AC_B777 From Canada, joined Aug 2000, 809 posts, RR: 13 Posted (12 years 4 months 2 weeks 4 days 17 hours ago) and read 1143 times:
I was looking at the picture below and was wondering about the Kruger flap configuration set for landing.
This KLM 744 has landed with only the outboard Kruger slats deployed. Why would'nt the mid and in-board sections be deployed?
Obviously the a/c is still travelling fairly fast as shown by the spray, and too early to retract the flaps.
What kind of performance would the 744 have in this configuration? Is this a normal practice for KLM or any airlines? I ask because I have never seen a plane land or takeoff with only a partial flap/slat setting.
Cx flyboy From Hong Kong, joined Dec 1999, 6605 posts, RR: 55
Reply 3, posted (12 years 4 months 2 weeks 4 days 15 hours ago) and read 1071 times:
That is correct, this can be seen inside the cockpit as an indication. Normally the little flap indicator sign is marked 25 or 30 (As appropriate) and is in green, indicating the flaps are in position. Select reverse on the ground and the indication will turn magenta coloured, indicated not all flap groups are in the right position they should be. When reverse is deselected, the indication turns green again, as the leading edge extends again (Only for you to put them back in again!).
Mr.BA From Singapore, joined Sep 2000, 3423 posts, RR: 22
Reply 5, posted (12 years 4 months 2 weeks 4 days 11 hours ago) and read 1014 times:
Sorry I didn't really get you there. You mean it's normal for the middle slats and inboard slats not to extend and only to extend after retracting reverse thrust on the ground? (Flaps 25/30 both have slats extended?) Wonder why the slats don't extend? Thanks a lot for the further explanation.
AJ From Australia, joined Nov 1999, 2392 posts, RR: 24
Reply 6, posted (12 years 4 months 2 weeks 4 days 6 hours ago) and read 992 times:
The aircraft has Flap 25 or 30 set for landing, including all leading edge flaps extended. The flight deck indication is a green line at 25 or 30. When the reverse thrust levers are raised to the interlock the inboard and midspan leading edge flaps retract whilst the engine reverser system is activated, giving a magenta line on the flap indicator (Boeing code for commanded but not yet reached). After the reversers are stowed the leading edge flaps redeploy giving a green indication.
AC_B777 From Canada, joined Aug 2000, 809 posts, RR: 13
Reply 11, posted (12 years 4 months 2 weeks 3 days 23 hours ago) and read 931 times:
Thanks for the info, but I was wondering is this feature only found on the 744 or is it on all series of the 747?
If it is only on the 744, then what would the difference be from all other series? Does the 744 engines have different characteristics than the 741, 742 and 743 when it comes to reverse thrust?
Here is a picture of a Orient Thai 742 in reverse and the Kruger flaps are still deployed.