This one is a very, very, very good piece from the Pythoneers. The Norwegian KLM-team also made a poor version of it for Norwegian National Broadcasting, but... well... It was poor in comparison. Enjoy.
The Airline Pilots Sketch

by John Cleese & Graham Chapman

Transcribed from the video:
"John Cleese on How To Irritate People"

The Cast   Captain:       John Cleese
           First Officer: Graham Chapman
           Steward:       Michael Palin

(The sketch opens in an aeroplane cockpit.
 The Captain and the First Officer are whistling idly.
 They are obviously very bored.)

C:  I spy with my little eye something beginning with S.
FO: Sky.
C:  Mm-hm.
FO  I spy with my little eye something beginning with C.
C:  Cloud.
FO: Yeah.
    Oh God, I'm so bored.
C:  I'm fed up with that game.  Let's play another game.
    I know what..
FO: What?

(The Captain picks up a microphone.)

C:  (over intercom) "Hello, this is your Captain speaking.
    There is absolutely no cause for concern."
    That'll get them thinking.

(The First Officer reaches for the microphone.)

C:  No, no, no, no.  Not yet, not yet.  Let it sink in.
    They'll be thinking, er, 'What is there no cause for alarm
    about?  Are the wings on fire?'
    (over intercom)  "The wings are not on fire."
    Now they're thinking, er, 'why should he say that?'
    So we say...

(The Steward enters.)

FO: Oh, how are we doing?
S:  (looks down the aisle) They've stopped eating;
    Looking a bit worried...
C:  Good.
S:  Hang on, one of them is going to the washroom.
C:  Is he there yet?
S:  He's just closing the door... NOW!
C:  One... Two... Three..
FO: (over intercom) "Please return to your seats and fasten your
    seat-belts immediately."
S:  Yes... here he comes, going up the aisle like the clappers.
    I'll do the worried walk now.

(He leaves.)

FO: Right. Safety regulations.
C:  (agreeing) Safety regulations.
FO: (over intercom) "Please listen carefully.  I want you, I want
    to remind you of some of the safety regulations.
    In the case of emergency it is vitally important to..."

(The Captain makes a radio-static type noise.)

FO: "as the warning buzzer sounds."
C:  "Bzzzz"

(They both laugh.)

C:  Oh, that's got them rattled.
S:  (enters) Great, great! (exit)

C:  Hey, I've got an idea!
    "Hello, you will find your life-jackets under your seats."
FO: No, they're on the racks.
C:  Sh, shh, let them scrabble a bit.
    "I'm sorry, you will ind them on the racks above your heads."
FO: Aaah!
S:  (back again) Great, great, that was marvellous!
FO: Right.  Gobbledegook.
C:  Oh, yes.
FO  "The scransons above your heads are now ready to flange.
    Please unfasten your safety belts and press the emergency
    photoscamps on the back of the seats in front of you."
S:  (looks out) Marvellous, milling about, climbing over the seats.
FO: "Please find the emergency sprill in the washroom at the back 
    and release it..."
C:  "but do not unfasten your safety belts."
S:  That got them back to their seats.
FO: "The emergency sprill MUST be released..."
C:  "but do not leave your seats."
FO: "Do not panic."
C:  "Tea will now be served."
FO: "Inflate your life-jackets"
C:  "and extinguish all cigarettes."
FO: "Please remove the luggage from the racks above your heads and
    place it on the racks on the other side of the aircraft."
C:  "Except for hand luggage..."
FO: "which you should sit on."

(They are in fits of laughter.)

C:  Now have a look.
S:  (looks) Hang on... hang on... they've all jumped out!

(They laugh, pointing downwards and looking out of the windows.
 After a while the laughter dies away.
 There is a lengthy pause.)

C:  You know, I wouldn't be surprised if there was some trouble
    about this.

(They burst out laughing again.  The sketch ends.)