Been a year as of tomorrow since I formed the company with a view to this venture and I am surprised at how much ~ and equally how little ~ progress I've made.
With the electrical equipment out of the box now, here's an email to my team-mates and shareholders that is as good an update as any:
Gents,
Apologies for what appears to have been slow progress on all fronts but there are times you need to ‘step away from the vehicle’ and reflect on the way forward.
The motors and propellers and speed-controllers (ESCs) are landed from China, and to look at them is to realise that electric flight (and cars) really are the next big thing… the 32” carbon-fibre propellers are so light I figured the boxes were empty, and the motors at 4-inch diameter will raise around 20 kilos apiece (and we’ve eight).
Taking everything into consideration I figure the initial prototype has to take the form of a simple ‘flying carpet’ as per the attached, which is suited to a seat although a podium is not out the question.
With this up and running the fundamental design is adaptable to top- and mid-mounted positions around any form of vertical space-frame, but I like how this looks as a way forward.
Happily the eight-legged layout (basically two quads bolted together) also appears to have been wholly unique from the patent point of view beside promising more stability and redundancy.
The dimensions are well within the fly-off regs (which the ‘flying phone box’ variations generally weren’t) and the airframe is only around five feet square with props stowed as shown and therefore roof-rackable and flyable out the garage door.
We also have barn/workshop/flight-field facilities available to the project with a chance of on-the-spot accommodation… bit like the Wright Brothers at Kittyhawk, but without the sand.
The motors are driven by 48V so we’ve motor batteries available for ground-electrics and tethered tests, whilst the real-deal batteries will be sourced from a bespoke firm in Hong Kong.
A reason for the ‘powered-platform’ design is in fact that their weight (stored as ballast in the base) maybe as much as half my own weight for a flight of ten minutes in ground-effect.
The arrangement also favours the simplest possible flight-control architecture, with each propeller pair driving left-right-forward-back respectively and the throttle adjusting height alone.
Control laws for the engine-out case will have to wait and any failure prior will hopefully take the form of a tight-spiral descent to a softish landing with concomitant damage inevitable.
The lower set of propellers will also be shut down for take-off and landing with the upper set providing those manoeuvres, to avoid prop-strike.
(Ground-effect should assist this up to around one metre by providing a surplus of thrust of between 25% and 50%).
With an airframe complete in July we can then push for first-flight with or without tether and likely a seated mannequin, and having done this the type can be listed in global databases of such project builds.
The biggest players have spent billions of dollars to date on eVTOL types so we haven’t done too badly in the double-garage to date…
Contracts will also need signing this month as otherwise there’s no entry to the ‘pit-lane’ at the event itself in California.
C.
