Ask The Pilot

[docjames]

minidoc (4yo) and I waved at you (not knowing it was you at the controls but assuming it was QF94) from South Melbourne as you flew by about 715. Looked awesome with rising sun and clearing sky. It seemed (from the ground) "lower" than usual but may have been an illusion. Great fly-by with great cbd views for the pax.

Is there a range of altitudes at that point? How wide is the "tolerance" for altitude at that point or does it not matter down to a minimum allowable height? (I note your previous comments about high energy and not being too high leaving too much altitude as you close on the airport).

 

[mannej]

minidoc (4yo) and I waved at you (not knowing it was you at the controls but assuming it was QF94) from South Melbourne as you flew by about 715. Looked awesome with rising sun and clearing sky. It seemed (from the ground) "lower" than usual but may have been an illusion. Great fly-by with great cbd views for the pax.

Is there a range of altitudes at that point? How wide is the "tolerance" for altitude at that point or does it not matter down to a minimum allowable height? (I note your previous comments about high energy and not being too high leaving too much altitude as you close on the airport).

Same question has been raised but over the CX cargo flight by a member of a Facebook page.

 

[coriander]

Me too! Likewise stood in the median strip in Beacon Cove unwrapping my paper and emptying out the dog while watching the big bird fly in (jealous as every time I've come home on QF94 we seem to come in from over Eildon and straight into MEL).
Last couple of QF93 outbounds have been to the south but into cloud by the time we're over/near the CBD. No I didn't wave.

 

[clazman]

Does the iPad go into flight mode when on board?

 

[mjt57]

I've found that computer USB ports will charge an iPad slowly while the screen is turned off, even if it's not charging when the screen is on. Of course, I imagine you need the screen on for a fair amount of time.

Totally off topic but my Macbook Air charges my iPad Air as it has USB 3 ports. I believe that they have a higher amp rating than USB2s.

And given that the A380's laptops that they use run Win2k or something like that may give an idea as to their ancientness.

JB, of course, can clarify/correct this.

 

[jb747]

I've found that computer USB ports will charge an iPad slowly while the screen is turned off, even if it's not charging when the screen is on. Of course, I imagine you need the screen on for a fair amount of time.

The laptops are very old devices, in which the wriggly amps are very tired.

For the most part we use the iPads at the start and end of a flight, so on a very long operation like the 94, they might only be running for about 10% of the time. On the monorail, on the other hand, the usage might approach 100%.

 

[mjt57]

On the monorail, on the other hand, the usage might approach 100%.

The monorail?

 

[jb747]

Monorail is SYD-MEL. BNE is a bonus.

 

[jb747]

Does the iPad go into flight mode when on board?

Not quite. We turn off wifi, blu tooth and cellular. That lets the GPS function.

 

[jb747]

minidoc (4yo) and I waved at you (not knowing it was you at the controls but assuming it was QF94) from South Melbourne as you flew by about 715. Looked awesome with rising sun and clearing sky. It seemed (from the ground) "lower" than usual but may have been an illusion. Great fly-by with great cbd views for the pax.

Is there a range of altitudes at that point? How wide is the "tolerance" for altitude at that point or does it not matter down to a minimum allowable height? (I note your previous comments about high energy and not being too high leaving too much altitude as you close on the airport).

The view this morning was quite spectacular, and I wished I'd had the Go Pro. The fog bank ended almost exactly at the MCG. We could see some balloons over Port Melbourne, sitting just above the fog layer...interesting view from there. At the point at which we join finals, we are targeting an energy level equivalent to about 180 knots/3180 feet. The FMC is pretty exact at getting this, and we were right on the profile this morning...so no lower than usual. I'd expect that the 380s on that approach vary by less than 100'.

 

[serfty]

The view this morning was quite spectacular, and I wished I'd had the Go Pro. The fog bank ended almost exactly at the MCG. We could see some balloons over Port Melbourne, sitting just above the fog layer...interesting view from there. ...

I came in from HKG on the 30 this morning - seems about ½ an hour after the 94 but moreso via Heathcote rather then Yarra Glen; landed on 34. Being in an A seat I had a good view of where the fog terminated. Also those balloons were still hanging around. I took a couple of poor smartphone snaps.



Crop and 'blow up' but the lack of definition is apparent:

 

[ChrisGibbs]

JB747 - on the QF127 service from SYD-HKG today I watched "Planes That Changed The World" on the IPAD and they have so far profiled the SR-71, DC-3 and the A380. I was interested in the commentary around the DC-3 where they said this plane was the fore-runner in terms of design (eg. shape of wing) for a number of modern day aircraft. I find it amazing this plane is still flying in commercial service 65+ years after it first went into service. Do you have any perspective on whether some of the modern day aircraft such as the A380 will still be in service in 20-30 years time similar to the life of some of the 747's? I remember as a kid back in the mid 70's at HMAS Albatross taking a look through one of the RAN's DC-3's. During the time in the RAN did you ever get to fly or fly in the DC-3?

 

[747sp]

I noticed the other day that QF 8 diverted to Auckland and thanks to JB’s explanations I now more fully understand why. Thank you. My question is simple, if the captain was having a break at the time the decision to divert was made, does the first officer need to consult with the captain?
Sorry if this has been asked before but also for all the pilots what do you most enjoy about flying?

 

[jb747]

I noticed the other day that QF 8 diverted to Auckland and thanks to JB’s explanations I now more fully understand why. Thank you. My question is simple, if the captain was having a break at the time the decision to divert was made, does the first officer need to consult with the captain?

The decision to divert is made by the Captain. He would have arranged the roster to enable that. If it comes up unexpectedly, he is woken up.

Sorry if this has been asked before but also for all the pilots what do you most enjoy about flying?

There is much that is enjoyable about flying, and it varies at different points in your career. Flying a 380 is more cool than it is fun...fun happens in much smaller aircraft without passengers.

 

[jb747]

JB747 - on the QF127 service from SYD-HKG today I watched "Planes That Changed The World" on the IPAD and they have so far profiled the SR-71, DC-3 and the A380. I was interested in the commentary around the DC-3 where they said this plane was the fore-runner in terms of design (eg. shape of wing) for a number of modern day aircraft. I find it amazing this plane is still flying in commercial service 65+ years after it first went into service. Do you have any perspective on whether some of the modern day aircraft such as the A380 will still be in service in 20-30 years time similar to the life of some of the 747's? I remember as a kid back in the mid 70's at HMAS Albatross taking a look through one of the RAN's DC-3's. During the time in the RAN did you ever get to fly or fly in the DC-3?

I never had anything to do with DC3s...thankfully. I don't think I ever saw the RAN one flying...I think the museum had them in my time, and were working to restore them.

What will become a classic aircraft...who knows really? My beloved A4Gs still live on, flying for Draken International. The oldest is 47...that's not bad. Airliners...the 737 obviously. The 777 perhaps. 767s are a classic machine, but are being sidelined because they aren't cool enough. Nothing Airbus makes will be flying at the age of those A4s....nor will 787s. 380s...much as I like them, are likely to be a short event in the aviation timeline.

 

[wooley]

There is much that is enjoyable about flying, and it varies at different points in your career. Flying a 380 is more cool than it is fun...fun happens in much smaller aircraft without passengers.

Agreed, fun is for small aircraft for sure..

 

[mikenz]

There's increasing media on the potential El Nino. Do the change in direction of trade winds affect flights across the pacific?

 

[jb747]

There's increasing media on the potential El Nino. Do the change in direction of trade winds affect flights across the pacific?

Flights and their routes, are arranged on a day to day basis. Routes often change in flight to accommodate wind updates. I've never heard any association of el Nino and flights from within the industry. But, if you read it in the media it must be true, or not.

 

[smeacs]

Sitting at MEL yesterday my colleague and I were watching a 737 load and were wondering how much the expected weight of the aircraft impacts the fuel carried ? More specifically now that domestic travel has had a shift to more HLO travel and airlines charge for baggage to encourage this has this drastically reduced the fuel needed? Does the weight of luggage remain a consistent assumption or are you presented with a sum weight of all checked baggage?

I guess this became really complex I my head with my simplified model. As more weight (luggage / cargo) needs more lift which needs more fuel which in turn adds weight itself. So what part of this equation is a constant? Or in reality is the fuel calculation weighted more to destination / weather/ diversion requierments?

 

[jb747]

Sitting at MEL yesterday my colleague and I were watching a 737 load and were wondering how much the expected weight of the aircraft impacts the fuel carried ?

A rough rule of thumb (that works for the 767/747/380), is that any additional fuel will be totally burnt in 24 hours. So, stick an extra 1,000 kgs on, and on a 15 hour flight, 625kgs will disappear, just to carry that additional weight.

So, assuming the same rough relationship on a smaller aircraft, on a 90 minute flight, if every passenger carried 2kgs less, and you've got 150 passengers, then potentially you'd save 150*2 kgs * (1.5/24) = 18.75 kgs of fuel. At .7 kgs/litre, that's 26.7 litres. On an individual flight, it's trivia, but on a fleet of aircraft, with reasonable usage, it turns into millions over a year.

More specifically now that domestic travel has had a shift to more HLO travel and airlines charge for baggage to encourage this has this drastically reduced the fuel needed? Does the weight of luggage remain a consistent assumption or are you presented with a sum weight of all checked baggage?

What is HLO travel?

We aren't all that interested in the cargo or luggage weight (they are on the load sheet, but we don't use them for anything). We are given overall figures of weight (the zero fuel weight, fuel order, and take off weight). Load sheets are automated, so we don't need a breakdown of all that is on the aircraft.

I guess this became really complex I my head with my simplified model. As more weight (luggage / cargo) needs more lift which needs more fuel which in turn adds weight itself. So what part of this equation is a constant? Or in reality is the fuel calculation weighted more to destination / weather/ diversion requirements?

It's a combination of everything. The load side of the equation becomes less important on shorter legs. But, you're right that more weight will mean more fuel burnt. Heavier means that you won't be able to climb as soon as planned.

Other things come into play too. On the 94, you are almost always up against the maximum structural weight at take off. So, it doesn't matter what the requirements are at the other end, you can't accommodate them by putting more fuel on. The choices are then between taking load off (and replacing it with fuel), or living with what you have, and planning for a diversion, whilst hoping the weather improves enough to make it unnecessary.