HUGE #10

Don't know whether you can make that out but to save time I popped a line of glue along the lower edges of mainplane and tail-fins so as to drop the hydroskis on and next day I'll flip it over and filet the edges.

Note how tail assembly, lateral spars and hydroskis all terminate at the same place in order to satisfy one of Colin's golden rules viz. Person or persons building a drone shall ensure it can be stood upright, inverted or on a tail-end for maintenance or for storage at pain of imprisonment or fine not exceeding two-dozen Eccles cakes.

The 80/under-20 Rule

Accident yesterday in Scotland in which two people died ~ the one 80 and the other 16 ~ caught my eye for reason that the first of those numbers resonates: people over the age of sixty-five are responsible for 80% of all heart attacks. As a man, worth knowing too that 70% are suffered by men as against women.

Weather yesterday afternoon out of Glasgow ~ I've been based at the airport and run Ben Lomond northwest of the crash location on a summer's eve ~ looked to be insignificant with practically no cloud reported and twilight some way off.

Sadly I don't pay the premium for after-casts on FlightRadar24 for the Tomahawk ~ again a personal favourite among light aircraft ~ because the altitude data would be telling.

Nonetheless the track some way along the periphery of Loch Lomond looks wholly erratic in itself. Bear in mind too that flying is not a stress-free activity, and is the more likely to raise blood-pressures as and when passengers are involved.

Accordingly it would appear unlikely that the pilot ~ which I'm assuming is the 80-year old as you have to be 17 for the licence ~ would be prone to undertaking any series of steep turns for the fun of it.

(There is a possibility that both were pilots and the younger doing the flying, though it would be from the un-instrumented right seat unless the 80-year old were also an instructor... stay with me on this.)

But one way or another, I would have to guess it's the older of the two flying. Given that, I've had two engines stop on me in single-engined aircraft like this, one fixed with a subsequent restart (having been due to inlet icing) and another ending in a forced landing at Luton Airport.

And nothing much from the aircraft's tracks looks like anything that would explain a partial failure (and likely return to Glasgow), nor what you'd want to do should the engine have failed.

We don't know either where the aircraft was headed, but in visual navigation terms and sat on the left, you're following line features like the edge of Loch Lomond. This is in fact what happens until a drift over the lake and abandonment of progress that had largely pursued straight lines.

There is then always a possibility of a medical turn for the worse resulting in either (a) the pilot continuing with decidedly degraded performance or (b) the pilot having conked out and the 16-year old passenger having to assume the reins.

I've taught people to fly single- and twin-engined light aircraft and jet airliners and what is immediately obvious to anyone doing so is that the uninitiated lose control of direction rather than height in the first instance... note that the recent hijack of a Boeing 737 in the Middle East involved a passenger recovering from the death-dive rather than any pilot, and on the basis of what he'd only seen on TV.

Aircraft tend to be stable in (vertical) pitch but unstable in (horizontal) direction, which is how the Wright Brothers used to crash. Turns in aircraft also demonstrate negative stability in terms of the fact departures from straight and level are inclined to get worse instead of better.

This is compounded by the fact inexperienced pilots finding themselves at a steeper and steeper bank angle and tighter and tighter turn instinctively pull at controls and so inadvertently tighten the turn. At the same time the nose of the aircraft drops and so speed increases, in some cases to point of break-up: it's called a 'spiral dive' and like the stall is what killed any number of the earliest aviators.

But back to my 80/20 rule: if you're under twenty, you really don't want to get into an aircraft with anyone who's turned 80.

Or me for that matter.

HUGE #9

Here I've bonded the edges of each plane to the lats and added a bead-come-filet to secure in the aftermath. I've no clamps of the right size and have thus used ballast to hold the lats in place because I've used them elsewhere and they've retained the bend they had in one direction as a consequence.

Note the use of polythene bagging, which is impervious to practically every form of glue and thus prevents us from gluing the craft to the workbench. In times past I've managed to glue builds to the laminate floor of the lounge, which does though lend a Brit Art feel to subsequent dinner parties; in Chelsea there'd be at least one guest prepared to invest and take it home.

There are fast-build methods that involve framing each panel in timber so that parts can be screwed together with no waiting for adhesives to dry, but this model will be used largely to inspire the punters and drop in the bath to see if it floats.

HUGE #8

We now ask ourselves how far the tailplane need be from the mainplane, a question we've been asking ourselves since the Wright Brothers first moved on from mending punctured inner-tubes.

At times like this I like to go broad-brush or big picture and bear in mind the Skunk Works dictum of it looking right and flying right: I've therefore taken a punt on making the intervening gap the same as the width of each plane viz. 450mm or around 18".

I've always wanted the mainplane to be around the mid-point, and in fact it's one of the easier tick-offs on my before-I-die bucket list. It means that the overall length is going to be around 1.50 metres or five feet, which has a 'golden mean' feel to it and is a proportion I feel that Michelangelo would have aimed at with his own maritime drone.

It also means that ~ all being well ~ it should fit the bath-tub earmarked to become one of the largest hydrostatic test facilities in the North of England and which ~ due the UK government's refusal to finance it ~ lies abandoned in the garage.

Nonetheless if we look at the outline of the world's most successful airliner in the shape of the Airbus 320 ~ one or other variant of which I spent over seven thousand hours of my life in ~ we'll see we're not too far adrift from conventional methodology... the larger A321 pitches the mainplane more centrally again.

 

Footnote

Ed. He's left the building, dear reader, and too late to spot his humble blog exceeds a million views. Every night now he'll lie in bed, the brightest colours filling his head, because a million views are keeping him awake. And it's all thanks to you, the bots.

HUGE #7

Here's our second sub-assembly and as artist and all-round Ozzie entertainer Rolf Harris used to say before being arrested for paedophilia, 'D'ya see what it is yet?'.

Now however we've happily to wait for this to set; which we didn't do long enough last time, did we Gromit?

Accordingly it's time for a glass of Chianti and somebody's liver.

Good-night Teddy, good-night readers! 

HUGE #6

Here's the first sub-assembly, joined by the time-honoured method of a squeeze of Stixall where the pontoons meet the surface of the airfoil ~ with a gentle squeeze so it appears from the sides like the filling of a Victoria Sponge ~ and then a filet to one side with another to follow later. I've emailed Bake Off judge Nigella Lawson to ask if she'd like to give my pontoons a gentle squeeze, but am yet to receive a reply.