What would early 1900s aeroplanes sound like if they were powered by electric engines ?

[Petike]

Early ICE aero engines ran without reduction gears, as they were low RPM, and had enough useful torque to spin the prop.
Electric motors tend run at higher RPMs, and high RPMs get you into that supersonic tip speed.
Bakers used chain drive for their reduction, and only 3.5HP, with 6 HP overload for around 10 minutes at 150 amps
You won't be getting off the ground with that low of HP, unless you have zero weight batteries

That is certainly true, and that's exactly why I expect the engines to be clearly louder, while still significantly quieter than an aeroplane ICE.

In my scenario, for my fictional setting, I do have the added advantage of the batteries being much lighter. You can't bet on the electric engines having RPMs that high. I don't think they'll be hitting supersonic speeds with the propeller tips, unless they realy rev up. You can't compare the engines of the time with the present day ones. The former will have lower RPM than a contemporary, highly efficient version.

A soft buzzing from the electric engine but propellers were not that efficient in the 1900s so there would be the characteristic chop chop sound of the propeller inefficiently moving through the air

Well, obviously. It's a propeller aeroplane, either traction or pusher configuration, so there's no chance of it being nearly silent.

 

[marathag]

. You can't compare the engines of the time with the present day ones. The former will have lower RPM than a contemporary, highly efficient version.

a direct drive, 1950s 100HP O-200 with a 71" prop running at 2700 will get you supersonic tips, while the engine overspeed limit was 3000rpm for stock, tuned for race it could hit 4000.
You would want the geared version for that high RPM operation

 

[Petike]

a direct drive, 1950s 100HP O-200 with a 71" prop running at 2700 will get you supersonic tips, while the engine overspeed limit was 3000rpm for stock, tuned for race it could hit 4000.
You would want the geared version for that high RPM operation

Yes, but what would an early 1910s equivalent of that be ?

 

[AJE]

Do you think we can get these airborne with pre-1920s tech ? Even if the chemicals in the batteries will have to be somewhat ASB in terms of life and propulsion performance, as I've mentioned earlier in this discussion ? (For the sake of argument, let's accept the batteries issue has been cracked and they're up to snuff, even if it is a tiny bit ASB.)

With the batteries, yes- the motors should have been as powerful or slightly more powerful than piston engines of the same weight, for any given era. So that should be able to fly if the batteries can be solved.

Petrol engines need more moving parts, both in cars and in planes, and in all other motorised vehicles. That's a simple fact. If you're going to use a liquid fuel combustion engine, you need more moving parts in an engine, more gears, more mechanical complexity, in order for the engine to work at all. Internal combustion, with its very carefully managed mini-explosions serving as motive power, require that, whether we like it or not.

It's telling that both historical and contemporary electrical cars have, as far as I know, never needed transmission. Or only token versions of it, similar to a watered-down automatic transmission or transmissions on an ordinary mountain bike. Whereas in a petrol car in particular, you have to shift gears at certain speeds, and you have no choice in the matter, in an electric one, you don't bother with gear shifting at all.

When shifting, yes it would cause more noise. But in normal operation a car gearbox only uses 2 gears at any given time (depending on the gearbox):

An electric motor will also use 2 gears at all times (if it is the same 2 gears):

So the gears themselves should produce the same amount of noise outside of gear switching, as most are disconnected in a multiple-speed transmission and aircraft reduction gears are usually single-speed anyway.

Yes, the early 20th century wasn't the 1800s anymore, they figured out that crudely manufactured parts are not conductive to performance.

If these parts were so catastrophically inefficient for decades, I think a lot of vehicle manufacturers would have long gone out of business.

Technically they would still be deafeningly loud at turbine speeds until 1912 (even <1% of the power is enough to do that), but if you're looking after 1912, then that should be fixed.

Yes, but what would an early 1910s equivalent of that be ?

In the early 1910's, nothing. From 1915, the demands for more power at all costs in WWI would result in the Rolls-Royce Falcon's epicyclic reduction gear, allowing higher speeds (and power) at the cost of reliability. After 1917 the Hispano-Suiza 8b was available with a reduction gear, and had such bad reliability that at times 50% of all engines were out of service, and the Napier Lion also had one from its introduction in 1918 until the mid 1920's when it was abandoned due to unreliability.

 

[CalBear]

They would sound like a plane crash.

Too little power for the weight of the batteries. Battery life would be too short even if the aircraft could get enough lift.

Tech isn't there.

 

[marathag]

Yes, but what would an early 1910s equivalent of that be ?

The Curtiss Model K engine, an inline four rather than a boxer like the Continental, and liquid cooled rather than aircooled.
It did 40 HP at 1500 rpm from it's 251 cubic inches.
The O-200 is an outgrown of the early 1930s Continental A40, that was 40 hp at 2500 rpm with dual ignition, despite being only 115 cubic inches.
More compression, more rpms. A lot of vibration limits from better understanding of dynamic balancing were overcome in the 1920s

 

[marathag]

So the gears themselves should produce the same amount of noise outside of gear switching, as most are disconnected in a multiple-speed transmission and aircraft reduction gears are usually single-speed anyway.

here is what true 'noisy' replacement timing gear set rather than the silent chain drive

https://www.summitracing.com/parts/pqx-0135001/make/chevrolet

Performance Quotient PQx Dual Gear timing sets eliminate the stretching and premature wear common with timing chains. These dual idler gear drives fit under most timing chain covers with little to no machining, and offer more stability than single gear drives. The steel alloy gears provide longevity, and are available in noisy or quiet versions for most applications

 

[Petike]

They would sound like a plane crash.

If the batteries are insufficient, then yes, not even a good engine would be of much help and a plane would crash.

Or perhaps not crash, but not take off much, and be forced to glide down back almost immediately.

Too little power for the weight of the batteries. Battery life would be too short even if the aircraft could get enough lift. Tech isn't there.

I agree you with you, if we're being strict, but please note: Already at the beginning of the discussion, I noted the obvious problem with the batteries and encouraged people in this discussion to imagine we have powerful enough batteries in that period. (Yes, admittedly a bit ASB, as I myself mention repeatedly, but just for the sake of this as a thought experiment - as noted in one of the tags - let's assume the batteries are not an issue or less of an issue.)

I don't think it's true to say the tech isn't there. It is, the engines are already pretty efficient - otherwise you wouldn't have successful electric engine powered blimps already in the late 19th century - but not all of the tech has matured yet to make this readily viable, on an everyday basis. Particularly the battery tech.

Neither me nor AJE are suggesting that electric planes were just around the corner in the first two decades of the 20th century, but we're pondering if they would be possible with a few "unobtainium" tech issues sorted. So, not necessarily possible in a full-on rigorously realistic timeline, but perhaps more viable in a timeline where at least the power source issues are dealt with via some fictional, mildly ASB aspect (e.g. stronger batteries utilising some fictional form of electrolyte that lasts far longer and gives far greater performance).

The Curtiss Model K engine, an inline four rather than a boxer like the Continental, and liquid cooled rather than aircooled. It did 40 HP at 1500 rpm from it's 251 cubic inches. The O-200 is an outgrown of the early 1930s Continental A40, that was 40 hp at 2500 rpm with dual ignition, despite being only 115 cubic inches. More compression, more rpms. A lot of vibration limits from better understanding of dynamic balancing were overcome in the 1920s

Thank you !

Were there any smaller air-cooled electric engines of the 1910s we could compare it with ?

here is what true 'noisy' replacement timing gear set rather than the silent chain drive

https://www.summitracing.com/parts/pqx-0135001/make/chevrolet

Performance Quotient PQx Dual Gear timing sets eliminate the stretching and premature wear common with timing chains. These dual idler gear drives fit under most timing chain covers with little to no machining, and offer more stability than single gear drives. The steel alloy gears provide longevity, and are available in noisy or quiet versions for most applications

That's all well and good, but that's still a petrol engine. If we want a proper comparison, we should take an electric engine of the period - ideally one that does not use a chain drive to propel a vehicle or some other device - and compare it with the drive structure of 1910s and early 1920s petrol engines (including this puppy). I'm under no illussion that an electric engine used in cars like the Baker Electric or Detroit Electric is going to have the same sort of output as you'd need for an early aeroplane. That's not feasible, so whatever electric engine we think of will obviously have to be buffer in performance.