[ifly]

Originally Posted by revtech

@ifly curious how u calculated 12kmpl.

Hey RevTech...

I skipped the calculation for someone to ask me this. And I suppose you are a pilot or atleast have the wisdom of one, I'll throw in some 'jargon'.

• The fuel consumption on the a320 during cruise with the highest mid-cruise weight is 42 kg per min.

• 42kgs to Lts - 42/0.785 (Specific gravity) = 53.5 Liters

• Which means about 3200 liters per hour.

• Airplane (ground) speed is usually about 450knots = 833 KMPH

• The airplane seats 180+6 crew members.

• Now some assumptions need to be made here. One of them is consider each car seats four.

• 186/4 = 46. 5 cars
• Since 46.5 cars consume 3200 liters to travel 833km one car takes?
• 3200/46.5 = 68.8 liters
• Therefore, 833/68.8 = 12.1 KMPL

I hope this was a reasonable corolation

Originally Posted by alpha1

I know, but I want to know from a Pilot's flying perspective, given a choice of leading edge slat vs trailing edge flap - what would you choose during landing or takeoff from a short runway?

EITHER ... OR, not both.

I would chose slats if I had to chose one, both are always great!

Originally Posted by Guite

There are. Infact neel (I think) was reluctant to start a thread because he was / is afraid that it may degrade to a "my career is better than yours" debate.





Its calculated per head basis assuming each passenger is driving a car. Hypothetically, if each of those passengers were to drive themselves to that destination, cumulative fuel consumed would be more or less same as that consumed in an airplane if they fly together.

Applying same logic a Volvo bus will give in excess of 100km/l. Thats why public transport makes financial and environmental sense. An aeroplane pales in comparison. So a plane while being a mass transporter, is only as efficient as a personal transport.

Perhaps, but consider crossing the Atlantic by a ship... The world perhaps wouldn't be where it is without air travel.

The cost effectivity you're talking about does not factor in the huge amount of time that one saves!

Originally Posted by sukhoi30

Nice thread!! Can you post some more pictures? Ever since I was a child, I was fascinated by airplanes and wanted to see a cockpit of one. I have one question for you ... everyone has experienced the crew asking passengers to turn off electronic devices during take off and landing. (Well, I am not asking about mobile phones) ... devices like ipad, mp3 systems or any other such devices. Can you comment if you have seen any such devices disturbing your flying procedures? And, why do we have to turn them off during takeoff and landing only?

I am terrible at taking pictures. I will try and get some soon : )

I am going to give you a very raw reasoning for this. The integration of electronics have gone even in our microwave. I can very well water my plants in my farm with an app in my phone. Amazing!

Airplanes use these electronics to a very large extent depend on them.

For this reasoning you will have to agree with me and Late Michael Faraday that electricity has some magnetic field around it. Get two devices that have a magnetic feild around them, the magnetic feild will consequently affect the electric semi-condutor that is producing the magnetic feild.

In this case the two components involved are the aviation electronics and the personal electronics that you're requested to switch off.

Hope that helps.

Originally Posted by adarsh.n

Hi iFly, Thanks for posting the video. Hats off to Capt Sullenberger and the control tower crew who kept cool until the end. I can understand you guys are trained for it albeit in simulated environment, but to face it in real life takes a lot of courage and audacity especially when you are entrusted with lives of so many including yours.

As trained as we are, I hope noone ever encounters such a situation!!!

Originally Posted by puchoo

Absolutely fantastic!! Glad you are here , i am a keen aviation buff and i simply love this thread.

Your jet gives a better mileage it appears than by recently acquired (T) Jet

I forget the number of times on has been on an aircraft now thanks to work but even now if i find the flight deck door open i cannot help but look at it , absolutely mesmerizing especially all lit up.

Thank you!

Originally Posted by drmohitg

And the worst part is more than half of the passengers just put it on silent mode.
Also I wanted to know why do the window shades need to be opened while landing and take offs?

Mohit I am glad you're in the other half. Among other reasons added by the distinguished gentlemen, closed windows means an highjack situation.

Incase of cabin fire gives the firemen more awareness of what's happening inside the cabin. All windows open means the whole lot to be seen from outside in.

Fire outside means you can look outside thru all the windows increasing your awareness of what exit to take. Increasing visibility inside out.

Hope that helps.

Originally Posted by wanderernomad

For better visibility, light into the cabin, and you probably want to know what you have landed yourself into.

I agree with this and thank you for it

Originally Posted by naveenroy

Wooowoogohoooo! Can't imagine I missed coming across this thread all these days. Amazing to have a commercial pilot on the forum.

Was damn interested in becoming a pilot until mom kept forcing me to have eggs in the morning as a kid. She said that all pilots have become so only after having eggs regularly. Half boiled.

Hey, that's actually how I prefer my eggs *sill grin*

Originally Posted by i74js

No, the Air France 2009 flight 447 (it was Airbus A330-203) Crash has something to do with the inconsistencies between the airspeed measurements—likely due to the aircraft's pitot tubesbeing obstructed by ice crystals.

The final report was to be released sometime mid 2012, I am not too sure but exact reasons should be availble somewhare.

It's been out. It's a couple of reasons. No pilots should fly with faulty equipment is my take on it. I respect the pilots who have perished and hope the gates of St. Peter welcomed them in.

Originally Posted by plimsollmark

After the blackbox recovery, the final word was sadly pilot error. Here is the full transcript of the cockpit conversation.

http://www.popularmechanics.com/tech...ce-447-6611877

Cheers.

Thanks for sharing

Originally Posted by sandeepmdas

And the pilot error was complimented by the sidestick, which provided no visual feedback.

http://shimonacarvalho.com/design-an...ce-flight-447/

Originally Posted by madhav14

Excellent one and very interesting thread. Awaiting for some more details & experiences from you.

Just a small question from my side. What are the outside temperatures at those altitudes (apprx. 30,000 ft)?
Every time I fly, I always wonder what it would be like to sit on the wings of plane and enjoy the outside scenery


I'm expecting that soon

It's something we call jet standard temperature -56.5

And about enjoying the scenery, this has to be one of the biggest perks of this job!

Originally Posted by raveesh_k

An interesting thread indeed!

"Maverick: Tower, this is Ghost rider requesting a flyby" - I get goosebumps even now when I hear these lines at times.

I had a general question for this forum - In a normal flight I am assuming the maximum Gs that any passenger faces is during take off. What is that number of Gs and what could be the possible variation?

Cheers!

Passenger airplanes are maneuvered in an accord that is the most comfortable. So most of the time about 1.5 at the most.

A "terrible" landing would mean a G factor of about 1.6ish

Originally Posted by yogibear007

I guess it would have to be a very cold observation session indeed. Usually you will have temperatures of around 60/65 degrees negative at this altitude.

Right on Agent 007! More or less : )

Thank you for sharing.

Originally Posted by sagarpadaki

The asynchronous side-stick will be a hinderance when

-> The pilot is not trained to use the feature properly
-> In Panic situations

Combine these two together and you have a perfect recepie for disaster!

I feel that the the side sticks should be synchronous. This will ensure that the pilot will know that the other pilot is doing!

To know that so many lives were lost just because of some stupid untrained pilot pulling the stick back , i feel really bad!

And what business did the commader have to move out of the cockpit to take a break when the plane is facing turbulance?! He should have stayed at the controls unless it was a loo break or something in which case he should have returned back to his seat immediately


EDIT: Any idea if this design is changed in now or is it still the same in all Airbus aircrafts?

He was excercising something called as controled rest. The gentlemen at the helm of the controls did fly, cumulataively and safely, for the preceding 10,000 hours. Unfortunately... Ah well...

On the note of sidestick and the yoke... I think both are great ways to fly the airplane!

Apologies to the boeing buffs but,

Here's the most advanced airplane boeing makes. The F22 Raptor.

http://avioners.net/wp-content/uploa...lluminated.jpg

Notice that it uses a side-stick! Haha!!

PS: If I have not replied to any of the queries, please pardon thy limited attention span.

Note from Support - Post edited. References to alcohol are not allowed even indirectly.

[bsdbsd]

iFly and other pilots on the forum,

Thanks for this thread and the continued contributions making us smarter than what we were yesterday! Big Thanks to T-BHP as well, as always.

I am shamelessly using this opportunity to ask you some questions. Please feel free not to answer.

1. On takeoff, until you reach the cruise altitude, will you hold a constant vertical speed or attitude or aircraft speed? What will be put on AP?

2. What is the maximum rate of descent followed by commercial pilots in India (and elsewhere)?

3. Why do think 4 (four!) Asiana pilots mess up the visual approach on a clear day in SFO? (See how I am demanding answers :-) ). What kind of human factors are at play in your office (cockpit).

Thanks.

[ifly]

Originally Posted by bsdbsd

iFly and other pilots on the forum,

Thanks for this thread and the continued contributions making us smarter than what we were yesterday! Big Thanks to T-BHP as well, as always.

I am shamelessly using this opportunity to ask you some questions. Please feel free not to answer.

1. On takeoff, until you reach the cruise altitude, will you hold a constant vertical speed or attitude or aircraft speed? What will be put on AP?

2. What is the maximum rate of descent followed by commercial pilots in India (and elsewhere)?

3. Why do think 4 (four!) Asiana pilots mess up the visual approach on a clear day in SFO? (See how I am demanding answers :-) ). What kind of human factors are at play in your office (cockpit).

Thanks.

• Speed.
• Normally about 1500 to 2500 feet per min but not limited to that

It's brilliant that you used the word human factors. Also, if I may this was not a "pilot error" but rather, a human error.

I am not very sure why they would have done such a thing!! Quite honestly, I am very keenly waiting on the findings myself.

If this subject matter interests you, i suggest the following read:

http://www.flipkart.com/naked-pilot-...mdymfgtsqbzuh9

Whenever it is in stock

[sagarpadaki]

Originally Posted by ifly

He was excercising something called as controled rest. The gentlemen at the helm of the controls did fly, cumulataively and safely, for the preceding 10,000 hours. Unfortunately... Ah well...

On the note of sidestick and the yoke... I think both are great ways to fly the airplane!

Apologies to the boeing buffs but,

Here's the most advanced airplane boeing makes. The F22 Raptor.

http://avioners.net/wp-content/uploa...lluminated.jpg

Notice that it uses a side-stick! Haha!!

I am not against side sticks. I am talking about the asynchronous nature of the side stick which can lead to problems in panic situations. Its like you don't know what your hands are doing and each of them has a mind of its own!

And the raptor is a single seater i believe. So asynchronous side stick or not does not matter because there is not other contention on the control surfaces

[liferocks]

Originally Posted by bsdbsd

iFly and other pilots on the forum,

1. On takeoff, until you reach the cruise altitude, will you hold a constant vertical speed or attitude or aircraft speed? What will be put on AP?

2. What is the maximum rate of descent followed by commercial pilots in India (and elsewhere)?

3. Why do think 4 (four!) Asiana pilots mess up the visual approach on a clear day in SFO? (See how I am demanding answers :-) ). What kind of human factors are at play in your office (cockpit).

Thanks.

1. After Take off we do not maintain a constant vertical speed or aircraft attitude. we fly speeds. IAS ( Indicated air speed) in knots till crossover altitude and then fly in mach. Crossover altitude is where speed changes from knots to mach number and is different for different aircrafts. The speed to fly is generated by Flight Management Computer, and is dependent on many inputs such as aircraft weight, enroute winds, ISA deviation at planned altitude and cost index etc.

2. Maximum rate of descend.. well never thought about it this way. Generally commercial flights focus on passenger comfort and hence we descend at about 2500 feet per minute or so, which ofcourse depends on speed also. However my company takes anything more than ROD 5000 fpm as flight safety violation unless an emergency requires so.

3. I think it was a TV channel which messed up with the pilots' names rather. But seriously it would be too amatuer to comment on the reasons since we do not have access to the finer details.

Regards

[sreejith.pish]

I was presumably surprised to see a review of a A320 in the Team BHP.
Its an awsome thread.

From a layman's point of view, I have allways considered Airbus as a people-carrier and Boeing as being the sportier one. This may be because Airbus is actually named Air"Bus".

After some googling, I understood that the A320 has been selling larger numbers than Boeing 737 since 1996. I would like to know more on A320 vs B737 and why the Airbus sells more than the Boeing.

Thanks for sharing the thread

[phamilyman]

Originally Posted by ifly

http://www.flipkart.com/naked-pilot-...mdymfgtsqbzuh9

Whenever it is in stock

OR, you could buy it NOW!

http://www.amazon.in/The-Naked-Pilot...4586066&sr=1-4

317 bucks for the kindle edition vs the 4x costlier paperback!

Thanks for this thread - quite a few nuggets even for the frequent fliers like us! On a side note - Any way for us to drop in and say hello to you if we're flying Indigo? Surely you don't announce iFly on the PA system, right?

/if it was an Air India A320, the mileage would've been around 9-10 KM/L given their load factors

[ifly]

Originally Posted by sreejith.pish

I would like to know more on A320 vs B737 and why the Airbus sells more than the Boeing.

Thanks for sharing the thread

Well those are tightly gaurded secrets that a very few handful know.Both these airplanes are brilliant. I am sometimes am biased towards airbus because I have been flying the 320 from the last 5 years but I can never chose one over the other. They are just flying testimonials to what human engineering can achieve!

So the only thing that boils down to is the economics. Which manufacturer is desperate to sell you more. How negotiations end up!

The owner of RyanAir in Europe played his cards so well that after sometime when RyanAir hinted they want to buy Airbus a320, Airbus simply said they are not interested! haha!

Originally Posted by phamilyman

Any way for us to drop in and say hello to you if we're flying Indigo? Surely you don't announce iFly on the PA system, right?

Haha! I would like that very much. I just announce iFly followed by the flight number only on the radios while talking to the ATC.

Regards,

Vinayak Raghubir Sharma

[Jeroen]

Originally Posted by revtech

there is no RTO "button" , its a maneuver. which begins with thrust levers to idle and thats when the autobrakes engage only if the speed is higher than a pre-determined value.

Well it all starts by pressing or setting a switch to RTO, certainly in a Boeing, but even in an Airbus you must tell the system you're going to take off and you need RTO mode armed. That's a switch or a push button somewhere on the pedestal isn't it.

Once RTO is set/armed you will be able to execute the maneuver as you described.

I have just found some PDF files of my KLM 744 AOMs and they show a bit more elobarate mode of interlocking, including ground mode sensing for landing and take off (RTO) mode. Still, lets leave it at this, because I'm not sure how useful this much detail is for most of the members.

I'm getting the relevant Airbus AOM pages mailed to me in the next couple of days.

Jeroen

[sreejith.pish]

Originally Posted by ifly

Well those are tightly gaurded secrets that a very few handful know.Both these airplanes are brilliant. I am sometimes am biased towards airbus because I have been flying the 320 from the last 5 years but I can never chose one over the other. They are just flying testimonials to what human engineering can achieve!

Thats a very diplomatic answer.
In case of cars, there are so many options and so many reviews, opinions. We are a spoiled lot here. Thanks anyway.
Voted 5 star

[prancinstallion]

I'm glad that i just bumped into a post as unique as this one. Aviation buff? Thats soo me..
I ve made frequent trips but Im no frequent flier but every time I walk along those glass facades overseeing the parking bays and runways its a feeling of deja vu. Watching the luggage carts getting loaded into the underbelly, pre-packed meals into the pantry et al is so intriguing, not to forget the pre flight routines that the gentlemen(and women) make in the hot seats. Having boarded the massive A380 few times, whose magnanimity never ceases to amaze me especially while looking at those huge engines, walking down the aerobridge to board the plane. However this post is not about my experiences, but of "iFly" and other pilots.

Before jumping onto the routine of asking Qs, I would like to appreciate a post like this by 'iFly' and inputs from other pilots.

1) Everytime you guys take to the skies, is there a feeling of flying your extended family to a destination or are you emotionally disconnected?

2) Cruising at those altitudes, did you ever have a Eureka moment where in you thought that this could change the way we fly?

3) Do you get any brownie points for maintaining an impressive fuel efficiency?

Excuse if they sound silly or stupid or both.

[Jeroen]

Originally Posted by ifly

PS: If I have not replied to any of the queries, please pardon thy limited attention span.

In one of your earlier post you mention
QUOTE
It may come as a pleasant surprise to you, but the Indian skies are the most stringent to fly in, making them perhaps the safest! Much more than even the US.
UNQUOTE

I would be interested to understand what makes the Indian skies the most stringent to fly in? What is different compared to say the US or Europe. And other than having stringent regulation, are Indians sky safer??

Originally Posted by liferocks

1. After Take off we do not maintain a constant vertical speed or aircraft attitude. we fly speeds. IAS ( Indicated air speed) in knots till crossover altitude and then fly in mach. Crossover altitude is where speed changes from knots to mach number and is different for different aircrafts. The speed to fly is generated by Flight Management Computer, and is dependent on many inputs such as aircraft weight, enroute winds, ISA deviation at planned altitude and cost index etc.

I'm not familiar with Airbus really, but on Boeing with Honeywell FMS there are essentially two vertical speed modes VNAV and FLCH. Broadly speaking VNAV will get you the vertical speed you need between two waypoints with different altitudes and FLCH will give you a certain set vertical speed ascending or descending, irrespective of lateral profile.

Does the Airbus have someting similar or is it very different. My impression is that the Airbus different modes seem to be more complex.

Jeroen

[revtech]

Originally Posted by Jeroen

I'm not familiar with Airbus really, but on Boeing with Honeywell FMS there are essentially two vertical speed modes VNAV and FLCH. Broadly speaking VNAV will get you the vertical speed you need between two waypoints with different altitudes and FLCH will give you a certain set vertical speed ascending or descending, irrespective of lateral profile.

Does the Airbus have someting similar or is it very different. My impression is that the Airbus different modes seem to be more complex.

Jeroen

On Boeings there are three modes actually VNAV, LVL CHG, VERT SPD.

Vnav follows a set speed and path.
LVL CHG will give you a variable vertical speed while maintaing a constant IAS.
VERT SPD will fly the set vertical speed with varying IAS.

the latter two modes are completely independent of the FMC.

Originally Posted by Jeroen

Well it all starts by pressing or setting a switch to RTO, certainly in a Boeing, but even in an Airbus you must tell the system you're going to take off and you need RTO mode armed. That's a switch or a push button somewhere on the pedestal isn't it.

Once RTO is set/armed you will be able to execute the maneuver as you described.

I have just found some PDF files of my KLM 744 AOMs and they show a bit more elobarate mode of interlocking, including ground mode sensing for landing and take off (RTO) mode. Still, lets leave it at this, because I'm not sure how useful this much detail is for most of the members.

I'm getting the relevant Airbus AOM pages mailed to me in the next couple of days.
Jeroen

there is no push button, you just set rto on the autobrake. the airplane is capable to understand its rejecting a take off you dont have to tell it. it computes throttle position sudden deceleration etc.

its a little two advanced in depth for a layman so i decided to keep it out of the discussion i guess you agree now..!!

but since you brought it up the air/ground sensor etc are only applicable for arming the autobrakes in its respective modes. not activation of the same..

why go through the trouble of having them mailed .just ask ifly..

Originally Posted by ifly

Hey RevTech...

I skipped the calculation for someone to ask me this. And I suppose you are a pilot or atleast have the wisdom of one, I'll throw in some 'jargon'.

• The fuel consumption on the a320 during cruise with the highest mid-cruise weight is 42 kg per min.

• 42kgs to Lts - 42/0.785 (Specific gravity) = 53.5 Liters

• Which means about 3200 liters per hour.

• Airplane (ground) speed is usually about 450knots = 833 KMPH

• The airplane seats 180+6 crew members.

• Now some assumptions need to be made here. One of them is consider each car seats four.

• 186/4 = 46. 5 cars
• Since 46.5 cars consume 3200 liters to travel 833km one car takes?
• 3200/46.5 = 68.8 liters
• Therefore, 833/68.8 = 12.1 KMPL

I hope this was a reasonable corolation

lol.. kind of figure that out. i would have just said 2200 kgs/hr

thats assuming 4 ppl go in each car.. on an average that prob would be less but i get your drift... cheers

[siddarthbh]

Loved seeing this post here on Team-BHP. As an aviation enthusiast and aviation photographer, it did bring a smile. Brilliant review of the Airbus A320 along with technical answers to questions. Looking forward to more pics from your office.

On a different note, have you gotten a chance to fly on the newer 6Es with the Sharklets. I guess there are about 10 in the fleet right now?

[Jeroen]

Originally Posted by revtech

but since you brought it up the air/ground sensor etc are only applicable for arming the autobrakes in its respective modes. not activation of the same..

According to the KLM 744 AOM:
In flight and ground operation of various airplane systems are controlled by the air/ground sensing system and a nose gear extension sensing system.
All four main gear tilt as the airplane lifts off the runway. When a combination of main gear tilt sensors indicate the gear are tilted (air mode) or not tilted (ground mode), an air/ground signal is provided to relays which control various system functions.
Nose gear extension sensing provides a signal to relays controlling functions in the stall warning and nose gear steering systems.

So I don't think the air / ground system has anything to do with arming of the system. Maybe semantics, but I read it as a pre condition before any of the other system logic kicks in. The only reference I can find to "arming" the autobrake system is in the check list for take off and landing and that's is just setting the auto brake to a particular value or RTO. Other than that it can be in the off or disarm position.

Just another question; It is mentioned that the auto brake kicks in after wheels spin up, maybe a few other preconditions to be met as well.

Still, I never fully understood the wheel spin up. Wouldn't it make more sense to have main gear strut deflection and spoiler deployment as criteria? When those two conditions are met you know for sure your aircraft has planted its gear/wheels firmly on the runway. Wheel spin up starts as soon as the wheels start touching the runway. If you do a landing like the first video, I can imagine you sent the ABS system into a frenzy, or burn rubber before your braking becomes effective.

I've read in the Airbus documentation stating that the brake pressure initially builds up gradually to reach the value of its preset deceleration. Maybe that prevents the above. I haven't read anything like that on the Boeing? Seems to kick in at the preset value period!

I'm sure there must be some logic to it, but I don't see it yet. The diagrams I have of the 744 actually suggest there are switches on the gear struts that do play a role in the interlocking conditions. I just can't tell exactly how. Wouldn't be the first time that an AOM show a simplification of what technically happens. As long as it is functional to the pilots it should be alright I guess.

Jeroen