Short-field Performance Enhancement Program, 737

[KristianNorway]

Hey guys!

I'm looking into the short-field performance enhancement program for the 737, and I have some questions. I'm hoping for some well thought out answers:

"Slats are sealed for take-off to flap position 15 (compared to the current 10) to allow the wing to generate more lift at lower rotation angles."

- Sealed for T/O position. What does this mean? From what I've understood they remain at intermediate position ("sealed"?) until landing flaps (30/40).

"Two-position tailskid that extends an extra 127mm (5ins) for landing protection. This allows greater angles of attack to be safely flown thereby reducing Vref and hence landing distance."

- Why does this allow for greater angles of attack? Is it a certification question?

"Flap load relief function active from flap 10 or greater."

- Why does this reduce landing distance or shorten T/O-distance?

"Slats only travel to Full Ext when TE flaps are beyond 25 (compared to the current 5). Autoslat function available from flap 1 to 25."

- Again. Why does this reduce landing distance or shorten T/O-distance?


Thanks to all contributors:ok:

[Denti]

The two position tail skid is only an option within the SFP, you can or can not elect to have it while still being able to use the SFP performance data. For example all our new -800s are SFP equipped, however they have the normal tail skid.