Qantas PER-LHR and United's LAX-SIN on the 787-9, Technical considerations?
 

Hello everyone,

I was always in a quandary in how do Qantas and United plan on achieving their flight's feasiblility considering that the GC distance on both destinations exceeds 14000kms which is on the knife edge on the 787-9's range. Now, according to Boeing a 787-9 with a 254t MTOW can do 14635kms, but I had a doubt as to whether this includes winds aloft, payload considerations and fuel reserves? Am I missing something on this topic? Is there some way through which both of those flights are technically made feasible for the 787-9 to achieve some extra range or flight time?

Sacrifice payload for fuel and hope the winds are in your favour :p

I think Boeing assumes still air and a full alternate. OTOH, Qantas' planning process does not assume the carriage of alternate fuel while the track winds can often be far more favourable than GC winds. For planning, I think an 85% adverse wind is assumed which means that on 85% of occasions, the actual winds will be less than those assumed in the planning practice.

Does this make sense? It's quite a complex process that's not readily known by most! :ok:

I've heard 4.4 tonnes on arrival, therefore 96.6 tonnes available to burn

4.4T? That's pretty comfortable...in a 737

ROJ.

You are on the money with both comments. I understand QF restrict the A380 take-off weight from DFW so they can get to SYD nonstop. This has the effect of increasing the ground miles per kg of fuel in layman terms. I understand QF accept they will rarely get a MTOW from PER to LHR especially during Winter.

And won't get anywhere near it on a 42 degree day in summer in Perth when LHR is Cat 3B

*lots of close in alt, compared to aus
*early morning arrival (pre 6am) = bugger all traffic
*evening departure = doctor and probably not 42° (although I'd almost bet you could get mtow off per in 42°)

It'll be a pretty light 787 so suspect 4.4 tonne will be 30ish minutes on top of FFR of 30 min and approach and landing.

Still, skinny!

The issue is if they're delayed- say by an hour. That pushes them back into the pack for holding of 20+ minutes as well as on the cusp of 20 hour tour of duty. Suspect lots of stuff happening behind the scene in order to address these sorts of problems.

The question has to be asked, why? Why make flying to LHR such a marginal operation? The vast bulk of the passengers flying on this will be doing 1 stop to London, except PER locals. There is no time saving that I can see, there is no ability to connect to other European destinations 1 stop.

Off the top of my head I can think of at least a dozen ways to get 1 stop to London. It isn't something special. If other operators making their operation as marginal as the 787, it is because they are packing the punters to the rafters, and have the ability to finesse payload vs fuel and have crew duty buffers.

It seems like an incredibly marginal operation to provide an already well serviced route via Asia or the Middle East. There appears to be almost no margin for error, with delay or diversion becoming an operational nightmare. Just about everything has to go right every day, why do it? The real world just doesn't work that way. Competing operators don't have the same self imposed limitations.

Maybe they'll find 230ish pax per day to/from PER- to LHR. Perhaps people will like the stop over in PER instead of Asia if going to/ from LHR.

Many of the comments being made were once made about SYD- LAX as well. Then when MEL- LAX kicked off there were similar points made.

I hope they make a go of it. Perhaps we'll find within a couple of years that PER- direct to a bunch of places in Europe will become the preferred model for people travelling.

Last time I was in Perth on the B787-9 we couldn't get out of there at MTOW on runway 21 with nil wind and 34 degrees. The B787-9 doesn't perform all that well when the temp starts getting past 30.

Why do it?

PR simple. The biggest, the best, the longest, the fastest.... QF are trying to compete in the game of perception.

It is not about sense or operational certainty.

Thanks for the informed comment :)
Typical boeing dog eh

Although that does actually surprise me; are there different engine ratings available?

I look at it in the same way I experienced on the west coast US to Oz non stops in the early days. Some times you made it, and on occasions a stop in Nadi to top up. Prefer direct to where I'm going if available. Full marks to QF if it works.

It'll make it fine way more often than not. Qf are well skilled in the balancing act ex DFW in that regard.
Whether 60 (?) J class can be filled daily and a sardine can are appealing is more my concern

I also can not see the advantage for anyone, except Q, in this operation.
Sydney - LHR with a half way stop seems more appealing to me, if in cattle class, than 4 hours to PER then a loooooong flight to London.
One point to consider, is that this proposal was used by Q as a very long lever to get international operations running out of "their" terminal.
Thin end of the wedge ?????

Will the new 777 be able to go PER LHR direct? Maybe they test the waters and then get an aircraft capable of doing the flight more consistently in the future.

The 200LR can do it today without breaking a sweat, the question is could you make money? and of course QF don't have any of those airframes.

they dont make the 777-200 anymore do they?

I don't think any -200LR have been delivered recently but I don't see why they couldn't be built if someone wanted.

The -200 length fuselage is still manufactured for the freighter, and the rest of the -200LR is more or less the same as the -300ER

Of course it will work fine most days, QF would be insane to think about it at all if that wasnt the case. The problem is two fold
1) Any problem gets highlighted by media-worlds longest flight nearly runs out of fuel etc
2) The destination is LHR where on tiny hiccup can ruin a lot of folks day and a tiny hiccup at the end of 20 hour trip is more of a problem than if the flight started in Berlin or even JFK . LHR imposes its own brand of delays quite often and QF dont have much a a presence in Europe if they are going to divert .

In answer to your original question about technical considerations to help them make the distance;

We are told that Qantas are going to great lengths to look at every item installed on the aircraft to see where they can save weight. Removing unnecessary galley fittings, light weight trolleys, this week they were even talking-up new light weight cutlery and crockery.

Qantas are also in the final stages of work on a completely new flight planning program. They had a university robotics team write the code to optimise the chosen flight path. It's supposed to analyse thousands of different route, level and speed combinations to find the most efficient route. It is far more advanced than the current system in use.

And then there is the fuel policy, ie. not carrying fuel for an alternate. (That's a well worn debate that I don't intend to revisit).

All these measures, and I'm sure many more, will help to make incremental increases to the range achieved by the 787-9.

Just for clarification. It's not the worlds longest flight. Doha-Auckland has that title.

I don't get this "thin" bit comment/s

Flight planning is not a guess it is a formula and that formula has built in factors for regulatory requirements.


At the end of the calculation "x" fuel is required or the flight can not happen - X is not a thin number, it is the number that should have you at your intended destination with required reserves.


Should a variable be greater than expected during the flight in the flight plan, then the options considered in the flight planning may need to be used such (as a divert for fuel). That does not make it "thin" it is in the plan not to run out of fuel.

I expect that a divert for fuel would make the profit margin thin, but that is not one of the factors in the flight planning formula.


* It could draw a few punters from the East Coast that have family in Perth but don't want all their holiday there but want to also head to Europe.

If u need to manage payload to get to destination its thin

Are they standard narrow 787 seats on the Q 78's? I would not fly economy class in a 787 for that long.

So if I configure a 787 to a single class - First Class only, the flight will no longer be considered thin?

How is that not managing payload?

Just like singairs SIN-JFK

I gather the SIN JFK route and the Singapore A340-500 fleet was heavily subsidised by Airbus. How many A340-500's did Singapore have?

Capt Fathom

SQ had 5 x A340-500 a/c. 9V-SGD is now operating with the Las Vegas Sands Group. Airbus are stuck with the other 4 a/c which are parked at Lourdes. SQ also operated a short sector SIN-JKT daily with the A340-500 for crew proficiency purposes. Airbus has dropped a bundle of $$$ with the A340-500. There are some new a/c available from Airbus that have never had an owner. E.g Built in 2008 with just 47 flight hours and a small number of cycles.

Qantas have been pushing the envelop with long range flying that's payload limited for decades. I think you may find that they pioneered it and even showed PanAm how it was done between LAX and Sydney. You can be sure that they know what they are doing! :ok:

Actually, you're both a little bit wrong. If you're referring to the original Boeing justification for the 787 - 'long, thin routes'. As it's turned out, you're not far off.

The "thin" is meant to denote a route that couldn't support capacity (777, 380 etc). But the route did require range. A 767 size aircraft that could go anywhere. Think medium sized city. Remember United's first planned route ? IAH - AKL.

It's turned into something entirely different. But that was the original 'thin'.

"You can be sure that they know what they are doing" . Can I hold you to that Ken?

Now that actually sounds correct "the number of expected pax are a bit thin to support an aircraft of type X.

:ok:
Boeing philosophy - point to point - 787
Airbus - hub to hub - A380

...and point to point A350.

Of course there's differnt ways to view things, but for aircraft x (789 in this case), two side by side routes - the one they manage the payload is the thin one as the yields must be higher to offset reduced headcount and higher fuel costs.
Either way we wait with bated breath

And hub to hub - 777X

---which hasn't been invented yet.