Should have been done a whole lot sooner but on balance I've generally been building, and if you're building websites you're not building flying machines...
Monday, September 28, 2020
Wednesday, September 23, 2020
Well the next time I see this it should be in flying condition, although it's likely to be flying a dummy in the first instance as the motors are unlikely to support my own bulk except possibly within ground-effect. Nonetheless if and when it flies we shall be able to see whether it's a going concern... literally.
Monday, September 21, 2020
Come four o'clock and with a final sweep of the workshop, air vehicle and trailer are set to be transported elsewhere for soldering up and programming prior to flight-testing, and all in the teeth of a second wave of Covid-19 infections with whatever restrictions might follow.
It has been a little over three and a half months since the previous prototype was driven south ( http://teledrone.blogspot.com/2020/06/ex-works.html ) and though those plans went awry, we are in an altogether better position now regards both prototype and personnel.
Every step of the way from hereon in has to be designed for the rough-and-tumble of both road and air, and this applies to the logistics as is clear from the trailer. I would like to say the trailer was designed around the prototype, but if anything the latter has benefitted from having to fit the former.
This is not as strange as you might think. The much-delayed Bristol Britannia was drafted with seating for three-dozen passengers, because launch-customer BOAC felt it sat better with their existing fleet of buses back in the day when you were driven out to the aircraft. The buses sat three-dozen, which thus became the key specification.
It's what happens when you eliminate commercial probity from the equation, and one among a number of reasons why the golden age of UK aviation in the 1950s was turned gradually to lead.
Saturday, September 19, 2020
Shot of the bottom-end prior to conjoining with the fuselage and top-end. This conjunction will take the form of a permanent fix, though going forward each drone will be a plug-in assembly to fix to a separate passenger booth. As each drone will be wholly independent, the day will come when parts like this are programmed to fly to the customer in a means of re-supply that needs no van.
Thursday, September 17, 2020
I've rebuilt the airframe to slightly reduced dimensions and as a part of this effort had the skids turned up by one of the many engineering firms that thankfully still exist here in the northwest. This has been trial and error, and in fact a 10 gauge extrusion would have suited better then the 12, but we'll park that one for next time. It was in fact a further exercise in trial and error, the 6062 grade of aluminium not being disinclined to bending, but preferring to be annealed first, which was something that took me back to hardening and annealing in Engineering Workshop Theory and Practice (ETWP) back in my schooldays.
But driving back it occurs to me that drones don't actually need upturned skids, as nor generally do model helicopters. The principal reason for upturned skids on rotorcraft is to accommodate running landings, for instance during an autorotation following an engine failure ~ a generally practised manoeuvre in piloted airframes.
In contrast, the same level of failure in either drones or RC helicopters basically involves them dropping from the sky like a sack of potatoes, which doesn't require nearly the same finesse.
There are two reasons I shall continue to go to the bother of turning up my skids, however, and these are:
(a) because they look good, and...
(b) because they're useful for punting around on snow and ice.
As I see a market for these vehicles in and around winter sports arenas (for so long as they exist in a globally warmed environment world), reason (b) is not so implausible as you might imagine.
Length of those skids by the way?
Tuesday, September 15, 2020
Best thing about the modularity of this design is its sheer practicality, so that whilst the lower rig awaits the skids from the fabricators tasked with bending the horns at its forward end, I can get on with rebuilding the flight compartment and rigging the top end. As it stands too I can bodily lift it and carry it around the workshop, which makes such tasks easier again. Think I'm in love...
Monday, September 14, 2020
Bit of clarity in the ongoing debate in my head as to which direction this box should be flying, with it being rebuilt so as to be yet more compact prior to wiring for flight-testing. Like most people I'm wider across the beam than from front to back, which enables the outline of the 'box' to be reduced accordingly (at sixteen inches wide, but only fourteen deep). It thus naturally faces the direction followed by the extended rotor-arms, which therefore settles the case so far as this prototype is concerned at least...
Saturday, September 12, 2020
Fortunate to be in Lancashire, until recently the go-to part of the UK for aircraft engineering and home of the most renowned bombers of the Second and Cold wars in the shape Avro's Lancaster and Vulcan. Been having trouble finding people to bend aluminium, want upturns on my skids as I do, and it is here talking to a man who does it for a living that I find out why. Unlike steel or copper, it's not especially ductile and prone to brittle hardening as a result of both age and work. Also, the grade is a factor that is not nearly so forgiving as the range of grades of those previously quoted metal types. As a consequence, looking at the samples here and the right-most especially, you will see that the same batch has in one case been successfully bent through ninety degrees whilst another has failed at thirty.
Reflecting upon this I drive east into Yorkshire to take a look at the "Five Rise" series of canal locks on the Leeds-Liverpool canal in Bingley ~ built in 1774 and raising barges through sixty feet along the course of three hundred feet ever since.
They don't build them like that any more ~ and that's the engineers were talking about.
Wednesday, September 9, 2020
Tuesday, September 8, 2020
Not an old flame of mine but the technical term for the colour, as defined by the military in the UK at least. I shall revert to pillar-box red for display purposes, but this will suit for the flight-testing. Also the airframe I shall donate to some or other museum thereafter, and it won't look out of place at Middle Wallop for instance... the spiritual home of the Army Air Corp in this country (recalling too that the Royal Air Force began life as such, and that the British army reputedly have more airframes then do they).
Also pundits have let slip the feeling that flying phone-boxes are a little too fanciful, quoting the brothers in Germany who recently flew a bath-tub by similar means. What most of us do not realise however is that they likely chose a bath-tub as a ready-made alternative to building something altogether similar but at great cost in terms of both time and money. When I taught in flight simulators or "synthetic devices" the manufacturers of such were rapidly subbing COTS or Commercial Off-The-Shelf components for what were previously bespoke... so don't knock it.
My preference has always been for motors mounted upright, too, but whilst this is an option for larger accommodation boxes supporting enclosed operators whether standing or seated, it was clearly not an option here for safety reasons. But why this version anyway? Well, to reiterate ~ anything larger falls foul of the (restrictive) dimensions allowed by the ongoing GoFly challenge.