Ask The Pilot

[straitman]

Could be anyone flying as what's known as an 'Approved Technical Observer'

For instance, us pesky air traffic controllers do such jump seat flights every now and then to give us an insight to things from a pilots perspective.

.... or a CASA FOI .

 

[jb747]

Maybe I haven't woken up, but it seems at 30 miles I should be at 96,000 feet?

Interesting 91,000 foot descent over 10 miles to reach to 5,000 feet at 20 miles ;-)

Well, it's 3.2 times something....

30,000'.... 30*3.2....96 miles

or

50 miles....50*3.2.... 16,000'

Hard to do after a couple of glasses of red though...

 

[jb747]

jb, going back to the QF 30 incident, in the ATSB report it says: "After clearing the baggage and cargo from the forward aircraft hold, it was evident that one passenger oxygen cylinder (number-4 from a bank of seven cylinders along the right side of the cargo hold) had sustained a sudden failure and forceful discharge of its pressurised contents into the aircraft hold." But from what I understand from this: "While it was hypothesised that the cylinder may have contained a defect or flaw, or been damaged in a way that promoted failure, there was no evidence found to support such a finding. Nor was there any evidence found to suggest the cylinders from the subject production batch, or the type in general, were in any way predisposed to premature failure." There has never been a clear picture as to what made this particular cylinder fail, has there? Are these cylinders in an area of the aircraft that is accessed by ground staff or only by mainteinance staff? Thanks for this amazing thread.

No, there was never a definitive answer. The failure mode fitted best with an inclusion in the metal, but that was unprovable, as they had no part of the bottle itself.

The bottles concerned are on the side of the cargo hold. Out of the way, but not hidden. There are other placements as well.

 

[jb747]

JB, as your work involves only long haul flights, what is the attraction of that over say, domestic ops, other than the money (flying A380s)?

Do domestic pilots get to sleep in their own beds on a more regular basis?

And I can only imagine how complex the scheduling for pilots is to manage it all.

I've always seen domestic as being like having a real job...you have to go to work on most days. More drives through the traffic. International is more like a fly in fly out mining job. Go to work for a week at a time, then go home.

 

[jb747]

After I posted this in another thread, mannej kindly suggested that I ask it here.

While obviously not identical from year to year, with what rough frequency do go arounds (missed approaches) occur at each major Australian airport - are we talking 10 a month if that when the weather is good and stable, but many more when it isn't?

Of BNE, SYD, MEL and PER, what would be the ranking for the number of these incidents? There appeared to be one this morning at MEL involving CA177 ex PVG.

I have no idea how common they are overall. More an ATC question. I haven't done one for about 6-7 years, though when I flew the 767, and did a lot more domestic Australian sectors, I guess I averaged about one per year. The frequency will vary dramatically with the weather. I've seen days on which most aircraft are going around, with very few managing to land.

The public and media have the entire concept of go arounds reversed from their reality. As a part of aviation, they are a non event. Push the power up, and you've simply converted the approach into that bit of flight that happens just after take off. They are not dangerous, nor are they in any way reportable.

But, you have to remember just why a go around is being done...they always happen because the option to continue has expired. They are always the safest choice.

 

[Skyhigh777]

Is the decision to go around more of a gut feeling on the captain's part that something is wrong, or is it more of a technical decision?

Thanks

 

[Mattg]

I noticed that last night QF82 and BA15 took considerably different routings despite both being SIN-SYD flights and both leaving within an hour of each hour. BA15 crossed the West Australian coast north of Derby, while QF82 crossed close to Port Hedland. (For the record, QF6 from SIN to SYD a couple of hours later flew an almost identical route to QF82).

Here is a link to the flight paths:
QF82: Qantas (QF) #82
BA15: British Airways (BA) #15

Do you have any idea why there would be such a difference? I had assumed the routings would be more or less identical in these sort of cases.

 

[jb747]

Is the decision to go around more of a gut feeling on the captain's part that something is wrong, or is it more of a technical decision?

It can be either. There are laid down limits that affect instrument approaches, as well as required 'stability' (i.e. speed, configuration, etc). Sometimes though, it just doesn't look right. It's always much easier to explain a go around that wasn't necessary, than to sort out the mess that can result from a landing that should not have happened.

 

[jb747]

I noticed that last night QF82 and BA15 took considerably different routings despite both being SIN-SYD flights and both leaving within an hour of each hour. BA15 crossed the West Australian coast north of Derby, while QF82 crossed close to Port Hedland. (For the record, QF6 from SIN to SYD a couple of hours later flew an almost identical route to QF82).

Here is a link to the flight paths:
QF82: Qantas (QF) #82
BA15: British Airways (BA) #15

Do you have any idea why there would be such a difference? I had assumed the routings would be more or less identical in these sort of cases.

Not everyone can fly the same route and expect to get the desired levels. Sometimes it's worth taking an alternate if it won't be used by many others. The flight planning programs look for the minimum cost route. It's possible that that might be slightly longer, but it might give better winds, or lower overflight costs. BA and QF would have different costs for many of the items on that particular route, especially as they're not the same aircraft type. The upshot is they aren't easily compared.

 

[legroom]

Hi JB,

At the time of my recent QF2 pushback, the captain advised there would be turbulence ahead over ... some part of Australia which I now forgot and it turned out to be correct.

That lasted a good 5-10 min with the captain on the PA advising pax / crew to put their seat belts on.

How could you know so far in advance there would be air turbulence - as distinct from storm, snow etc.... ?

Included in the long range forecast ?

From previous flights on same route ?

Thanks

 

[Mattg]

Not everyone can fly the same route and expect to get the desired levels. Sometimes it's worth taking an alternate if it won't be used by many others. The flight planning programs look for the minimum cost route. It's possible that that might be slightly longer, but it might give better winds, or lower overflight costs. BA and QF would have different costs for many of the items on that particular route, especially as they're not the same aircraft type. The upshot is they aren't easily compared.

Thanks for the answer JB. May I ask what you mean by "overflight costs"?

 

[jb747]

Hi JB,

At the time of my recent QF2 pushback, the captain advised there would be turbulence ahead over ... some part of Australia which I now forgot and it turned out to be correct.

That lasted a good 5-10 min with the captain on the PA advising pax / crew to put their seat belts on.

How could you know so far in advance there would be air turbulence - as distinct from storm, snow etc.... ?

Included in the long range forecast ?

From previous flights on same route ?

Sometimes there are quite specific reports from other aircraft, but on every flight we have prediction as part of the flight plan. On a scale of 0 to 9, if it mentions 8 or 9 then it will be bumpy.

 

[Himeno]

Thanks for the answer JB. May I ask what you mean by "overflight costs"?

The nation which owns the airspace being flown through charges the airline for use of that airspace.

 

[Mattg]

The nation which owns the airspace being flown through charges the airline for use of that airspace.

I never knew that! So do airlines often plan routes so as to flew through as few countries' airspace as possible?
How is it charged? E.g. a one-off fee or by the hour?

 

[jb747]

I never knew that! So do airlines often plan routes so as to flew through as few countries' airspace as possible?
How is it charged? E.g. a one-off fee or by the hour?

The exact mechanism of the charges is probably commercial sensitive. Not a small amount in any event.....

 

[petercr]

JB, I know you've mentioned that there are many (20?) fuel pumps on an A380 but I would have thought that in the case of QF94 in the last 24hrs that it would have been more prudent to land in Hawaii rather than turn around and fly another 4.5hrs back to LAX (where I believe it had left approx. 2hrs late anyway). Can you elaborate?

 

[jb747]

JB, I know you've mentioned that there are many (20?) fuel pumps on an A380 but I would have thought that in the case of QF94 in the last 24hrs that it would have been more prudent to land in Hawaii rather than turn around and fly another 4.5hrs back to LAX (where I believe it had left approx. 2hrs late anyway). Can you elaborate?

Off the top of my head, there are 28 pumps. And all of the tanks, with two exceptions, will gravity feed as well.

Prudence only comes into the equation if there is risk. In this instance, it would seem that the only consequence is the loss of the fuel from the affected tank....everything else would be available. So, basically the aircraft has lost access to about 10% of the fuel load. You cannot reach destination. You are choosing the best airport to fly to, and then be unserviceable at. Go to HNL, and you will almost certainly have to wait a couple of days before you get the engineers, and parts, to go on your way again. Back to LA, and the expertise is there...

Inconvenient and annoying, but the best way to handle it.

 

[Quickstatus]

Hi JB,

does QF7/8 have a non fuel payload handicap to enable consistent on time arrival?

would the A380 have to take a payload handicap as well if it were to do the same journey?

 

[Moody]

On the turbulence theme - I was recently on an A380 out of LAX and was upstairs at the back. We encountered turbulence shortly after reaching the initial cruise altitude, and whilst it was never bad enough for the seatbelt sign to come on it certainly made the dinner service entertaining. This was mainly because the cabin was making a wagging motion. This meant that wine had to be held in one hand if you wanted to drink it rather than wear it.

Perhaps it is because I am normally seated over the wings that I have never experienced this phenomena, but does the sheer size of the A380 make the fuselage flex more obvious? Or is side-to-side turbulence less common than the vertical bumps I am used to?

 

[markis10]

The exact mechanism of the charges is probably commercial sensitive. Not a small amount in any event.....

For Australia they are available online
Charges and costing | Airservices

Terminal Nav	Rescue & Fire	En-route	Met Service	Total
Charges incl. GST	$2,229.70	$1,329.85	$2,837.61	$196.24	$6,593.40
GST	$202.70	$120.90	$257.96	$17.84	$599.40
Rates	$5.60	$3.34	$4.04	$0.254

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[h=3]Flight details:[/h]

Aircraft Details
ICAO type code	Chargeable Weight	Assessed Noise Level	Charge type
B744	398,160 kg	299.4	Jet
Dates and Times
UTC date	UTC Time	Local Date	Local Time
Monday, 27 Jan 2014	1925	Tuesday, 28 Jan 2014	0625
Airport Details
	Departure	Arrival
Name	HONG KONG	SYDNEY
Code	VHHH	YSSY
Location	Foreign	335646S 1511038E
Chargeable Distance	3,520 km (approximately 1,899 naut. miles)

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