Ask The Pilot

[WheelieBagWanderer]

Hello JB,

A few quick questions if I may.

1. I was listening into the ATC app the other day, and I noticed after take-off that aircraft were told to "contact Director on.... "
Who is "the director?" Why wouldn't you contact "Departures?"

2. On a flight, say, from SYD-BKK.... What air traffic control centres would you talk/report to on the way there?
Obviously SYD at the start, BKK at the end, but how about over Central Australia, Indonesia, Borneo, Vietnam, Cambodia (assuming that was the flight path, which it often is).
Do you need to talk to each country's ATC as you fly over, or is there a centralised-"SE ASIA ATC" for cruising aircraft?

3. The last question refers to top of decent. Obviously you have this in your flight plan from the start and it's entered into the FMS. How is this particular point on the map calculated? Do you have to confirm this TD point with the arriving airport's ATC before you actually start your decent? Also, if it is a busy period and they ask you to change your TD point, or alter it in some way, such as enter a holding pattern, do you then have to reprogram the FMS? If you're not sure what they're going to ask you to do after holding or what level they're going to instruct you to fly to, or what waypoint they'll send you off to next what do you enter in the FMS? Hope this makes sense.

Many thanks as usual.

 

[Robbi]

Hi JB

Here is something silly for you to ponder (and hopefully as distraction from all this QF32 business).

I have a silly question that has been in the back of mind ever since I saw something on Mythbusters.

If a jet such as an A380 or B747 was placed on a huge treadmill such that it always remained stationary as far as forward motion was concerned; could the engines move enough air over the wings or provide enough thrust such that the aircraft could become airborne?

I have always have had thoughts for both yes and no but really I'm just guessing. So I thought that a pilot is probably the best person that I know to answer something as silly as this.

Many thanks

Don't forget the aircraft moves by applying thrust against the air not the ground.

 

[petercr]

Don't forget the aircraft moves by applying thrust against the air not the ground.

Unless it's a Harrier (or a YAK-141 or an F35B)

 

[straitman]

Unless it's a Harrier (or a YAK-141 or an F35B)

The same as a helicopter if they are out of ground effect then they still apply thrust against the air.

 

[Flying Fox]

No. A wing works because of forward motion.

As jb747 noted, by specifying that the aircraft "always remain stationary" you've nixed your thought experiment before it has begun. However, holding the usual assumption for this problem of non-slip tyres and frictionless axles, your treadmill is theoretically impossible to create - even at idle thrust, on a treadmill belt moving at infinitely high speed, the aircraft would still be able to move forward relative to the ground and, more importantly, the surrounding air mass.

So the reason it won't fly is not because it's on the treadmill, but because you've specified that it's stationary.

Don't forget the aircraft moves by applying thrust against the air not the ground.

Thanks all for your answers. Now I feel a little silly debating all this in my head for so long; the answer seems very clear now!

 

[mjt57]

JB,

what are your thoughts on this news article?

No Cookies | Herald Sun

Late last year one of these buildings was rejected due to the flight path restrictions. One of your colleagues, might've been Capt. Jackson, not sure, was spoken to on the radio. And gave a good explanation as to why the restrictions are in place.

I got the impression that it affected flight paths into MEL as well as Essendon. But in this article the fellow is refering only to Essendon.

 

[petercr]

Similar has been in play with BNE as well especially with the new runway now starting to take shape. AFAIK, the two latest Meriton constructions are about it height-wise

 

[markis10]

Similar has been in play with BNE as well especially with the new runway now starting to take shape. AFAIK, the two latest Meriton constructions are about it height-wise

Brisbanes restrictions are not flight path related, more so radar issues, the limitation on 111+222 to 274m was as a result of CASAs objection on that basis. The CBD is nestled in a pocket that does not cross any runways extended centrelines, landing to the north the aircraft track downwind over the Gap if they don't do a breakfast creek approach, taking off to the south they set course over Morningside.

 

[iRobbo]

Brisbanes restrictions are not flight path related, more so radar issues, the limitation on 111+222 to 274m was as a result of CASAs objection on that basis. The CBD is nestled in a pocket that does not cross any runways extended centrelines, landing to the north the aircraft track downwind over the Gap if they don't do a breakfast creek approach, taking off to the south they set course over Morningside.

The buildings affect the radar lowest safe altitude. When that building was under construction it affected the climb gradient of the Runway 19 SID that went straight ahead. It also increased the radar lowest safe altitude in the sector that affects left base or straight in approach for Runway 01 from 1900' to 2100' (that was daylight hours only). The CBD will affect the approach path of the new runway

 

[jb747]

what are your thoughts on this news article?

No Cookies | Herald Sun

Late last year one of these buildings was rejected due to the flight path restrictions. One of your colleagues, might've been Capt. Jackson, not sure, was spoken to on the radio. And gave a good explanation as to why the restrictions are in place.

I got the impression that it affected flight paths into MEL as well as Essendon. But in this article the fellow is refering only to Essendon.

I think it's been adequately answered by our air traffic controllers. The upshot is that a building does not have to be on the centreline of a runway for it to affect the operations of the airport.

In any event, most of these large buildings seem to be a form of cough for the developers....and in my opinion quite unnecessary.

 

[Skyhigh777]

JB, how do the flight crew decide who's doing radio duty? Most of the coughpit videos i've watched have the FO talking to ATC.

Thanks

 

[legroom]

The buildings affect the radar lowest safe altitude. When that building was under construction it affected the climb gradient of the Runway 19 SID that went straight ahead. It also increased the radar lowest safe altitude in the sector that affects left base or straight in approach for Runway 01 from 1900' to 2100' (that was daylight hours only). The CBD will affect the approach path of the new runway

Am I the only one who has difficulty following these sentences ?

Tech-professionals, please de-jargonise your words if possible so we mortals could keep up (JB is doing a sterling job in that regard).

My initial impression is that of some ATCs talking to each other - over my head.

Much appreciated

 

[jb747]

JB, how do the flight crew decide who's doing radio duty? Most of the coughpit videos i've watched have the FO talking to ATC.

The captain decides who is doing the flying...and the other bloke does the talking. Most times sectors are shared one for one.

 

[mjt57]

Hey JB, hang in there, mate. Turbulent times ahead, it seems...

 

[markis10]

Am I the only one who has difficulty following these sentences ?

Tech-professionals, please de-jargonise your words if possible so we mortals could keep up (JB is doing a sterling job in that regard).

My initial impression is that of some ATCs talking to each other - over my head.

Much appreciated

The buildings interfere with the radar altimeter (Radar altimeter - Wikipedia, the free encyclopedia - basically an altimeter that does not use air pressure to work) on the planes giving false readings as to height above ground (as opposed to height above buildings). As a result the aircraft have to fly higher. Buildings dont need to be inline with runways to be an issue.

There are some standards around that determine the Obstacle Limitation Surface for an aerodrome based on runways and approach paths, if a building penetrates that surface, it needs to be approved by Airservices Australia. The nitty gritty is here:

http://www.casa.gov.au/wcmswr/_assets/main/aerodromes/rpa/chap10.pdf

An approach adds its own surface, a typical OLS would look like this example:



In the case of Melbourne, the CBD is closer to Essendon than Tulla, so raising the height over the CBD planes must fly means a steeper approach to Essendon.

 

[mjt57]

Is JB still in LA? If so, looks like he may have an extended "layover"...

No Cookies | Herald Sun

I recall something similar happening to a QF aircraft in LAX a few years back.

 

[jb747]

Is JB still in LA? If so, looks like he may have an extended "layover"...

No Cookies | Herald Sun

I recall something similar happening to a QF aircraft in LAX a few years back.

It's happened for as long as aircraft have had wings. And I'm most definitely not in LA.....

 

[jukebox333]

It's happened for as long as aircraft have had wings. And I'm most definitely not in LA.....

Or at least for as long as there were two aircraft that had wings...

 

[anat0l]

Is JB still in LA? If so, looks like he may have an extended "layover"...

No Cookies | Herald Sun

I recall something similar happening to a QF aircraft in LAX a few years back.

It's happened for as long as aircraft have had wings. And I'm most definitely not in LA.....

Who tows the aircraft in and out of the hangar? Or rather, who has prime responsibility for the towing of the aircraft as such? The airline, the airport, or a contract ground service?

I guess the media can sink the boot into the airline, but who really will cop the blame and the bill?

 

[petercr]

You must have had a quick turn-around back home then... or are you just not in LA?That then springs to mind a question - who does the trans-American leg of QF108 /108? Is it the second crew onboard from Oz?