60" Build Step #4

It's time to get jiggy with it, and we've turned to the longer lengths of alloy here so as to arrange them four-square using a set of, well, set-squares that do what they say on the tin. Note that the ends just kiss each other rather than overlap, because the tube connectors will go that last mile. Well, inch actually. Looking at the image at centre it can be seen that I shot myself in the foot with that 38.125" measure for those shorter lengths, forgetting the overlap.

I've taken an inch off all round however and note that in the final picture the parts are laid out to my total satisfaction and set upon one of the two 19" sheet-alloy squares. Finally note that we should mark the margins of that centre-section with a pencil as a guide, as we are about to slip it out from under there and place it up top ready for the riveting.

60" Build Step #3

N.B. THE FOUR ARMS SHOULD HAVE BEEN 37.125" INSTEAD OF 38.125", SHIT HAPPENS.

Well with that out of the way, let's move on to construction of the 'drone itself and we start by taking those arms and applying a squeeze of silicone around the inside edges of all eight ends before tapping in the threaded M6 inserts... from which I have to say the average fabricator will draw a practically sexual satisfaction (or at least until those rivets are driven home).

I've opted for 4 x 12mm pop-rivets as a good all-rounder, and a 3.9mm drill-bit offers the tightest fit, although I've gone for a 4mm bit as it is available on any desert island. Apply those rivets to opposite sides as a belt-and-braces fix, and we'll see later that these opposing pairs need to be oriented methodically during assembly.

Airworthiness inspectors might question whether this meets required tensional specs and should this be a sticking point. Offer to hang them from the rafters with the same method and if the joints prove to be up to scratch, then you're clearly the winner...

60" Build Step #2

There are three modules to the 'drone viz. airframe, flight-deck and undercarriage. The reason for this is that like the containerised transport system, the design features a four-cornered means of connection forming the basis of a modular system that offers (a) choice of undercarriage whether skids, floats or castors (b) choice of payload whether seat, stretcher or cargo-box and (c) choice of four or eight propellers.

Altogether, you're spoilt for choice. We'll first build the frame to which flight-deck and skids will be attached, the recipe for which module includes the following:

(a)    4 off 58" and 4 off 38.125" by 1/16th aluminium square tubing, cost £36.47

(b)    2 off 19" square 1.20mm plain aluminium sheet, cost £32.40

(c)    4 off 25mm four-way steel-reinforced tube connectors, cost £44.19

(d)    8 off 25mm square 6M threaded inserts, cost £5.87

(e)    8 off 6 x 40mm hexagonal bolts at £0.40

(f)    Total metal/plastic parts airframe, £119.33

That's just half the cost of lunch at a Michelin-starred restaurant, and you can't share that. Leave those ingredients indoors overnight, as warm alloy is more workable.

60" Build Step #1

Pays to draft the outline at the outset and I've done so in Apple Pages, whose elements a chimpanzee could grasp. I am actually old enough to have worked with the Vydec dedicated word-processing system that could output text to the printer for an equivalent outlay of $60,000... so Pages is rocket-science so far as I'm concerned.

I like what I see, a caveat being I may stretch the central square to 50 cm instead of 19 in (because the sheet-metal supplier does so in metric).

Going to be a leisurely build, but I'll hold your hand throughout.

Go Big, or Go Home.

Few people watching the 2022 Winter Olympics will be aware of the significance of the name, but Jake Burton effectively invented the snowboard, or indeed the sport of snowboarding. Like every other groundbreaking development, most or all of the parts were already there to the extent that what remained was ~ as it had been with every other form of locomotion ~ for someone to come along and demonstrate the possible.

What the HBO documentary Dear Rider makes clear, however, is that the earliest years were in the words of the inventor, decidedly lonely as he investigated various forms of manufacture and shipped in dozens a product that would come to be sold in millions. In truth, the sport never really took off until such time as he collaborated with a small ski manufacturer in Austria called Kiel, who could apply conventional fabrication when every other ski manufacturer had dismissed the notion of the sport going mainstream.

There are parallels now in the polarisation between moneyed air-taxi developers and the comparatively impecunious of personal air vehicles. But what developments like the snowboard demonstrate is that the public at large rarely see which of them might succeed, except in retrospect. Donating prototypes to museums has therefore closed one phase of development, yet at the same time calls for the next.

For what is life after all, without a project?

Nothing Ventured...

I donate the second of the prototypes to Aeroventure, or South Yorks Aircraft Museum in Doncaster  based on the site of the historic airfield... a place where, for instance, all of the wartime DC-3 Dakotas were modified for use by the RAF (to right-hand drive?). 

For me though in the late 1970s it was a place beside the race-course that the crew-bus passed by enroute to Finningley. Each airfield was established by the Royal Flying Corps in WW1 and are thus amongst the oldest in the UK, if not Europe. On a more modest scale altogether it was where I first took to the skies myself: at the controls of the venerable Bulldog and alongside Squadron Leader and Spitfire pilot, Ron Brown.

Like so many exhibits this is a sum of its parts, its duplicate in the Helicopter Museum bearing the original airframe, and this the motors and propellers used in that test-flight of December last year. I like the fact it hangs here from the ceiling, and in the very best of company in the form of Bell's 47.

Enstrom Ending?

Appears Enstrom ~ a company as old as myself ~ is yet to rise from administration like a phoenix. The company was started by someone with no knowledge of aeronautical engineering, but ample enthusiasm (which gives us all hope). But it was the steed of choice for Dennis Kenyon, who passed a year prior to the demise of the company.

I've chanced upon some remarkable pilots unknowingly in years past. One an old man whom I used to pass with a cheery greeting outside the hangar in Bournemouth we were both frequenting whilst he was flight-testing a single-engined turbine aircraft. It turned out to have been Neville Duke, one-time holder of the world speed record.

Dennis I also shared hangar-space with whilst scratching a living a fixed-wing QFI. He returned to flying helicopters later in life from necessity, and for the same reason most men of advanced years with whom I once shared a cockpit did so: divorce. But I witnessed one of the most heart-stopping aerobatic displays I have ever seen, before discovering only now ~ some thirty years on ~ that it was a world champion that I was watching.

I recall how telling me that to refine his craft on the Enstrom they would fix a strip of balsa on the tail-boom to see how close during maneuvers the main-rotor came to slicing through the tail-boom.

We shall never see his like again... or theirs.