I don't know about that...if my performance was suspect I'd be ducking down one of the numerous valleys north of 35 so as to avoid the obstacle rather than sit there and hit it! :ok:

Network have failed their CASA RPT audits TWICE! The guys at Fort Fumble have given them one more chance before they won't allow any more attempts.

Didn't see that in the staff newsletter did ya! :E

Fuel-Off :ok:

BPA, just checked CAO 20.7 and above 22.7t you must calculate for IMC; no relief for VMC on-the-day:

Might be part of the reason MD bailed to VARA

Bloggs,

Visual DEPS are also issued out of TL.

In the four types of HC jets I've operated out of CBR never had a problem using 35 in summer and operating DCT to BN, CG and AD.

What was the reason they failed the application (Twice)? I thought WW is heading up the application process and he was previously the regulatory affairs manager.

MD was pushed aside from his chief pilot role and bailing out to VARA was a good way out (of Qantas) for him.

That may also be so. But you can't just say "oh it's visual, let's use the VMC only RTOW". Performance-wise, the type of ATC departure is irrelevant.

Hence this thread! :) If you can get to BN off 35, you'll certainly be able to get to CG or AD...

CBR gradients
 

Ahh, Bloggs,

Leave you alone for a few years and you forget everything... := :uhoh: :oh: please throw the shovel out of the hole!

josephfeatherweight,

Yes, the OEI SDP gradient off 35 is around 3.2% - Type A is considered, along with other data, and there are procedural fudge factors for tree growth, survey errors, etc. That gradient is what underpins the RTOW calculations. :ok:

How's it Hanging,

Careful of the great myth that the gradient off 17 is so much lower than 35 - it is only 0.2% less, depending on how you plan to get out of the Tuggeranong Valley - and the tailwind may certainly erode that slight advantage when considering achievable OEI gradients... :eek:

BPA,

I never had a problem either. In a couple of memorable cases, that was only because nothing failed and so otherwise erroneous planning was never put to the test.

Did you mean that you flew four types of high capacity jets that had no performance restrictions below MTOW up to 42.2 deg off 35? :ooh: :ooh: :ooh:

If so, I would appreciate you identifying the types and the departure path so that I can improve my knowledge of OEI performance of jet aircraft in Australia. Please?

And generally,

The aeroplane doesn't know if it is in VMC or in IMC. It can't climb any better just because you can see what is coming. Try a quick right turn off 35 OEI and see just how high Majura Range really is - particularly after discovering what a turn does to your climb!!! :ugh: :ugh: :ugh:

Stay Alive,

Which piece of legislation allows them to refuse an application?

Qlink Cobham 717s payload limited
 

Why is it such a big surprise there are performance limitations out of CB. So 3.2% is the net gradient used for the CDP meaning you need 4.0% to get off 35 OEI. Given that's a fair bit more than the 2.4% min I'm surprised any jet can get off at mtow. From memory the jet I fly drops about 40t off mtow at about 25deg.

Must be an airbus Joker............:O:O:O:O

I don't think the surprise is that the jet is performance limited, Joker. As you say, most jets are limited at or approaching their MTOW.

The surprise(or lack thereof) comes from the fact that QF management oversaw the acquisition of another jet that is not entirely suited to the task employed.

If they haven't considered a 30+ degree day with 5kts tail and OEI, then they have not done their job properly and should be held accountable.

stretching it a bit
 

OneDotLow,


What I gathered from the thread was some obvious trolling and some vaguely serious discussions about route planning options. I'm not quite sure what propelled you into:

Wasn't the discussion about deciding when and for how long you pay for the higher thrust rating?

I would have thought that being able to dial up the thrust (15 minutes on the tools and 45 minutes on the paperwork) on a pay-as-you-go arrangement is eminently flexible, both operationally and financially. :ok: :ok:

But is it really that simple and cheap an exercise?

Yes it is. The rest of the fleet has an upgrade approaching summer and a downgrade approaching winter, every year.

Cheap? Maybe not, but it depends on the value you put on being able to fill seats.

simple and cheap?
 

OneDotLow,


Looks like I'm slightly late to the game, but that's the price of being old and easily distracted...


Anyway, my reading of the tealeaves presented here is that it is all relative to your decision metrics:


- The simple things are increasing the thrust rating and writing the cheques to pay for it for as long as you do it.


- I gather that the cost for the increased thrust is particularly expensive.


- I surmise that having the flexibility to do a daily/weekly/monthly/seasonal change is particularly cheap compared to funding a permanently higher thrust rating


- making the decision is simple if you are happy with your decision metrics


- life rarely permits simple decision metrics when the cost of an error is high.


I have to admit that route planning and yield are most definitely not my bag, but my experience operating to and from Canberra suggests to me that it would be a very difficult market in which to closely modulate capacity (a consequence of performance) given the distortions due to Parliamentary sittings, the dominance of government-related travel vis a vis tourism and private travel and the effect of seasonal weather. :E

Qlink Cobham 717s payload limited
 

I see the problem as having 40 min traffic holding at BN. This means you need to take around 3.5 hrs of fuel for a 1.5 hr trip if there is a tempo on. That's never going to be efficient.

This whole discussion misses one important question. The flying was transferred from a 737 to a 717 due to cost savings. Is the updated thrust required to do the job properly part of the new cost and how much cheaper is it really?
Who de- ices it in winter and who pays for it? Like everything in Qantas the true costs are a blurred paradigm of smoke and mirrors. We shut down the APU on turnaround to save fuel but the 717 doesn't cause Qantas picks up the tab. Why aren't Qlink pilots flying the 717 instead of Cobham. Surely it would be cheaper and offer career progression. Or here is something novel. Why can't some pilots from mainline fly the thing for free! Yep they're getting paid to do bugger all at the moment. Bucket loads of F/O's with 10,000 jet hours wanting a left seat. Go figure!

You assume it is about cost. It is about fulfilling the QF master plan, of breaking up mainline and replacing it with subcontractors.

Unfortunately at the rate they are going they could end up sinking the whole thing. Whether that is part of the plan or not is yet to be seen.

Been away from CBR for a couple of years but on those hot Canberra days we often had weight problems on the 734's on the CBR BNE route and also from memory on ADL

Troo, if you wanted the discussion to focus on the industrial aspect, why did you start the wind up by taking a crack at the performance of the 717?

I am curious, who you are directing all this spleen at? I hope it is not the Cobham crews them selves, it would be a shame to perpetuate the whole "divide and conquer" strategy you claim the 717 is a part of, by making it a Cobham v's qlink/mainline thing. May I suggest you write a strongly worded letter to AJ stating you disapproval instead?

And here was I thinking the flying was transferred because aged 734s were retired and replaced with 738s, which in turn are to be used on better yielding routes more suited to the 738's capabilities. This left a hole. What to service the routes covered by the retiring 734s in the face of Virgin's Jungle Jet expansion?

Fleet utilisation numbers...
 

A friend was recently bemoaning the current 737 fleet utilisation numbers: twenty years ago the fleet average was around 10 hours/day...and a lease cost around $323,000/month for a -400

Today our resident math genius has driiven the daily use down to circa 6 hours while paying slightly more per diem for a lease.

The idea that 738 hulls are being freed up for more profitable routes is true in theory, but does not appear to have a basis in fact.

As an aside, it does cost QF a lot less for an overnight crewed by cabin crew on 33K/year (717, as revealed by one of their crew): 1/3 the mainliine cost approximately.

Can someone here reveal what meal payments the 717 "enjoy"?

Capt Claret,

Are you suggesting there is some intelligence at Q to use appropriate planes on better yielding routes more suited to their capability? Surely you jest.

Quite a lot, considering it drinks around 2t per hour. With AVTUR at record prices, I'd reckon about $8000 a day! :eek:

curious
 

Hey Clarrie,


Just curious, did you have an answer to the question about the critical temp for each engine that reduces the RTOW below MTOW for 35 at Canberra? :confused:

Australopithecus
At 6 hrs per day, plus say 2hrs turnaround time,

Where exactly are the 737s sitting outside of 9-5.

moa999, I disagree with 6 hours for the 737, it is somewhere between 7:00 & 7:30 hours per day on the numbers I have seen. And still there looks like being a net increase of 7x 737 aircraft this year. Retirements of the 767 need to be considered, how this affects the average remains to be seen.
You have made an assumption that they are doing straight (0:35) turnarounds - that isn't the case, except in limited space apron / high frequency outports (KTA,PHE,BRM etc). They tend to do longer turns, particularly during the middle of the day. The net result is two departure peaks, early morning and late afternoon / early evening.

Net increase of 7?
They are retiring 3x -400's, so you are saying they are getting 10 new -800's?
I haven't seen that anywhere.

My understanding is that a new -800's keeps coming every month until end of ~Q3 14 (a little vague on exact number & timing), while the -400's will be gone by the end of Feb. (Basically a 1:1 exchange until now). Net 7 new -800 airframes, but am willing to be corrected.

Only 5 more B737-800s coming - delivered monthly from July to November 2014. I don't think that you can consider them as additional airframes as they are effectively replacing 255 seat B767's (there are not enough A332's being returned from JQ to replace the entire B767 fleet).

Sorry, slightly off topic but to address fuel offs "concerns", Network RPT route proving flight booked for mid Feb, my mail is they failed nothing but as per usual CASA have asked for quite a lot of re writes and amendments etc. I think going from GA with jets to RPT was a little more involved than they thought.
But 20 red tail A320s? Highly unlikely. A few green tail 320s not out of the question tho, and who knows, with Jetstar Hong Kongs continued great performance there could be a few spare in the group shortly

Capt Claret,

Are the RWY35 figures from the full length (only used if operationally required) or from intersection 'N', which is used 99% of the time?

The best I can do is give a comparison at ASP, 100' elevation less than CBR.

Bleeds off, nil wind, standard pressure.

RWY 12 A engines MTOW to ~ 29C, C Engines ~ 44C (A eng ~ 6 tonne less @ 44C)
RWY 30 A engines MTOW to ~ 27C, C engines ~ 43C

more grunt
 

The 21k gives an extra 5T, I assure you!

advantage of higher thrust
 

Clarrie,

Thanks for that. Although the departure gradients are substantially different, the figure do illustrate very nicely the advantage of the 21K engines over the 18.5K engines at ASP. :ok: :ok: :ok:

Andyn,

Welcome... :) ;)

Unfortunately for those folk who are not as familiar with the 717 performance, just promising an extra 5 tonnes doesn't mean a lot. Given that the uncontrolled variable is the OAT, the increase in critical temperature for MTOW tells most of us quite a lot about the advantages of dialling up increased thrust. :cool:

BPA,

You are quite right to highlight the typical N departure, but I think for this context the full length is relevant since that is your last option before restricting the load. :cool:

Stay Alive,

Quote: The best I can do is give a comparison at ASP, 100' elevation less than CBR.

Remember that one of the most (if not the most) limiting factor when determining RTOW is the obstruction weight limit which is a function of obstruction height and distance, temperature, airport elevation and wind, etc.
The obstruction height and distance from CB make it more weight limited than the Alice.

Obstacle not obstruction.

An obstruction prevents passage. An obstacle can be avoided.

So is CASA an obstruction to aviation, or an obstacle to it?

definitely the latter, very nearly the former

give it time