Ask The Pilot

[jb747]

In that same vain, what would be the most brutal flight for you? Something like a SIN to MEL with a dawn arrival?

Individual sectors can be quite easy. They need to be looked at as part of an entire roster to get an idea of how hard, or easy, they really are.

Singapore/Melbourne, as a stand alone sector is quite easy on the body. It's not particularly long, and you get to Melbourne nice and early. Get three of them over a short period of time, as you can, and they're an entirely different matter. A single London trip was never that hard either, but after a few in a row, you'd be totally knackered.

One that I haven't done for a long time, but that I remember as being particularly painful, was Honolulu - Sydney. The timing was such that you were unlikely to get any sleep beforehand, and you rarely got any during the flight.

 

[jb747]

I caught a few times ex MEL but in March 2006 it flew out of Sydney.

Dubai via London and back through LAX

It was also known to go via Manila, but I don't think it was sold that way!

 

[flyer89]

One that I haven't done for a long time, but that I remember as being particularly painful, was Honolulu - Sydney. The timing was such that you were unlikely to get any sleep beforehand, and you rarely got any during the flight.

If the times are still about the same it leaves HNL mid morning and arrives early evening. I’ve done that one as a passenger several times and it’s one of the best flights when you are down the back. Same for the SYD-JNB. 13.5 hours But it’s all daylight. Arriving was I in fairly good shape. Return flight on the other hand....was considering making a noose!

 

[Quickstatus]

Aviators:
Would appreciate a comment about this altitude profile. Why didn’t the aircraft stay at cruise altitude for the majority of the flight. Same profile over the last few days.

DXB-NBO B777 EK721
The earlier EK719 also had the same profile
However the KQ311 and 305 flights had a normal altitude profile

 

[jb747]

If the times are still about the same it leaves HNL mid morning and arrives early evening. I’ve done that one as a passenger several times and it’s one of the best flights when you are down the back. Same for the SYD-JNB. 13.5 hours But it’s all daylight. Arriving was I in fairly good shape. Return flight on the other hand....was considering making a noose!

It's had many timings over the years. The variant I was thinking of arrived in Sydney very early am.

Flights were often made worse by having a domestic sector tacked on to the end. If you think those early morning flights have fresh crews, think again. The worst one that I can recall, was Singapore (departing about 6pm), Perth (departing about midnight), Melbourne (departing about 6am), Sydney. All technically legal, but there was no reasonable chance for a rest, even with an extra crew member. That particular sequence didn't last long, as a couple of Captains refused to depart Melbourne.

 

[jb747]

View attachment 142214

Aviators:
Would appreciate a comment about this altitude profile. Why didn’t the aircraft stay at cruise altitude for the majority of the flight. Same profile over the last few days.

DXB-NBO B777 EK721
The earlier EK719 also had the same profile
However the KQ flights had a normal altitude profile

FR24 doesn't show anything particularly unusual, though there are major gaps in the track. I expect that's its an anomaly in the tracking rather than reflecting what the aircraft did.

 

[mjt57]

Landing at high altitude - yesterday whilst watching the Mexican F1 GP, in the background I spotted an aircraft on what I presumed was finals for the local Mexico City Airport.

According to the stats it's around 7,300ft to 12,500 (highest elevation) according to Wikipedia.

How do you go landing at those sorts of altitudes? Must make for some interesting approaches, wouldn't it?

 

[jb747]

Landing at high altitude - yesterday whilst watching the Mexican F1 GP, in the background I spotted an aircraft on what I presumed was finals for the local Mexico City Airport.

According to the stats it's around 7,300ft to 12,500 (highest elevation) according to Wikipedia.

How do you go landing at those sorts of altitudes? Must make for some interesting approaches, wouldn't it?

Mexico is up around 10,000', and that is generally as far as the makers go with certifying the aircraft. The highest I've operated to is Johannesburg, which is about 5,000'.

Basically the air is thinner. The IAS for departure and arrival speeds is about the same, but because of the altitude difference the TAS is about 20% faster. As TAS is what the aircraft energy is based upon, it takes longer to accelerate, and longer to slow down. Braking will need to get rid of almost 40% more energy. Engines will generally produce less power. Even for the same 3º approach path, the higher TAS means that the sink rate will be faster. You'll need more flare and earlier, so it's easy to misjudge.

So, the aircraft is sloppier, behaves as if it's much heavier, and you've got less power, and greater need for long runways because of the higher energy levels. What could possibly go wrong?

 

[flyer89]

So, the aircraft is sloppier, behaves as if it's much heavier, and you've got less power, and greater need for long runways because of the higher energy levels. What could possibly go wrong?

Are there any particular special procedures for JNB? Could be irrelevant but in about 10 flights it’s always been FO sector to JNB and Captain sector home.

 

[JohnM]

Earlier this year I twice flew into and out of LPB (El Alto Airport, La Paz, Bolivia) which, at 13323 ft (4061 m), is listed as the fourth highest commercial airport in the world (List of highest airports - Wikipedia). Once was from LIM, so effectively from sea level; the other was an internal flight from Salta at about 4000 ft).

Aircraft were an A320 and a B737. On all days the weather was clear.

As a pax, I was not conscious of anything different from any other flight in the flying. After the information above, all the more reason to be in awe of the pilots.

 

[jb747]

Are there any particular special procedures for JNB? Could be irrelevant but in about 10 flights it’s always been FO sector to JNB and Captain sector home.

No particular procedures that I recall. They gave it to me as my first 'solo' trip after checking out in command on the 747, so it can't have been that hard.

There's no procedure that would have the FO flying into JNB. It's just the way it's working out. I suspect you'd find a bias in most of the sector pairs...it's simply at the whim of the Captain.

 

[Quickstatus]

The other occasion was during the A380’s early days. In that case it gave us law reversion to alternate II (meaning no automatics). The aircraft was a PITA to fly, because of the way the roll trim works (or rather doesn’t).

I think you have covered this in the past.
How
What was the easiest aircraft to fly manual in your experience?

 

[jb747]

I think you have covered this in the past.

What was the easiest aircraft to fly manual in your experience?

I guess we need to work out what you mean by ‘manual’. If it’s just a case of not having the autopilot engaged, then the A380 is the easiest, but neither the 767 nor 747 were at all difficult.

But, in the AB, for the automatics to be unavailable, you need to have had a law reversion. Firstly that means you’ve had a couple of failures, which in themselves can make life harder. But it also means the aircraft falls back to emulations of the behaviour of a non FBW aircraft...with all of the smarts removed. In particular, you lose access to any roll trim, which is a pain over long periods. Pilots are taught from day one of flying training to always keep the aircraft trimmed, so that if you let go of the controls, it will, at least over a short period, do nothing. You’re always fighting an aircraft that is out of trim.

 

[Captain Halliday]

Pilots, I’m interested in your thoughts on this flight profile and what would appear to be a turn back, though I acknowledge there may be other reasons?

The dips in the graph appear consistent with the apparent turn back.

 

[jb747]

Sorry, but there isn’t enough info in the trace to make any comments.

 

[clarmich]

Hello pilots, I have done a truckload of flying in the past month on both VA and QF, almost all on 73H. On landing, it seems that QF uses reverse thrust on their 737s for a substantially shorter period (on consistently so) than VA. Is there a standard protocol for reverse thrust or are a range of options available and each company operationalise their preference?

 

[AviatorInsight]

Hello pilots, I have done a truckload of flying in the past month on both VA and QF, almost all on 73H. On landing, it seems that QF uses reverse thrust on their 737s for a substantially shorter period (on consistently so) than VA. Is there a standard protocol for reverse thrust or are a range of options available and each company operationalise their preference?

Standard protocol is to crack the reversers immediately upon touchdown and then stow them approaching 60kts. There is a variation to this and it depends on the exit off the runway. If we're using SYD 16R I'll use reverse all the way to 60kts. If it's OOL 14 then I'll stow them earlier and roll through to K.

I'll cancel the reverse to the idle detent approaching 60kts and then once the N1 reaches about 25% or so I'll stow them completely. IMHO I think this makes for a smoother transition to taxi speed.

 

[jb747]

Hello pilots, I have done a truckload of flying in the past month on both VA and QF, almost all on 73H. On landing, it seems that QF uses reverse thrust on their 737s for a substantially shorter period (on consistently so) than VA. Is there a standard protocol for reverse thrust or are a range of options available and each company operationalise their preference?

The first thing to remember, is that there is very little, if any, reverse thrust. Modern airliner reversers only affect the fan air, not the flow from the core, so whilst the fan flow might generate some reverse, the core is still pushing you along. It does have a number of other beneficial effects though. Firstly it will disrupt any water on the runway, and it also helps to destroy the lift generated by the wings...both sit the aircraft down on the ground a bit more firmly. It cancels out the core thrust, but not a great deal more.

On the other hand, it uses a bit of fuel, and adds to the wear cycles on an engine. Some aircraft can also have vibration issues with flaps/slats that are exposed to the reversed flow.

Basically though, you will always select idle reverse. That causes the engine to translate into its reversed form. Power selection above that will vary from landing to landing. The technique is to pull the reverse levers up to the ‘interlock’. When the translation is complete, the levers will unlock, and you can select whatever power setting you want. You’ll bring the power back to idle reverse by 60-70 knots. Engines can remain in idle reverse down to taxi speed, so there’s no hurry to get to out. Even at idle, there is substantial forward thrust, so you want them to remain at least at idle reverse whilst you’re still braking.

 

[RooFlyer]

To this mug punter, 'pitot tubes' seem to come up as an issue relatively frequently when aircraft incidents occur and I understand that the 'issue' of malfunctioning pitot tubes is exacerbated when pilots are relatively inexperienced.

Given that pilots, as a group, seem to be getting less experienced ( due to expansion of the industry), are there any alternative technologies available or on the horizon to replace pitot tubes, or even the management of inconsistent data?

 

[defurax]

MH approach into MEL this morning looked a bit unusual. Is this a case of overshooting the ILS and turning back to catch it again?