Electric Boogaloo part 2: R44 Edition

[lelebebbel]

A Robinson R44 converted to electric drive with a 70kWh battery has made it's first successful manned (5 minute) test flight at Los Alamitos Airfield:

https://www.youtube.com/watch?v=-05wY41ht1s

Newsroom | Tier 1 Engineering (http://www.tier1engineering.com/news/093016.htm)

-05wY41ht1s

[Ian Corrigible]

Silent flight indeed. They've achieved what the Firefly (http://www.pprune.org/rotorheads/421752-200hp-electric-sikorsky.html) never managed to.

I/C

[riff_raff]

I don't mean to downplay the work put into this project, but I don't understand the reason for spending a substantial amount of money on it. In reality, all they did was retrofit some batteries/motors/controls based on existing products available in the commercial market, to an R44 helicopter. Unfortunately, their aircraft demonstrated a level of performance that is entirely inadequate for any application. What value is there from this level of effort?

It would seem obvious to any rational rotorcraft designer that until battery technology makes significant advancements in weight and power density, a truly viable battery-electric rotorcraft will not be practical. Electric motors and controls are currently good enough, but batteries are not. So what is the point of these efforts?

[Vertical Freedom]

& that on a Crapinson, well that tells lots

[Bell_ringer]

With early research like this the goal is to prove it can be done and hopefully learn a few lessons that can be applied later. It makes sense to use a light piston due to cost but also you get a good weight saving by yanking out a heap of pig iron from it's backside.
You wouldn't save much by removing a light turbine and the drive system would be a bit more difficult to integrate with.
The battery system looked fairly agricultural, I suspect they must have a bigger plan - no one burns cash just to make a Robbie less offensive to the ears. :\

[[email protected]]

Now how about they mount solar panels on the rotor blades and fly it round the world......

[cattletruck]

I'll wait for the wind up - version that is.

[Copy that]

So instead of being burned to death in a fuel-fed fire following an R44 crash, do we now run the risk of being electrocuted?

[mickjoebill]

So instead of being burned to death in a fuel-fed fire following an R44 crash, do we now run the risk of being electrocuted?


You don't need a crash to trigger a fire in batteries!


Mickjoebill

[RVDT]

Electric powered Türd from an Avgas powered Türd?

All the polish in the world will not fix it.

If this is the answer what the hell was the question?

[[email protected]]

Perhaps they could try rolling it in glitter........

[WillyPete]

Done before on the 300C - Firefly.

oD8TfjDMYT0

https://www.youtube.com/watch?v=oD8TfjDMYT0

http://www.sikorsky.com/Pages/Innovation/Technologies/FireflyTechnology.aspx

15 minutes flight time, near max weight with the batteries.

Only way this will work is when a new serial/parallel hybrid drivetrain makes it viable, with a battery reservoir for needed power boosts.
The generating engine needs to be VERY light, as does the motor.
The only benefit it will really bring is to remove the gearbox, clutch and linkages. So it has to come in under those weights when you've added a generator/alternator.

So to replace a 3000hp powertrain, you'd need a 3mW electric motor on the hub, and a turbine or similar rated to supply that amount of electrical power.

As for "Why a robinson?" well, it's not feasible trying to replace turbines just yet, but the less efficient pistons are a prime target for the tech as it matures.

[500e]

If they could supply spares for the existing it would help :{

[MLH]

Congratulations to the engineers at Tier 1 - maybe these clever guys can design a set of Robbie main rotor blades that can make it to TBO.

[onetrack]

Now, if they also installed a pedal-powered generator operated by the pilot, we'd really be rotoring!

Then they could attach one of those bumper decals that reads, "Quit complaining! I'm pedalling as fast as I can!"

[Stanwell]

With the advent of new materials and technology...
I've dusted off the plans for the new and improved Stanwell Mk.IV high pressure, steam-powered ornithopter.
Coal prices have stabilised and, if I can just get my stoker to lose some 30 kilos of weight, I think we might just do it this time. :cool:
A detailed prospectus will be promptly forwarded to those interested in taking advantage of this unique and potentially lucrative opportunity.

[onetrack]

Stanwell, the Doble Model E Steamer is still a very viable design with a bit of modern technology input. Even the existing Dobles are marvels of engineering, and very efficient. Maybe if Ab Doble had dabbled in helicopters, we just might have had steam-powered choppers today!

I have little doubt that we are in the age when electric power will become very viable in many fields, but perhaps hybrid power will be the winner in the near-term. After all, the actual HP requirement for a lot of steady motion is relatively low, and IC engines waste a lot of power and energy by running at near full-power output when that full power is not actually required.

[Stanwell]

Thanks for reminding me of Ab Doble, onetrack.
As a follow-on from his work, the Besler brothers successfully converted and flew a steam-powered Travel Air 2000 at Oakland, California in 1933.

A civilised way to go, I think.
Y'see, while one is waiting for the boiler to warm up, it affords the opportunity to partake of tea and crumpets while having another look at the met forecasts
and, if necessary, review one's flight plan.

Besides, NVH is all but eliminated - further adding to passenger amenity.

.

[riff_raff]

Historic first flight of a recip steam engine powered unmanned helicopter by Enrico Forlanini in 1877. Silk fabric, hand carved wood, and genuine copper/brass fittings. A very civilized way to go indeed.

http://www.museoscienza.org/dipartimenti/catalogo_collezioni/images/as_07330.jpg