Chickens, home, roosting.

The conventional helicopter and especially its turbine versions has long been viewed as beyond reproach, though here is one issue that eVTOL will never be susceptible to.

Whilst still an Airbus pilot I went to a conference at Cranfield attended by any number of sufferers from, and experts on... contaminated cabin air. Some of the best-known names associated with the campaign no longer appear in Google search for the simple reason that they've died prematurely.

At the time, those organising or airing the issue were made to feel about as welcome in the airline industry as the witches were in Salem.

The issue though was simply this. All airliners are pressurised, and the pressurised air is drawn from the compressor section of the jet engines. Should their oil seals leak then super-heated oil vapours containing neurotoxic chemicals are released into the air that we've all to breathe for a half-dozen hours or more.

Naturally pilots and crew were most exposed to the effects, but there were workers at the conference from oil-rigs, where turbine-powered systems did the air-conditioning.

As jet-aircraft are often in service for decades and involve budgets of billions, this was a lot easier to cover up than to fix, as we've come to learn with tobacco, lead in fuel and most recently global warming.

Now though even military helicopter pilots are suing the UK Ministry of Defence over the illegal effects of prolonged exposure to the emissions from turbine engines.

I've spent half a lifetime in aviation, and regardless of how shiny it appears from the outside, it's as corrupt as any other human endeavour.

Among our organisations and industries, crime syndicates are at least honest about what they do.

https://www.theguardian.com/uk-news/article/2024/may/29/mod-sued-over-allegedly-carcinogenic-fumes-from-military-helicopters

Re: view

It's been a worthwhile exercise, if only because in future I'll revert to square-section cantilevers which form an independent four-pronged drone.

With an outline that encapsulates the top end of the space-frame, it could therefore be dropped directly on top of it to secure.

This means too that the brackets can be dispensed with, along with the paraphernalia used to clip them to the topside of the passenger booth.

I'd like to get a handle on just how much more efficient co-rotating propellers of this kind are, as compared to contra-rotating.

Nonetheless the benefit of continuing with the current design ~ and I'm too far along to revert to any other ~ is firstly that the underslung propeller is well clear of the pilot and secondly that the leverage of the combined pair is greater than a co-located type.

Moving along from this 3/4 scale mockup, my preference is to try a full-scale version that can at least be sat in even if it has only the power to fly unladen.

It would look more like a step in the right direction, although it would involve a switch to carbon-fibre tubing.

The one benefit of it being populated by a pilot cabin, though, is that drone and cabin can be built separately.

Tho' as it won't happen any time soon, I'll post it to the VFS database for the record.

Homebuilt Helo #52

I make the decision to render this airframe as a non-flying mock-up, or visualisation.

More on that later, but for now I start by clipping a dog-bone bracket to each arm of the drone, and fixing a tin of tuna and a (floor-laminate) pretend propeller to that.

Readers are advised not to launch aircraft from a cliff powered only by tuna tins.

Digital Commoner

Of those papers I've posted on the digital commons, the one attracting the most views is https://www.tdcommons.org/cgi/viewcontent.cgi?article=7886&context=dpubs_series

The commercial concerns downloading this include major helicopter manufacturers as well as a company that builds access platforms, or 'cherry-pickers' to you and I.

What this demonstrates I believe is that irrespective of the arrangement of drone that provides the lift, there is a future for eVTOLs that suspend a standing human operator.

And I say suspend, because there are any number of prototypes out there which have flown human operators and feature the airframe beneath a standing operator.

For those of us who've spent a lifetime flying, though, the principal problem with this is the fact that if all else fails it ends up falling from the sky with its operator beneath it... which is not the ideal way to hit the ground.

Most helicopter designs include two principal features viz. (a) power-plants up top and (b) a rotor up top, because it provides (a) more room for payload and (b) a safer means of unpowered descent in view of failure i.e. right way up.

I'd add a third to these desiderata, which is that the arrangement shown in the paper linked above promises as compact and portable a helicopter as you could hope for.

And that's why ~ if you're to be a fellow traveller on our journey ~ it is worth persisting with the passenger frame with a seat because (a) it suits the recreational market that it might address and (b) it is easily adapted to the outline appearing in the paper.

Furthermore when goods were first containerised in the 1960s it was never certain the idea would take off, yet now everything comes containerised. With eVTOLs therefore, for the first time ever it's possible that people-carrying drones be adaptable to space-frames of various sizes and including either a standing or a seated passenger.

Take a look and leave a comment ~ I for one won't be reading them.