Ask The Pilot

[jb747]

When selecting various degrees of flaps during the periods when they are not fully retracted, do the controls automatically adjust the slats too? Can flaps and slats be controlled separately if required? When might this happen?

On older aircraft the leading and trailing edge devices could be controlled separately. Alternate modes of operation may still operate that way. But, normally, we just move the flap lever to a setting and the control is automatic.

Flaps are the devices at the trailing edge of the wing. They increase the curvature of the wing and in some cases also extend in such a way that the wing area is increased. They provide more lift and more drag.

At the leading edge of the wing you can have either leading edge flaps (747) or slats (380). A slat is a panel that does nothing other than create a large slot, through which air flows to help keep the boundary layer of air attached.

A flap increases the lift, but it will also decrease the angle of attack at which the wing stalls. A slat does little to the lift directly, but the slot will cause the wing to stall later, and at a greater angle of attack (and so generate more lift). On the airliners, slats are controlled, but on some aircraft (the A4G for instance) the slats were held in by air pressure and could extend as the flows changed. During the preflight, you could just push them in with one hand.

 

[Flashback]

There's a statement on MH's website that they're unable to allow checked baggage on their flights to AMS & CDG which are serviced by a 777. Originally LHR was included, but that has since been removed. LHR is serviced by an A380.

Mentions it's due to a combination of headwinds, needing to take a different route, etc. Is there more to this than meets the eye?

 

[Shamrock55]

Any commercial pilots like to fly GA in their spare time? I have 15 hours in Piper Tomahawks and unfortunately failed my Class II medical due to a useless left eye so will never fly solo, but often wondered if you commercial guys ever walk into your local aeroclub and rent a 182 or something for some hand-flying fun?

 

[smeacs]

What do you do about a tailpipe fire?

 

[por930]

What's interesting from that is if an adult is taken to be 87kg and I assume that's including cabin luggage, I'm 23-25kg heavier than that, or a staggering 26.4-28.7% over! Might not be an issue on big jets but how is that going to affect smaller aircraft like CRJs, Dash 8s and ATRs?

I seem to recall on one of those aircraft accident shows that an ATR or some thing like this had an accident due to many pax were miners returning with lots of safety protective clothes in one of their bags and personal tools in another and the aircraft was grossly overloaded.

When we used to run air charters from Mount Isa to one of the copper mines, we always used to trott out the scales and account for every one and their bags. On several occasions we would off load bags. Indeed, in summer, the daily Boeing into/out of Isa would often offload bags and restrict pax numbers as too hot for take off.

 

[torks]

Hi JB & others,

Thanks for the time spent answering questions here. I've spent the last month or so enthusiastically reading the whole thing.

I've just seen that today Qantas sent a 5th engine on their 747 over to Johannesburg.

Is there any special training for the pilots for doing this or is it just a matter of adding a note to your pre flight briefing. Also from the picture in the Qantas press release (sorry I can't link to it) you can just about see through the engine. Have the engineers removed parts so that they aren't damaged by spending 14 hours blowing in the wind?

Thanks for all your time.

 

[drross]

Hi JB & others,

Thanks for the time spent answering questions here. I've spent the last month or so enthusiastically reading the whole thing.

I've just seen that today Qantas sent a 5th engine on their 747 over to Johannesburg.

Is there any special training for the pilots for doing this or is it just a matter of adding a note to your pre flight briefing. Also from the picture in the Qantas press release (sorry I can't link to it) you can just about see through the engine. Have the engineers removed parts so that they aren't damaged by spending 14 hours blowing in the wind?

Thanks for all your time.

welcome to AFF torks. It's a really interesting forum

 

[Boris spatsky]

On the topic of fuel saving over a fleet year (vs the tiny saving on one flight), after landing a 4 engine aircraft, why aren't 2 engines shut down after exiting the runway (to save fuel)? Or are they and pax just don't notice?

I guess it could equally apply to 2 engine aircraft (shut down 1) but the asymmetric thrust I guess would be a reason? Again, possible but perhaps not a good idea?

We routinely shut down one of two engines after landing in the short haul world, but it depends on a number of factors. There are specific rules for some airports, and even rules for specific parking bays (eg single engine might be disallowed due to an uphill bay - restarting an engine or using excess power to get up the hill negates the benefit in the first place.)

We also need a serviceable APU and hydraulics and always have to shut down one side over the other due to the hydraulic arrangement of the aircraft.

 

[jb747]

There's a statement on MH's website that they're unable to allow checked baggage on their flights to AMS & CDG which are serviced by a 777. Originally LHR was included, but that has since been removed. LHR is serviced by an A380.

Mentions it's due to a combination of headwinds, needing to take a different route, etc. Is there more to this than meets the eye?

You'd have to ask MH. I'm as perplexed as you.

 

[jb747]

Any commercial pilots like to fly GA in their spare time? I have 15 hours in Piper Tomahawks and unfortunately failed my Class II medical due to a useless left eye so will never fly solo, but often wondered if you commercial guys ever walk into your local aeroclub and rent a 182 or something for some hand-flying fun?

There are many airline pilots who still fly GA. One of the blokes I flew with recently flies a whole range of warbirds including the Mustang and Spitfire. The Russian Roolettes formation team is mostly made up of airline people flying their own aircraft. A few even have GA businesses. And HARS has a few airline people in its ranks.

But...the majority are like me, and only fly for work. I wouldn't rent a 182 to me...the last light aircraft I flew was in 1985 (a CT4).

 

[jb747]

What do you do about a tailpipe fire?

Discontinue the automated start. Initiate a manual start, but don't select the fuel to run. That has the effect of motoring it, and hopefully blowing any burning fuel out the back.

Call the fire services.

 

[jb747]

I've just seen that today Qantas sent a 5th engine on their 747 over to Johannesburg.

Is there any special training for the pilots for doing this or is it just a matter of adding a note to your pre flight briefing. Also from the picture in the Qantas press release (sorry I can't link to it) you can just about see through the engine. Have the engineers removed parts so that they aren't damaged by spending 14 hours blowing in the wind?

It's quite a neat arrangement, and both loading and unloading happen in only an hour or two. There's an internal shroud which will stop the engine from being rotated in the breeze.

There's no particular training for it. Just a single page in the ops manual, and about three in the performance manual.

The ops manual basically says that there is a switch in the electronics bay that the engineers will need to move to tell the FMCs and air data computers about the pod. The ADCs will use new (reduced) limits for speeds, and the FMC will switch to a program that reflects the additional drag and performance penalties. The performance manual gives a heap of limitations, but speed is reduced to .78 mach. All maximum weights are reduced, and there's discussion of trim settings to offset the yaw.

I only carried a pod once, way back around 1990. It was an engine for a DC10 which had been overhauled in Sydney. It was noticeable, but not dramatically so.

 

[Flashback]

It's quite a neat arrangement, and both loading and unloading happen in only an hour or two. There's an internal shroud which will stop the engine from being rotated in the breeze.

There's no particular training for it. Just a single page in the ops manual, and about three in the performance manual.

The ops manual basically says that there is a switch in the electronics bay that the engineers will need to move to tell the FMCs and air data computers about the pod. The ADCs will use new (reduced) limits for speeds, and the FMC will switch to a program that reflects the additional drag and performance penalties. The performance manual gives a heap of limitations, but speed is reduced to .78 mach. All maximum weights are reduced, and there's discussion of trim settings to offset the yaw.

I only carried a pod once, way back around 1990. It was an engine for a DC10 which had been overhauled in Sydney. It was noticeable, but not dramatically so.

... and all this can be done without telling passengers they can't check in any baggage! Fancy that!

 

[Awesom Andy]

... and all this can be done without telling passengers they can't check in any baggage! Fancy that!

The other time when they went to the US with that, they simply told Y pax they can't check in (the baggage AND themselves).

 

[anat0l]

... and all this can be done without telling passengers they can't check in any baggage! Fancy that!

They did have to add a few hours on top of the flight time via a convenient fuel stop. Lucky things must have went smoothly; SYD-JNB is no short flight, so the crew could have been at risk of timing out, unless (very unlikely) they were / were ready to switch out crews at PER.

 

[flychrisfly]

There's a statement on MH's website that they're unable to allow checked baggage on their flights to AMS & CDG which are serviced by a 777. Originally LHR was included, but that has since been removed. LHR is serviced by an A380.

Mentions it's due to a combination of headwinds, needing to take a different route, etc. Is there more to this than meets the eye?

I saw something somewhere that explained that MH were avoiding Iranian airspace for security reasons instead flying over Egypt to their European ports. The wind and the length of their routing led to the weight limitations. I believe (could well be wrong here) that this routing has since been adjusted to reflect MH's changed security assessment of the area. As I understand it QF and others currently fly over Iranian airspace. Perhaps, understandably, MH is a bit more jittery about some locales!

 

[eric2011]

I only carried a pod once, way back around 1990. It was an engine for a DC10 which had been overhauled in Sydney. It was noticeable, but not dramatically so.

Sorry JB, was that a DC10 engine which you carried on a 747 and if so, are the mounting points on the underneath of the 747 wings universal

 

[jb747]

Sorry JB, was that a DC10 engine which you carried on a 747 and if so, are the mounting points on the underneath of the 747 wings universal

I think the engine we carried was a CF6. At the time, QF didn't own any 747s with that engine, so I assume it was a kit that allowed carriage of all three of the engine models. I think that it was only the RR and Pratt engined aircraft that could carry the pod, though that may be an ER thing. Manuals don't say much....

 

[Mogul]

Are there any other aircraft that have the ability to carry an extra engine like the 747.

 

[mjt57]

On approach into MEL on Friday (VA B737) the guys up front were constantly applying and reducing thrust. I've not normally seen this. The approaches normally are fairly smooth and constant. There was also a bit of turbulence too as we descended (we tracked in from SYD over what appeared to be Eildon and other areas north of Melbourne). Would that have affected the aircraft's speed?