Landing a light plane: why is it hard?

Factual Questions
1

In iWoz, Steve Wozniak tells the story of a trip as a passenger in a “small plane” in the 1970s.

“So we flew back [to San Jose] after lunch – and there it was again, another one of those really, really bouncy landings. Again I just thought that’s how you land in small planes. There was a first bounce, then a second bounce that was pretty hard, then a scraping sound, and then it bounced, bounced, bounced, and bounced again for what seemed like the millionth time down the runway.”

When they got out, they saw that the prop was bent.

What do you suppose the pilot did wrong? Reduced power too much so he descended too fast? How else might he have messed up?

I guess landing most any plane is easy once you get the hang of it, assuming good weather and no crosswind and plenty long runway. Likely the weather was fine on Wozniak’s trip, so apparently the pilot didn’t have the hang of it. Is it that hard to get?

2

Sounds like porpoising (pilot-induced oscillation) to me. Here’s an AI overview, since I’m working at the moment:

What is Porpoising?

Porpoising occurs during landing when an aircraft bounces on the runway, typically starting with a nose-first impact. This results in a cycle of repeated bounces, where the aircraft alternates between rising and falling, similar to how a porpoise moves through water. This behavior can be initiated by factors such as excessive approach speed or improper flare technique during landing.

Boldmethod**+1**

Causes of Porpoising

  1. Excessive Approach Speed: If the aircraft is too fast during the final approach, it may float above the runway instead of settling down smoothly. Pilots may instinctively push the nose down to correct this, leading to a nose-first landing.

    1

  2. Improper Flare Technique: A poor flare can cause the aircraft to touch down nose-first, which compresses the main gear and causes the tail to drop. This increases the angle of attack, generating more lift and causing the aircraft to bounce back into the air.

    2

  3. Pilot-Induced Oscillations: These occur when a pilot makes overcorrections in response to the aircraft’s movements, leading to a cycle of increasing bounces.

It would be an easy way to bend the prop.

3

In my limited experience flying a small plane (Piper Cherokee) landing a small plane is not hard at all. After just a few dozen landings, I was even able to do smooth crosswind landings (which are quite different in a small plane than in a big jet). A bumpy landing sounds like pilot error, or perhaps a sudden unexpected wind gust.

4

I porpised maybe once. Generally the trick is to come in nose down (obviously, you are flying downward) then pull the nose up and flare and try to keep the plane level to bleed off speed. Obviously you want to be well above stall speed until you are just about ground level. Then, as the plane slows you keep pulling the nose up.

Stall is where the wings no longer make enough lift to keep flying. Think of it like the water-skier who is done and lets go of the rope - their skis get progressively more nose up as they slow, until that is not enough momentum and they sink.

Flare (level off) too late, the nose hits the ground; pull up a bit too hard and instead of level, you go up - and you don’t want to be 20 feet up when the speed falls to stall speed. So it’s a skill to move the controls back and forth to keep the plane low but above the ground.

In that OP episode, sounds like the pilot flared a little late, hit the ground, the nose bounces upward so the plane tilts up and starts to go up - the pilot overreacts to push the nose down too far, to stay close to the ground, and overcorrects and has the same experience. After all, the landing gear are obviously “springy” to absorb the landing, so if it’s too hard a landing that will help provide the bounce.

5

No argument with that, but it somehow makes it sound harder than it really is. Flaring at just the right time quickly becomes ingrained and natural. It helps that small planes are so responsive. With a heavy airliner I think you have to start the flare based on altitude, at something like 30 feet above the runway.