On Wed, 05 May 2021 06:22:15 -0700, Eric Greenwell wrote:

On 5/5/2021 12:20 AM, Martin Gregorie wrote:
On Tue, 04 May 2021 19:29:42 -0700, Guy Acheson wrote:

Same with cars. Solar panels covering the surface will recharge the
batteries continuously for free.

Sure have - but lightweight, single seat vehicled with large, flat top
surfaces covered with solar cells. Specially designed to race across
Australia.

Airplanes have already demonstrated powered flight with all power
coming from solar panels.

Yep, and one even flew round the world on solar power. But lets not
forget that it was huge, a single seater, flew at 35-40 kts and took
weeks to finish the journey.

Just like unlimited power from fission...it is only 10 years away.

Thats the problem with the kids who should know better - they're unable
to distinguish between a hobby/proof of concept vehicle and something
you can buy right now and drive to Vegas for a weekend.

Isn't it wonderful to read about all those VTOL electric cars that will
be available for anybody to buy and fly in four years time, but right
now only exist as shiny graphics plus a price on some website? Not!

Sometimes, I wonder what was said when automobiles were one-offs and
horses provided the local transportation for people and goods and trains
for long distances. Imagine how impractical they were in the beginning:
poor roads, no fueling or repair stations, very expensive. And not safe
to use while drunk because you'd crash, while a horse would keep you
safe, maybe even get you home.

I think you're missing my point: there are a couple of eVTOL aircraft
that have been flying for several years, not yet certified but planned to
be on sale in four years or so.

I'm not talking about the Terrafugia either - that does fly - or even the
Moller Flying cars, which Paul Moller has been building for getting on 50
years: these have flown, though never without a safety tether and never,
AFAICT, with anybody on board.

As I said, I'm not talking about them. What I AM pointing the finger at
are several whose entire existence seems to art on a glossy website with
no news about financing, construction, or test flying development
progress yet with promises to be on sale on four years time at already-
announced prices.

These are the projects that deserve critical examination, not rave
reviews in glossy magazines.

One that comes close to this is the Alauda Airspeeder
https://alaudaracing.com/

This was a 1/3 scale prototype was built and flown, but crashed, thanks
to poorly thought systems which were also badly implemented. There's an
AAIB report about it, which is worth reading as an object lesson on how
not to develop a prototype aircraft:

AAIB investigation to Alauda Airspeeder Mk II, (UAS, registration n/a)
040719
https://www.gov.uk/aaib-reports/aaib...da-airspeeder-
mk-ii-uas-registration-n-slash-a-040719



--
Martin | martin at
Gregorie | gregorie dot org