Ask The Pilot

[andmiz]

For "normal" routine ops (eg. landing after LAX-MEL or SIN-MEL say, and not "emergency" landing), what would be the minimum landing distance required for the 777?

(I realise specifics around max landing weights versus "typical" etc will come into it).

Using rounded numbers, a landing weight of 224 tonne (max landing is 251T), landing distance is 1900 meters (using autobrake 3). At that weight, runway 27 in MEL is possible but only at autobrake 4 and only when dry. 235 tonne has been the highest landing weight into MEL I've seen over the last few days but averages around 225 for HKG-MEL.

Lots and lots of variables, but to generalise 2200-2400 meters would be a reasonable, normal routine distance required.

 

[andmiz]

Do freighter pilots tend to try and avoid weather systems in the cruise as much as airliners pilots (carrying PAX)? I'm asking because I saw that QF and Eva Air aircraft clearly avoided some weather while the FedEx aircraft flew straight through it.

Generally yes, or at least we do. Bouncing around in turbulence sucks just as much for pilots as it does for passengers. It spills our coffee. Without being there and seeing it with your own eyes, it's hard to specifically know why Eva/QF manoeuvred around the weather and Fedex didn't. For starters, were they flying at the same level? What part of the world were they flying (sometimes local knowledge helps). Maybe they had a different expectation of what was ahead, or the different aircraft type led to a different onboard experience.

 

[jb747]

JB
Any reason why ULH flights in A380 or 777 don't use R27 at Melbourne for landing?

I noted last week the first time I have seen a long haul land on 27 in a while, (Qatar DOH-MEL) when 34 was an operational runway also.

I have heard on ATC before Etihad A380 and Emirates A380 pilots refuse 27 and will hold until 34 was available (Emirates even said they would head to SYD!)

I assume it's all to do with weight and landing distances/weather etc?

Using normal assumptions for weather and weight, the calculations give a margin of 86 metres. That's about 500 metres less than I will accept without some form of overriding emergency. Basically, it's too short. Beyond that, there's a nice long one nearby. Plus, it's almost never into the wind...

ULR pilots have very likely had little to no sleep in the past 20-30 hours. Keeping it as simple as possible is their aim.

 

[jb747]

Do freighter pilots tend to try and avoid weather systems in the cruise as much as airliners pilots (carrying PAX)? I'm asking because I saw that QF and Eva Air aircraft clearly avoided some weather while the FedEx aircraft flew straight through it.

The image you've used is vertically derived...satellite looking down perhaps. All three of the aircraft have different types of radar that is looking at the weather from the side. It's just as likely that all of the images are quite different. Unless you have their radar images, I can't make much of a call. It doesn't look all that bad, and I'll bet there's a gap where Fedex is.

 

[defurax]

Generally yes, or at least we do. Bouncing around in turbulence sucks just as much for pilots as it does for passengers. It spills our coffee. Without being there and seeing it with your own eyes, it's hard to specifically know why Eva/QF manoeuvred around the weather and Fedex didn't. For starters, were they flying at the same level? What part of the world were they flying (sometimes local knowledge helps). Maybe they had a different expectation of what was ahead, or the different aircraft type led to a different onboard experience.

The image you've used is vertically derived...satellite looking down perhaps. All three of the aircraft have different types of radar that is looking at the weather from the side. It's just as likely that all of the images are quite different. Unless you have their radar images, I can't make much of a call. It doesn't look all that bad, and I'll bet there's a gap where Fedex is.

Thanks. I knew my example would have many limitations, but it was just a way to illustrate my question as to if pilots were behaving a bit differently in regard to weather depending on carrying humans or freight.

 

[Franky]

(Just recalled a flight on which there was no doubt...probably the first time I was ever hit too. In an A4G, off the coast near Nowra, towing a target for the ships.)

Three of the ships I served on, Parramatta 65-66, Vampire 67-68 and Swan 73-75 were involved in workups out of Jervis Bay that included shoots on a towed target. We may well have been hurling up 4.5 shells in your direction at some stage of your Naval career.

 

[jb747]

Three of the ships I served on, Parramatta 65-66, Vampire 67-68 and Swan 73-75 were involved in workups out of Jervis Bay that included shoots on a towed target. We may well have been hurling up 4.5 shells in your direction at some stage of your Naval career.

I was in the RAN from 73 to 85, but my A4 time was only the early 80s. I was originally a Seaking Observer. So you never threw any shells my way, but I may have delivered your mail.

DEs hardly ever damaged the target. DDGs did much better. FFGs every time. CIWS was really scary, especially if you saw it tracking the aircraft.

 

[Franky]

I was in the RAN from 73 to 85, but my A4 time was only the early 80s. I was originally a Seaking Observer. So you never threw any shells my way, but I may have delivered your mail.

DEs hardly ever damaged the target. DDGs did much better. FFGs every time. CIWS was really scary, especially if you saw it tracking the aircraft.

As CapSec on the last two ships, we always looked forward to mail drops!

 

[jb747]

Here you go then...

 

[Major]

I was at a Combined Colleges Demonstration on the range at Puckapunyal in 1980. There were a couple of A4's throwing ordnance from low level onto the range.

It was quite spectacular. This may have been before your conversion

 

[jb747]

I was at a Combined Colleges Demonstration on the range at Puckapunyal in 1980. There were a couple of A4's throwing ordnance from low level onto the range.

It was quite spectacular. This may have been before your conversion

The fire power demo. I never flew it, but watched some very heavily laden aircraft head down there a few times.

 

[Franky]

Here you go then...
View attachment 96185

Thanks - nice pic - typical Tasman Sea weather out thru the heads. Must have been time for Admiral's Inspection with the crew on deck in No 6s. Was an interesting first twelve months on her with the inimical Adrian coughmins as CO. An older Type 12 in the background with the LWO2 on top of the mast, which made for awful sea going conditions. Swan and Torrens were the first two to have it lowered to the superstructre, and along with stabilisers fitted, made things much more comfortable.

 

[jb747]

I don't recall the reason, but virtually the entire fleet was out in JB that day. I caught a ride in a Iroquois just to have a look.

Adrian coughmins. Now there is a name from the past. I worked for him twice, in Canberra in 1977, and when he was in charge of the DDG group in 1981. He helped my career, but not everyone could say that. Sadly he died quite young.

 

[Major]

When you have to stop on a taxiway what is involved in moving the aircraft again ? In a car you simply make sure it's in gear and put your foot on the accelerator. I would think there is more to it than that,

 

[AviatorInsight]

When you have to stop on a taxiway what is involved in moving the aircraft again ? In a car you simply make sure it's in gear and put your foot on the accelerator. I would think there is more to it than that,

It's actually a lot simpler than you think:

1. Park brake off.
2. Add some thrust (depending how heavy you are, sometimes just the residual thrust may be enough to get going again).

 

[jb747]

When you have to stop on a taxiway what is involved in moving the aircraft again ? In a car you simply make sure it's in gear and put your foot on the accelerator. I would think there is more to it than that,

Whilst AVInsight's answer is correct, there can be a bit more to it, especially in a very large aircraft.

Basically, once you release the brakes, the aircraft is free to roll. In most cases the land is flat, and, ignoring the effect of the engines for a second, the aircraft will stay put. But, there are many places where the land is less flat than it might appear, and then the aircraft will start to roll of its own accord. Tullamarine is full of such ups and downs. Now, this is convenient if you happen to be pointing down slope, but an aircraft is just as capable of rolling backwards as forwards. We don't have 'hill start' on our braking system. If an aircraft is allowed to roll back to any extent, touching the brakes to stop the motion could potentially lift the nose gear off the ground. Beyond that, you can't see behind you, nor is there always a vast amount of space.

The engines also take appreciable time to spool up from ground idle. We don't need much power to taxi. You'll normally need something in the order of 8%-10% to get an A380 rolling (break away power), and then you can pull them back to idle, once it has started to move. But, going from the 3-4% of ground idle up to that 8% takes a number of seconds. And during that time, if you've released the park brake, and are no longer on the pedals, then you'll have set yourself up to roll with the slope. So, push the power up a bit...and release the brakes once the engines are actually accelerating.

Idle thrust is almost always enough power to keep an aircraft moving once under way. As often as not, you need to brake every now and then to keep the speed low. At corners though, the aircraft will slow down, so generally you lead them with a little power. Tight (i.e. 90º) corners are often best handled with a little asymmetric power, which both keeps the aircraft moving and helps the turn. We're talking single digit percentages though. BTW, the A380 power display is a percentage of full power, not a percentage of RPM.

At the other end of the flight, when the aircraft is light, idle power is normally enough to start it moving, so you don't need 'break away' power...unless you're in a hurry.

 

[jb747]

Roster changes....

I was supposed to start a Dubai/London trip last night, but have come down with a cold (man flu), so I have lost that trip. Depending upon whenever I manage to shake this off, it may be replaced, or it could turn into a bunch of standbys. So, that has the effect of throwing the next couple of weeks into the lap of the gods.

Beyond that, I've swapped the trip that I had starting on the 4th of June for the same thing a couple of days later.

6/6 QF9 MEL-DXB
10/6 QF1 DXB-LHR
12/6 QF10 LHR-DXB
14/6 QF10 DXB-MEL

 

[Quickstatus]

How does the airline replace a captain at short notice in a foreign port?

 

[jb747]

Well, according to some, they just ask any bus driver.

Most rosters a built with some fat in them. This isn't the company being nice and giving us good slips. It's all about being able to replace someone, by moving everybody forward by a flight or two, until the hole is plugged.

In this case, I was still at home, and it went to the standby. According to FR24, he was pretty much on time, and got a straight in approach at Dubai, which is pretty much unheard of.

 

[flyingfan]

I was supposed to start a Dubai/London trip last night, but have come down with a cold (man flu), so I have lost that trip.

I hope you get better soon.

How well does a pilot have to be to operate a flight? Does some measure of coughing/a headache begin to rule you out? I'd imagine consciously or otherwise, there are considerations of being out of position and knock-on effects particularly if you're at a distant port, company measures notwithstanding?