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BoKu

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At the very best, that's a wild stretch of a claim. Aircraft have been flying with ICE engines for over 100 years. Vibration hasn't been the issue that you're claiming. Like, at all. Let's keep the discussion within the bounds of reality, please...
The reality is that noise and vibration of the kind you experience in a typical small airplane is a huge driver of fatigue and discomfort, and there is a huge body of human factors data to show that it almost certainly affects training. The only reason we don't know how much is that until now there hasn't been much to compare it with except gliders, and the context is so different it's hard to get much out of that comparison.
 

BJC

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The reality is that noise and vibration of the kind you experience in a typical small airplane is a huge driver of fatigue and discomfort, and there is a huge body of human factors data to show that it almost certainly affects training. The only reason we don't know how much is that until now there hasn't been much to compare it with except gliders, and the context is so different it's hard to get much out of that comparison.
Agree.

There is a significant difference in vibration and comfort level between my airplane and the all aluminum brand RV’s. Add a quality noise cancelling headset that is light and doesn’t squeeze one’s head or drive glasses frames into one’s temples and the fatigue after flying for 6 to 8 hours is very noticeably less. Electric should be even better.


BJC
 

tspear

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@Vigilant1
@Topaz

My comment about vibration was in context of @bmcj who stated the fire danger due to wires chafing and other issues are the same between electric and ICE. I was disagreeing, engine vibration in an ICE is significantly worse. And it is this vibration that causes chafing and many other related issues. These risks are not the same, or even close to being the same.

@Topaz
Actually, there are a number of people in this thread who state electric planes should not be done. And further, they set impossible standards for electric planes to be met.

Tim
 

tspear

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In this era, by far the single largest issue for a flight school, and flight training overall, is now the cost. The cost controls how often you take a flying lesson, it controls how long it takes you to get your ticket, it controls the real-world level of safety/maintenance that the school can provide, and most importantly it controls the quality and depth of the education you get.

So (assuming that the airplanes fly roughly the same) any new technology or new operational model will ultimately be measured by how much more or less it costs the consumer, and the school, to use it.

If electric airplanes are able to lower the cost of flight instruction for the customer and the school, then it's a glorious winner for that alone.

If, after all the math is done and all the pennies are added up, electric airplanes result in higher cost of flight instruction... then it's a friggin' loser for that alone.

I'm no accountant, and I cannot predict whether the costs will actually be higher or lower when everything is considered.

It is possible that the electric stuff may be more expensive in the beginning and then much much more cost-effective in the long run. It also may not be.

But I believe very strongly that all of the other factors, quieter cockpit, less vibration, coal-fired powerplants, laminar airfoils, technology-loving Millennials, smiling "green" Save the Planet bumper stickers... and everything else... doesn't amount to a cockroach turd compared to the actual near-term cost savings or cost increase of this new school model.

I think we really ought to support it as a demonstration and testing exercise, with the primary focus of proving out whether it does, will, or can lower the cost of flight instruction.
I agree. I think battery tech needs to advance another 25-30% to get to the point where you do not push the battery to design limits on every flight and can therefore extend the battery life for simple training. This is only three to four years away; so having early adopter planes now and starting to build operational experience is a good thing.
Until that level of battery tech is achieved, I expect electric planes to cost more on a per hour basis. However, the upgrade cost to replace the battery pack with higher energy density / lighter and make the plane more useful is much cheaper than upgrading an ICE plane. This bodes well for future upgrades on these early adopter planes.

Tim
 

BJC

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These risks are not the same, or even close to being the same.
There is a difference; ICE powered E-AB typically have 12 volt systems. Electric powered planes likely will operate at much higher voltages, so the potential risks / problems will be different.

With either power source, proper material selection and installation is the key to reliability.


BJC
 

Dan Thomas

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The reality is that noise and vibration of the kind you experience in a typical small airplane is a huge driver of fatigue and discomfort, and there is a huge body of human factors data to show that it almost certainly affects training. The only reason we don't know how much is that until now there hasn't been much to compare it with except gliders, and the context is so different it's hard to get much out of that comparison.
Even in a turboprop there's plenty of vibration. If that prop isn't perfectly balanced, it shakes the airplane. The assymetric thrust created by a propeller in the climb (AoA on downgoing blade is larger) creates vibration. The pulse of air off each blade hammers at the windshield and wing leading edges and the tail. The shock wave off the prop tips affects the airplane to some degree, worse in a twin.

The electric won't be vibration-free, but it will be better and there won't be any exhaust noise to pound on the belly or anywhere else. It will never be as smooth as an IC automobile, though. Not when we're dealing with propellers. In many IC airplanes the prop noise outweighs the exhaust noise, too.
 

Dan Thomas

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In this era, by far the single largest issue for a flight school, and flight training overall, is now the cost. The cost controls how often you take a flying lesson, it controls how long it takes you to get your ticket, it controls the real-world level of safety/maintenance that the school can provide, and most importantly it controls the quality and depth of the education you get.

So (assuming that the airplanes fly roughly the same) any new technology or new operational model will ultimately be measured by how much more or less it costs the consumer, and the school, to use it.

If electric airplanes are able to lower the cost of flight instruction for the customer and the school, then it's a glorious winner for that alone.

If, after all the math is done and all the pennies are added up, electric airplanes result in higher cost of flight instruction... then it's a friggin' loser for that alone.

I'm no accountant, and I cannot predict whether the costs will actually be higher or lower when everything is considered.

It is possible that the electric stuff may be more expensive in the beginning and then much much more cost-effective in the long run. It also may not be.

But I believe very strongly that all of the other factors, quieter cockpit, less vibration, coal-fired powerplants, laminar airfoils, technology-loving Millennials, smiling "green" Save the Planet bumper stickers... and everything else... doesn't amount to a cockroach turd compared to the actual near-term cost savings or cost increase of this new school model.

I think we really ought to support it as a demonstration and testing exercise, with the primary focus of proving out whether it does, will, or can lower the cost of flight instruction.
Might need an electric-only license for those that learn on electrics. Similar to the automatic transmission-only driver's licenses some folks got when I was a young feller, if they didn't learn in a manual.

Plenty of students learn on a 150 or 172 and fall in love with that airplane and go buy one. They haven't the experience to know that there are other, often better, airplanes. The one who gets an electric PPL will go buy an electric airplane. If he can afford it. Or the school will cynically sell him one of theirs in which the battery pack is just about dead. Lots of naive people buy beat-up flight school airplanes and end up broke.
 

Vigilant1

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....
I'm no accountant, and I cannot predict whether the costs will actually be higher or lower when everything is considered.

It is possible that the electric stuff may be more expensive in the beginning and then much much more cost-effective in the long run. It also may not be.
....
I think we really ought to support it as a demonstration and testing exercise, with the primary focus of proving out whether it does, will, or can lower the cost of flight instruction.
It sounds like you are suggesting an operational test and evaluation (OT&E) for these electric planes in flight school use. If Pipistrel hasn't done one already, then a well documented one would be worth a lot to them as a marketing tool.
Assuming their battery management system is smart enough to log the use and charging pattern of each pack, they'll have enough info to know if the batteries are being used according to whatever standards they set.
If I owned a flight school and Pipistrel was promising that costs would be low, I'd ask them to back it up in the way that counts--money. I'd follow their required charging/discharging protocol and get a 10 year contract for a fixed (or CPI linked) cost per hour. I'll buy the electricity, they pay for all parts (battery replacements, motor rewinds, etc). Or, I'll offer to lease the planes from them at some price per flight hour and a guaranteed min number of hours per year. There are a million other ways to structure it--Pipistrel could take a share of what is saved over the use of IC engines, etc.
Pipistrel knows much more about the costs of this novel propulsion system than anybody else , it's reasonable to ask them to share some risk here. They'll get a lot of data and a ready-to-go model they can roll out at other flight schools/clubs/fleet operators if it's such a great way to reduce flight cost per hour. The fact that they are apparently not doing this already may tell us a lot.
To ask taxpayers to foot the bill/take the risk for Pipistrel ain't right, IMO. That's not directly related to this proposal to the FAA.
 
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Topaz

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The reality is that noise and vibration of the kind you experience in a typical small airplane is a huge driver of fatigue and discomfort, and there is a huge body of human factors data to show that it almost certainly affects training. The only reason we don't know how much is that until now there hasn't been much to compare it with except gliders, and the context is so different it's hard to get much out of that comparison.
Having received flight instruction in both types (ASEL and Glider), I've never seen the noise and vibration of the former to have been an issue in my own flight training. Further, I've yet to see a post here on HBA, or heard a report in real life, to the effect that "noise and/or vibration interfered with my training."

I will gladly concede that the (relative lack of) noise and vibration in an electric-powered aircraft is better. But let's please not, in the service of supporting electric aircraft, suddenly claim that there's a "problem" with training in ICE aircraft that hasn't actually existed. Might the past 100 years of student pilots learned with some reduced measure of fatigue if they'd been trained in electric aircraft? Perhaps. Did they seemingly learn just fine in ICE-powered aircraft despite this "handicap"? Yes, they did.
 

BJC

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Can I cite a study that supports BoKu’s contention? No.

Do I believe that the “learning environment” could be better in an electrically powered aircraft? Yes.

I believe that, even in a relatively quiet combustion engine airplane, the learning environment is enhanced by the use of a quality noise cancelling headset.


BJC
 

Topaz

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... Do I believe that the “learning environment” could be better in an electrically powered aircraft? Yes.
I don't think anyone disputes that. Certainly I don't. But that's not the question at hand. Anything can be improved. But the past 100 years of flight training seem to indicate that flight training in ICE-powered aircraft is adequate to the task, and so I'm saying "noise and vibration" isn't an issue that can be counted as a "strike against" ICE-powered training aircraft, as is being done here, IMHO.

In electric car conversations, I sometime see people say that EV's are better than ICE-powered cars, "because gasoline is horrifically flammable and dangerous for ordinary people to handle for fueling." That's a bad argument in favor of EV's. On the face, and out of context, it's nominally "true," but in actual practice, the infrastructure that's developed makes the risk virtually non-existent in real life.

I'm saying that "noise and vibration" hasn't been any significant impediment to flight training in ICE-powered aircraft, in actual practice, so that is a bad argument against them, and therefore not a good argument in favor of electric-powered trainers. On it's face, and out of context, the statement is nominally true that less noise and vibration makes for a better learning environment, but that's not really relevant because ICE-powered aircraft have been shown to be perfectly adequate to the task. Doesn't mean I'm against electric-powered aircraft or "progress."
 

Vigilant1

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The school in Fresno does have a Pipistrel Alpha with a Rotax 912. I'm guessing that"s what they'll use.
The planes with the batteries have different weights and thrust from the gasoline models. I would think changing planes might be less than optimum for the continuity of a low time student. It will be interesting to see which airplane the students prefer. Lower cost, better climb, faster cruise, longer range, or ... less vibration, lower emissions.

OR, the same guy plans to go back to the FAA for another request for special dispensation. Hey, if it worked once...
 
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