couple of interesting illusions

[MarkColeman]

http://www.fazed.net/video/view/?id=736

'hollow head illusion' and below is the spinning silhouette illusion. The trick with the spinning silhouette is to look directly at the shadow of the dancers foot as it spins, and your brain sets the dancer spinning in the opposite direction. Can take a while for the illusion to work, took me about 5 minutes before my brain gave in.

http://www.moillusions.com/2007/06/spinning-sihouette-optical-illusion.html

http://www.pprune.org/forums/Spinning%20Sihouette%20Optical%20Illusion%20-%20Mighty%20Optical%20Illusionshttp://www.pprune.org/forums/Spinning%20Sihouette%20Optical%20Illusion%20-%20Mighty%20Optical%20Illusionshttp://www.moillusions.com/2007/06/spinning-sihouette-optical-illusion.htmlthese illusions are good reminders that things arent always as they seem, and its something we need to keep an open mind about in the cockpit.

[Basil]

Yes, there's quite a number in real life.
Landing westerly Frankfurt winter evening looked up and saw rush hour traffic moving diagonally on autobahn. Barbers' pole illusion of drift - back on instruments until past road.
Taking off or landing in snow blowing across - similar effect.
Turning visual left base at Ovda one evening with flat lighting from the setting sun perpendicular to the west facing hillside to the east - difficult to visually discern whether hillside very close and covered with small rocks or further away with bigger rocks. Needless to say it was the latter.
. . and then there's the old chestnut which gets the passengers worried - turning in hold with B747 1000' above or below.

[Basil]

Bit like the illusion at Ovda (Ah, we meet again D'Artagnan AKA 214 ;))

rubik,
. . can it be "Raising awareness of optical illusions on the flight deck."?
. . oh, yes, and its effect upon climate change (just to get the funding :rolleyes: )

[ChristiaanJ]

Another optical illusion involving a guy parking a Merc.I can see you don't live in France. The FR2 French TV does one like that almost every day, just before the news. Vey funny ones, too, most of the time.

[Avman]

and then there's the old chestnut which gets the passengers worried - turning in hold with B747 1000' above or below.

The more so the smaller the aircraft you're in. I'll always remember watching a BA B747 holding over Daventry in a left turn heading towards the G-159 I was in. It was, and crossed, 1000 below - but it sure didn't look like it would when first sighted.

[Brian Abraham]

Famous accident here http://www.prop-liners.com/midair.htm but probably little known about in todays professional circles. Scroll to the bottom for headings "Optical Illusions, Analysis and Conclusions".

[Basil]

TCAS is great!

but . . . some colleagues expect too much of it . .

e.g. you're at max alt, heavy and you get a "Climb! Climb now!" due a lighter jet below. :eek: