James Dyson and the Harrier.
 

Not sure it had a carbon fibre wing back in the 60s though..

http://www.bbc.co.uk/news/technology-36257643

Composite technology came with the re-design as the AV8B in the early 80s so he's wrong, it wasn't around in the 60s.

... I'm still trying to work out what Dyson means when it says it uses 'Digital Electric Motors' :rolleyes:

Harrier Composite
 

I seem to recall that the advent of major composite airframe parts then caused a rethink in how it stood up to battle damage in the field; as what was a 'hole' punched into metal originally became a more serious problem when it shattered a composite component.

Dyson is a scroat with a tendency to marketing B/S to justify inflated prices.

His famed "digital motor" is simply a brushless DC motor - nothing that clever or unique. They are manufactured in the millions all over the world for uses ranging from robots and UAVs to radio-controlled toys. Every quadcopter "drone" has at least four of them...

PDR

Bushless DC motor, uses a switching speed controller.
Smaller, more efficient, runs cooler...

If it has more than four, is it still called a quadcopter?

Dyson is a scroat with a tendency to marketing B/S to justify inflated prices. - PDR1

Have just been in touch with James who laughed, and replied that you might like to look up the definition of a "scrote" in the Urban Dictionary.......:E

Jack

I first flew the plastic wing in 1979.

Nige ...

That's my point ... The physical motor is no more than a bog standard DC Brushless Electric Motor ... How you generate the field in the stator coil is another matter.

Marketing 'Hype' ... Pure and simple. The word 'Digital' has been/is being overused by the advertising industry IMHO.

Sorry for thread drift ...

Is that a digital thread drift, or simply an analogue one? On important issues like this, we need to know.

Nutty ...

01000100 01101001 01100111 01101001 01110100 01100001 01101100

Go figure :p

No, it can be called a hexcopter, octocopter or the catch-all multicoptor/multi-rotor term that is also used. For those with *fewer* than four it is far more common to hear them descibed as "multirotors" than "tricopters".

Well you did ask...

:)

PDR

Just typical - how are we supposed to have a typical internet rant-fest when you go jumping in with claims based on the simple matter of having been the man who actually did it, John. It's unfair!

:)

Actually I think I have photos of that flight amongst the piles I salvaged from Phil's bin when the Dunsfold photograph dept was closed down.

PDR

Yee I did smirk at the wing moment :}

I thought the binary might be more exciting than it was

Having now viewed the video - his comment about it weighing "five tons" was a bit off as well. I'm sure John can correct me here, but from memory I don't think a Harrier II has a flyable configuration down at 10,000lbs does it? Certainly the original 1127/kestrals had basic weights down there somewhere, but I'm not that sure if even any of the Harrier Is did.

At the other end of the scale I can remember the 34,000lb AUW (or was it 32,000?) clearance trials, but that's a different skillet of trout, of course.

PDR

I seriously doubt the Harrier in Dyson's company car park is even remotely approaching a 'flyable configuration'! It will have been stripped of it's avionics and other sundry classified/dangerous items at the very least and possibly it's engine too...

-RP

Coffman

What is slightly unusual is the speed Dyson's motors run at, over 100,000 RPM. I suspect the speed controller is doing some quite clever stuff measuring RPM and governing speed... I do know they get through thousands of prototypes of the airmoving parts....

There are plenty of electric motors (especially brushless ones) which operate at these sorts of speeds. And the controller will be either a sensored or sensorless brushless controller of the kind made in gazillions al over the world - known technology and nothing particularly clever. With a synthetic commutator (which is how a brushless motor works) you don't need to do anything clever to know and govern speed because you're nailing it in the control function.

Of course electric motors are *inherently* speed limited by the nature of the wind and the applied voltage anyway. I have a motor which can develop 1500watts at 8,000rpm into a 22" propeller from a 44v power supply. If I take the prop off and apply full power it turns at a whopping great...

...10,100rpm. That's all.

The effect of back-EMF as expressed in a paramter called the "motor constant" (Kv) means that the motor will never turn more than a certain number of rpm per applied volt of electrickery.

The rest of it is snake oil, of course. And purple plastic - that makes it very high tech!

PDR