h a l f b a k e r y
Renovating the wheel
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There is a modestly popular televisual series called "How Do
That?", which explains how people do things like building
bridges, digging tunnels or producing 25,000 fish-fingers per
with "How It's Made", it addresses the many hows of modern
"Why Do They Do That?", a series which explains
the reasons behind
all the mysterious things that workmen and officials do for
purpose. For example, why do they leave roadwork speed
place when it's August and all road repairpeople are on
holiday? Why do
they close the boarding gate thirty minutes before
departure, then leave
the plane standing there until 12 minutes past departure?
Why do they
retract the landing gear as soon as the plane leaves the
ground, but lower
it 20 miles before landing? Why do lorry drivers on 2-lane
overtake each other at a speed differential of 0.2mph,
regardless of the
slower lorry's speed? There are of course excellent reasons
for all these
things, and it would alleviate some degree of angst if we
were all told.
||// Why do they retract the landing gear as soon as the plane leaves the ground, but lower it 20 miles before landing? //
||<Jumps up and down, waves hand in air/>
||Oooh ! Ohhh! We know this one !
||On takeoff, the priority is to reduce drag as much and as soon as possible, to maintain airspeed in the climbout. The high-lift devices go/next, to clean the wings up. This allows a power reduction, ostensibly for noise abatement but actually to try and prevent the engine(s) from making an Expensive Noise of a quite different sort.
||In aircraft with fixed undercarriages, instead of retracting the undercarriage it is the tradition for the pilot not flying to criticise the pilot flying for poor technique, inadequate personal hygiene, lack of sartorial taste, but most of all for selecting an aircraft with fixed gear.
||On landing, it's best to have all drag inducing features activated while there is still a good bit of air underneath the plane, making it possible to adjust engine power (if any) to hopefully give a less uncontrolled rate of descent. It also allows the crew to resume breathing when the "three greens" (gear down and locked) hopefully appear. If they don't, see the previous paragraph on criticism of the pilot flying.
||Yes, [8th], we know you know. We were hoping you'd let
someone else answer.
||I'd always assumed it was because you can tell pretty
accurately when you've taken off, but it's difficult to know
where or when you're going to land.
||The idea is about an internet video show not about
annotations in a black and white no hyperlink python
run website from the former century luckily for me
with no votes enabled on comments.
||For 8th's Anno to count you need to see him at the
computer all exited with his own voice over reading
the question while in the background you see
various types of aircraft retracting their wheels on
takeoff and leaving them out on return. Then the
program narrator says stay tuned and we'll be back
right after the advertisements.
||A witty program would have an advertisement for air
travel. When continued we are at an airport watching
from a drone focusing on something near the
runway. It's 8th waving wildly and yelling me me!
||Now we watch a few famous accidents and a
historical review of landing gear development from
the 1950s. Back to the airport where 8th is trying to
outshout the motors of a 757. Off to the pilot of a
wwi style sea plane who says his name is Ian
Tindale and in the passenger seat behind him is
Maxwell Buchanan, the host of this new show. He
has a scarf with some kind of pastry on a plate flying
behind him in the wind and they are both worried
because it is not clear when and where they will
||//...where 8th is trying to outshout the motors of a 757//
...only to get sucked into the engine moments later? Please? Pretty please! :D
||OK, [pashute], you've got the job. When can you start?
||not sure if I've ever witnessed [8th] in a state of exitness.
||I would posit that all of the questions that might be asked
by the persistently periapoplectic viewers of this television
documentary could be answered by one of the following:
(c) lol people are irrational
It might be worthwhile expanding on (a)
and (b), just so people know how the world works, but
generally (c) will be Old News.
||What about (d), "limitations of the underlying science/technology ?" ... jetpacks etc. - can be built, can be made (relatively)* safe, not overly expensive - but limited by available hypergols, operational time etc.
||*Safer than trying to "fly" without one, anyway.
||Why did God make the Earth flat? It should be round.