Ask The Pilot

[welltravelled]

Since we are talking about landing speeds, just what are they ? Do the larger aircraft land at a higher speed than say a 737 ?

Not necessarily, take off and landing speed is calculated as a function of stall speed, which is the speed at which the wing no longer flies, or develops lift.
There is a buffer applied to this, the 737 typically used 1.3, or 130% higher than the stall speed.
The A330 approaches about 10-15 knots slower than the 737 because the wing is so much bigger and more efficient.
Typical approach speed for A330-200 at moderate weight is 125-130 Knots, whereas the 737-800 is 140-145 knots.
The -800 has the same wing as the-600 and -700 but the longer fuselage means increase overall weight, higher stall speed, hence higher take off and approach speeds.

 

[jb747]

As with everything in aviation, there's never one simple answer. As explained above, the minimum approach speed is a mandated number, based upon the stall speed. As the stall speed varies with configuration and weight, that number will be higher with less flap or more flap.

But, another part of the equation is that the approach speed chosen should be 'speed stable'. The total drag graph for an aircraft is an inverted bell shape. All other things being equal (hah!), the approach speed should be just above the min drag speed. The reason is that if the aircraft is disturbed (and no approach is ever totally stable), any increase, or DECREASE, in speed will result in the drag changing in such a way that the aircraft will tend to go back to its original speed without pilot intervention. Faster, more drag, so it slows again...but slower, less drag, so it accelerates.

If you were to choose a slightly slower speed, right on min drag, the speed would only be stable in one direction. Faster, more drag, and it would slow. But, slower, also more drag, and the deceleration would continue.

Conversely, if you choose a speed lower than min drag, the speed becomes unstable in both directions. Some military aircraft are operated in this area...generally carrier based aircraft, where the most important factor becomes the final energy at touchdown, and ease of flying, or safety, are secondary.

So, are the bigger aircraft approach speeds higher than the smaller aircraft? In some cases, but it has much more to do with wing loading, and wing design. Wing shapes that work well in the cruise or high speed parts of flight, mostly aren't nicely behaved when slower. A reasonable way to guess relative approach speeds is to look at wing area vs weight. This is called wing loading, and is measured in pounds per square foot. The lower the number the better. Again, with the rule that there is no free lunch in aviation, a nice low wing loading, that gives low approach speeds and low stall speeds, will also be more affected by any gusts...i.e. it won't be as nice a wing in turbulence.

 

[clazman]

Just waiting to board a AC flight to Toronto and watched the pilot and first officer approach the gate check in and wait. The gate checkin staff then asked them to approach the desk had a quick conversation and then allowed them to board.

I would assume there is a security protocol to get onboard?

If you can comment while maintaining security it would be appreciated

 

[Boris spatsky]

I assume that they were on duty or staff travel but on a standby ticket as passengers. They would have been last on if seats were available.

 

[RooFlyer]

I assume that they were on duty or staff travel but on a standby ticket as passengers. They would have been last on if seats were available.

I'm conscious of the nature of this thread, but as a frequent AC traveller, it is very common with Air Canada to observe multiple uniformed crew (usually appear to me to be coughpit crew, together with their Gladstone type bags) to be called to board first and be seated in J (perhaps with others in Y). I have assumed they are 'positioning' and more power to them in J. Although I got my nose out of joint once when in an E190, with 'crew' occupying 2/3 of the 9 seats in J and one side with overhead bins suitable for handbags only, there was no space left for my carry-on .

 

[Boris spatsky]

Yes, if in uniform then probably duty travel. Dependant on the company, this can be in J.

 

[por930]

Yes, if in uniform then probably duty travel. Dependant on the company, this can be in J.

I have been reading a blog written by a US pilot. Many of his blogs refer to his commitment to commuting between destinations and back to home after each set of flights. Apparently, all airlines in the states allow other airline flight crews to commute at no cost in each others aircraft. He said travel can be out of uniform, but as most of the crews are just finishing a final leg and going home, they study the various time tables the night before travel home, to work out the best chance of a seat(as compared with an coughpit jump seat)

The blog goes into the daily life of a domestic pilot working his way through the seniority ranks. A lot of information is provided about his qualifying school on the simulators for the A320. Overall, a great read, and will answer many questions about, what do those guys do up there.....

The Renewed Pilot Blog | Table of Contents

 

[clazman]

I assume that they were on duty or staff travel but on a standby ticket as passengers. They would have been last on if seats were available.

These were our pilot and first officer... About 6 AC staff came to the gate closer to load time and sat in Y

 

[Boris spatsky]

Pilots can usually access the gates when ground staff are not present so that they can commence pre-flight duties. I suggest that the ground staff were discussing an issue with the load with them prior to departure.

 

[mjt57]

Apparently, all airlines in the states allow other airline flight crews to commute at no cost in each others aircraft.

When my wife worked at Pan Am (La Guardia), she was able to fly either with PA or other airlines via what she called ID90 discount. Only requirement was to dress for 1st class. She had the opportunity to fly in the Concorde to Paris and to take the kids with her, but circumstances prevented it. But it was a no brainer to jump on one of the Boston shuttles and head there for the day with the kids.

She managed to fly here for under $100.

 

[mjt57]

Article in the paper today about on board wifi being able to "hijack" the aircraft's avionics.

Hackers could hijack aeroplanes through passenger Wi-Fi, report warns

I thought that the inflight entertainment service was totally separate to any of the critical systems within the aircraft.

Is this not the case?

Or is some public servant trying to make a name for himself within his own department?

 

[jb747]

Article in the paper today about on board wifi being able to "hijack" the aircraft's avionics.

Hackers could hijack aeroplanes through passenger Wi-Fi, report warns

I thought that the inflight entertainment service was totally separate to any of the critical systems within the aircraft.

Is this not the case?

Or is some public servant trying to make a name for himself within his own department?

Quite a load of rubbish. They basically say so themselves...i.e. 'if the Wi-Fi system shares the same wiring harness or router as the plane's avionics system'...which it doesn't. End of story.

 

[clazman]

Any comments about the turbulence in and around LAX / LAS, never experienced anything like it...

Is this normal? I am assuming it is caused by the air bouncing around the hills / mountains

 

[ChrisGibbs]

JB747 - was on the Qantas Codeshare Emirates 777 service from SIN-BNE last night. We made our approach to RWY 01 at BNE with the mains touching down for what I thought was a nice landing. The engines then spooled up and we then proceeded to do a go around. Once the aircraft was cleaned up the captain came on the PA and said the maximum down wind component had been exceeded in the final stages of the approach and the go around was executed. We eventually came back and made an approach and landing on RWY 19. A couple of questions for you:

- is the maximum downwind component a limitation of the aircraft, runway being used or a combination of things?
- given that time of the morning with minimal traffic and a minimal downwind on RWY 01 would approach give the PIC the option for either RWY 01 or 19? I would imagine an approach to RWY 01 could cut up to 5-10 minutes off of the approach compared to RWY 19.
- in something like a 777 what would that maximum downwind component be?
- over the years I've done a bunch of go-arounds which are typically executed at the approach minima. How often are go-arounds executed after the aircraft touches down. Is this as a result of a lag between the decision being made to go around and the engines spooling up. How late in the landing roll can / should the decision be made to go-around?
- During the non daylight savings period in YSSY a couple of Qantas and BA arrivals can be made onto RWY34L from 5:00am prior to the curfew being lifted at 06:00am. I would presume any downwind component would have to be taken into account prior to an approach being made for RWY34L being made as the noise created from a go around off RWY34L at 5:00am over the inner west of Sydney would create a lot of paperwork.

Thanks in advance.

 

[clazman]

Adding a bit more detail, came into lax on AC about lunch time over flying LAS (according to in flight map) and from las to lax was bumpy, 5 hours later going lax to las with AA still bumpy

 

[jb747]

Adding a bit more detail, came into lax on AC about lunch time over flying LAS (according to in flight map) and from las to lax was bumpy, 5 hours later going lax to las with AA still bumpy

I operated through LAX just the other day (and will again in couple of days)....and it was smooth. There is normally a fair bit of clear air turbulence between LA and HNL, and that was there. To the east, towards LAS, you could get some induced by the mountains, but I haven't experienced anything out of the ordinary on those times that I've flown in that direction.

 

[Dmac6345]

I operated through LAX just the other day (and will again in couple of days)....and it was smooth. There is normally a fair bit of clear air turbulence between LA and HNL, and that was there. To the east, towards LAS, you could get some induced by the mountains, but I haven't experienced anything out of the ordinary on those times that I've flown in that direction.

Flew on 94 the other day and between LA and HNL was terrible. Pilot came over and said not much could be done with the bumps due to clear air turbulence. It wasn't super bad, but just annoying enough to be slightly uncomfortable (even in F).
I don't know what happened after that. I woke up with 3 hours remaining

 

[Flying Fox]

I just read that EK have ordered a bunch of new A380s with RR engines vs their current engines.

As a pilot, are there any differences between flying the different engine types on the same aircraft type?

 

[jb747]

- is the maximum downwind component a limitation of the aircraft, runway being used or a combination of things?
- in something like a 777 what would that maximum downwind component be?

There is an absolute limit, which I expect is 15 knots. That could be reduced in some configurations. You would be performance limited on a shorter runway...we work that figure out if we need to.

- given that time of the morning with minimal traffic and a minimal downwind on RWY 01 would approach give the PIC the option for either RWY 01 or 19? I would imagine an approach to RWY 01 could cut up to 5-10 minutes off of the approach compared to RWY 19.

If you want a particular runway, you need to say that you require it.

- over the years I've done a bunch of go-arounds which are typically executed at the approach minima. How often are go-arounds executed after the aircraft touches down. Is this as a result of a lag between the decision being made to go around and the engines spooling up. How late in the landing roll can / should the decision be made to go-around?

A go around can happen at any time. They are only noticeable if you're well into the approach, as a very early one may just seem like some added manoeuvering. They can be initiated any time prior to selecting reverse thrust. A really late one may involve a touchdown.

I've done a couple down at at 20-50 foot level. You don't always wait to get to minima before going around...last one I did was at about 500 feet.

- During the non daylight savings period in YSSY a couple of Qantas and BA arrivals can be made onto RWY34L from 5:00am prior to the curfew being lifted at 06:00am. I would presume any downwind component would have to be taken into account prior to an approach being made for RWY34L being made as the noise created from a go around off RWY34L at 5:00am over the inner west of Sydney would create a lot of paperwork.

If the downwind is outside of limits, then you have to hold until the normal opening time. If a go around occurs, then that's just bad luck. No particular paperwork...rather more if you didn't.

 

[jb747]

I just read that EK have ordered a bunch of new A380s with RR engines vs their current engines.

As a pilot, are there any differences between flying the different engine types on the same aircraft type?

In general there's not much difference, especially when they are electronically controlled...which tends to mask differences anyway.

The 767-300s with the RR vs the GE...most of us liked the GE better. There was a difference in their idle behaviour that made the aircraft quite different in the flare, and gave us two different landing techniques. Everyone hated the PW, so best not mentioned.