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AviatorInsight

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Pilots thoughts on this!

Like JB said this has always been procedure. Coffee cups must have a lid on them and must be passed around the back of the pedestal. Some pilots are very adamant about this procedure

On the 777 there’s an extra cup holder next to the rear flight deck window. FAs will usually put them there if we were busy to take them.

I suspect those pilots who let the coffee go over the pedestal never saw Fate Is The Hunter.
 

jb747

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Eh. Seems like it was just another piece for him to make money on.
I'm told by someone who might know, that he's actually paid nothing. Which values the input quite accurately.

But not before he could get in a heart stopping story about a mate on the Mirage.
Which has a lot of relevance. In some world.
 

Saab34

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JB...I see the Qatar 380had a gear issue last night so dumped above Port Phillip, burnt some then returned, above MLW. I see they advised they were conducting an Auto land. Is this standard overweight landing airbus procedure?

I thought Autoland results in a firmer touchdown vs hand flying it. Which is not what you want in a MLW landing?
 

jb747

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JB...I see the Qatar 380had a gear issue last night so dumped above Port Phillip, burnt some then returned, above MLW. I see they advised they were conducting an Auto land. Is this standard overweight landing airbus procedure?

I thought Autoland results in a firmer touchdown vs hand flying it. Which is not what you want in a MLW landing?
Automatic landings are almost invariably very smooth, but a few hundred feet longer than manual landings. A manual landing at a weight over the max is to be avoided if possible.

The 380 differs quite dramatically from the likes of the 747 with regard to fuel dump. The 747 can dump almost all of the fuel. The only fuel that can't be dumped is from the feed collectors, which from memory, total about 6,000 kgs. Not much, anyway. The A380 can dump all of the fuel in tanks other than the mains. That means that there is always about 80,000 kgs which can't be dumped. So, if you dump all that you can, you'll still be over MLW, perhaps by as much as 50 tonnes. It actually doesn't matter. MLW is certified for a certain maximum impact rate, so as you exceed the max weight, the need for a really smooth touchdown increases. If you achieve that, there are no post landing requirements. Unless there was something else wrong with the aircraft, there wasn't even any real need to dump.

It will be interesting to hear (if we ever do) just what the issue was.
 
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jb747

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Are tail strikes always pilot error because of weight miscalculation or are there other reasons?
There are many reasons that tail strikes can occur. Some are own goals, whilst at other times Mother Nature is demonstrating her command of the situation.

In the case of weight miscalculation, they generally aren't small strikes, but often huge damage caused by dragging the tail for an extended period. That in turn happens because every bit of pitch you can get is needed to get off the runway. If the EK aircraft in Melbourne had used 1º less pitch, it would not have contacted the runway, but it would have hit the concrete barriers beyond the end. Damned if you do, damned if you don't.

Some aircraft are prone to it, and have either tail bumpers (767-300), or some form of flight control logic that attempts to limit, or warn about, excessive pitch. A normal 767 take off could have the bumper within 18" of the ground. You don't need much more attitude to convert that to zero.

A common own goal happens when a pilot goes too far in his attempt to give the passengers a smooth landing. As he holds off in the flare, not only is he wasting runway, but the aircraft attitude is progressively getting higher, and higher. As this technique is so poor, if he then compounds it by still ending up too high, and the aircraft ultimately thumps down on to the undercarriage, he's managed the perfect mix of too much pitch, and compressed oleos.

The actual lift-off, from the 'rotate' call to V2, is carefully choreographed to have the aircraft achieve a target pitch angle and speed at a rate that gets it clear of the ground, before the tail has a chance to impact the runway. If you hit the target attitude too rapidly, you will have a strike. New FOs (in particular) were prone to an error in crosswind take offs. As the aircraft could/would be hard to control laterally in the crosswind, they'd be anxious to get it into the air. That could lead them to too rapid a rotation at the rotate call.

In the sort of gusty conditions London is experiencing, there are a couple of wind variations that can lead to a strike. On arrival, a strong reduction in the wind, will lead to an increased sink rate, and that will have to be countered by pitch and power. If it's strong enough, you can run out of pitch and power...and height.

On take off, a sudden reduction in the wind, as you are rotating, may cause the aircraft to simply stop climbing away. If that attitude vs height (vs weight on oleos) progression breaks away from the normal, you're again in danger of a strike. A sudden increase in the wind, increasing the flow over the tail, will increase the elevator effectiveness, and increase the pitch rate. The upshot of all of this is that 'rotation' is not necessarily a simple case of pulling back on the controls. At times there can be some large changes right through the rotation.
 

p--and--t

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Two recent return to departure point flights in 24hours.

I'm guessing QF10 LHR-PER (B787-9) would have be full to the gills with fuel for the long trek to Perth but was back on the ground in around an hour.

QR905 MEL-DOH (A380-361) was going in circles for two or more hours dumping fuel.

Perhaps a pilot could explain the differences/reasons why the big time difference?
 

jb747

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Two recent return to departure point flights in 24hours.

I'm guessing QF10 LHR-PER (B787-9) would have be full to the gills with fuel for the long trek to Perth but was back on the ground in around an hour.

QR905 MEL-DOH (A380-361) was going in circles for two or more hours dumping fuel.

Perhaps a pilot could explain the differences/reasons why the big time difference?
787-9 max landing weight is about 195,000kg. Max take off, about 254,000. So if you took off at max weight, you'd need to get rid of 59,000 kg of fuel. I'd expect that to take about 30 minutes.

380 max take off 569,000 kgs, and max landing weight of 391,000 kgs. That's 178,000 kgs that you need to get rid of to reach max landing weight. But, you can't jettison the fuel in the main tanks, which would be roughly 70-80 tonnes. So, basically 100 tonnes that you can dump, at 2,400 kgs/minute. In round figures 40 minutes. But, at the completion of the dump, you're still going to be well over max weight. You are burning fuel during the period of the dump, and hopefully, you won't have arrived at the dump point without having gone through 10 tonnes or so, but you'll still be somewhere around 440 tonnes. You can leave the gear down, and fly around for a couple of hours in a high drag configuration, or land overweight. As Qatar had some form of gear issue, he would seem to have chosen the latter option. Personally, if the gear were correctly indicating down, I don't think I would have dumped at all, but that's very much the crew's choice.

The maths vary quite a bit depending upon that actual zero fuel weight. A flight out of LA to Oz, could probably dump about 120 tonnes. The lower the zero fuel component, the greater the amount you can dump.
 
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NM

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Personally, if the gear were correctly indicating down, I don't think I would have dumped at all, but that's very much the crew's choice.
How many times did you dump in your career? Many times you had to make a decision and chose to dump or not dump?

Did all aircraft types you flew in your QF career have dump capability - thinking about all variants of 767, 747SP if you flew it? Was fuel dump capability an option on some of those aircraft types or a standard feature?

What about military types that you operated? Any dump/jettison capability on any of them and did you ever need it?
 

jb747

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How many times did you dump in your career? Many times you had to make a decision and chose to dump or not dump?
I can only recall dumping twice. Once when I was bringing a TA-4 into Mascot, and we were carrying a load of inert ordinance for an open day. We had very little ability to fit in with ATC, so we arranged to carry a bit extra and to then dump as necessary to make the landing time they gave us. The other occasion was QF30, where we dumped about 50 tonnes.

Ah, just thought of another one. I was paired to do a session of dogfighting with another pilot, who was rather prone to cheating. He was the lead, and decided to give himself the single seater, and to give me the TA-4. The single was a lot nicer. Lighter, turned better. So I quietly dumped about a thousand pounds when I figured he wouldn't be looking. Not very ecologically sound, but it evened the playing field. He never did work out how I got the trainer to turn so well.

Did all aircraft types you flew in your QF career have dump capability - thinking about all variants of 767, 747SP if you flew it? Was fuel dump capability an option on some of those aircraft types or a standard feature?
Macchi could dump the fuel in the tip tanks.
A-4.
747, all variants
767-300, but not the 200
A380

I suspect it was an option on the 767.
 
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Aus ATC

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The actual lift-off, from the 'rotate' call to V2, is carefully choreographed to have the aircraft achieve a target pitch angle and speed at a rate that gets it clear of the ground, before the tail has a chance to impact the runway. If you hit the target attitude too rapidly, you will have a strike.
While understanding that V1, rotate, and V2 speeds are calibrated for the conditions, actual weight, etc, is there any benefit in delaying the rotation to reduce likelihood of tail strike - given in most cases, even heavily laden, there still seems to be plenty of runway remaining after the takeoff point?
 

AviatorInsight

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An article in the paper today about jet streams and a BA B744 breaking “the sound barrier”. Well, that’s how the lead in went.
comments, JB, AI?

Totally fake news. Perhaps its ground speed may have been that quick yes. But breaking the sound barrier? No. It’s all about indicated airspeed not groundspeed.

Also, the amount of fuel required to break Mach 1 is intense. Think why Concorde needed afterburners.

Fastest I got to breaking the sound barrier was Mach .895 (777).
 

RooFlyer

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An article in the paper today about jet streams and a BA B744 breaking “the sound barrier”. Well, that’s how the lead in went.
Just noting that the article referred to didn't say that the BA plane went supersonic or that it broke the sound barrier :) and it explained the difference between ground and air speed (maybe not perfect, but comprehensible in layman's terms).

A plane has broken the subsonic speed record.
...

While that flight made headlines when it broke the record for the fastest subsonic crossing, it didn't break the sound barrier. Down on the ground, its top speed of 1327 km/h would have felt faster than the speed of sound, which stands at 1236 km/h, but the plane was already tangled up in a strong push of air from the jet stream, meaning the dial in the cockpit likely hovered closer to 1054 km/h.
 

jb747

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Just noting that the article referred to didn't say that the BA plane went supersonic or that it broke the sound barrier :) and it explained the difference between ground and air speed (maybe not perfect, but comprehensible in layman's terms)
Perhaps, but this article has appeared in many places, and almost invariably, the word supersonic appears...clickbait. It was all about a really strong, and long lasting bit of wind. Which also describes the article.
 

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