Ask The Pilot

[andyhui01]

9M-MTI was the plane that operated MH128 the other day. After the overweight landing, it managed to take off about 18 hours later. I know landing gears and brakes have to be checked but in reality, does it actually do much damage to the plane or is it generally OK and the checks are just a precaution?

As for the landing part, I assume ILS can still be used after the pilot reprograms the flight computer? How much harder is it?

 

[JessicaTam]

There has been a large gantry built over Bulla Rd adjacent to MEL. It is on the approach to 27. An upgrade/update to the ILS?

 

[AviatorInsight]

9M-MTI was the plane that operated MH128 the other day. After the overweight landing, it managed to take off about 18 hours later. I know landing gears and brakes have to be checked but in reality, does it actually do much damage to the plane or is it generally OK and the checks are just a precaution?

I do apologise for the late reply, but I'm currently living in Brisbane for about a month while I'm conducting the B737 type rating course (my time has come to actually touch some controls again ).

Overweight landings can be accomplished using normal landing procedures and techniques. Having said that, all overweight landings must be reported in the maintenance log with as much information as possible including sink rate, any drift, blow tyres, etc. This information enables the engineers to perform the correct category of inspection. The lower the sink rate and the smoother the landing (sounds like what we try and do all the time?), will normally save considerable time ensuring maintenance requirements.

As for the landing part, I assume ILS can still be used after the pilot reprograms the flight computer? How much harder is it?

ILS could definitely be used, but for the Boeing, auto land mustn't be used because the autopilots can't cope with the additional weight. It is actually a very simple process with the push of a few buttons to get the ILS identified and usable.

 

[jb747]

9M-MTI was the plane that operated MH128 the other day. After the overweight landing, it managed to take off about 18 hours later. I know landing gears and brakes have to be checked but in reality, does it actually do much damage to the plane or is it generally OK and the checks are just a precaution?

When the aircraft are designed, maximum landing weight is certified at a given rate of descent. I'm not sure what the number that is used is, but I think it's in the order of 10 feet per second. Now that's a pretty horrific 600 fpm (which is basically the sink rate on an ILS), and so would be VERY HARD. Pretty much a landing without any flare at all. G wise, it's about 1.8 g. A normal landing, is only a couple of feet per second. BTW, even though you're all critics of landings, even those of you who think you've experienced a heavy landing, almost certainly haven't.

If you need to land at a weight greater than the max landing weight, then you'll need to ensure that the sink rate is nowhere near that certified number, i.e. the flare MUST work. The best way to ensure that is to make an automatic landing. You could do it yourself, but it if you get it wrong, and autoland was available, you'll have some explaining to do. There are many scenarios in which autoland will not be available...so you just have to get it right!

As for the landing part, I assume ILS can still be used after the pilot reprograms the flight computer? How much harder is it?

When we arrive at an airport we'll have the most likely STAR and approach loaded into the FMC. We don't know for sure what it will be until we talk to approach. Generally we have the correct one loaded, but changes happen often, ranging from simple things like cutting some waypoints out of the arrival, to completely different runways (and directions). On my last arrival into Melbourne (from LA) we were well into the STAR for 34, when we were advised of a wind change which made 16 the preferred arrival. It probably took less than 60 seconds to change the STAR, and load the new approach and its details. Sometimes we'll have alternatives loaded in the secondary route pages of the FMC, but I find it's just as easy to use the active pages.

As long as you have the correct ILS frequency and track loaded in the RAD/NAV page, it actually doesn't matter if the tracks (STAR/approach) are correct. We always keep the map tidy though, and that means that we update it right up to finals.

If (for instance) you were given a late sidestep to another runway (perhaps LA 24R to 24L), you'd turn the flight director/autopilot off, and line the aircraft up visually. The non flying pilot may have time to change the runway, but you probably wouldn't bother. At the end of the day, they're still just aircraft.

 

[AviatorInsight]

When the aircraft are designed, maximum landing weight is certified at a given rate of descent....

If you need to land at a weight greater than the max landing weight, then you'll need to ensure that the sink rate is nowhere near that certified number, i.e. the flare MUST work. The best way to ensure that is to make an automatic landing.

That's interesting in the difference between aircraft makers. According to Boeing, overweight autolands are not recommended, even on the B777. The autopilots are actually not certified for autolands above max landing weight.

 

[andmiz]

That's interesting in the difference between aircraft makers. According to Boeing, overweight autolands are not recommended, even on the B777. The autopilots are actually not certified for autolands above max landing weight.

Depending on aircraft type, both manufacturers are quite similar. It's the differences between certified, recommended, demonstrated and 'consider in an emergency'.

 

[Skyring]

When the aircraft are designed, maximum landing weight is certified at a given rate of descent. I'm not sure what the number that is used is, but I think it's in the order of 10 feet per second. Now that's a pretty horrific 600 fpm (which is basically the sink rate on an ILS), and so would be VERY HARD. Pretty much a landing without any flare at all. G wise, it's about 1.8 g. A normal landing, is only a couple of feet per second. BTW, even though you're all critics of landings, even those of you who think you've experienced a heavy landing, almost certainly haven't.

You'd have some experience there, I guess.

Landing a Skyhawk on a carrier must be pretty firm.

 

[jb747]

There has been a large gantry built over Bulla Rd adjacent to MEL. It is on the approach to 27. An upgrade/update to the ILS?

I don't know for sure Jessica. There has been a lot of work lately on the lighting, and there is currently a NOTAM about replacement of the HIALs for 27, which would probably fit in with the work you've seen.

 

[jb747]

Landing a Skyhawk on a carrier must be pretty firm.

Everything about that sort of aircraft is pretty firm!

Even when landing ashore, there was no flare at all. The undercarriage had a lot of compression, and just about no rebound, so it just impacted, and stayed down. The g meter would often show +8/-3g after a normal landing...which I guess just means the meter couldn't really hack it.

For fatigue reasons, other operators did use a flare, but because the approach was so far off the back end of the drag curve, it was done mostly with power, and not attitude change.

 

[jb747]

Depending on aircraft type, both manufacturers are quite similar. It's the differences between certified, recommended, demonstrated and 'consider in an emergency'.

A380 is 'demonstrated to maximum take off weight'.

 

[Awesom Andy]

A380 is 'demonstrated to maximum take off weight'.

What does "demonstrated" really mean? Something along the line of "we managed to do it once but if it stuffs up when you do it, you can't blame us?"

 

[jb747]

What does "demonstrated" really mean? Something along the line of "we managed to do it once but if it stuffs up when you do it, you can't blame us?"

Probably more a case of we tried it once, and when it worked, decided to stop whilst ahead.

 

[Quickstatus]

http://avherald.com/h?article=4a9ced39&opt=0

No maps of destination so had to turn around.
Would appreciate a overview of map data storage on a flight deck. Used to be Jeppesen charts then electronic iPads. However can't these be integrated into the flight computers?. Terabyte SSD exist which are energy efficient and reliable.

 

[Skyring]

Even when landing ashore, there was no flare at all. The undercarriage had a lot of compression, and just about no rebound, so it just impacted, and stayed down. The g meter would often show +8/-3g after a normal landing...which I guess just means the meter couldn't really hack it.

Consider my jaw dropped. And my spine tingled, a little.

Drop an A380 on the deck at anything like that and maybe the airframe would remain in one piece, but there must be limits on things like overhead bins, various fastenings, seats and seatbelts. And people.

Overweight landings aside, what sort of practical limits are there for airliners and their passengers in normal operation?

 

[JessicaTam]

I don't know for sure Jessica. There has been a lot of work lately on the lighting, and there is currently a NOTAM about replacement of the HIALs for 27, which would probably fit in with the work you've seen.

Thanks. I will try to get a pic next time I pass by.

 

[jb747]

Drop an A380 on the deck at anything like that and maybe the airframe would remain in one piece, but there must be limits on things like overhead bins, various fastenings, seats and seatbelts. And people.

The reality, of course, is that the g meter couldn't handle landings, and displayed numbers that were gibberish. The real g would have been, perhaps, 2. The nose gear had quite substantial rebound, and would bounce the nose back up, and I always suspected the readings were influenced by that. The intention of the rebound on the n/g was to make achieving a go round attitude pretty much automatic.

Overweight landings aside, what sort of practical limits are there for airliners and their passengers in normal operation?

I don't recall hearing figures for the Airbus, but the Boeings were 1.4g for an inspection, and at 1.8g it was an outright heavy landing. Most landings are under 1.1g, and when the cabin crew and passengers start complaining it's about 1.111g.

 

[jb747]

Incident: Cathay Dragon A320 near Hong Kong on Jun 1st 2017, unmapped flight

No maps of destination so had to turn around.

In the days of paper charts, something like this used to happen every now and then around the world. I recall a QF flight being caught out, when the chart load was incomplete. The SO looked, and found the leading charts, but the actual approach plates were missing. I expect this sort of thing happened more than has been admitted, because the crews had a way of working around it. Whether they should have or not, is a different question.

Would appreciate a overview of map data storage on a flight deck. Used to be Jeppesen charts then electronic iPads.

I don't know what other airlines do. We only have the Jepps on the iPads now. The CSM iPads also load the charts, so if one of our iPads plays up, we'll take theirs. Spares are held at every port.

Originally, the Jepp data was available on the OIT (the laptop which uses two fixed screens in the coughpit). This system was hated by just about everyone, as it was an electronic system purely for it's own sake. It was slower, less flexible, and harder to use, than a paper chart. As we still carried the charts, virtually everyone used them. Ultimately, the iPads supplanted both the OIT and the paper. Prior to the flight, we download the flight plan from the Jepp app, and separately via a company app. When the route is loaded into the Jeppesen, it adds the destination, and any other points that we select, to a side window from which all of the charts are available. An error is shown if it doesn't know the airport.

The FMCs do contain a lot of data relating to approaches/arrivals/departures, but they don't have items like the minima, frequencies, or terrain. We could get away with using FMC data in an emergency, but not any other time. Neither system contains the entire world, only a subset as requested by each airline.

However can't these be integrated into the flight computers?. Terabyte SSD exist which are energy efficient and reliable.

No access to these systems is allowed. Something could be loaded to the laptop, but that is isolated from the aircraft. iPads are really an almost ideal solution. They are cheap, easily replaced and stored. Updates happen over wifi or 4g (I've just updated the Jepps whilst writing this). They even allow for coughpy old eyes.

I don't know exactly what happened in the incident you've mentioned, but I suspect that the destination wasn't a normal one for the aircraft, and that the charts were therefore not in the iPad load. In which case they wouldn't have been in a paper load either.

 

[Quickstatus]

Thanks JB747, what would be the ideal map handling solution on aircraft such as the ones you fly if ipads are the almost ideal?

What are the pros and cons of the FMC holding all the necessary map data?

.....


Eyes:

An urban myth? used to exist that to become an airline pilot one at least had to have very good eyesight. But reading other blogs and forums robust cognitive processes and psychological profile seems to be more important. Any insights?

 

[Melburnian1]

I asked this in the JQ delays and cancellations thread but many of our AFF members appear not to fly with that QF subsidiary and hence are unlikely to read that thread.

This morning LST looked to be fogbound. JQ731 almost made it, but turned back and diverted to MEL. By 1015 hours, LST reopened.

HBA had its 'mid morning peak' at the time, but was open. Is there any reason why JQ731 could not have diverted to HBA, delivering passengers and freight to an airport two hours or so by road to LST? Of course, departing passengers and freight (from LST) might have been stranded. At 1045 hours, JQ731 has yet to leave MEL for the second time on Monday 5 June, so it is now hours late.

 

[AviatorInsight]

Eyes:

An urban myth? used to exist that to become an airline pilot one at least had to have very good eyesight. But reading other blogs and forums robust cognitive processes and psychological profile seems to be more important. Any insights?

Cognitive processes and psychological profiles are the responsibility of the employer. Obtaining a medical is done externally from the company to a Designated Aviation Medical Examiner. The have good eyesight, yes that is a prerequisite, but if it's able to be corrected to 20/20 by glasses/contacts/laser eye surgery, then that's all that's required.

Colour blindness is more limiting. Those people who can't see red or white may have a harder time obtaining a class one medical to fly commercially, on a case by case basis.