anything to the power efficiency of solar cells, but I can see how they could be useful for when you're not flying. "Free" energy for when you're ready to fly if you don't fly the plan daily, but instead just fly on the weekends or such. In the middle of nowhere without fuel or electric hookup? Wait a few days and at leas the plane will have energy to fly out of there. I'm not saying that will be the case…

You'd be much better off to simply have a few panels on a rack that you put out next to the plane. Being forced to haul around the extra weight of the panels on the top of the wings would be counterproductive, and if you really wanted the panels with you one day, you could pack them up and take them with you.

Re: All-electric trainer aircraft, cheaper than Cessna

#48

Post by cpncrunch »

yompers888 wrote: post #4

As someone who really would love to get into general aviation but finds the fuel costs off-putting, I'd love for this to be successful. Isn't the big problem with electric planes supposed to be the energy density per kg? Wikipedia is showing 46MJ/kg for jet fuel, vs only ~1MJ/kg for lithium batteries [1]. Is this a lesser concern than I've been led to believe, is there recent development that improves lithium batteri…

>As someone who really would love to get into general aviation but finds the fuel costs off-putting

I'm not sure why you think the fuel costs are off-putting. I fly a Cessna 150 which burn 5.5 gallons per hour. If you fill it with unleaded (which can be done with a $150 piece of paper), the fuel cost is less than $15/hr.

Re: All-electric trainer aircraft, cheaper than Cessna

#49

Post by sokoloff »

peteretep wrote: post #44

I was on a little Cessna Caravan twice this weekend, and both times was struck by how much less the torque on them is than a Tesla...

Early PT6-114s (the turboprop engine on the early 208s) have a takeoff torque limit of 1658ft-lbs. Later PT6-114As (the current engine on the 208s) has a takeoff torque limit of 1865ft-lbs.

The Tesla P85D has less than half of that.

The Caravan has much less initial acceleration than a Tesla, but far more torque.

Re: All-electric trainer aircraft, cheaper than Cessna

#50

Post by djrogers »

ams6110 wrote: post #36
coredog64 wrote: post #32

Earlier quoted context omitted.

GA engines require a teardown inspection on a pretty regular basis. Not only that, but the liability tail for GA emphasizes the use of older designs.

Presumably electric motors would require the same, then, in an aviation application?

The teardown and inspection of an electric motor is trivial compared to that of an internal combustion engine. Generally speaking, you'd undo a few fasteners, pop off a cover, and check/clean the rotor/windings. 15 minutes tops - heck, you could do it before every flight and it'd still be cheaper than paying for the 100-hour maintenance on a GA plane.
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