Is there something particularly challenging about the sixties? Nothing much different than equipment built in the fifties...and really not a whole lot different than what came out of the 40's. Pistons to turboprops, but working the panel on one isn't much different than another...the basics of the respective systems don't change much. The 70's didn't bring a whole lot of change either.
Probably the most challenging airplane I've flown wasn't fast, or particularly high performance...or necessarily hard to fly. I spent his last summer in a polish airplane, and like some airplanes of it's type or class, it's not really very stable. Not dramatically so, nothing unmanagable, but just enough to keep you awake.
The rudder movement in the airplane never stops...always working the rudders. It's short coupled and takes a lot of rudder. Get in behind a ridge with some good solid wind coming over the top, and full control deflection with aileron and rudder wouldn't stop it from rolling over. Come into a tight canyon and suddenly find that there is no climb performance, and that gets your attention. Not difficult, but it did posess a certain challenge.
It would go from cruise speed to stall buffet when crossing a ridge with windshear and rotors in a second...and being a turboprop it had no quick fix on the power. The nose on these types of airplanes is long enough that it's a toss up in a strong crosswind on the correction: sometimes the moment of a gust on the nose is stronger than that on the vertical stab. The airplane can yaw into or away from the wind. Like many conventional gear, any significant braking will put it on it's nose, and reverse thrust on landing can result in a fast loss of control if not careful.
Most notable was ferrying the airplane home at the end of the season. Half way, decided that nature was calling and it was time to answer. Because of the cockpit layout, some degree of gynastics were required, and I quickly found that trying to stand or lean resulted in a turn in that direction. Lean forward, the airplane dives, lean left, the airplane keeps going left. It doesnt' stop, either, unless it's recovered.
Other higher performance equipment is less stable and goes south faster, but not without assistance at low level and close to terrain. It was a refreshing change of pace from the regular job, getting to fly something that requires a little attention for a change.
Still, in terms of difficulty, one can't say that a J-3 is easier to fly than a Bonanza, or visa versa. One might have learned to fly in a V-35 and be quite proficient. One might then get into a cub and kill one's self. There are no complex systems and no great performance issues with the cub. It's simple, straightforward, and easy. It can also eat your lunch.
Likewise, one who has experience in an arrow may find himself in a world or hurt when faced with the lesser performance of a cherokee 140. It's all relative.
A flight instructor who has flown nothing but apaches and Cessna 172's may have a short, steep learning curve when jumping into the right seat of a lear when changing to a 135 job. However, in short order, it will all become clear. It's not nearly as big a leap as the instructor might have thought. Let him go a year in the lear, and then put him back in a cessna 150. He may not be able to land it at less than 90 knots, or use less than 3,000' of runway doing it. Suddenly the 150 is harder than the lear.
Which is more difficult? You tell me. I haven't a clue. It's just an airplane. I fly them, and if I can do it, believe me, anybody can. If I can do it, then it's certainly not difficult.
Change the characteristics of the airplane. A heavy Cessna 207 in terrain will be a lot more challenging to fly than a light Cessna 210 operating from a paved long runway. The way in which it's operated make a huge difference. Most any airplane could be flown by gradeschool kids if left squarely within the limits of it's operating envelope. Drag it out near the edges or begin to work the airplane, and that's another matter entirely.
There's nothing like coming up on a set of powerlines and debating your ability to go over them, and the wisdom of going under them, then making a decision, acting, and seeing it happen in just under a second and a half. A very clarifying moment.
Conversely, flying an airplane in instrument conditions in weather, on a complex approach proceedure may be increadibly challenging. Shut down an engine and fail a system, then do it single pilot, and a very easy airplane to fly just became a monster. Take a benign airplane under simple conditions and just go to partial panel...something everyone trains to do, but few ever do in real life...and it can and often does become a killer.
Then again, a Cessna 172P will hurt you just as badly, and kill you just as dead as a Lear25D...which is more difficult? Neither. It's all very relative. Relative to your experience, the conditions, the mission, the loading and configuration, and many other factors. After all, it's just an airplane, and it's been designed to be user friendly. The question is, how friendly are you??
