Ask The Pilot

[andmiz]

Vertically...no I don't think there's any consideration of it beyond the designers stage. Fore and aft is the most sensitive (by far) direction for any CofG load changes. Lateral is much less a consideration, and vertical...not at all.

JB, do you know if when they are flight testing the A380, if ballast tanks are loaded on just one deck, or distributed throughout? I would expect that there is a small vertical component involved in the CofG, which would need to be taken into account based on the AoA. Considering there are 3 decks, at the fore and aft limits, there would have to be a small consideration for the respective AoA which would narrow the available range.

 

[mjt57]

Speaking of CoG limits, cargo aircraft are high wing aircraft. Why don't they do that with all heavy passenger aircraft? Wouldn't that help with a more stable CoG? Or not?

Obviously the engineers have their reasons as to why they design aircraft the way that they do.

 

[por930]

Speaking of CoG limits, cargo aircraft are high wing aircraft. Why don't they do that with all heavy passenger aircraft? Wouldn't that help with a more stable CoG? Or not?

Obviously the engineers have their reasons as to why they design aircraft the way that they do.

The great majority of cargo aircraft are low wing, many of them converted from passenger types. See this...World's 50 largest air cargo carriers in 2014: FedEx leading the way - Air Cargo News

The very super heavy cargo guys are high wing, eg Antonov, and maybe high wing helps loading bulky cargo when the nose drops to the floor. Though the 747 cargo nose also lifts. Be interesting to see if any of the A380 become cargo carriers, though maybe logistics of handling such a big aircraft in the cargo areas may make them not popular

 

[jb747]

JB, do you know if when they are flight testing the A380, if ballast tanks are loaded on just one deck, or distributed throughout? I would expect that there is a small vertical component involved in the CofG, which would need to be taken into account based on the AoA. Considering there are 3 decks, at the fore and aft limits, there would have to be a small consideration for the respective AoA which would narrow the available range.

I don't know. I never saw any of the test aircraft.

 

[jb747]

Speaking of CoG limits, cargo aircraft are high wing aircraft. Why don't they do that with all heavy passenger aircraft? Wouldn't that help with a more stable CoG? Or not?

CofG is only fore/aft, so the wing position isn't a big factor.

High wing obviously works very well for the heavy carriers, but one major reason is simply that it makes for much easier structures for a roll through design. The wing structure is above the cargo area, not extending through it. It will make it easier to place the fuselage low to the ground, which is needed for ramps.

Aerodynamic stability is quite different, with the aircraft actually having an excess of roll stability, which is partially offset by anhedral on the wings (downward cant).

I wouldn't be surprised if the advantages that exist for cargo loading are countered by less efficient overall aerodynamics.

You also end up needing the wheels to be mounted on the fuselage, which reduces the track dramatically.

 

[jb747]

The very super heavy cargo guys are high wing, eg Antonov, and maybe high wing helps loading bulky cargo when the nose drops to the floor. Though the 747 cargo nose also lifts. Be interesting to see if any of the A380 become cargo carriers, though maybe logistics of handling such a big aircraft in the cargo areas may make them not popular

There was to be a cargo A380 variant, but Airbus scrapped it quite some time ago. I doubt that we'll ever see any conversions... there's airframes that I consider better suited (and you can buy just about any model from Boeing as a freighter).

Worth noting that the original design of the 747 was based on a failed proposal for a USAF heavy freighter. The C5 won.

 

[PaulST]

Worth noting that the original design of the 747 was based on a failed proposal for a USAF heavy freighter. The C5 won.

I remember reading that!

I suppose that there's a lot more 747 spare parts around thus making it far more attractive for a freight company where their bottom line is going to be paramount. You'd struggle to beat the versatility of the 747F too as you can even land them in Wollongong*!

*may not be able to takeoff, though.

 

[Feka742]

As my first post, I'd like to add my sincere thanks to JB, Boris et al for their contributions to this seemingly endless thread. It's made for a fascinating 881 pages of reading.

My question is probably targeted at JB but would welcome any insights. When QF first started up the QF27/28 route to SCL, it was pegged as an exclusively 744ER operation. Over time, however, non-ER 747s have increasingly appeared on the run and SCL has become one of the main destinations for the older 747s.

It seems that the benefit of operational experience has given QF more flexibility than initially expected. My question (applicable to all airlines) is what sort of 'lessons' can be learnt in operations that don't appear 'on paper' before the route is actually flown? Given QF's extended history with the 747 and 744, I would've thought they would know just about all there is to know.

The same applies with Qf7/8 (mainly when it was a 747 route) - reliability seemed to progressively increase as time wore on.

Thanks in advance.

 

[jb747]

As my first post, I'd like to add my sincere thanks to JB, Boris et al for their contributions to this seemingly endless thread. It's made for a fascinating 881 pages of reading.

My question is probably targeted at JB but would welcome any insights. When QF first started up the QF27/28 route to SCL, it was pegged as an exclusively 744ER operation. Over time, however, non-ER 747s have increasingly appeared on the run and SCL has become one of the main destinations for the older 747s.

It seems that the benefit of operational experience has given QF more flexibility than initially expected. My question (applicable to all airlines) is what sort of 'lessons' can be learnt in operations that don't appear 'on paper' before the route is actually flown? Given QF's extended history with the 747 and 744, I would've thought they would know just about all there is to know.

The same applies with Qf7/8 (mainly when it was a 747 route) - reliability seemed to progressively increase as time wore on.

The biggest lessons will be a mix of the real weather, and its effect on operations, and also ATC. Some airports are managed in such a way that delays are minimised, whilst others don't seem to handle the issues that crop up at all well. The company will adjust fuel loadings and sometimes timings in response to what they've seen. Payloads may be limited to allow for more fuel, or existing restrictions may be removed.

In a case where the overall diversion rate reduces (the Dallas 747), I'd expect that experience caused them to restrict the loads to allow a little more fuel. Sometimes a small amount can make a big difference.

In Dubai fog and dust have proven to be substantial issues. Not only have holding fuel loadings been increased, but many operations that were originally planned as 2 man crew are bumped to 3 to allow more flexibility.

An example from years ago on the Brisbane to Singapore 767 flight. This was programmed as a two man operation, under a set of rules that were more restrictive than normal for flight time extensions. It was found that carrying the maximum offered payload made the fuel load marginal...so crews either offloaded some cargo or risked a diversion. Under those particular rules, a diversion would almost certainly mean the crew would be out of hours. The issue was only with some particular aircraft though (the -200s) as they were much more weigh limited than the -300s. Solution was simply that the 200s would operate 3 man crew, whilst the -300s continued as planned.

 

[Feka742]

An example from years ago on the Brisbane to Singapore 767 flight. This was programmed as a two man operation, under a set of rules that were more restrictive than normal for flight time extensions. It was found that carrying the maximum offered payload made the fuel load marginal...so crews either offloaded some cargo or risked a diversion. Under those particular rules, a diversion would almost certainly mean the crew would be out of hours. The issue was only with some particular aircraft though (the -200s) as they were much more weigh limited than the -300s. Solution was simply that the 200s would operate 3 man crew, whilst the -300s continued as planned.

Thanks very much JB, very interesting.

Funny you mention SIN-BNE in this context - I experienced a diversion to CNS on this very route last year on a 747 operating with two crew. Wx (that didn't really eventuate at BNE in the end) saw the diversion called near ASP, before the crew ran out of hours and a replacement flown in. Around 8 hour delay in the end. Thin margins probably become a lot more so with a two-man 744 given the usual nearby alternates (OOL & MCY) can't accommodate the jumbo.

 

[jb747]

Funny you mention SIN-BNE in this context - I experienced a diversion to CNS on this very route last year on a 747 operating with two crew. Wx (that didn't really eventuate at BNE in the end) saw the diversion called near ASP, before the crew ran out of hours and a replacement flown in. Around 8 hour delay in the end. Thin margins probably become a lot more so with a two-man 744 given the usual nearby alternates (OOL & MCY) can't accommodate the jumbo.

Any reasonably long 2 man crewed flight can become problematic. You're up against a couple of limits. Normally 8 hours flight deck, which can be extended to 9, and 11 hours duty, which can go to 12. I guess that mostly sounds like a pretty normal day at work, but remember that it's also back of the clock, without any rest. The 747 flight time for the sector would be probably be around 7 hours, so there should be a reasonable margin. In most cases, the problem actually arises, when, after reaching destination and holding for a while, the aircraft is forced to divert. An early call to divert will limit the flight time, and might make continuation possible.

OOL isn't much of an alternate for a number of reasons. No parking, short runway, and not much in the way of navaids/approaches. Don't know anything about MCY.

 

[Dale Eastham]

As my first post, I'd like to add my sincere thanks to JB, Boris et al for their contributions to this seemingly endless thread. It's made for a fascinating 881 pages of reading.

My First post in this thread too, and would like to repeat what Feka said earlier - a truly fascinating read over the past few months (2-3 pages at a time, whenever I had a chance). There's so much to learn about the behind-the-scenes mechanics of commercial aviation. Flight tracker for one, has provided many hours of fascinated scrolling & clicking.

As I've read through everything though, one question has repeatedly come to mind when reading about the work schedules & loads of Boris, JB, etc. I work with a lot of shift workers (I'm not one), and a common theme amongst new staff is the difficulty their partners have in adapting to their sleep/wake/work cycles. How do the families of Domestic/ International pilots cope with this, or rather, how do pilots cope with being away for irregular & extended periods of time?

I know an air force pilot & have discussed with him over beers the trials & tribulations of having a young family (our kids are similar ages) & being away for work for longer periods of time.

Please note, I'm not expecting (or looking for) specifics here, but I could only imagine I would find it hard being away for long periods from my two little ones - how do pilots in general cope with/get around this?

Thanks in advance, and a BIG thanks to the professional pilots who contribute to this thread, it has genuinely been a really informative & interesting read.

 

[jb747]

As I've read through everything though, one question has repeatedly come to mind when reading about the work schedules & loads of Boris, JB, etc. I work with a lot of shift workers (I'm not one), and a common theme amongst new staff is the difficulty their partners have in adapting to their sleep/wake/work cycles. How do the families of Domestic/ International pilots cope with this, or rather, how do pilots cope with being away for irregular & extended periods of time?

I guess it varies with the family. Some handle it without any issues, whilst for others it's cause to either leave the industry, or get a new wife. I've even heard of a couple of wives who have delivered the ultimatum..."it's flying or me". Flying normally wins.

My son got used to always having two Christmas days, because I was never at home on the correct day. You miss every major school event, as well as most family ones. By the time you're senior enough to actually have those days off, the kids are adults, and nobody cares.....

On the positive side, on your days at home, you're generally left alone.

I know an air force pilot & have discussed with him over beers the trials & tribulations of having a young family (our kids are similar ages) & being away for work for longer periods of time.

My experience of the air force was that they had a much more regular home life than an airline pilot, and that's actually been an issue for some who leave to join the airlines.

Please note, I'm not expecting (or looking for) specifics here, but I could only imagine I would find it hard being away for long periods from my two little ones - how do pilots in general cope with/get around this?

Well, you do notice their growth when you've been away for a week. It's very hard on the wives when they have very young ones, but it's not the only job like that. On the other hand, and especially in long haul, you do get reasonable breaks between flights, so you're not just a weekend dad like most.

 

[Boris spatsky]

My experience of the air force was that they had a much more regular home life than an airline pilot, and that's actually been an issue for some who leave to join the airlines.

Pre 1999 (East Timor unrest) the Air Force mainly trained with very little operational deployments. Nowadays it is the polar opposite. I left the Air Force partly to get some normality to my life. When i was in the RAAF and flying, i was away about 8-9 months a year, every year (4-6 of those in the Middle East). When i was home i was either instructing in the sim, or night flying. To say i had a marriage was a facade as i never saw my wife. After we had our first kid and i was sent away for 6 months soon after she was born, my wife and i decided that enough was enough.

At least i get to see my family almost every day in the airlines - i never saw them when i was in the RAAF. No idea why my wife put up with it all - i am sure i wouldn't have!

 

[Boris spatsky]

As I've read through everything though, one question has repeatedly come to mind when reading about the work schedules & loads of Boris, JB, etc. I work with a lot of shift workers (I'm not one), and a common theme amongst new staff is the difficulty their partners have in adapting to their sleep/wake/work cycles. How do the families of Domestic/ International pilots cope with this, or rather, how do pilots cope with being away for irregular & extended periods of time?

I know an air force pilot & have discussed with him over beers the trials & tribulations of having a young family (our kids are similar ages) & being away for work for longer periods of time..

My wife is used to it as it has almost been 20 years now. The kids get upset when i go but we get great quality time together when i am home. The toughest gig is when you have really young kids - the strain on the spouse is unrelenting and i don't know how they do it. We get to go to work and have fun (most days!) and they don't. I don't know how they do it.

The roster helps as you can at least plan your month. The Air Force didn't have that (as you were on call every day of the year) so it was demanding. I missed the final Crowded House concert at the Opera House as i was called to fly whilst on the train into town!

Ultimately, aviation is a single person's game. Trying to find pilots on their first marriage that has lasted more than 5 years is like finding a needle in a haystack. (Thankfully, i am one of them)

 

[drross]

My wife is used to it as it has almost been 20 years now. The kids get upset when i go but we get great quality time together when i am home. The toughest gig is when you have really young kids - the strain on the spouse is unrelenting and i don't know how they do it. We get to go to work and have fun (most days!) and they don't. I don't know how they do it.

The roster helps as you can at least plan your month. The Air Force didn't have that (as you were on call every day of the year) so it was demanding. I missed the final Crowded House concert at the Opera House as i was called to fly whilst on the train into town!

Ultimately, aviation is a single person's game. Trying to find pilots on their first marriage that has lasted more than 5 years is like finding a needle in a haystack. (Thankfully, i am one of them)

Go Sir Boris the Needle

 

[RailFlyer]

Any reasonably long 2 man crewed flight can become problematic.

I'm sure this has been asked before, but how to you manage breaks with a 2 man crew on a 7 hour flights. Do you just informally zone out when nothing is going on for a few minutes until the radio chirps or something beeps? Or do you have periods where you hand over all responsibilities to the other pilot and go for a walk to the back of the plane or read something for a few minutes? Can't believe it is possible to concentrate (safely) without a break for 7 hours at a time, day after day, without going mad. I struggle to do 30mins work without checking to see if there is anything new on the internet which I must read for 5 mins!

 

[andmiz]

I'm sure this has been asked before, but how to you manage breaks with a 2 man crew on a 7 hour flights. Do you just informally zone out when nothing is going on for a few minutes until the radio chirps or something beeps? Or do you have periods where you hand over all responsibilities to the other pilot and go for a walk to the back of the plane or read something for a few minutes? Can't believe it is possible to concentrate (safely) without a break for 7 hours at a time, day after day, without going mad. I struggle to do 30mins work without checking to see if there is anything new on the internet which I must read for 5 mins!

The most typical break on any crewed flight, whether it's 2, 3 or 4 man, is to hand over duties to the other pilot (either flying or radio/paperwork duties) and get out of the seat, use the bathroom, go for a stretch, have a quick chat to the cabin crew, or whatever is needed to brighten up again. My typical one is just to get up and make myself a cup of coffee.
'Controlled Rest' is the other option, whereby you'll nominate a time period you'll be resting for (not exceeding 40 mins), request a wakeup/check call from the cabin, and you'll slide/recline the seat back and try to get a power nap.

 

[JessicaTam]

Are there no women on the flight deck?

 

[por930]

The most typical break on any crewed flight, whether it's 2, 3 or 4 man, is to hand over duties to the other pilot (either flying or radio/paperwork duties) and get out of the seat, use the bathroom, go for a stretch, have a quick chat to the cabin crew, or whatever is needed to brighten up again. My typical one is just to get up and make myself a cup of coffee.
'Controlled Rest' is the other option, whereby you'll nominate a time period you'll be resting for (not exceeding 40 mins), request a wakeup/check call from the cabin, and you'll slide/recline the seat back and try to get a power nap.

If you choose the 'controlled rest', do you stay on the flight deck or find a seat outside, assuming you have no rest areas in the flight deck area? If on the flight deck, wouldn't the PF give you a shake?
Does the modern flight decks have an attention monitor? By this I mean, every 30 minutes or so, a radio used, or some control on the flight deck has to be 'changed', or a warning sound starts, eventually becoming a whoop whoop etc.