They are not slats but are kreuger flaps. They do not extend downward from the wing like other flaps. They fold in/out. IN they are flush with the underside of the wing.

I will have to check the manual to see when they extend but I believe they come out with the initial flap setting of 1. The 727 had 1, 2, 5, 10, 15, 25, 30 and 40. Later 40 was blocked off for State III Noise and I understand 30 is also now blocked off on most. (FWIW, on the -135 the max flaps was 50deg

http://farm4.static.flickr.com/3129/...cf0622fc3e.jpg

That is absolutely the most bizarre thing I think I've seen all day. I saw those things extended on that 727 that sits at CLT, and I just thought the wing was broken or something. I feel really stupid now, I should probably know that, but I've never heard of them before.

So the rest of the wing has regular slats right? That's how it looked to me. If that's the case, do you have any idea why regular slats just wouldn't work for the entire wing?

And forgive me, but I don't quite understand what you mean about the reason behind blocking flaps 40 and 30. But that's A LOT of flap settings. By comparison, how many do, oh say... B757/767 have?

I've never seen Flaps 1 or 10 in 15 years on the 727. Some had 20 though. You got the #2, 3, 6 and 7 slats with flaps 2 and all the rest of the slats and all the Kruegers with flaps 5.

Blocking 40 meant you'd use less thrust on approach and therefore be quieter coming in. There's one hush kit that has you landing with flaps 25 but I'd say most folks still land "30, 30, green light."

And all that stuff is anti iced after it unfolds except the #1 and 6 Kruegers with bleed air. All sorts of telescoping and twisting tubes.

My mistake. Confusing 737 with 727.. and don't get me started on the MD-80 with 'dial-a-flap'. (..shoulda checked the book.. shoulda.)

767/757 has 1, 5, 15, 20, 25, 30 - which roughly correspond to the number of degrees deflection on the 757 (and if memory serves the 767's "Flaps 30" is more like 40 degrees).

The blocking off of Flaps 40 you speak of is done with a bolt (I've looked at a few -200Adv cockpits before scrapping)...a few twists and if you need Flaps 40, you can get it. (You can also still select it with the alternate flaps system.) Landing with 25 seems to limit the capability of the airplane, although in the stacks of stuff I have, I have no ODM, so couldn't tell you for sure.

This sounds like the most complicated wing ever designed. Was it prone to Mx issues?

Interesting. I didn't realize the 727 was THAT loud. I'm still wondering why they put these weird Krugers on there to begin with. I'm going to go try and research this.

Thanks for all the input, I like stuff like this. I enjoy learning new things. However, it makes me a bit jealous that I've never had nor probably will have the opportunity to fly one. I'd love to fly that, AND the DC-9. Call me crazy, but if NW called me up and said I could fly the 9 or the bus, I'd take the 9 every day.

Good Job Boeing
 

Nope. Truly well designed and thought out. Maintenance loved the aircraft for it's reliablity.

It was the first "true" swept wing turbo-jet aircraft and may have been the best of all. If fuel issues hadn't shortened it's shelf life, you would still see them flying today.

Twin Wasp, you're right on ! "30,30 Green light" Now, just roll it on !!

I'm getting teary eyes Mates, G'Day:)

I never have flown in or on a 727, but have experience in the Level-A and -C sims at Purdue. The 30,30, Green Light callout comes into my memory also! I loved flying that sim and hoped one day I could fly one in real life, but as time passes so do my chances(and plus my current job I don't see myself leaving). I do love watching the various operators that still use them fly in and out on occasion.

Eastern must have done it with some amusement but they referred to their 727s as "WhisperJets". The JT8D did anything but whisper, especially the JT8D-17s which sounded as if they were about to come apart at takeoff thrust.. a cross between a scream and a roar.

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Didn't fly the -9 but did fly the -80 and it clearly demonstrated the difference in philosophies between Boeing and McDoug. But like the 727, the -80 (and more so the DC-9) was a hands on airplane. The very high extension speeds (280 for initial flap extension) were very useful. Although I never did it, I know some -9 drivers who gleefully claimed to hit the outer marker clean and at 250kts and have to spool up for landing.

One guy summed the -9 up by saying, "It is like a baseball bat. Nothing sophisticated. Extremely useful, simple to use and as for maintenance, very little. It works or its broken."

I think they were referring to the noise level in the cabin...which wasn't a whisper, but was much improved except in back between the -8Ds. And in front, come to think of it.

When I was a wee lad, when Stage 3 was the new hot thing that people were just getting around to complying with, the family house was on the extended centerline of the 34s at Seattle. There was little question as to when a 727 was coming in. Even hush kitted, the airplane is noisy.