Milan320 From Canada, joined Jan 2005, 872 posts, RR: 11 Posted (9 years 9 months 3 weeks 6 days 3 hours ago) and read 5156 times:
I was wondering if any of you 'bus drivers out there could tell me when managed speed is used (don't know if I got all of ther terminology correct)on the Airbus and when it's not and inputed manually.
Also, what about landings? Is it used often, is it preferable?
Finally one other question, when is the autopilot disengaged for the landing, is it usually after G/S interception or LOC interception (assuming a non-AP landing of course)?
I realize that some of it probably personal preference, but I'm just curious generally when it's done.
RightWayUp From United Kingdom, joined Oct 2001, 86 posts, RR: 0
Reply 1, posted (9 years 9 months 3 weeks 6 days 2 hours ago) and read 5139 times:
Managed speed is normally used, unless there is an ATC speed constraint that is different to FMGC speed. I also use selected speed to speed up if approaching an intermediate level off in the climb to try to keep climb thrust, or to slow down if kept high on descent so as to keep energy in reserve to dive down. Autopilot disengagement is wholly down to company ethos and personal preference. I tend in normal ops to take out the a/p when visual with the runway.
Milan320 From Canada, joined Jan 2005, 872 posts, RR: 11
Reply 2, posted (9 years 9 months 3 weeks 5 days 20 hours ago) and read 5073 times:
Thanks for the reply. It actually occured to me later on today after posting the question when I was playing FS9 when selected speed would be used. Given that FS9 is just that, a sim-game, there is no ATC barking (or if it does, it's never happened to me - rather only a go around request) at you telling you either to slow down or speed up, hence I always keep it in managed speed.
Anyway, thanks again.
Wing From Turkey, joined Oct 2000, 1578 posts, RR: 23
Reply 3, posted (9 years 9 months 3 weeks 5 days 18 hours ago) and read 5058 times:
Its really good to use menaged speed during the approach,ýt will reduce to the next flap speed as you lower the flaps if the menaged speed engaged,but there are some things that you have to be aware of.In busy airports the ATC sometimes ask you to keep 160 kts until the OM to keep the traffic flow,so you have to select the speed 160 until OM,then push for menaged again for the final approach speed.
And especially on A321 at some weights the menaged speed may conflict with the flap limit speed therefore we have to be careful not to exceed the flap limit speed during menaged speed usage.
Also sometimes because of the ATC request or a late descent clearence etc,you may want to descent with higher or slower than FMC calculated speed.There you can "select" a desired speed to fit your needs.
HAL From United States of America, joined Jan 2002, 2585 posts, RR: 52
Reply 4, posted (9 years 9 months 3 weeks 5 days 17 hours ago) and read 5070 times:
I'm based at Las Vegas with America West, and it is busy enough at LAS that I rarely use managed speed until the last couple thousand feet on approach. We almost always get a speed restriction from ATC such as "Maintain 170 knots until 7 DME" or something similiar. I'll get the plane configured comfortably for 170, then at the appropriate point push for managed speed and finish configuring for landing.
On takeoff it starts out in managed, and goes to selected if we need a speed other than what the FMGS is programmed for; for instance if we are vectored off of the departure route and need a quick climb to get over some mountains we'll maintain a lower speed to increase our rate of climb. Or if the plane ahead of us is slow to accelerate we've had ATC tell us to slow down for a while too.
As for the autopilot, it is up to the person flying, and the company policies. Normally it will be clicked off when on final with the runway in sight. However in places like LAS and PHX where we often get 'slam dunk' approaches we'll manually fly it when we can tell that the plane isn't able to do what we want on its own. The airbus is set up so the autopilot normally flys very gently - sometimes ATC instructions require us to be a little more abrupt than that.
One smooth landing is skill. Two in a row is luck. Three in a row and someone is lying.