Airspeeder Fly-By... Night?

The official UK accident report relating to the Alauda Airspeeder Mk 2 display flight at the Goodwood Festival of Speed was published this week. It's a great photo of the south coast of England, although the UK CAA's exemption on the day allowed for a display not exceeding tree-top height... thus it appears our trees are taller than anyone else's.

The report is decidedly thorough, in contrast to either the operator or indeed the regulator on the day. Perhaps the scariest aspect is the fact that Alauda described the aircraft as failure-redundant given that it featured four motors... and I wonder whether the UK CAA realised that while airliners with four engines are as failsafe as possible, quadcopters are not at all.

Second point of note is that ~ notwithstanding the flash website ~ the operator was described in its submission to the CAA as comprising a CEO, an assistant and a number of university students. This alone speaks volumes about the 'wild west' that is eVTOL as compared to conventional aviation (or indeed radio-control modelling).

A third point of note is that the CAA themselves, prior to witnessing this flyaway from the relative safety of the 'prawn sandwich' enclosure, already hosted a drone recovery website that told of how over a quarter of pilots had lost a drone... which meant from the UK AAIBs calculation, some 14,000 had gone AWOL in the space of time airlines had only mislaid one Boeing 777.

Reading the report I'm glad only ever to have tested these things under a roof of some sort. The only issue is, some of the AAIBs criticisms are likely to steer development toward the level of regulation likely to strangle experiments at birth.

 

(Among these were the fact prototyping circuit-boards were used in the aircraft ~ but then what else do you use in a prototype? Or that nylon lock-straps were used to attach the ESCs ~ whereas I know from experience that such units include no distinct means of attachment, which is more the fault of the manufacturer).

Incidentally, the UK company set up by Alauda for the event (and appropriately called 'Riotplan') has already ceased to exist. Australians are clearly more aware than we of the perils of shitting on your own door-step.

Joy Be

Joby have raised a further three-quarter billion dollars of investment this week that raises the company's value to some 6,600,000 dollars. How does that affect bottom-feeders like ourselves? Well, principally by advertising the notion that we shall soon be exposed more often to the notion of 'vertical take-off and landing' types of electrical vehicle. In which case building one in my conservatory ~ as I am doing now ~ looks just that bit less deluded.

Boxing Clever

There's not much to choose between a place to stand in and one that can be sat in, but the former is structurally easier to accommodate and sits well with the original concept. I've split it in two halves, with this lower section rising to elbow height like the prototype test-flown in Llanbedr.

The upper half will be formed of an open space-frame, and at this stage need not solely bear the loads transferred between upper and lower drones, as these can be carried by struts affixed to the forward and rear ends: not unlike those that linked the two airfoils that comprised the biplanes that introduced the original notion of flight.

This half-scale enclosure that will encapsulate the lower half of our dummy measures a half-metre high by a quarter square, and is attached permanently to its quadcopter. Eventually the whole accommodation will take the form of a removable container so as to make the assembly more practical as a personal air vehicle (PAV).

For now though it will merely be detachable from the upper half so that the chassis seen here will fit through a standard doorway, as functional design starts right here.

Perseverance

NASA just landed the rover 'Perseverance' on Mars, and it includes a drone that is expected to fly even though the atmosphere is a hundred times thinner. Admittedly the gravity is just a third as strong, but whichever way you look at it you have to say that it puts most of our efforts in the 'umbra'.

So surely I can get someone airborne, two years on from conceptualising the notion and practically a year after the GoFly event at NASA's own Ames airfield? Once more unto the bench then, as Shakespeare might have said were he building a drone too.

This is the bottom end, which is set to provide nothing but lift ~ itself a novel concept among the designers of air vehicles such as these. Everything you see here in ensuing days is aimed at making the original notion ever more accessible in the making and in the operation.

There are two principal aims viz. (a) to suit the weight to a realistic test-program that falls within the CAA's own classifications for so doing and (b) to incorporate the best of all that has been learned (albeit the hard way) over the foregoing months and years.

Accordingly I've gone conventional with this quadcopter and arranged its 32" props on each corner of a square metre. Its direction of travel is also conventional for H-frames and this supports the use of an equally conventional set of skids. Its around 78" long and 46" wide and thus an approximation of a half-scale prototype... for which I've an upright mannekin to suit.

I would have used rectangular alloy section instead of square, yet another remarkable thing about this latest build is that all such lengths are repurposed from the previous efforts. I've also used the thinnest sections available, meaning the chassis seen here can be lifted with the little finger of either hand.

Enough for one day I feel (and the builds are faster than ever given previous practise), and thus tomorrow will see the flight compartment assembled and attached thereto.

New Model? Ah, Me...

Reviewing the available materials and looking at what has been learned over the past twelve months, I figure that it's worth another shot.

Accordingly the plan is to build a half-scale model with an underslung and overhead drone, for which I've the dummy and sheet material for the lower quad.

This will provide lift only, so as to render the payload near-weightless. In theory this should allow for a commercial off-the-shelf (COTS) drone of proven functionality to steer the airframe from overhead.

This in turn means that the 'pilot' drone might be altogether smaller and less powerful although the propeller axes might still need to be extended coincident with the lower (and much larger) set in order to provide sufficient moment.

Once more unto the breach, therefore.

And reinforced now by Pfizer-BioNTech's Covid-19 vaccine, what can possibly stop me?

Put Out the Moon...

...and dismantle the drone. It's been like gutting a snake, as I've needed to preserve the wiring loom that services one half of what was formerly wired as an octocopter, as an independent quadcopter. I shall probably take the opportunity to rebuild it using better materials at the same time, before performing what could be considered the world's first quadcopter transplant.

It's a crying shame to undo work once done, which is why I have kept at least half of the pre-existing wiring loom intact, which won't need much in the way of modification to operate as a quad- instead of an octo-copter. Invention is nothing else though if not a process of creative destruction and boldness is often called for in its execution.

Once reconstituted the uppermost quad will be available to testing unregulated in the UK at under 25 kilos, and then even after attaching to the seat and lowermost quad will still fall within the category of large radio-controlled model. Once there is someone onboard then that would have to be upped to experimental category, but not in this initial form when it might transport a lightweight dummy. Thus we have a path toward what may be considered a conventional test-program, which is what these developments require if they are to have legs.

Either way, if this final iteration (in which the uppermost drone is tasked with steering and the lowermost with lift) fails to work ~ and I'm taking a punt here ~ then it has to be my last.

But let nobody say that we didn't try!

Transfer Window

It's traditionally during a period in January (actually as of midnight yesterday) that soccer teams in Europe have to finalise transfers of players between one team and another ~ so that for instance the loss to injury of Virgil Van Dijk at Liverpool FC has prompted the purchase replacements from Istanbul and Preston respectively ~ and it behoves me as project manager to do the same.

In fact I had no choice in some respects, for the consultancy who wired the prototype that half-flew at Llanbedr's test-facility have declined to participate further. Don't read too much into that, however, because (a) it's a question on the one hand of their own imperatives as the market for their cargo and survey drones grows apace and (b) the split is over 'artistic differences' so much as anything else.

Viz. I believe that the task of building people-carrying drones is aided and abetted by splitting the problem in two, and tasking the uppermost drone alone with steering the vehicle whilst the lowermost merely provides much of the lifting power (which is the more easily engineered altogether). It's a walk-before-you-run philosophy.

That said, each iteration is much like an exorcism in that it leaves participants drained that little bit more, and less able to face the other species of shit that life has to throw at us whilst we're building drones (as John Lennon might have said). And they have spent a lot of time in the recent and distant past on prior archetypes, so that frankly I don't blame them.

In this game you've to play Devil's advocate, and I would be saying to me if I were any other, "Stop picking around, pick one particular outline and get on with proving that you're not on a fast-track journey to nowhere!".

Bit harsh... but true, and accordingly I shall revamp the website to suit and get on with the '21 build prior to announcing my new team line-up.

And already I like that phrase right there: GET ON WITH THE '21.

It's the new motto.