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All-electric trainer aircraft, cheaper than Cessna

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Re: All-electric trainer aircraft, cheaper than Cessna

#51

Post by sokoloff »

coredog64 wrote: post #32
ams6110 wrote: post #10

An electric powerplant with effectively one moving part should also have dramatically lower mantenence cost than a traditional, gasoline-powered engine of more than 1,000 components I see this sort of statement made about electric cars also, and I think it's really not true. Modern internal combustion engines are very reliable, and need very little maintenance. Yes they need oil changes every so often, and I guess th…

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.

Absent a propeller strike, a teardown inspection is almost never indicated between overhauls. Yes, the airframe and engine get inspected annually, but the engine is not "torn down" during those inspections.

Re: All-electric trainer aircraft, cheaper than Cessna

#52

Post by sokoloff »

djrogers wrote: post #45
CPLX wrote: post #23

Earlier quoted context omitted.

> 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...

All the bizjets, King Airs, PC12s, TBMs, and Caravans are turbine (and most are GA). Plenty of turbines in GA and they fly a lot of hours. (It's not the majority of airplanes, but it probably is the majority of hours flown.)

Re: All-electric trainer aircraft, cheaper than Cessna

#53

Post by sokoloff »

sgnelson wrote: post #27
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.

Serious question from someone who knows very little about planes. Do they seriously still have new carbuereuted planes? I can understand if it's a Cessna from the 50's, 60's, 70's, but I'm surprised they haven't been converted to EFI just from an efficiency and reliability stand point. Does that have to do with all the certification required for aircraft? (ie, if you change the engine, the aircraft has to go through…

Most of the injection systems on piston aircraft are mechanical injection, not EFI, for reliability reasons. EFI with closed-loop lambda control for street cars makes sense because of the widely varied load that a street car has to do and the need to keep the mixture in a close range to keep the catalytic convertor working well under these varied conditions.

An airplane engine has a far more steady-state load condition. As a result, fixed ignition timing and mechanical fuel injection with manual mixture control is "good enough" and very simple/reliable. Likewise for carbs and carb heat on the O- engines. It works and works very well.

There is a process for modifying certified aircraft. STC (Supplemental Type Certificate) is the primary means for changing engine configuration. It's some amount of work, but isn't prohibitive. (I have STC'd modifications on every airplane I've ever owned. It's not that big of a deal, if your modification has sound engineering basis.)

Converting from a carb to fuel injection is possible, but many of those conversions involve installing a fuel header tank that the airframe didn't originally have. Sometimes this changes the fuel system for the worse (eliminating the "both" tank setting) and/or puts a header tank in a place to spray pressurized fuel into the cabin in the event of a forced landing. I looked into converting my 182 to an IO-550 (from an O-470) and that was unappealing to me. Instead, I upgraded to an O-520 (still carb'd, but larger displacement).

Re: All-electric trainer aircraft, cheaper than Cessna

#54

Post by comicjk »

dmd wrote: post #11
DrScump wrote: post #5

It seems like an obvious feature would be to have solar cells on the upper wing surfaces... I guess the energy payout isn't sufficient for the area?

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

To be more serious, a Cessna 152 has an 82 kW engine and a wing area of 14.9 m^2. On a sunny day (1 kW/m^2) with 20% efficient panels and a 90% efficient motor, the solar panels would supply 3.2% of that power. So it's not possible to build a solar plane this way, but it's not 0.01% either.

https://en.m.wikipedia.org/wiki/Cessna_152

Re: All-electric trainer aircraft, cheaper than Cessna

#55

Post by walrus01 »

AdrianB1 wrote: post #42
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.

You can't buy a modern Pipistrel for th price of a 1975 Cessna. A huge % of the light 2 and 4 seat aircraft out there in the c172 and smaller sizes are 25+ years old.

Re: All-electric trainer aircraft, cheaper than Cessna

#56

Post by Zombieball »

wp1 wrote: post #6
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.

I would gladly pay for 5 hours of training for a combustion endorsement, if I could avoid fuel costs for 40+ hours of training to get my private certificate.

This is a good point and kind of along the lines of what I was thinking. A fuel endorsement might be what's needed.

Re: All-electric trainer aircraft, cheaper than Cessna

#57

Post by Zombieball »

sokoloff wrote: post #18
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.

Should be no issue. Most people get transition training when starting to fly a new type. Carb vs fuel injection, normally aspirated vs turbo-normalized vs turbo-charged, use of flaps for max performance takeoffs, etc are all minor (but important) differences. Minor nit: high performance is an endorsement, not a rating. (It's a CFI sign-off, not a checkride.)

Good call out RE: endorsement vs. rating. The proper naming was alluding me (still only a student pilot, ~40hrs, myself as a hobby).

Re: All-electric trainer aircraft, cheaper than Cessna

#58

Post by Zombieball »

AdrianB1 wrote: post #26
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.

In 2016 having a fuel mixture in a plane makes me wonder why is that needed; not only that some popular engines (like Rotax 912 family) do not need it, but processor controlled injection engines definitely do not need it. Fuel mixture is so 1960 and carb heat so 1990... (I'm a pilot in my free time flying propeller driven 2 seaters).

I don't know about you, but I'm definitely not flying planes made in 2016, let alone this millennia!

Re: All-electric trainer aircraft, cheaper than Cessna

#59

Post by dingaling »

sgnelson wrote: post #27
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.

Serious question from someone who knows very little about planes. Do they seriously still have new carbuereuted planes? I can understand if it's a Cessna from the 50's, 60's, 70's, but I'm surprised they haven't been converted to EFI just from an efficiency and reliability stand point. Does that have to do with all the certification required for aircraft? (ie, if you change the engine, the aircraft has to go through…

> Do they seriously still have new carbuereuted planes?

Yes, and for example you can choose your new-from-the-factory Robinson R44 helicopter with either carb ( Raven I ) or injection ( II ). The former has slightly lower fuel consumption and longer engine life, the latter better performance.

Re: All-electric trainer aircraft, cheaper than Cessna

#60

Post by slavak »

sgnelson wrote: post #31

my next question is: When will we have these small planes with true autopilots, which would allow a true novice to fly them? And surely people are working on them, but you don't hear about that as much as you do automobiles. Anyone know anything about this?

Probably not in the foreseeable future; the market just isn't there, and in large part- the technology isn't either.

For one thing, the technology for truly automatic or nearly-automatic landing (takeoff might be simpler) requires a lot of equipment at the airport, which the vast majority of airports a hobby pilot would fly from will never install. Since takeoff and landing are by far the most difficult and dangerous parts of the flight, this pretty much automatically precludes the possibility of an untrained pilot.

Add to that, the stance in aviation is that the pilot must be capable of taking control of the aircraft if there is any problem with the automation. I don't know the statistics, but presumably the sensors and automation by itself are not reliable enough to function completely autonomously and without supervision 100% of the time. And if you're gonna have a hobby pilot that is perfectly capable of flying the plane manually, full automation is just a massive waste of money.

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