Ask The Pilot

[jb747]

In a recent air crash investigators it mentioned not all commercial aircraft have the ability to dump fuel. What sort of aircraft can't, is this a by design or sold as a optional extra?

Having never bought an aircraft, I can't say what the options list looks like.

The 767-200s couldn't dump fuel. That meant that they had to be able to achieve all of the certification requirements without that ability. It wasn't an issue. The aircraft could achieve all of the required performance marks, even engine out, at max weight. Even the A380s have a limited dump ability...you can't get rid of the last 80 tonnes or so, which means you can never dump to max landing weight after a heavy take off. But, you can land at any weight, right up to the max T/O weight, if you need to.

 

[jb747]

....but on a wide-body like the B747, its MTOW is 447.7 tonne and MLW is 346.0 tonne

Interesting weights, that I'm not familiar with. What version...747-800F?

The 747ER was 412 and about 275.

The A380 is 569 and 391.

 

[jb747]

Well, having given Melbournian a heads up about some runway works on 16 in Melbourne....guess who got caught out...by exactly the issue I predicted.

The A380 can't land on 27 as a matter of course. If the runway is wet, or there is any downwind, it won't be possible at all. It's marginal unless there is a substantial westerly wind, and normally you'd never land on it unless the wind exceeded the crosswind limits for landing on 34/16. The numbers today all came up orange on the application...so no go.

Runway 16 has a CAT III ILS installation, which allows landings in fog. But, at the moment, the 16 ILS is out of service, and the runway threshold is displaced by 360 metres, whilst the lighting system is being replaced with LEDs. The problem is that that means that there is no precision approach available for heavy aircraft (in particular the A380) whilst this work is going on. The alternative approaches to 16 are all non precision, and drop you off at about 500 feet above the ground...which is normally quite adequate, even with the displaced threshold.

This morning we saw patchy low cloud down to 200 feet, with the cloud base below the alternate criteria. So, that basically meant that you needed a full alternate (i.e. one that you carry all the way to the ground), plus it also meant that there was a substantial chance of any individual approach (to 16) not being visual that the minima, and having to go around. Sometimes carriage of Avalon as the alternate might fix the legalities of this, but today that was also below the criteria.

We watched this all night, and at about 150 miles from Sydney decided that it was not going to miraculously improve, and ducked in for a splash and dash (or as close as we could get to it). Arrived about 90 minutes later, and on the approach on to 34 became visual about 100 feet above the minima. Of course, the day didn't look too bad to those on the ground, so we heard the standard grumbles. If I could have continued safely I would have done so, but it simply was not prudent. This was the 38th time I've done the sector, and the first diversion.

 

[Quickstatus]

Everytime I fly the 94, I hope it diverts to SYD.

Not all of your passengers will be grumpy. There will usually be a few whose final destination is your divert.

Did you let any passengers off?

 

[jb747]

Everytime I fly the 94, I hope it diverts to SYD.

Not all of your passengers will be grumpy. There will usually be a few whose final destination is your divert.

Did you let any passengers off?

No...none. The CSM was expecting to be asked, but nobody wanted to get off. Having too much fun I guess.

Grumbles more that grumpy. Even when you try to explain it, people can't understand how an aircraft that can operate in thick fog can be forced to divert when the weather is only low cloud. The complexities of aids being out of service wash past them...though I have found that most understand the concept of driving your car in fog at 200 kph being less than ideal.

 

[CaviAck]

No...none. The CSM was expecting to be asked, but nobody wanted to get off. Having too much fun I guess.

If people did ask would you have let them off? It looked like you had a 90min splash and dash. That being said though how many would do LAX-MEL-SYD when there's two LAX-SYD direct flights... I know I did but I wanted the free SCs.

 

[andmiz]

Interesting weights, that I'm not familiar with. What version...747-800F?

Yes, the 747-8F. We operate 6 different model/engine combinations across the passenger/freighter fleet.

 

[flychrisfly]

When landing or at take off is the spacing/separation between two A380s the same as it is for two 737s?

 

[Awesom Andy]

Of course, the day didn't look too bad to those on the ground, so we heard the standard grumbles.

I think most pax forget that they simply don't get to see the bad stuff since you've intentionally avoided it for their safety and comfort.

 

[por930]

...........We watched this all night, and at about 150 miles from Sydney decided that it was not going to miraculously improve, and ducked in for a splash and dash (or as close as we could get to it). Arrived about 90 minutes later, and on the approach on to 34 became visual about 100 feet above the minima. Of course, the day didn't look too bad to those on the ground, so we heard the standard grumbles. If I could have continued safely I would have done so, but it simply was not prudent. This was the 38th time I've done the sector, and the first diversion.

JB, this is exactly the reason why I try and always fly your airline, I can quiet happily snooze when on board knowing the training, company expectations and SOP for your airline always put safety before profit. After you have carried out a diversion, do you have a 'please explain' meeting with your chief pilot, or is a diversion considered within SOP and one of those things?

 

[jb747]

If people did ask would you have let them off? It looked like you had a 90min splash and dash.

The splash and dash part was reasonably quick. I think we were fuelled up and ready to go in about 45 minutes. But, you lose time with taxying, ATC in general, and then the myriad other things that happen at airports all of which cost time. Climbing and descending your average speed is much slower than it is in the cruise.

There was about 300 miles between the point at which we started the descent, and the position at which we got back to FL400. If we'd stayed at FL400 and flown over Sydney, it would have taken about 38 minutes to fly that distance. But, with the much lower average speeds of the climb and descent (the TAS/IAS relationship, plus speed limits), that same distance took over an hour.

 

[jb747]

Yes, the 747-8F. We operate 6 different model/engine combinations across the passenger/freighter fleet.

Very impressive figures. Over 30 tonnes up on the ER at T/O is quite an increase. If operated for range (and that weight were on a pax aircraft), you'd get 1,500 extra miles out of that alone (compared to an ER), ignoring the effects of efficiency increases.

 

[jb747]

After you have carried out a diversion, do you have a 'please explain' meeting with your chief pilot, or is a diversion considered within SOP and one of those things?

A "please explain" after a normal operational decision would be the sort of thing you'd actually report to CASA. That would send a very negative safety message. You might get an email asking about some individual facet of the diversion, or perhaps be asked if you think anything could have been done to help you get away quicker. I don't expect to hear anything.

 

[jb747]

When landing or at take off is the spacing/separation between two A380s the same as it is for two 737s?

There are quite complex rules for separation between aircraft types. You'd need an ATC to explain them all. Basically though, an aircraft of the same or bigger type can follow with less spacing than will be applied if the big type is leading. So, it might be a minute between two 380s (or 737s), but 3 minutes if a 737 is following a 380.

You sometimes see an example of this when watching departures. ATC will let a gaggle of 737/A320s go from an intersection, whilst holding bigger aircraft at the full length. The little guys are jumping the queue, but otherwise ATC will never be able to get everyone away.

 

[mjt57]

JB, thanks for the informative post about your diversion.

A couple of questions.

If I read it correctly, was your flight time SYD-MEL 1 hour? If so, that seems to be fairly quick. I flew to SYD and back recently on a B737. Each trip was about an 80 mins, roughly.

Someone asked about pax wanting to offload at SYD. Would this be allowed given that all the luggage would need to be searched for the few items belonging to the departing passengers?

How long before the runway upgrades are completed? The weather forecast for the next few days isn't that promising. Just wondering if yours won't be the first and only diversion. (Or were there others?)

 

[Flying Fox]

The splash and dash part was reasonably quick...

So fuel is added to your aircraft. Do you add anything else, ie. Catering, bathrooms & aircraft cleaned etc?

 

[serfty]

...
If I read it correctly, was your flight time SYD-MEL 1 hour? If so, that seems to be fairly quick. I flew to SYD and back recently on a B737. Each trip was about an 80 mins, roughly...

As a person who takes note of such things and has PAXed several hundred times between MEL and SYD, I apply a 55 minute 'rule of thumb' for flight time - any less and it's a relatively 'fast' flight and more than that is 'slow'. Note this is air time, taxiing not included. So 1 hour is realistic.

 

[Mattg]

Were you worried about running out of hours and being unable to continue operating the diverted flight to MEL?

If you had've been close to running out of hours, would it have been easy to have a full crew replace you in SYD? And would this play any part in the decision to divert?

 

[jb747]

If I read it correctly, was your flight time SYD-MEL 1 hour? If so, that seems to be fairly quick. I flew to SYD and back recently on a B737. Each trip was about an 80 mins, roughly.

The flight plan was still on my iPad. It was planned at 1:03. The shortest I've ever managed was in a 767, at under 50 minutes. MEL-SYD is normally the faster of the two, because it normally has a tailwind.

Someone asked about pax wanting to offload at SYD. Would this be allowed given that all the luggage would need to be searched for the few items belonging to the departing passengers?

It is allowed in some circumstances. Leave it at that.

How long before the runway upgrades are completed? The weather forecast for the next few days isn't that promising. Just wondering if yours won't be the first and only diversion. (Or were there others?)

The NOTAM was from the 11th, and doesn't seem to have an end date. I'd assume around a month. As far as I know, mine is the only diversion that was a direct result of the works. There will probably be others, but in many cases there will be ways of avoiding it. 27 will be an option for most aircraft, and sometimes for the 380. In general, if we can legally have a look at an approach, we'll be able to land...it's the making it legal bit that you sometimes need to work on. If Avalon is available, it makes it much easier.

 

[jb747]

So fuel is added to your aircraft. Do you add anything else, ie. Catering, bathrooms & aircraft cleaned etc?

Nothing is done that isn't necessary for the flight. So the engineers will have a quick look, and hopefully do nothing other than top up the fuel. Our aircraft had no entries in the log for them to look at. As soon as the fuel docket was signed, we closed the doors.