Ask The Pilot

[petercr]

Are you sure that they weren't using one of these ...

Most reversers don't actually provide enough reverse thrust to safely push an aircraft back (and yes, I know it's often done on the MD90s and older 737s).

That must be some pretty awesome torque generated to shift up to 100, 000kg...

 

[Alanslegal]

Are you sure that they weren't using one of these SCHOPF PowerPush - Remotely Controlled Towbarless Pushback System - YouTube

Most reversers don't actually provide enough reverse thrust to safely push an aircraft back (and yes, I know it's often done on the MD90s and older 737s).

Here's the clip I recorded. I missed the initial stages but I am pretty sure that the push back was unassisted. At the time I was quite surprised to see it happening as I am so use to seeing a push back crew if a plane is departing from the gate, and in this instance I was like "is that plane leaving by itself?"

Vueling Airlines self pushback at Ibiza Airport 09/2013 - YouTube

 

[jb747]

That's a tight turn away from the gate. No assistance or push required. We used to do something similar with the 767s out of Cooly. You can see that the guidance lines are drawn for just that....

 

[markis10]

That's a tight turn away from the gate. No assistance or push required. We used to do something similar with the 767s out of Cooly. You can see that the guidance lines are drawn for just that....

767s from OOL, sigh, the good old days.

 

[dk4]

Thanks Alanslegal for the vid, I wonder if there is a cost advantage of doing away with some ground crew and equipment...interesting to see if TT & JQ think MEL T4 should have wider spaced gates to allow for turns like that?

 

[Alanslegal]

Thanks jb747.

 

[serfty]

FWIW, AA set up some gates at DFW specifically to enable their MD's to use reverse thrust to escape the gate, but soon went back to the tug for various reasons including a large amount of FOD.

REVERSE MD 80 - YouTube

 

[mjt57]

In the travel section of the paper the other day, the fellow from askthepilot.com, Patrick Smith gets a mention. He has a book, "coughpit Confidential", which to me looks like a condensed and readable version (readable is in book readable) of this thread.

I put it into my Kindle last night and started reading it. Every para I'm thinking, "yeah, JB has pointed that out...".

And as expected, the media cops a blasting for its sensationalist and often wrong coverage of matters aviation, and talks, as JB has done, about Passenger Exaggeration Phenomenon. (or words to that effect).

It must be frustrating for JB and his colleagues to read the misinformation and just plain bulltish that media trots out, particularly when the phrases "forced down", "emergency landing" and the dreaded "plummetted" word are used...

I would say that this book is a good read for those passengers who know little about aviation but have preconceived ideas on how it works and is a good companion for JB's "Ask the Pilot" thread.

I don't know if JB would agree with everything in it, though. Hopefully they'd not be too far apart in their thinking on matters commercial aviation.

And finally, this just in...

http://www.heraldsun.com.au/news/na...wo-qantas-planes/story-fni0xqrb-1226723614363

They show a photo of an A380 and what looks like a B777 or A330 (I can't tell) in the same shot with the caption that they're flying "close to each other".

 

[harvyk]

And as expected, the media cops a blasting for its sensationalist and often wrong coverage of matters aviation, and talks, as JB has done, about Passenger Exaggeration Phenomenon. (or words to that effect).

It must be frustrating for JB and his colleagues to read the misinformation and just plain bulltish that media trots out, particularly when the phrases "forced down", "emergency landing" and the dreaded "plummetted" word are used...

It's not just pilots that look to the media and shake their heads, there have been many times I've read articles on subjects I know about and decided that the research for that article was done at 5pm on a Friday over beers.

Once upon a time, journo's took pride in getting the facts straight before writing an article, these days they are happy to sprout out cough, provided they sprout out cough on a subject before their competitors.

 

[MEL_Traveller]

They show a photo of an A380 and what looks like a B777 or A330 (I can't tell) in the same shot with the caption that they're flying "close to each other".

sorry for getting OT... but I couldn't help the irony (of making things up) that you should know qantas doesn't fly 777s and it's a 767 anyway!!

 

[harvyk]

Well to get this back on topic, with TCAS events obviously they require action from the pilots, but are they considered a serious event, or more an event to log so that if a pattern emerges it can be dealt with?

 

[jb747]

In the travel section of the paper the other day, the fellow from askthepilot.com, Patrick Smith gets a mention. He has a book, "coughpit Confidential", which to me looks like a condensed and readable version (readable is in book readable) of this thread.

I put it into my Kindle last night and started reading it. Every para I'm thinking, "yeah, JB has pointed that out...".

And as expected, the media cops a blasting for its sensationalist and often wrong coverage of matters aviation, and talks, as JB has done, about Passenger Exaggeration Phenomenon. (or words to that effect).

It must be frustrating for JB and his colleagues to read the misinformation and just plain bulltish that media trots out, particularly when the phrases "forced down", "emergency landing" and the dreaded "plummetted" word are used...

I would say that this book is a good read for those passengers who know little about aviation but have preconceived ideas on how it works and is a good companion for JB's "Ask the Pilot" thread.

I don't know if JB would agree with everything in it, though. Hopefully they'd not be too far apart in their thinking on matters commercial aviation.

Patrick has been writing a blog, and books for quite a while. He had a section on Salon.com with the same title as this thread. It was less question and answer, but more weekly essay on whatever happened to take his fancy, or whatever was a current news topic. Overall a very good read.

When we originally started this thread, one of the main aims was to make it easy for people to ask questions about whatever happens to confuse them, and also to allow me a forum on which I could try to kill off some of the myths.

Our distaste for the media is almost total. Virtually everything that they write or show on TV is wrong. Simply made up gibberish to fill an otherwise empty piece of paper or time slot. It was refreshing recently to see the BBC 'Airport Live', as they made a real attempt to get things right. After QF30 I didn't know whether I should be stunned or amazed as I read about what I'd been involved with....and virtually all of it was so wrong as to make watching/reading a waste of time.

And finally, this just in...

No Cookies | Herald Sun

They show a photo of an A380 and what looks like a B777 or A330 (I can't tell) in the same shot with the caption that they're flying "close to each other".

They aren't very close in the image. In normal operations you get close enough to each other that you can heard the other traffic...when they pass 1,000' overhead. On busy routes you often have virtually simultaneous passes with traffic above and below.

Breakdowns in separation happen. Most are corrected before the TCAS takes any interest, and are more a breach of the standards than a real issue. If the TCAS becomes involved, it will initially come alive with a 'traffic' call, at which point you do nothing other than get ready to obey (most times you're already watching interesting traffic anyway). If it then commands a manoeuvre, it will always be in the vertical...you disconnect the autopilot and flight director and ensure the VSI is in the green as commanded by the TCAS. It can change its mind, so an initial climb could be converted into a descent, and it can handle multiple simultaneous threats (which is the main reason you might get a conversion). TCAS manoeuvres are very gentle...nothing violent is required.

 

[jb747]

sorry for getting OT... but I couldn't help the irony (of making things up) that you should know qantas doesn't fly 777s and it's a 767 anyway!!

It's a light twin. They're all the same really.....

 

[WheelieBagWanderer]

Hi JB,

Like others, a "thank you" from me on the time you take to reply to us on this thread.

I have a question on a windshear warning.

Flying into MEL last month on a Jetstar A320 we were on final approach on a VERY windy day and then the flight crew initiated a go-around maybe 20 seconds before touch down.

A minute or so later, the Captain came on the PA and said the go-around was due to a "windshear warning" and we would be attempting landing again in a few minutes.

Does the windshear warning come from some equipment in the flight deck, a message from ATC or another aircraft?

Also, with regards to a go-around, I would imagine things are a little busy in the flight deck once the decision to go-around has been made. Is ATC notified about the go-around prior to or after the go-around? ie Do you need "permission" to go-around or does it have to be a split decision? What if there's other low-flying traffic in the area? How is that taken into consideration?

Finally, once the go-around has started, does the FMC need to be re-programmed to get the aircraft on the ground again, or is the aircraft flown manually from go-around to landing as altitudes are generally low and there's (usually) only a few minutes between the go-around and successful landing?

Apologies if these questions sound a little naive, but during this whole process these things crossed my mind.

Thanks for answering all our questions once again!

 

[jb747]

I have a question on a windshear warning.

Flying into MEL last month on a Jetstar A320 we were on final approach on a VERY windy day and then the flight crew initiated a go-around maybe 20 seconds before touch down.

A minute or so later, the Captain came on the PA and said the go-around was due to a "windshear warning" and we would be attempting landing again in a few minutes.

Does the windshear warning come from some equipment in the flight deck, a message from ATC or another aircraft?

There are two different types of windshear warning system. There is a predictive system, which looks at the radar returns and their Doppler motion, and uses that to predict where windshear may occur. The reactive system looks at the accelerations that the aircraft is experiencing and when it speaks up, you're already in the windshear. Most airliners have both systems. So one says you'll be in it soon, and the other says you're in it now.

Also, with regards to a go-around, I would imagine things are a little busy in the flight deck once the decision to go-around has been made. Is ATC notified about the go-around prior to or after the go-around? ie Do you need "permission" to go-around or does it have to be a split decision? What if there's other low-flying traffic in the area? How is that taken into consideration?

ATC are told when you get a chance. They're quite low on the coughpit priority list during the initial part of a go around, especially if inspired by a windshear alert. They will see that you're going around, and as often as not will come up with a call such as 'I see you're going around, when able head XYZ'. You NEVER need permission for anything if you consider the aircraft could be in danger. Go around tracks are part of every approach. So, there is no 'request go around'...it's simply 'going around'.

Finally, once the go-around has started, does the FMC need to be re-programmed to get the aircraft on the ground again, or is the aircraft flown manually from go-around to landing as altitudes are generally low and there's (usually) only a few minutes between the go-around and successful landing?

A bit of dealers choice here, plus it varies by type. The Airbus will string the original approach back onto the route automatically, as long as you've selected TO/GA. The Boeings don't, but it takes us very few seconds to reload an approach. Many people keep a copy of the approach in a secondary route, and simply activating that route will bring it back. And if that's too hard, just listen to the radar vectors, and then look out the window....works just like a Cessna.

 

[johnrm]

JB. How about offset tracks on the busier routes for opposite direction traffic?

Patrick has been writing a blog, and books for quite a while. He had a section on Salon.com with the same title as this thread. It was less question and answer, but more weekly essay on whatever happened to take his fancy, or whatever was a current news topic. Overall a very good read.

When we originally started this thread, one of the main aims was to make it easy for people to ask questions about whatever happens to confuse them, and also to allow me a forum on which I could try to kill off some of the myths.

Our distaste for the media is almost total. Virtually everything that they write or show on TV is wrong. Simply made up gibberish to fill an otherwise empty piece of paper or time slot. It was refreshing recently to see the BBC 'Airport Live', as they made a real attempt to get things right. After QF30 I didn't know whether I should be stunned or amazed as I read about what I'd been involved with....and virtually all of it was so wrong as to make watching/reading a waste of time.



They aren't very close in the image. In normal operations you get close enough to each other that you can heard the other traffic...when they pass 1,000' overhead. On busy routes you often have virtually simultaneous passes with traffic above and below.

Breakdowns in separation happen. Most are corrected before the TCAS takes any interest, and are more a breach of the standards than a real issue. If the TCAS becomes involved, it will initially come alive with a 'traffic' call, at which point you do nothing other than get ready to obey (most times you're already watching interesting traffic anyway). If it then commands a manoeuvre, it will always be in the vertical...you disconnect the autopilot and flight director and ensure the VSI is in the green as commanded by the TCAS. It can change its mind, so an initial climb could be converted into a descent, and it can handle multiple simultaneous threats (which is the main reason you might get a conversion). TCAS manoeuvres are very gentle...nothing violent is required.

eavy
JB: How about offset tracks for lateral clearance for opposite direction traffic on the busier routes? Why do we have to have 1000 feet vertical and virtually no lateral? Thanks. (The thought of hearing passing heavy traffic scares me)!!

 

[jb747]

Re: JB. How about offset tracks on the busier routes for opposite direction traffic?

eavy
JB: How about offset tracks for lateral clearance for opposite direction traffic on the busier routes? Why do we have to have 1000 feet vertical and virtually no lateral? Thanks. (The thought of hearing passing heavy traffic scares me)!!

Offsets are used as a matter of course on some routes, but not within Australia. They are assigned by ATC within China, but their airspace is extremely constrained, as the military have control of most of it. Not used at all within Europe or the USA.

Like everything, it probably isn't as simple as it seems. Some airways are quite narrowly separated, and even a smallish offset may infringe the separation standards for an adjacent airway. Much of the time offsets are pointless, as you're either 'free tracking' or flying direct to a waypoint, and so aren't on an airway at all.

 

[defurax]

Hi JB,

You mentioned in a previous post that there is an alternative route to get from DXB to LHR going through the Saudi airspace. Would you have to advise the cabin crew not to serve alcohol whilst flying over the kingdom? I see that the current flight path passes over Kuwait, is it a "dry airspace"? I had never thought about that before until I saw the movie Argo (i.e no alcohol in Iranian airspace).

 

[jb747]

You mentioned in a previous post that there is an alternative route to get from DXB to LHR going through the Saudi airspace. Would you have to advise the cabin crew not to serve alcohol whilst flying over the kingdom? I see that the current flight path passes over Kuwait, is it a "dry airspace"? I had never thought about that before until I saw the movie Argo (i.e no alcohol in Iranian airspace).

Not something I've ever heard of. Dubai certainly isn't 'dry'.

 

[RooFlyer]

Not something I've ever heard of. Dubai certainly isn't 'dry'.

Neither is Saudi Arabia, once you get behind the walls of the compounds