Beach Sand "Landings"
One time my student and I landed on the ocean beach sand so we could not only take a break from flying maneuvers in our rented SkyHawk but, also get her caught up on some ground instruction in my tent pitched under its wing in the sand. Our ground lesson was progressing nicely, being surrounded by fresh, salty seabreeze and summer sunshine and the wet sand was getting warm as the tide continued to rise. After awhile, a guy came walking towards our netting wall which was facing the blue green and white breakers in full view -somehow we hadn't even heard the C150 flying overhead for landing.
"Do you know where I can get a tow?"
"What's the problem?"
"Had a hard landing and my nose gear's collapsed.... I don't know what happened....."
"See that five foot layer of water vapor coming off the warming sand like steam fog?" I asked.
"That's providing the haze illusion, making your landing surface look farther away than it really is since the human eye automatically focuses on infinity in haze. Were you using full flaps?"
"I always use 20 degrees of flaps on landing so if I forget to retract them on a go-around my plane will still climb."
"Your operator's manual calls for FULL FLAPS for a soft field landing."
"I've always used 20 degrees...."
It is of course always the PIC's responsibility to make sure to retract flaps as needed for any go-around or other reason. Getting into the one-size-fits-all habit is often not at all good for flying. If the PIC had been really on top of his landing while in haze effect illusion, probably the 20 degrees wouldn't have mattered enough to descend so fast as to collapse the gear but, the combination of the two factors at the same time was not so forgiving.
We resumed our ground activities at an increased rate to make up for the lost time and about a half hour later, saw the PIC riding on his bent plane's horizontal stabilizer to teeter-totter the gnarled nosewheel up off the sand while a small 4X4 towed him along the long mile of ground foggy sand to the road access, for later trailering back to his FBO.
A few years before that, I looked at a VERY sandy SkyLane on a trailer at our club/FBO with it's wings off and the nose strut and wheel jammed up through the engine compartment. It had "landed" on the same beach with 4 souls on board. I don't know what landing configuration was used or the surface visability or illusions state was but, SkyLane's are always nose heavy on landing and require extra diligence on soft surfaces of any kind for safe touch downs.
The many different haze illusions and, the illusion-of-haze illusions, are particularly prevalent in the seaplane environment both on the waters and the beaches or runways. A whole paper could be written on their often deadly variants alone.