Are HYBRID helis the future of rotorcraft?

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henryk

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Mar 8, 2010
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5,155
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krakow,poland
Scaling up often yields poor results. You'll need lower disk loading or more electric motor....


(use less steel and plastic - use more aluminum
-we was preliminary tested 7m gyro rotor gearless drived by 20 kW electric motor
(154-120)...its a pity, at 10 kW (100 V, 100 A) some coils was burned !

now we have double 40 kW motors (202-120) +two 500 A controllers, ready for testing.

View attachment 78422 View attachment 78423
 

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henryk

Well-Known Member
Joined
Mar 8, 2010
Messages
5,155
Location
krakow,poland
Burn baby burn! Don't let that magic smoke escape those motors....... What's the weight of all that ?
motors+ controllers (rotating with main rotor)=circa 10 kg...

the all device is similar to ROTODYNE.

BTW=doubled motor my be replaced with one, 100 kW (right on the picture)
 

thjakits

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Joined
Jul 3, 2014
Messages
52
Location
Panama, Rep. of Panama
HYBRID Helicopters are not going anywhere.
The future is FULL-ELECTRIC...
You either trade the transmission for the generator/motor you need to drive the old rotor up there or you need to get rid of internal combustion all together and stack a load of batteries.
The different rotor/wing combinations don't change anything on the purpose and aerodynamics - just a different drive-train....

The only point where I could see a possible (and it is a VERY IF question....) benefit for a 2-5 min hybrid system is, when a helicopter comes down in essentially a autorotation and would ask for "negative rpm governing".
When you are in the mountains and cannot descend because of sever up-winds - one has to keep the MR in the green rpm range. One is essentially in autorotation and cannot lower the collective any further or risk to overspeed the MR.
In such a case it would be great to have something to be able to load the rotor else but with pitch angle....

Overall efficency would be very tightly tied to an optimized battery/generator/motor-weight balance...

To the Osprey: A LOT of the trouble with that bird resulted from the very complex (and therefor HEAVY) storage requirement - watch youtube for demos on folding and unfolding that rig!!

The 609 is still a highly stressed machine - you don't just flip those prop/rotors! There are huge precession forces at work!

Personally - as long as rotorcraft have to provide autorotation capability - I see the Airbus approach to combined abilities as the best approach - see
and
and
There are no inherently contra-acting forces at hand - all drive components always contribute to any flight configuration at hand - basically no waste of energy at any time....

On the homebuilt front - BJ Schramm did that already 25 years go!
(watch at 13:10)

Though BJ's machine didn't have a distinct wing section for flight....

As long as certified rotor lifted flight requires autorotation capability I don't see Helicopter/Gyro design deviate much from what you see today - the power/speed/lift capabilities are a fine-tuned comprimise considering autorotation.....

When autorotation capability can be abandoned (as it is done with multi-rotor drones - man carrying or not) things will of course change radically!

Any dreams of "magic" electric performance is just that - "magic" and that doesn't exist!
Electricmotors are capable of incredible power-output for VERY short times - seconds!! Then they melt!!
Not much different from piston engines and turbines - no magic there. After that, weight optimization is just about the same and so far petroleum based fuels are still the winner for range.

We are seeing the first serious tests of electric drive and they work beautifully - but we are still range/time limited.
when electric storage density matches ICE THEN we are in the game - it's coming and improving daily....

But the overall helicopter/gyro design - at least for commercial applications - won't change fundamentally until autorotation requirements cease to exist - no matter what and how you drive the rotor(s)....


Cheers,
thjakits
 

Doggzilla

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HBA Supporter
Joined
Jun 2, 2013
Messages
2,263
Location
Everywhere USA
HYBRID Helicopters are not going anywhere.
The future is FULL-ELECTRIC...
You either trade the transmission for the generator/motor you need to drive the old rotor up there or you need to get rid of internal combustion all together and stack a load of batteries.
The different rotor/wing combinations don't change anything on the purpose and aerodynamics - just a different drive-train....

The only point where I could see a possible (and it is a VERY IF question....) benefit for a 2-5 min hybrid system is, when a helicopter comes down in essentially a autorotation and would ask for "negative rpm governing".
When you are in the mountains and cannot descend because of sever up-winds - one has to keep the MR in the green rpm range. One is essentially in autorotation and cannot lower the collective any further or risk to overspeed the MR.
In such a case it would be great to have something to be able to load the rotor else but with pitch angle....

Overall efficency would be very tightly tied to an optimized battery/generator/motor-weight balance...

To the Osprey: A LOT of the trouble with that bird resulted from the very complex (and therefor HEAVY) storage requirement - watch youtube for demos on folding and unfolding that rig!!

The 609 is still a highly stressed machine - you don't just flip those prop/rotors! There are huge precession forces at work!

Personally - as long as rotorcraft have to provide autorotation capability - I see the Airbus approach to combined abilities as the best approach - see
and
and
There are no inherently contra-acting forces at hand - all drive components always contribute to any flight configuration at hand - basically no waste of energy at any time....

On the homebuilt front - BJ Schramm did that already 25 years go!
(watch at 13:10)

Though BJ's machine didn't have a distinct wing section for flight....

As long as certified rotor lifted flight requires autorotation capability I don't see Helicopter/Gyro design deviate much from what you see today - the power/speed/lift capabilities are a fine-tuned comprimise considering autorotation.....

When autorotation capability can be abandoned (as it is done with multi-rotor drones - man carrying or not) things will of course change radically!

Any dreams of "magic" electric performance is just that - "magic" and that doesn't exist!
Electricmotors are capable of incredible power-output for VERY short times - seconds!! Then they melt!!
Not much different from piston engines and turbines - no magic there. After that, weight optimization is just about the same and so far petroleum based fuels are still the winner for range.

We are seeing the first serious tests of electric drive and they work beautifully - but we are still range/time limited.
when electric storage density matches ICE THEN we are in the game - it's coming and improving daily....

But the overall helicopter/gyro design - at least for commercial applications - won't change fundamentally until autorotation requirements cease to exist - no matter what and how you drive the rotor(s)....


Cheers,
thjakits
You do realize that 1000hp+ electric cars are a thing, and that there are hybrid F1 cars that greatly outperform standard F1 cars, correct?
 

thjakits

Well-Known Member
Joined
Jul 3, 2014
Messages
52
Location
Panama, Rep. of Panama
"You do realize that 1000hp+ electric cars are a thing, and that there are hybrid F1 cars that greatly outperform standard F1 cars, correct?"

Yes I do! And I love it!

You also need to realize that you CANNOT translate applications at random.
There is nearly NOTHING from a F1-car you can apply directly to a road car. The most innovation you get from F1 tech is that - innovation/research - usually resutling in completely different applications on the road.
Racing is NOT daily-driver-Grocerygetter or even Sportscar-driving....

Hybrid in Racing is not really about "economizing" it is about "politics and acceleration".
Hybrid on the road is - essentially - about lowering your fuel consumption by recovering braking-energy.
For that you need MASSIVE generators/motors. Some may think Telsa and co are putting 600 hp into the Model 3 to win 1/4 miles. How many compacts do you see or even could purchase that have 600hp? That's "Special Edition"-Corvette territory! Why would a small 4-door sedan need that?
Well - you can take your time to accelerate to 65 mph (let's say with a 130hp engine) - but when you need to stomp on the brakes to get to a dead stop in a hurry - you won't have the same time to slow down - you need to slow down at the max adhesion you can get from the tires (ABS!) and so far that energy goes into friction produced heat at yout brakes!
Now to "harvest" (re-gen braking) that energy you need to be able to transform that kinetic energy FAST into electric energy - to do this fast you need a BIG generator, transformer/controller and a battery pack that can take a very high current load on charging - at least for the time it takes to stop.
For a hybrid that's really all the calculation you need/want - it's a balance of expense and weight - you want to accomodate 1 or 2 or 3 or xx number of max weight, max downhill grade full stop brakings from xx speed in xx number of seconds or minutes.
According to that you size the equipment.
So - you have now a 600 hp generator, because that's what you need to stop your chosen number of times without melting the **** thing! Just so happens that the generator becomes the motor if you push eletricity into it!!
NO sane manufacturer will say you can generate 600 hp to brake but I won't let you use more than 130 hp to play!
THAT's why you get "outragious" hybrids and electric cars! [Granted, some Supersport-cars HAVE to be hybrid these days because otherwise they can't keep up with a certain 7-seat, 4-door electric sedan...]
Now - be aware, even Tesla cannot stay in "ludicrous" mode indefinitely. The extreme fun is there really just for a minute or so, then they have to dial back quite agressively or something will melt.... [A bit like a lightning rod - it can take a lightning bolt, but if that bolt would hold up for a few seconds longer the rod WILL evaporate!]

The idea for a electric car is NOT the same as a hybrid - hybrid is way more complex as it has to deal with a ICE-power train and incorporate a electric system too - typical parallel-hybrid.
Electric is simpler as it is only ONE system. The balance between battery/motor-generator/controller weight is mostly about the same - ICE, trans/clutch/fuel-tank taking away from the possible battery weight....

Hybrid is still great where you do not have proper charging capacity available...

You also could rig a ICE-generator to bring along in the Electric. IF you wire this up into the EV - you effectively get a Series-Hybrid....

Now this all works great on surface vehicles! Check it out - most EVs are not light-weight! CERTAINLY heavier than most ICE-competitors in the same car-category....

HOW do you incorporate this into a aerial vehicle?

ALL-electric - no questions, just a balance of storage, weight, time - as soon as battery tech is at liquid fuel storage density/weight, the electric replacement runaway will start!

Hybrid? Well, what do you want to do with it? Remember "RECOVERY" is the general 'gameplan" of hybrid...

With planes - what I see- the general plan is to safe fuel on taxi-operations, driving via wheel-motors.
The same motors could be used to partially charge the batteries on the landing-deceleration.
That's on BIG planes. On smaller planes the calcualtions become very tight.....

On rotary aircraft I can only see one application where a hybrid would be interesting - maybe - and that is in a somewhat emergency situation - one you would like to avoid in the first place...

So - in my opinion - at least at the homebuilt level "Hybrid" is not going anywhere or is even counterproductive if you try...
NOW - full ELECTRIC is definitely underway!!! And it is exciting as you can do quite a few things you couldn't with ICE....

thjakits
 
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