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E-tap hydro levers. Kill them with fire.

I look to aviation for the lead in such matters. Aviation has the same penchant for weight-savings, albeit with an even keener focus on reliability and pragmatism. And there are many parallels in the evolutions of the two vehicles, such as the trend away from metallic construction toward composite polymers. Metal matrix composite materials actually were first created in secret by the defence industry, along with some advanced polymer construction techniques, and only declassified after the end of the Cold War (a substantial portion coming directly from the AH-64 Apache attack helicopter). And it is no mere coincidence that bicycle weights have plummeted since the collapse of Soviet Russia.

So I equate a bicycle's gear changing system with an aeroplane's flight control actuating system as both require the ability to make very smooth and subtle micro-adjustments. And nobody in general aviation is yet abandoning cables, pulleys and bell cranks in light aeroplane flight controls, just as Sir George Cayley first used in his functioning gliders in the mid-19th Century. Which tells me all I need know about electronic or hydraulic or steam or nukular operated gear changers.
 
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StyrbjornSterki said:
I look to aviation for the lead in such matters. Aviation has the same penchant for weight-savings, albeit with an even keener focus on reliability and pragmatism. And there are many parallels in the evolutions of the two vehicles, such as the trend away from metallic construction toward composite polymers. Metal matrix composite materials actually were first created in secret by the defence industry, along with some advanced polymer construction techniques, and only declassified after the end of the Cold War (a substantial portion coming directly from the AH-64 Apache attack helicopter). And it is no mere coincidence that bicycle weights have plummeted since the collapse of Soviet Russia.

So I equate a bicycle's gear changing system with an aeroplane's flight control actuating system as both require the ability to make very smooth and subtle micro-adjustments. And nobody in general aviation is yet abandoning cables, pulleys and bell cranks in light aeroplane flight controls, just as Sir George Cayley first used in his functioning gliders in the mid-19th Century. Which tells me all I need know about electronic or hydraulic or steam or nukular operated gear changers.

AND fly by wire, you aren't flying the flight surfaces, you are 'flying' the computer, inputs to it, and the computer decides how much deflection of the surface. So, like in the F-16, you can 'snatch' more than 9 gs but smoothly pulling, you can't really exceed 9gs. And when you get real slow, you can't put an input in that will stall the aircraft, computer won't let you.
 
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Bustedknuckle said:
AND fly by wire, you aren't flying the flight surfaces, you are 'flying' the computer, inputs to it, and the computer decides how much deflection of the surface. So, like in the F-16, you can 'snatch' more than 9 gs but smoothly pulling, you can't really exceed 9gs. And when you get real slow, you can't put an input in that will stall the aircraft, computer won't let you.
Fly-by-wire (or fly-by-light) are still far heavier than purely mechanical systems (cables, chains, push-pull tubes, pulleys, gears and bell cranks), and only become a viable alternative (from an engineer's perspective) if the a/c is in a performance category such that the force required to manipulate its control surfaces under worst-case conditions exceeds what a typical pilot might be capable of applying. Much the same way that the smaller (and lighter) Lotus automobiles (Elise, Exige) do not use power steering, but a three-tonne estate car couldn't live without it. Nor can an F1 car, which is lighter than most Lotii, but applies an aerodynamic load of several times its own weight to its tyres when at full chat. Until late in WWII, the control surfaces on all fighters and bombers, such as the Supermarine Spitfire and Avro Lancaster, were purely mechanical and un-boosted for the simple fact that that was 'adequate' to the job.

Clearly, dual-control shifting (via 'brifters') requires no such 'boosting' apart what is available through the mechanical advantage of the shifting 'levers,' else we cyclists all should have forearms like Popeye the Sailor Man from the effort.

cBDJg4H.png
 
Re: Re:

StyrbjornSterki said:
Bustedknuckle said:
AND fly by wire, you aren't flying the flight surfaces, you are 'flying' the computer, inputs to it, and the computer decides how much deflection of the surface. So, like in the F-16, you can 'snatch' more than 9 gs but smoothly pulling, you can't really exceed 9gs. And when you get real slow, you can't put an input in that will stall the aircraft, computer won't let you.
Fly-by-wire (or fly-by-light) are still far heavier than purely mechanical systems (cables, chains, push-pull tubes, pulleys, gears and bell cranks), and only become a viable alternative (from an engineer's perspective) if the a/c is in a performance category such that the force required to manipulate its control surfaces under worst-case conditions exceeds what a typical pilot might be capable of applying. Much the same way that the smaller (and lighter) Lotus automobiles (Elise, Exige) do not use power steering, but a three-tonne estate car couldn't live without it. Nor can an F1 car, which is lighter than most Lotii, but applies an aerodynamic load of several times its own weight to its tyres when at full chat. Until late in WWII, the control surfaces on all fighters and bombers, such as the Supermarine Spitfire and Avro Lancaster, were purely mechanical and un-boosted for the simple fact that that was 'adequate' to the job.

Clearly, dual-control shifting (via 'brifters') requires no such 'boosting' apart what is available through the mechanical action of the shifting 'levers,' else we cyclists all should have forearms like Popeye the Sailor Man from the effort.

cBDJg4H.png

Or fly by wire because the airframe, like the F-16, is by design, unstable. And no way to fly it without 'flying the computer'. But even the mechanical F-4 was boosted without any computers as were lots of early supersonic fighters. Some others, like the transonic MIG-15/17 had a really long control stick to be able to have enough leverage to actually turn with high Q speeds.

And 'boosted' front Ders shift far better under load(with uber stiff chainrings, like shimano) than strictly nechanical front Ders.