Ask The Pilot

[Captain Halliday]

Thoughts gentlemen?

 

[AviatorInsight]

Thoughts gentlemen?

That should have been a go around. It’s called a touchdown zone for a reason and they missed it completely.

Looked like they were trying to go for the “greaser” but pulled back a little too much and ended up “ballooning”.

The key here is when ATC issued the wind on final and mentioned the tailwind, it has a tendency to do exactly what happened to the A380.

 

[jb747]

Whilst many airlines prescribe a distance beyond which a go around must be performed, not all do. Emirates did, and look how that worked out for them. Others allow a last point of touchdown to be defined for each landing, which, off my head for 16 Sydney would be about the intersection. The aircraft also has ‘brake to vacate’, and dynamic overrun protection, so unless that started yapping at you, you’d know that there’s sufficient runway remaining.

My guess is that he’s very light, and that the tailwind goes away and even becomes a slight headwind at the flare. He also ends up right of centreline, so quartering wind from the left. And, if the video was shot recently, he may well not have flown all that much lately. A weakness of the A380 is a lack of control feel in the flare. The issue may exist across all of the FBW airliners, but I think size accentuated it in the 380. For that reason I never tried to get greasers. If I did it was accidental. I just killed the sink rate, and then let it go on. Greasers may be how passengers judge landings, but this is a good example of why pilots don’t.

 

[mjt57]

Greasers may be how passengers judge landings, but this is a good example of why pilots don’t.

The pilot flying our JQ B787 into HON must have gone to the JB School of Landings. He thumped it hard onto the runway, so much so that my torso's overall length was shortened by 4.8mm.

But it was bucketting down at the time.

 

[jb747]

The pilot flying our JQ B787 into HON must have gone to the JB School of Landings. He thumped it hard onto the runway, so much so that my torso's overall length was shortened by 4.8mm.

But it was bucketting down at the time.

He did it right then. Your back will grow back...

Air Force pilot landing, vs, navy pilot landing.

 

[AviatorInsight]

But it was bucketting down at the time.

All the more reason to thump it on. Hydroplaning is a real problem when the runway is wet. While many pilots think it's great getting a greaser on a wet runway (and easy to do with a thin film of water on the surface), it will actually make the braking action worse.

 

[Carrots]

@AviatorInsight you're not on VA223 today are you? Have important freight onboard!

Edit - oops scrap that, not likely given your post on here twenty mins ago!

 

[mjt57]

All the more reason to thump it on. Hydroplaning is a real problem when the runway is wet.

Yep, so I understand. I've never seen so much rain before. Wonder if they should've fitted floats to the wings.

As for braking, aircraft have ABS? If so, how effective is it in the wet?

 

[AviatorInsight]

@AviatorInsight you're not on VA223 today are you? Have important freight onboard!

Edit - oops scrap that, not likely given your post on here twenty mins ago!

Unfortunately not, I've just been advised my daughter is a close contact and now have to remain in isolation for 7 days. I was scheduled to fly over the next 4 days anyway.

On the bright side I get to spend Christmas with my kids.

 

[AviatorInsight]

Yep, so I understand. I've never seen so much rain before. Wonder if they should've fitted floats to the wings.

As for braking, aircraft have ABS? If so, how effective is it in the wet?

Yes they do and it's very effective. The anti skid system offers locked wheel protection, hydroplane protection, and gear retract braking inhibit.

In terms of wet runways, the hydroplane protection system compares wheel speed data to the air data unit that gets the ground speed info. When the wheel speed decreases to 50 knots less than the ground speed, the protection system kicks in and releases pressure to wheels 1 and 3 only.

 

[Carrots]

Unfortunately not, I've just been advised my daughter is a close contact and now have to remain in isolation for 7 days. I was scheduled to fly over the next 4 days anyway.

On the bright side I get to spend Christmas with my kids.

Thankfully whoever was in charge did a good job of getting the new little man over here safe and sound. Everyone needs a puppy for Christmas right?!


A good upside, hopefully all safe and sound over the coming week!

 

[jb747]

As for braking, aircraft have ABS? If so, how effective is it in the wet?

Whilst anti skid had been experimented with for quite some time, it first appeared in aircraft in the 50s. It makes huge difference to braking performance. If the system fails, you'll have to apply a enormous penalty to calculate your runway requirements. Something in the order of an extra 50 to 100% on a wet runway. And, as there is no feel through the brakes, if you don't have anti skid, and lock up a wheel or two, you won't know before you destroy the tyre(s).

On the bright side I get to spend Christmas with my kids.

Take that as a winner. Over my entire career, I had very few Christmases at home.

 

[albatross710]

To be honest, a proper treatise on fuel planning and management would be even more confusing than the GLS/RNP discussion.

The upshot though, is that there is a difference between a legal amount of fuel, and a sensible one. Arriving at place like Dubai, with divert fuel to an airport 25 miles away may well fulfill all legal requirements. But, common (?) sense says that there's likely to be extensive holding there even in good weather, so even though additional holding might not be legally required, it's very likely to be needed. So, arriving with divert fuel and being unable to hold will simply result in you having to divert immediately. Legal. Safe. Dumb.

This accident investigation I was watching online has an example of a pilot that was unfortunately choosing to divert to multiple airports all with the same weather problem. Departed with 5 hours fuel for a 3 hour flight.

 

[Saab34]

There was a fuel incident down this way wasn’t there? Mildura and something around VA and QF 737s.

 

[AviatorInsight]

This accident investigation I was watching online has an example of a pilot that was unfortunately choosing to divert to multiple airports all with the same weather problem. Departed with 5 hours fuel for a 3 hour flight.

A very good video in my opinion. It’s where experience plays a big part. I don’t know how many times the forecast has been so wrong, but luckily I have always carried extra fuel due to experience with weather patterns in the area and looking at more resources than just the forecasts themselves.

Here is an example from a few days ago. We had MEL - CNS. CNS weather indicated light showers with visibility still 10km and cloud broken at 4000ft.

The Capt suggested that weather in CNS looked good with just passing showers. Now I have had extensive time flying in North Queensland to know that light showers in the wet season doesn’t always mean light.

Given it was my sector anyway I elected to add an extra 30 mins on arrival into CNS plus my standard alternate for TSV (weather there looked much better).

About an hour from top of descent the weather turned on CNS and we suddenly needed an extra 30mins fuel (lucky we had that) where the were periods of heavy rain and visibility dropping to 4000m with low cloud at about 700ft.

What were our options? We had fuel to hold for 30mins and then divert to TSV. We had already been given our approach clearance for the GPS based approach. At the decision height we needed 3km visibility so we should have the visibility required and the minimum cloud base required was 100ft below the reported cloud from ATC. The ILS was NOTAM’d unserviceable for our arrival. There was also a quartering tailwind to runway 15. So I looked at runway 33. Because of the high terrain around, all of the minimums were much higher and we wouldn’t get visual. So we committed to 15.

Once we started the approach, visibility worsened with a shower right on the approach path around the minima. About 100ft above decision height the captain could spot the approach lighting and we could continue having the runway positive identified throughout from that point. We exited the rain about 300ft above ground level and continued to a safe landing.

If we didn’t carry TSV as a personal alternate and any extra fuel we would have needed a splash and dash in TSV before continuing on. By then we possibly may have run out of hours as we had flown down to MEL from CBR just prior. All for 1 tonne of fuel extra.

 

[Saab34]

At what stage in your career do you learn all about fuel and alternates etc? Is that ATPL or is that learnt during airline line training? Do rules differ across employers, or does CASA have the same sort or approach for all?

 

[jb747]

There was a fuel incident down this way wasn’t there? Mildura and something around VA and QF 737s.

Investigation: AO-2013-100 - Landing below minima due to fog involving Boeing 737s, VH-YIR and VH-VYK, Mildura Airport, Victoria on 18 June 2013

This was a particularly interesting event, as both aircraft obeyed the rules, but still ended up in a very nasty situation. Arguably, it would have been much safer to totally ignore the rules, and stay at Adelaide, which at least had an ILS and so offered the chance of autoland. Of course, the CASA response would have been to hang the crew....

This was another example of the extremely poor aviation infrastructure within Oz.

 

[jb747]

At what stage in your career do you learn all about fuel and alternates etc? Is that ATPL or is that learnt during airline line training? Do rules differ across employers, or does CASA have the same sort or approach for all?

You start learning about fuel on your first flight, and you stop after your last one. You might learn the rules at various examination points along the way, but you're always learning new tricks and traps.

 

[jb747]

A visitor in tonight's sky.

 

[mjt57]

Nice shot. Gear details and settings?