Boeing 717 Wings


#1

Why do the wings of the Boeing 717 have a flap that hangs down on the front of the wing?


#2

en.wikipedia.org/wiki/Leading_edge_slats


#3

Well golly gee. What will they think of next!


#4

Do slats come down with the first notch of flaps on all aircraft?(that have slats)


#5

Assuming you are talking about the 717-200, you should know that this aircraft is not a true Boeing design. It was originally made by McDonnell Douglas as the MD-95.

The 717 actually designed and built by Boeing is more commonly known as the C-135. 717 is the Boeing internal number.

en.wikipedia.org/wiki/Boeing_717
en.wikipedia.org/wiki/C-135_Stratolifter

Yea, I know this has nothing to do with the original question but I’ve always wondered why Boeing felt the need to change the designation of the MD-95.


#6

Interesting question, some slats retract at a certain airspeed, Saberliner
flightaware.com/photos/view/2417 … tes/page/2

At least that’s what I was told.


#7

The slats on the Sabre are very simple. The weight of the slat along with a spring working against the air loading is it. No cockpit control.


#8

Most slats on non-airliners are of the “automatic” type that are held in the stowed position solely by airflow. These were common on many aircraft during the biplane era (e.g. DH82 Tiger Moth), were found on the ME109 during WWII, the F-86 during the Korean conflict (and may have been complicit in the recent death of a good friend in his F-86), on the Navy’s A-4 Skyhawk, etc., etc.

They are an excellent way to assist the pilot by increasing lift and reducing the stall speed during landings without any need for manual operation. The one thing that needs to be guarded against is asymmetric deployment, e.g. when one slat deploys before the other or one slat extends and the other fails to deploy. A mechanical interconnection by cable or lever arm is often used to ensure uniform deployment and prevent an unstable aircraft. The ME-109 was infamous for lacking this interconnection, which often resulted in landing accidents among inexperienced pilots.

Nowadays what people see on modern jetliners are more likely to be some form of powered slats such as Krueger flaps or the slats on the Airbus A310.


#9

Thanks for the info.


#10

You’re welcome Will.