The great big "ask an airline pilot" thread!

Aphex

Hopefully. It would be nice to have him on here.

Question: How sturdy is a plane? How can something that is attached together in many sections be so "solid"?

lambayire

This is probably a really stupid question.

I live in Baldoyle. I guess the planes pass by about a mile or so from the house.

Yesterday the planes were leaving from runway 10. It seemed to me that the planes were quieter at night than during the day as the flew over us.

Does this make any sense?

faceman

Do airlines have differing policies on turbulence and turning on the seat belt sign?

I find that BA dont often turn on the light unless its gets really bumpy but I find EI will flick the light on sooner. Is it in my head?

bkehoe

faceman wrote: »

Do airlines have differing policies on turbulence and turning on the seat belt sign?

I find that BA dont often turn on the light unless its gets really bumpy but I find EI will flick the light on sooner. Is it in my head?

Usually the individual crews discretion.

Dr.Rieux

With all the sandy rain in Dublin last night what extra prep work would be needed before first flights this morning? I am assuming some cleaning of the wing surfaces would need to take place, and if so, how would it be done?

Jack1985

lambayire wrote: »

This is probably a really stupid question.

I live in Baldoyle. I guess the planes pass by about a mile or so from the house.

Yesterday the planes were leaving from runway 10. It seemed to me that the planes were quieter at night than during the day as the flew over us.

Does this make any sense?

Absolutely. Most probably as a result of ATC putting what's termed NADP1 into use at night, whereas NADP2 would be used during daylight hours. In brief;

NADP1 - Noise Abatement Departure Procedure One:

Aircraft climbs away from the runway at it's V2 speed + between 10 to 20kts, at 800ft AGL* aircraft goes to Climb Thrust but maintains V2 speed + between 10 to 20kts until reaching 3000ft AGL (Above Ground Level) where the aircraft will accelerate to flaps up speed and then retract the flaps/slats.

Result: Faster initial climb and less noise to surrounding areas.

NADP2 - Noise Abatement Departure Procedure Two:

Aircraft again, climbs away from the runway at it's V2 speed + between 10 to 20kts, at 800ft AGL* aircraft goes to Climb Thrust then accelerates to flaps up speed and retracts flaps/slats, thereafter it maintains the flaps up speed plus between 10 to 20kts. Upon reaching 3000ft AGL, the aircraft accelerates to climb speed.

Result: Slower initial climb and more noise to surrounding areas; when compared to NADP1.

*800ft AGL is the minimum altitude - It can be higher than that.

These are the two defined procedures, but in the majority of cases especially at quieter airports, flights can disregard both NADP procedures when advised by ATC as they can as well at larger airports.

Hope that answers your question!

billie1b

lambayire wrote: »

This is probably a really stupid question.

I live in Baldoyle. I guess the planes pass by about a mile or so from the house.

Yesterday the planes were leaving from runway 10. It seemed to me that the planes were quieter at night than during the day as the flew over us.

Does this make any sense?

Was it a clear sky last? Planes will be a lot louder on cloudy days as you have the sound coming from the plane and the same sound reflecting back down due to the clouds. If its clear skies it will come across as a lot quieter

lambayire

Wow. Thanks for that answer.

As regards the weather for the past few days, it has been both clear and cloudy.

Runway 10 has been in use for about a week now and it has been noticeably quieter at night time all that time.
I like when 10 is in use because it's "normally" a good indicator that the weather is pretty good.
Although I don't like landing on anything other than 28 because it's very comforting flying in over Howth and then over near the house.

faceman

lambayire wrote: »

Wow. Thanks for that answer.

As regards the weather for the past few days, it has been both clear and cloudy.

Runway 10 has been in use for about a week now and it has been noticeably quieter at night time all that time.
I like when 10 is in use because it's "normally" a good indicator that the weather is pretty good.
Although I don't like landing on anything other than 28 because it's very comforting flying in over Howth and then over near the house.

10 is great when you're flying home from US. Not so great when flying from Europe.

Back on topic, a funny thought occurred to me today during a longer than normal taxi at Heathrow. Does a pilot need to have a driver's license? If not, have you ever come across a pilot who didn't have a drivers license?

bkehoe

Jack1985 wrote: »

Absolutely. Most probably as a result of ATC putting what's termed NADP1 into use at night, whereas NADP2 would be used during daylight hours. In brief;

I've never been to any airport where ATC defines what NADP procedure to use depending on time of day.

In some airports different runways have different NADP profiles depending on the areas under the flight paths. This would be notified in Jepp briefs or a company notam/brief. Also in some noise sensitive airports, like Madrid, there are different routings for departures late at night as opposed to during the day.

However, there are no alternate routings in Dublin and the NADP is the same on all runways.

As for drivers licences, no pilots do not need a driving licence and I have come across CPL holders with no driving licence.

Jack1985

I've never been to any airport where ATC defines what NADP procedure to use depending on time of day.

Usually set out in the ADI/General Info as to what the airport defines as its NADP - NADP1/NADP2 are ICAO Standard NADs;

Example from EPWR, ADI - ''ICAO Standard NADP1 applies.''

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Isnt Dub NADP 1.5 regardless of runway or time of day?!

Jack1985

All runways follow this procedure (when advised) for CAT C/D aircraft (Slight variation when departing from R10);

To 1,500ft AGL
Take-off power
Take-off flaps
Climb at V2 + 10-20kt

1,500ft to 3,000ft AGL
Reduce power to not less than climb thrust.
Accelerate smoothly to 230kt with flap retraction on schedule.

At 3,000ft AGL
Transition smoothly to en-route climb speed. Commence turn not below 3,000ft AGL. Disregard when departing from R10 (5nm before beginning turn departing R10).

Above applies to CAT C/D aircraft, CAT A/B can turn at 750ft AGL regardless. Basically the DUB, NADP profile mirrors NADP2 with slight variations to suit the airport.

smurfjed

First time that i have seen the use of the term "Environmental Corridor", this is taken from the Dublin Jeppesen chart..

CAT C & D aircraft using RWY 10 shall operate within an environmental corridor which is based on the RWY takeoff flight path area. The corridor has a width of 180m at the end of the clearway, diverging at 12.5% on each side to a max width of 1800m, and extending from the point of origin to 5NM for the northern boundary of the corridor to 6nm for the southern boundary of the corridor. There is no upper limit to this corridor.

Is this unique to Dublin?

Tenger

bkehoe wrote: »

As for drivers licences, no pilots do not need a driving licence and I have come across CPL holders with no driving licence.

Same here

bkehoe

Jack1985 wrote: »

Usually set out in the ADI/General Info as to what the airport defines as its NADP - NADP1/NADP2 are ICAO Standard NADs;

Example from EPWR, ADI - ''ICAO Standard NADP1 applies.''

So you're confirming that ATC do not define or alter NADP profiles to be used then.

For clarification to anyone looking if there is confusion; NADP profiles simply define where an aircraft begins to accelerate and retract flaps. Noise preferential routings are not related to the NADP profile.

Jack1985

So you're confirming that ATC do not define or alter NADP profiles to be used then

Affirm! Was just showing the ICAO standard ones to show the differences, but NADPs are as you said earlier majorily down to the airport's own requirements.

You don't fly the 320 by any chance? Have a few questions regarding the MCDU

coylemj

Question for commercial pilots.....

Do all passenger airlines land manually i.e. is the autopliot always disengaged a matter of seconds before touchdown? I have heard that an automated landing is usually hard so the pilots prefer to manually land the plane.

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Yes most airliners are landed manually. It can be manually flown to touchdown from as much as 20,000ft although the majority of pilots usually disconnect the automatics at between 3,000ft to 300ft.
Automatic landings are generally only flown when it is very foggy. In a year I may only carry out 4 autolands. And yes the computer can be a little harsh with the touchdown.

smurfjed

We operate about 150 aircraft, none of them are (local CAA) approved for auto land by the autopilot. So all landings are done by the crew.

conor_ie

I've always wondered as planes are being pushed by the ground crew, Sometimes I spot the dispatcher chatting to the flight deck, I was wondering what is that conversation?

billie1b

conor_ie wrote: »

I've always wondered as planes are being pushed by the ground crew, Sometimes I spot the dispatcher chatting to the flight deck, I was wondering what is that conversation?

The conversation goes :

Captain : Ground to flight deck

Ground : Flight deck go ahead

Captain : please confirm all checks complete and bypass pin installed?

Ground : All checks complete and bypass pin is installed

Captain : Ok, we are clear to push and start, call when ready for brakes.

Ground : Clear to push, release brakes please

Captain : Brakes released.

Ground : Brakes released, commencing push.

Captain : Let us know when we are cleared to start No 2?

Ground : Clear 2

Captain : Starting 2, Clear on No 1?

Ground : Clear 1

Captain : Starting 1

Ground : Pushback complete set brakes please

Captain : Brakes are set, clear to disconnect the tow bar, tug and pin, call when disconnected

Ground : Tow bar, Tug and bypass pin disconnected

Captain : Ok we have two good starts, clear to disconnect the Headset and we'll see you on the left with the pin

Ground : Cleared to disconnect, see you on the left with the pin, have a good day, god bless, best of luck or if you want just a simple bye.

Headset person will walk to the front left of the a/c at a 45 degree angle to the nose, give a wave and walk off

bkehoe

coylemj wrote: »

Question for commercial pilots.....

Do all passenger airlines land manually i.e. is the autopliot always disengaged a matter of seconds before touchdown? I have heard that an automated landing is usually hard so the pilots prefer to manually land the plane.

It's no harder than an average landing. Though the wind limits are much lower than for a manual landing and we have to increase the landing distance required by over 100m when doing an auto land.

Also, one cannot just do an auto land to any runway; it requires an ILS for example. And many airports only have a basic ILS (CAT1) which does not provide the accuracy or reliability (backup power systems for the ILS, runway lights, etc) to perform an auto land in low visibility. One can still auto land to a CAT1 runway but only to standard minimums, in VMC, and when closely monitoring the automatics and ready to disconnect the autopilot if it does something weird.

There are also several airports around with glideslopes out of the limits for an auto land on my type anyway (too steep, never come across one too shallow!), so one can't even do a 'practice' to them.


With regard to when one disconnects on a normal approach; depends a lot. I personally like to use the automation as much as possible until all the configuration changes and checks are complete around 1000ft as its a very busy period these days where low drag approaches are so common (e.g. gear only going down at 4 or 5 miles out, etc) and then landing checklists being run. If its CAVOK or benign weather and quiet airspace then I'm happy to fly quite a lot more manually. On the other hand, sometimes flying manually if the weather is really bad and gusty seems to work better.

conor_ie

billie1b wrote: »

The conversation goes :

Captain : Ground to flight deck

Ground : Flight deck go ahead

Captain : please confirm all checks complete and bypass pin installed?

Ground : All checks complete and bypass pin is installed

Captain : Ok, we are clear to push and start, call when ready for brakes.

Ground : Clear to push, release brakes please

Captain : Brakes released.

Ground : Brakes released, commencing push.

Captain : Let us know when we are cleared to start No 2?

Ground : Clear 2

Captain : Starting 2, Clear on No 1?

Ground : Clear 1

Captain : Starting 1

Ground : Pushback complete set brakes please

Captain : Brakes are set, clear to disconnect the tow bar, tug and pin, call when disconnected

Ground : Tow bar, Tug and bypass pin disconnected

Captain : Ok we have two good starts, clear to disconnect the Headset and we'll see you on the left with the pin

Ground : Cleared to disconnect, see you on the left with the pin, have a good day, god bless, best of luck or if you want just a simple bye.

Headset person will walk to the front left of the a/c at a 45 degree angle to the nose, give a wave and walk off

Cheers for that billie1b

billie1b

conor_ie wrote: »

Cheers for that billie1b

No probs dude

DeVore

I always wanted to know if you sometimes, just occasionally, sit at the controls and go "brrruruuuuummmmmmmm brumm brumbrum" ... while pretending to drive it.





Cos I totally would!!

keith16

billie1b wrote: »

No probs dude

What's the significance of clear 1, clear 2?

Growler!!!

keith16 wrote: »

What's the significance of clear 1, clear 2?

Lets the pilot know he is clear to start engine number 1 or engine 2.

Aircraft engines are numbered from the pilots left to their right. It avoids confusion as the pilot and ground crew are facing each other. So my left is his right etc.

DownBeaten

billie1b wrote: »

Captain : please confirm all checks complete and bypass pin installed?

Pardon the stupid question, but what does the Bypass pin bypass? Landing gear retraction?

billie1b

DownBeaten wrote: »

Pardon the stupid question, but what does the Bypass pin bypass? Landing gear retraction?

Its the pin that goes into the nose wheel and bypasses the hydraulics, this enables the ground crew tug driver to have control of the wheel so he/she can steer the plane