This post is long, but I'm a pilot and this is one of my better subject areas.
I'm not sure it's much easier to put a helo down on a pitching deck. It's still pitching. I suppose the best way would be to bring it in such that the deck's top-of-travel is just under the skids. Wait for it to reach bottom-of-travel and start heading back up, and as it nears top-of-travel (but isn't quite there yet), smoothly reduce the collective to zero and hope that you drop to the deck before it begins moving downward again. The skids will probably probably
not hit the deck squarely because the angle of the deck changes with how high or low it's heaving, so you'd have to hope for the best. It might "mousetrap" (land on one side, with the downward velocity causing the other side to slam down). I saw a video of a helicopter trying to land on a pitching deck, and it wound up in the drink with a shattered rotor!
Airplanes are different. Landing is the hardest thing a new student pilot has to learn. It's harder than taking off, and
way harder than flying level. The airplane's angle and airspeed both have to be managed such that the airplane is at the right speed when it reaches a point near the beginning of the runway, and a dozen or so feet above it. Pointing the airplane at the approach end of the runway is pretty easy - it's managing the
speed that requires careful attention. If you just point the nose at the approach end of the runway and chop the throttle, you'll get there, but you'll be going WAY too fast when you arrive. When you arrive near the touchdown zone,
ground effect complicates matters by greatly increasing the amount of lift the airplane makes for a given airspeed. (Interestingly, some vehicles fly
exclusively in ground effect. They can't fly very high, but they can reach their destination using
much less fuel, and carry their cargo with
much smaller engines, than would be required of an airplane that flies at traditional altitudes.) Ground effect is also used by pilots who are taking off, but that's another story.
If the requirements to deal with airspeed and ground effect aren't enough, there's another issue: The wind. It can get
treacherous when you get close to the ground. It has to go around trees and buildings, crest hills, drop down into and climb out of valleys, etc. It can get really turbulent at the worst moments. There can be unexpected shear to blow you off course. Worse yet, there are times when rapidly changing wind speed/direction can cause the airplane to either balloon, or to sink. It's also necessary to manage the rudder, crabbing into whatever crosswind might be blowing across the runway.
The right way to land - the way every pilot is taught with
painstaking care - is to do something that's initially counter-intuitive: use pitch to control airspeed instead of altitude, and use engine power to control altitude instead of airspeed. Lift is greater with the flaps down, as they are during landing. As lift is a function of airspeed, changing the throttle even slightly can produce a significant change in the airplane's vertical speed (lift). In order to keep the airspeed (forward velocity relative to the local wind) from running away, we pull back on the stick (or yoke) in order to nose the airplane up. It would climb if it was going faster, but since it's fairly close to stall speed, it doesn't climb. What it
does do is modulate the amount of drag on the airplane. Higher pitch angle = more drag. So, your throttle controls your vertical speed, and your pitch makes sure your airspeed doesn't get out of control.
In a bugsmasher (piston-engined airplane like a Cessna 172), it's sufficient to use a little pitch and low to moderate throttle to control the landing profile. A more slippery prop plane (like a Mooney) requires more pitch and/or less throttle, because it just doesn't have as much drag to contend with. However, in something with a turbine (jet engine with or without a bypass fan, as well as turboprop), they use relatively high pitch and throttle. This is because turbines take much longer to spool up to full power than piston engines. If you cram the throttle in a 172, it will go from 1000RPM to 2400RPM (or whatever the redline is) in less than a second. In a turbine aircraft, idle to full power could easily take five or six seconds. When landing, you want all the reserve power you can have at a moment's notice in case you have to go around and try again. So, they fly with the throttle at some moderately high setting, and they pull the nose up enough that the drag keeps the speed from running away. You can land a bugsmasher like this as well, at the "back end of the power curve," but it feels precarious (wobbly, like it might stall and roll precipitously to one side). It's also a bit shaky - flying at a high angle of attack tends to make the air quite turbulent, and then it batters roughly against the extended flaps. I've only ever flown bugsmashers in real life, and I prefer to land them with moderately low pitch and power. Turbine aircraft are designed so that they don't get wobbly and shaky at the AOA required to land them properly.
There is something very useful that can help a pilot manage their airspeed and altitude. Many runways have visual indicators such as the
VASI and
PAPI. These are placed near the approach end of the runway. The lights are set up so that if you view them from above a certain angle, they appear white; but from below that angle, they appear red. They do this with baffles and color gels. With VASI, if you're below the glidepath you see red over red; on glidepath, white over red; above glidepath, white over white. With PAPI, you see two red and two white when you're on glidepath. As you go above or below, more of the lights turn white or red. On a carrier, they have some kind of Fresnel system called a "meatball" that puts the colors into a single light. I don't know if they use white/red. I think it might be green/red, or green/white/red. It has been over a decade since I played Janes' F-18 combat sim. (Yes, I did lots of carrier approaches. Fun, but taxing!)
The VASI/PAPI/meatball is angled such that you see "correct" (white over red, or two white and two red, or however the meatball works) when you're approaching from the right altitude, no matter how far away you are. If you're flying towards the runway along its centerline and you see "correct", you know that's the time to begin your descent. If on the runway centerline and you see "too low" or "too high", you adjust accordingly. You manage pitch and power (for airspeed and altitude) and rudder (for crosswind correction). You stabilize the approach as early as possible - you don't want to be hunting for the right pitch and power setting, and you can't let the crosswind blow you off the runway's centerline. Correcting early is far easier than correcting later, which is why you stabilize miles out from the touchdown zone. If the wind changes relative to the airplane, already being stabilized makes it easy to correct. The wind MAY get squirrely close to the touchdown zone - again, being stabilized beforehand is a big help.
Ultimately, the airplane is going to be pushed left, right, up, and down - and be accelerated and decelerated - by the changing local wind. This moment you will be pushed to the left of the runway. The next, you will be pushed up and right. After that, something different may happen. It's easy to over-correct and do a lot of "chasing." (My primary airport is surrounded by all kinds of hills and valleys and the wind can get really annoying, so I've had plenty of opportunity to practice and figure it out.) The pilot has to be patient and watch what the airplane does over many seconds, so that they can average it out and get the forward vector they actually want. For a carrier landing, some more averaging is required. The deck will be changing its elevation and surface angle constantly, so the pilot has to watch it and figure out its range. Then, the pilot can shoot for some useful "average" elevation and deck angle. The pitching is not something you want to chase from far out; it's completely irrelevant until you're almost there, and trying to correct for it continuously will only introduce harmful oscillations into the approach, so until you've almost arrived at the carrier, you only care about the average.
I'm not sure what actual carrier pilots do to transition from "approaching the average" to "touching down at exactly the right elevation and deck angle". I had quite a few "bolters" when I was flying the F-18 sim.
