TN486 From Australia, joined Jul 2008, 816 posts, RR: 2 Posted (4 years 9 months 3 weeks 1 day 8 hours ago) and read 3180 times:
I am strictly an amateur guys so please all you techies dont give me stick, I just wish to learn!!
I live immediately below a S-SW approach to MEL, this approach is normally flown by all ac incoming from TASMANIA, for arrival runway 27. The point they fly over my home is normally 17-18 minutes to touch down. At this point JQ A320's sound as if the engine/engines are "winding down" momentarily then almost immediately they are "winding up" again. In some cases it happens a second time, then everything then goes back to normal. Any thoughts please.
remember the t shirt "I own an airline"on the front - "qantas" on the back
AAH732UAL From , joined Dec 1969, posts, RR: Reply 2, posted (4 years 9 months 3 weeks 1 day 1 hour ago) and read 3133 times:
Quoting TN486 (Thread starter): The point they fly over my home is normally 17-18 minutes to touch down. At this point JQ A320's sound as if the engine/engines are "winding down" momentarily then almost immediately they are "winding up" again. In some cases it happens a second time, then everything then goes back to normal. Any thoughts please.
Probably leveling off. If you say they are that far out from the airport, they are probably just finishing up their crossing restriction and are leveling out for further descent.
Quoting Ceph (Reply 1): Jet engined planes need to cross the threshold at a certain percentage N1
Not really, just at or above Vref and at or around the TCH(Threshold Crossing Height) for the type of approach.
Airbuster From Netherlands, joined Mar 2007, 385 posts, RR: 1 Reply 5, posted (4 years 9 months 3 weeks 11 hours ago) and read 3055 times:
Maybe there is a level restriction right above your place, that would mean they have to try and make it, say for example they all have to be at or below FL150. If they are getting on the high side, they may spool down to have a greater descent rate, and once made the restriction spool up again for a slower descent.....
but hey, i'm sitting at the other side of the world so don't know the procedures.....just my thoughts.