It doesn't appear that any Skywest F100 tech crew have responded on this, so , from a charter SLF perspective--things have changed since the introduction of the new system. Inbound to Perth, PM, it was a case of get into the air on scheduled departure time then wait to see how long it would be before the power comes right off. Or how many holding orbits you did inland from Jurien Bay. Watching other flights orbit with you. Now, on the PM flight, departing West Angeles, you will board at sunset, and wait until last light to depart. Announcement about a slot time, get into the air, and then the power comes right back in the cruise. Normal flight time would be 95 minutes, more commonly now is 120 minutes. Can go out to 135 minutes. Slow all the way, but not often having to orbit. Some on here who haven't had to work into the Pilbara may not have noticed that the busiest minesite strips are visual daylight only. So we have to be airborne by last light. Hence you get all these F100's into the air at the same time, and they have to manage it. Less of an issue as the days get longer, probably, delay departure time to lessen time in the air. But I know we've been sitting on the piano keys, midwinter, watching the landing lights grow very bright on the ground ahead. Until the mining companies we work for decide to stagger knock-off times for those coming off-roster , or a third runway is built, it won't change. My money would be on ther third runway option happening first , as easy as the other option sounds.:*

Or something like Rome with 2 holding points each side of the departure runway AA1 and AA2 from memory. 50 seconds between departures for 737 sized aircraft. Granted they seemed to have a dedicated departures runway that doesn't cross the arrival runway. The limiting factor in perth appears to be airspace and separation on the climb though from previous postings here.

CDM
http://http://www.airservicesaustral...fact_sheet.pdf

http://

To hopefully provide a little more info for Nautilus and Transition Layer from an F100 pilots point of view-

We have a very wide speed range in the cruise and can slow down considerably more than the Boeings. We can do anywhere from M0.60 to M0.76 in the cruise so if ATC give us a Julim time the first thing we do is slow down the cruise and leave the descent as profile (normally 0.72/270). Only if at min cruise speed we still cannot meet the Julim time will we then slow the descent profile.
I think Nautilus hit the nail on the head, we loose the time in cruise and you (Transition Layer) are loosing it on descent so we end up with problems!

Ranmar850- Its good to see you have grasp of what is going on with the West Angelas departures, we often think that you guys must think we are just trying to upset you but its far from the case! Often our COBT at West Angelas is after last light and we cannot depart out of there after dark (as you pointed out) so we hold off as long as we can before taking off but as we are early on our COBT we still cop slow downs as soon as we get airborne.

Checkerboard-I can assure they they don't all "get it" :rolleyes:, but there is a generalised, vague understanding that Perth Airport is the problem, and it really is beyond your control. And they all reckon you do a great job into that strip, with all its limitations.
I'm only a PPL (with a lapsed medical :O) but maintain a very strong interest in all things with wings. And you can certainly do some quick turnarounds when your departure from Perth is delayed to the point where you are landing at WA a few minutes before sunset!

One for the Skywest boys and girls flying into West Ang.

http://ranmar.smugmug.com/Motorcycle...les-1-2-XL.jpg

Great pic! :ok:

Checkerboard - thanks for that.
Very nearly learnt that the hard way. Two F100's outbound from PH, same airline, same track, same level, leaving radar, M.07 closing!
I've always thought one thing the F100 is best at is slowing down ;).

Transition Layer - perspective makes all the difference. We would be sitting there cursing the 737 for not slowing down until the last minute. It didn't occur to me that you might be doing a constant IAS. As a radar controller I only tend to think in terms of groundspeed.

It has been suggested that if the fixes were further out it would be less of a problem, because most of the descent would be after the fix, and so therefore everybody would be doing 250kts. The downside would be less time/miles to lose speed to make the fix.

My money would be on the development of matter teleportation before either!

What needs to happen here is talk between ATC and operators. Slow as possible in cruise and high-speed descent is only one way of doing things, IMO not the most efficient, fuel-wise, and it appears not the easiest for ATC. A reasonable-speed cruise and reasonable-speed descent would probably be better.

If ATC tells us officially what annoys them, I'm sure the pilots/operators could adjust their modus operandi to fit in a bit better.

As mentioned, in some types, the descent is where a lot of the time is lost. If there is less descent, less capability to go slow (as well as less time in cruise). We see this on the Julim for 03: the higher crossing altitude leaves us less time to get slow before the FF.

Ironically JULIM for 03 is easier for us because of later descent. If you are still not 5 miles behind at REVOP on 21 its a problem, less so on 03 because you don't need as much descent.

Easiest for us is everybody doing the same, whichever that is. Thats what approach get (in theory) at 40nm, aircraft 2 minutes apart and doing the same speed.

Re talks between ATC and operators, who you get from ATC is the issue. If ASA was an airline, and I was say a 737NG pilot, my immediate superior would not have flown for 15 years, and then it would have been an F100. PH controllers would be A320 pilots, and the FLOW would fly helicopters. The overall manager would have spent the first 18 months of his airline career flying Electra's, and then spent 20+ years in an office.

Hi Bloggs and TL,

Good discussion..quick question. Both 737 I assume, what is a normal descent speed schedule for you guys assuming you have no holding/slow down restrictions and what would be a minimum fuel descent speed schedule at say your average weights arriving to Perth?


Im another F100 driver...I think its quick to assume we should be doing the same thing, but they are different aircraft and they are operated in different ways. It would seem you guys are suffering the consequence of the way we operate the aircraft. I'm happy to help out as much as I can, and having a wider understanding of how things work can't hurt. Bloggs I agree, discussion between operators is good, hence reason for my post!

Nautilus & ATC :ok:

A320 - throw in my three dollars twenty , we tend to drop the descent speed first M.70/220 then go for the reduction in the cruise to fine tune it ... everyone has a way to skin the cat but that's what I have seen the most.

Side thought - weekends we taxi past all the work areas - no one around. Are the penalty rates that high that the boys only work mon-fri ... when all this fuss is happening..... :ugh:

A320: Our company descent profile is cost index cruise in to 280kt. Usually about .78/280.

In order to try to maintain a reasonable profile (not super shallow with ATC steps) I prefer to reduce cruise speed first to a comfortably low speed, then if necessary use that as mach for descent into 280, then start reducing the 280 KIAS. Often you are 10 kt above min clean all the way and still cant make it and thats when a vector helps. Curious though why an orbit (about 2-4 min delay) is rarely available? Is it due to conflicting airways laterally?

ATC has a record of standard speeds for most companies, as yet no requests have been made to vary these 'profile' descent speeds as far as I know (as a pilot pleb). Terminal arrival speeds should be standardised fairly soon though, all going well.

If you need extra mlles, we need to get them done prior to 90nm on the outer sectors (except turbos below F190), partly due workload and partly due congestion. At the sort of levels you are out there, even a four minute orbit is optimistic. The other issue with orbits vs vectors is that we 'lose control' once you start an orbit i.e if you are 1/3 of the way around and we can see you will be late, its too late to fix it, whereas a vector allows more fine tuning. Remember late is much much worse than early.

About 6 minutes is the cutoff for vectoring vs holding. Less than that and you won't be able to get round a pattern, more than that and vectoring takes too much time and attention. There are exceptions obviously. Sometimes if the pattern if full I've vectored for 10+ minute delays well north of REVOP, particularly for non RVSM traffic if we can't get them below F290.

Well, some companies. It also only applies if we haven't given you a delay, which is why this thread has been so enlightening

737-20 ;). Normal .77->295, Min Fuel is Cost Index Zero, .74ish->220.

Bring back the 727 - descent .85/350KIAS to 20nm from touchdown,
or the DC 9 - .82/320KIAS to 15nm from touchdown.
Pilots of the day seemed to like it.

How would the airlines like it if we instructed "cross Julim at XX, descend at 250 knots"? We'd probably have to throw in a few short vectors every now and then, but you'd all be coming in at the same speed without the problem of running parallel tracks and also the issue where number one is descending at 220 and increasing at Julim with number two coming in at 280 and reducing. As Nautilus has advised, a short vector on 125.2 is far easier than trying to tweak times without encroaching Pearce airspace on 133.9.

Bloggs,

Normal descent for us would usually be about .73/280kt.

I tend to reduce the cost index to meet the julim time and if that works I don't worry about changing the descent. However if its a big delay, then we'll start reducing the descent speed. It hasn't occurred to me to try changing the descent speed first...might have to give it a go and see what happens :ok:

73-200?...ah, you must be on the top of Kevin McNamaara's noise complaint hit list? :E

I don't think the issue the speed the F100 flys at, but rather the shorter sectors they fly. It's hard to loose 20 mins on an hour sector, but the F100 is probably the aircraft best to give it a crack.

For me personally, I find it easier and more accurate to cruise at the slower speeds and have the extra power in reserve for increasing to meet the times. There is only so slow you can go (even in the 100 :}) if you've come in fast and need to slow down. And as already mentioned, that is probably the crux of the problem. Too many people skinning the same cat in differant ways.

It was only a matter of time....

Had to get the tissues for that one!

The question is: who is AH? HD? :}