Shamrock1Heavy From Ireland, joined Nov 2002, 250 posts, RR: 0 Posted (12 years 4 weeks 5 hours ago) and read 1670 times:
Hi - My instructor was only limited to knowlage of small twin engine prop gears....so here it goes
On a large transport jet (i.e - 747, 777, A330,A340 etc..) When is the gear extended? When the hit that V speed (is it Vle?) ? On final? or trying to bleed speed off trying to slow down before landing? I am talking like genrally, Like a normal flight, at a large airport...
AAR90 From United States of America, joined Jan 2000, 3516 posts, RR: 45
Reply 1, posted (12 years 4 weeks 4 hours ago) and read 1641 times:
Whenever I need it.
Seriously, I try to hold lowering the gear as long as possible --saves fuel-- but have found the 738 needs the gear's drag a lot more often than I'd like. If possible, my goal is to lower the gear such that the landing checklist is completed exactly as we pass 1000' AGL (a checklist required callout of "checklist complete"). Anything earlier than that costs fuel ($$$).
*NO CARRIER* -- A Naval Aviator's worst nightmare!
Cx flyboy From Hong Kong, joined Dec 1999, 6667 posts, RR: 55
Reply 2, posted (12 years 4 weeks 4 hours ago) and read 1645 times:
The landing gear can be useful in helping to slow down when you don't want to use the spoilers. However, usually I lower the gear in the 777 at around 2300ft AGL on finals. We cannot lower flap 30 until the gear is down otherwise we get a warning. In order to have Flaps 30 and landing checkilst complete at around 1500 (1000 latest) I lower the gear at around 2300. On some days however, in a heavy -300, without the gear the speed increases as we go down the glideslope, even with thrust at nearly idle. Putting Flaps 20 out early may not be enough to slow the speed so the gear goes out earlier than I would normally do it.
In some places like Tokyo Narita's Runway 34 approach, you are required to put the gear out very early (Over the sea), to prevent blocks of ice from falling down on houses. Not sure how much of a problem this really is, but the approach plate says to do it, so we do.
Scootertrash From United States of America, joined Aug 2001, 569 posts, RR: 9
Reply 3, posted (12 years 3 weeks 5 days 3 hours ago) and read 1435 times:
In my lowly Dash 8, the gear is a major slow down tool, since Vlo is higher than Vfe at any flap setting. With that said, I try to hold the gear up until 1500' AGL on a instrument approach and 1000' on a visual, just to keep things smooth and quiet for the folks.