lights on the sides of the seats
 

I noticed on some aircraft, there is a small blue led light on the side of the first class seats. Occasionally, one of them is lit. What is it for? I even got up the nerve to ask one of the FA's - she had never noticed it before, and none of the other FA's had an idea what it was either.

What aircraft?

I've seen some of the fancier electric BE seats (I forget which ones), that have a light (I forget what color), that seem to indicate to the FAs whether or not the seat is fully upright for takeoff and landing, but you say - First Class seats. I guess you didn't, or can''t taka pic??

Also, I'm not really sure why you'd need nerve to ask a FA that!

I LUV to talk to the FAs whenever possible - - including about FlyerTalk! Anyway, once, I remember being on an A320. The seat pocket emergency cards say - A320-SR. I asked what "SR" means. They didn't know - - and neither did the pilots!!! :D

My ed-ji-kayted guess is A320-Standard Range, compared to ER (extended range) and LR (long range).

Any thoughts?

DYKWIA sensor lights to warn the FAs.

That's why they weren't allowed to tell you what they were.

Was yours lit up?:D

The B777 BE seats have a green light to indicate the seat is in the up right position for takeoff/landing. There is also a blue light indicating the in seat power outlet is in use.

On the refurb'ed 767's (with lie flats) there is a light that seems to indicate whether your seat belt is fastened.

Those lights have the same function as the ones found on the 777s: they indicate a seat in the takeoff/landing/taxi position.

Those are Boeing designations. For Airbus, SR means "slide/raft" and is used to denote over water equipment.

Thanx for solving my age-old question that even the pilots didn't know, and I never realized those designations were unique to Boeing! :)

FlyerTalk is priceless, isn't it? :D

Small blue LED lit indicates that power is being used by the seat - i.e. something is plugged into the seat outlet.

Mostly domestic birds that have power up front have this feature. Plus something in and see it light up. Unplug and the light goes out...

ET had a light in his belly. I don't know if Richard Dreyfuss ever got over it.

lights on the sides of the seats
 

Lights on the side of hear seat and diamonds on the soles of her shoes.

This is what I've been told. I would expect that the other aircraft that have been reconfigured with flat beds might have similar lights, for example the 767-400s, 747s, and redone 767-300s, but I haven't observed the lights on those aircraft.

If the OP really means (domestic) FC seats, I think I've seen some amber lights in the middle of the outside of the metal plate below the aisle armrest. These light up with the escape path lighting, so they're some sort of emergency lights. There are also lights that indicate that someone in the row has used the FA call button, but that little light is usually overhead, on the aisle side of the controls for lights, in aircraft that don't have the light and call button functions in the armrest.

ET had a light in his finger.

Dreyfuss was in Close Encounters.

It's a cell phone detector. Lights up when phone is powered ON.