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Heh!  As you know, a CH-53 is a monster of a helicopter.
Most of my time was at the opposite end of the spectrum--OH-58 Scouts (very similar to a Bell Jet Ranger), UH-1 Hueys (in flight school and during my year as a "staff aviator" in Korea, and AH-64 Apaches.  The Apache was the biggest, and IIRC, we usually flew it weighing about 16,000 lbs at takeoff.  The CH-53E has a max gross weight of 73,500 lbs.  Going from an OH-58 to that would be like going from an Mazda Miata to a Kenworth hauling two trailers.

What I found interesting is that the CH-53 is one of the fastest helicopters in existence as well, because it's a 7-blade rotor. 

In forward flight, the faster you go the closer you get to rotors on the trailing side (moving opposite direction of travel) stalling out while the rotors on the leading side being the only ones that can continue producing lift. The 53, with 7 blades, can mitigate that at a high airspeed better than perhaps an Apache with only two rotor blades.  

At least that's how I understand it--feel free to correct me if it's bullsh!t ;-) 

Automation is really amazing today.  That could be the barrier to having flying cars.  There are others of course.

The primary, and by FAR the most important, is simple energy efficiency.

A car on the road requires no application of energy to keep from falling into the earth. The mass of the car pushes it into the ground and the planet pushes back, and all is balanced. Turn off the engine, and nothing happens. The energy of the car can thus be used entirely for propulsion.

A car in the air cannot remain aloft without the addition of power. The air doesn't provide meaningful resistance to the force of gravity. Turn off the engine, and it plummets until it reaches stasis (where it hits the ground and the force of gravity is balanced by the earth). Thus, the energy of the car must be used for both proportion and lift. 

We will not have flying cars until and unless we find some zero-cost or minimal-cost energy source such that ALL that additional energy to create lift is free or basically free. 

I don't see even theoretical sources of energy like this on the horizon.

The flying Delorean could never happen in the post 911 era. 

Probably for the better, as a mere fender bender could result it two cars just dropping down into the city. 

The other problem with a 172 is that while it has four seats, it you put 4 200 pounders in them, you probably are over the weight limit, not to mention luggage.  You can compensate by loading less fuel if you wish.  Now, those engines are archaic, magnetos, two spark plugs per cylinder, ours were carbureated, the newer ones have FI and electronic ignition at least.  They are also large boxer 4 cylinder engines with two valves per cylinder burning rather expensive 100 LL av gas.  One can get better more efficient engines.

BUT, the purpose of the wing is to convert drag into lift, which is to your point.  You have to have lift, and it comes from drag, in a piston engined plane.

A Mooney is a nicer plane, but far more expensive.  A car-plane duo will always be more effective I think.

Mooneys are nice planes, really nice.  $$$$  And 237 KIAS is pretty fast and you pay for that speed.  You can't do that on the ground very well.  That is 273 mph.

I contracted a professor at U Akron to consult with us and he flew down in a King Air twin, and that afternoon he let me "fly" it a bit.  I got him lined up when we came back with Blue Ask airport but was WAY too high.  A Cessna 172 will float a good bit, he cut power and we dropped like a rock.

The way to lose altitude in a Cessna is either to slip it, turn it sideways, or drop the flaps and point the nose down, but not both at the same time, he just cut power.  Twins are very expensive to operate, and you need twin engine cert.  This is why airlines like Navy aviators over AF pilots.

Do you know why they use knots for ships and planes?

Do you know why they use knots for ships and planes?

No, but wikipedia did lol...

What I found interesting is that the CH-53 is one of the fastest helicopters in existence as well, because it's a 7-blade rotor.

In forward flight, the faster you go the closer you get to rotors on the trailing side (moving opposite direction of travel) stalling out while the rotors on the leading side being the only ones that can continue producing lift. The 53, with 7 blades, can mitigate that at a high airspeed better than perhaps an Apache with only two rotor blades. 

At least that's how I understand it--feel free to correct me if it's bullsh!t ;-)

OK, here we go.
"B.S." is not quite right, as I will try to explain.
Retreating blade stall is the limiting factor on airspeed for a helicopter.
As you noted, the blade as it retreats has less airspeed.  In fact, as soon as you start directional flight, the root of the retreating blade stops producing lift.  The compensation is that the flight controls are rigged to increase the pitch of the retreating blade as the cyclic is pushed away from neutral.  (I'll use "forward" as the example, but the same thing happens to the rotor disc if you are flying sideways or rearward.  BTW, I left out the term "feathering" in my lengthy post on this subject.  That refers to the rotor blades changing pitch.)
So, the faster you go, the further out on the retreating blade there is no lift being produced, requiring ever more pitch increase to produce the same amount of the lift that the advancing blade produces, and eventually there will not be enough and the helicopter will go out of control.  The highest airspeed that the helicopter can fly without this happening (minus a bit for a safety cushion) is Vne, Velocity Not to Exceed.
So, you know all that, more or less.
But that happens whether you have 1 blade (plus a counterweight), 2 blades (like a Huey), 3 blades (like Sikorskys of the 1950s), 4 blades (like an Apache) 5 blades (like the pre-"E" model CH-53s, or the 7 blades of a CH-53E.  The retreating side of the rotor disc is still working with high blade angles of attack to produce enough lift to balance the lift being produced by the advancing side.
What I think the advantage of having lots of blades is that they smooth out the felt impulses of each blade going from high airspeed/low AoA to low airspeed/high AOA.  I suspect also is that the blades on the CH-53 are designed to function well at high AoA.
The real fix is to have co-axial, counter-rotating rotors on the same rotor shaft.  That way you have advancing sides and retreating sides cancelling each other out.

OK, here we go.
"B.S." is not quite right, as I will try to explain.
Retreating blade stall is the limiting factor on airspeed for a helicopter.
As you noted, the blade as it retreats has less airspeed.  In fact, as soon as you start directional flight, the root of the retreating blade stops producing lift.  The compensation is that the flight controls are rigged to increase the pitch of the retreating blade as the cyclic is pushed away from neutral.  (I'll use "forward" as the example, but the same thing happens to the rotor disc if you are flying sideways or rearward.  BTW, I left out the term "feathering" in my lengthy post on this subject.  That refers to the rotor blades changing pitch.)
So, the faster you go, the further out on the retreating blade there is no lift being produced, requiring ever more pitch increase to produce the same amount of the lift that the advancing blade produces, and eventually there will not be enough and the helicopter will go out of control.  The highest airspeed that the helicopter can fly without this happening (minus a bit for a safety cushion) is Vne, Velocity Not to Exceed.
So, you know all that, more or less.
But that happens whether you have 1 blade (plus a counterweight), 2 blades (like a Huey), 3 blades (like Sikorskys of the 1950s), 4 blades (like an Apache) 5 blades (like the pre-"E" model CH-53s, or the 7 blades of a CH-53E.  The retreating side of the rotor disc is still working with high blade angles of attack to produce enough lift to balance the lift being produced by the advancing side.
What I think the advantage of having lots of blades is that they smooth out the felt impulses of each blade going from high airspeed/low AoA to low airspeed/high AOA.  I suspect also is that the blades on the CH-53 are designed to function well at high AoA.
The real fix is to have co-axial, counter-rotating rotors on the same rotor shaft.  That way you have advancing sides and retreating sides cancelling each other out.

Betarho:

I submitted both my previous essays on this subject under severe time constraints.  Here's what I left out, and I think it's the best explanation for the CH-53E's speed.  It's the most important reason that the UH-60 Black Hawk is faster than the AH-64.  The main rotor shaft is tilted forward.  That means the helicopter hangs tail low in a hover but is relatively level in forward flight.  The AH-64, by contrast, has a main rotor shaft that is perpendicular to the long axis of the fuselage.  It is level at hover, but flies nose down, creating more drag, in forward flight.  Not coincidentally, the UH-60 and the CH-53 are both Sikorsky products.  Also not coincidentally, they both have tail rotors that have their thrust vectors tilted upward so as to ameliorate the tail-down condition at a hover.
I don't know if it was the "E" model or not, but when the Marines started doing helicopter air-to-air combat training in the late 1980s (IIRC), they used the CH-53 to simulate the Soviet Mi-24 "Hind" attack helicopter as the adversary aircraft.