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What Cost index are you using B737NG?

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What Cost index are you using B737NG?

Old 6th Oct 2011, 12:39
  #41 (permalink)  
 
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So what is the airline saving if they are paying their pilots 500 Euro/month. Last time I checked there are usually more pilots then jets. I'm not against any pilots getting paid more but this doesn't make much sense unless I have missed something.

FH
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Old 6th Oct 2011, 13:28
  #42 (permalink)  
 
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Reference to passengers not noticing the difference between a 310 to 320 speed decent versus a path descent on a cost index of 11 (circa 250 kts.) is not true. The noise level at the higher speeds is noticeably higher and pitch angle is quite lower (about - 2 1/2 degrees) versus a virtually level nose attitude with a calmer rate of descent.

Also, the cabin crew will appreciate that slower rate of descent when negotiating those galley carts up and down the aisles during stowage for landing. Ever experience a galley cart slamming into the cockpit door? I witnessed it whilst sitting the back of the jet during a high speed descent. Luckily the galley cart went straight for the cockpit door and did not careen into any of the sponsors who make our paychecks possible.

Anyway at the end of the day is a two minute savings in flight time really worth the effort of causing discomfort and a possible difficult working environment for those behind the cockpit?

As I get paid by the minute, I have no great need to push my jet to it’s designed limits… that’s what the test pilots get paid for. Anyway… food for thought.
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Old 6th Oct 2011, 14:10
  #43 (permalink)  
 
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Framer,
Joining the rank of immature remarks too?please...
Captj,
True, i really started to think than i was the only one feeling the effect of those high rates of descent..but seems like a few testosterone filled pilots with latest noise canceling headsets tend to forget that the people behind are those paying their wages and that their passengers dont fly regularly nor average 20 year of age.
Concerning the fuel saving bonus,yes,some airlines do pay you based on your monthly fuel saving,everybody wins...

Last edited by de facto; 6th Oct 2011 at 14:20.
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Old 6th Oct 2011, 21:17
  #44 (permalink)  
 
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Joining the rank of immature remarks too?please...
No. No not at all. I would genuinely like to know how you find it.
It is generally thought that it effects some pilots motivation in a negative way re safety. The thought is that when presented with two options and the safest one uses more fuel, that it makes it that much harder for the pilot to make the correct choice. Go-arounds are a good example. So is diverting around weather. Most pilots are fairly determined and don't like to give up easily, they also don't like changing the plan, thats why so many approaches are continued around the world that were unstable at 500ft and a go around should have been conducted. Now add to our already feeble decision making abilities the thought of losing some of that precious 500 euro, and the correct decision becomes less likely.
I was anting to know how you combat this, and how other pilots in your airline combat it. That is all, no need for silly faces.
Framer.
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Old 6th Oct 2011, 22:39
  #45 (permalink)  
 
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De Facto, To demonstrate that my query was genuine and not in any way facetious,(or immature as you said), I have cut and paste from the trial of a Garuda Airlines Captain who was charged with the deaths of 21 people.


Komar's trial for criminal negligence over the deaths of 21 people in the crash, including five Australians, begins today. He has never spoken publicly about the Boeing 737's descent, but his police interrogation report, which is central to the case, has been obtained by Herald.


Under questioning, Komar said there had been arguments with his co-pilot during the landing. He admitted the plane touched down at an unsafe speed.


He said he was concerned about conserving fuel -
Komar said he compromised with his co-pilot, Gagam Rahman, on the level of flaps the plane was using on descent because "by using a flap of 30 degrees the usage of fuel was relatively not much". Garuda had introduced large bonuses for conserving fuel shortly before last year's accident.
It was my understanding that the practice of rewarding pilots financially for fuel savings was understood to be a Human Factors disaster and that no reputeable airline did so anymore. It is akin to 'dive and drive' techniques v's the now accepted constant decent approaches, in that it is a recognised threat to safety.
That was my understanding. Feel free to correct me, I am always open to new learnings.
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Old 7th Oct 2011, 08:39
  #46 (permalink)  
 
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Framer,
As far as i am concerned,if a go around or diversion is necessary i will do so.
Fuel saving in my mind has no effect on my judgement of safety.
If diversion is made,extra fuel burn is not accounted anyway...
500 euro is good but really pocket change compared to our paycheck.
I rarely take extra fuel as the minimum fuel on flight plan is already quite generous compared to low cost i flew for in europe,if the crew decides to add fuel no question are asked,at least personnaly i never got questionned.

My airline takes safety very seriously,and having done 3 diversions due to airport overcapacity,and a go around, i have never been asked any question for the reason of such action or why a go around was performed.
Our sops dictate 1000 ft to be fully stable imc and vmc, if not a go around must be performed.
Concerning flying around weather,i am very conservative and can say i never got into a dangerous situation nor stroke by lightning,as you may have noticed about the speed issue, i like confort as much as the passengers.
However 90 percent of time, fuel saving is possible and i will do all i can to do so,within a confortable safety net.
Crews are very closely monitored and cowboys get spoted very quickly and put back into place.
So yes im sure this bonus has no impact on safety decision within my airline.

Last edited by de facto; 7th Oct 2011 at 08:59.
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Old 7th Oct 2011, 10:49
  #47 (permalink)  
 
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This thread has drifted miles of course and that is partly my fault. Let me explain why I fly high speed all the time. I work for a (in)famous European airline that has zero respect for me or any of my colleagues. I am based in a awful base in southern Europe where the company regularly leaves the block times at least 10 minutes shy of what they should be due to a 20 minute taxi that they don't and won't take into account. As I get paid by the scheduled block hour I have no intention whatsoever of flying ECON speeds and get shafted once again by these useless shower of clowns. I am a FO and I always ask the skipper first if he is ECON or high speed. If he says ECON I respect him and do it his way but I would say 80% tell me to fly as fast as I want as long as I don't break anything I have even had some Captains bark at me for NOT doing 330/.81. But then again if we were paid by the actual time and the airline treated us with a bit of respect we would gladly respect their fuel policy and do that wonderful 273 KTS descent
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Old 7th Oct 2011, 20:16
  #48 (permalink)  
 
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Defacto,thanks for the answer. I have another question, is FOQA part of the reason your airline can operate this policy without influencing the decision making of the pilots? Cheers and thanks for the apology

Jonnytighty, Your airline sounds terrible man. I can't understand management like that as it's such a false economy. It would be much cheaper for them to pay an extra 20 mins block time and not have a p1ssed off pilot group.
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Old 8th Oct 2011, 06:57
  #49 (permalink)  
 
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Framer,
Please accept i withdraw my initial remark.
Now, Pilots are humans and all have different views on the matter(foqa),however flying at .081/330 just because one doesnt get paid for the extra time doesnt show AiRMANShIP(a word despegue seems quite fund of)nor a great sense of professionalism or maturity.

Im sorry johnny has to endure this on a daily basis but i hope when he will eventuallly upgrade he wont follow such way of thinking.

Last edited by de facto; 8th Oct 2011 at 09:04.
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Old 8th Oct 2011, 12:42
  #50 (permalink)  
 
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Qantas 737-800 Cost Index.

Hi chaps. What Cost Index is Qantas using for it's 737-800's? Would love an answer. You can Private message me, I promise I wont tell anyone if you don't want me to. Thanks.
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Old 8th Oct 2011, 15:00
  #51 (permalink)  
 
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Johhny tight lips :

Well I am surprised you are still here, but probaly won't be for too long. People likes yourself usually have little backbone and are all mouth Who often fail their annual line check and command upgrades. and rightfully so as you seem to show little airmanshipn or professionalism. With your attitude little Sympathy simpify can be felt towards yourself.
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Old 8th Oct 2011, 15:49
  #52 (permalink)  
 
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300kts+ burns more fuel than 250kts, for the reason that less time is spent at idle thrust. You might not feel that the small fuel saving is worth it but your employer might disagree and it's simply poor practise. Think of the extra fuel consumed on a cumulative basis.

I bang my head against the wall (metaphorically, of course) when I see guys quite correctly flying a variable, CI-generated, econ speed throughout the cruise...yet dogmatically sticking to a fixed (and invariably higher) speed in the descent. It burns extra fuel, may save you two minutes at best and is weirdly inconsistent; just fly econ speed unless ATC says otherwise...
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Old 8th Oct 2011, 19:29
  #53 (permalink)  
 
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It allways amazes me how many First officers want to fly on the longer routes from the Canaries at .80/.81 ,only to find out when told NO that the time saved is only Eight minutes versus an extra Ton of fuel burnt. No thanlks !!!!!!!! the Cruise is for reading the Papers and magazines not waiting for a tech log entry for Airspeed exceedence, Dont even get me going on energy management for those that want to descend at .80/.81 into a jetstream
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Old 8th Oct 2011, 19:35
  #54 (permalink)  
 
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The problem with a .80/320 decent is that if the winds are not as forecast or ATC changes you speed or route (like cutting a corner) you will find yourself high and the jet will nose over to capture the path. At .80/320 you will find yourself out of Vnav path in short order struggling to get back on the path in order to make the crossing restriction.

I see no reason to plan a high speed decent. If you plan a .78/280 decent The Vnav will plan an earlier decent path. You can push up the power if you desire and fly .80/320.

We use a CI of anywhere from 12 to 99 depending on my dispatchers plan. I routinely override the cruise speed from ECON to LRC to get a higher cruise mach at lower CI'es. For example, with a CI of 12 a typical cruise mach is .76. If I manually select LRC the cruise will pick up to .79. I'm paid by the minute but don't like to spend one more minute at work than necessary.
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Old 10th Oct 2011, 12:25
  #55 (permalink)  
 
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I routinely override the cruise speed from ECON to LRC to get a higher cruise mach at lower CI'es. For example, with a CI of 12 a typical cruise mach is .76. If I manually select LRC the cruise will pick up to .79.
Personally I don't really get that. The airline obviously has spent time and money organising a system that determines the c i they want you to use on that particular sector. This will be based on their labour costs and their engineering costs and their fuel costs. So why don't you use it? If your airline does 180 average length sectors a week, a 100kg fuel saving on each flight is 18 tonnes a week , 936 tonnes a year. Thats a lot of gas.
Determining cost indexes seems quite complicated, on one flight MRC (c i zero and min fuel burn) can be .745 with a LRC of .778, and the next flight MRC can be .77 with a LRC of .79
On the latter even c i 60 will be slower than LRC.
If you aren't late I can't see any good reason to fly faster than the c i that the company has spent time and money determining.
Is
I'm paid by the minute but don't like to spend one more minute at work than necessary.
your only reason or is there something else?
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Old 10th Oct 2011, 13:18
  #56 (permalink)  
 
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At the end of the day... what's to be gained by flying at .80 and 320 Kts on descent? Noise and discomfort the folks in the back of the jet. Do you really save that much time? No.
Now if you're talking about the 727... different story. The 727 can easily lope along at .875 without breaking a sweat... Time will be saved over .78 cruise with quite a fuel burn penalty. But flying cargo back in the day cost was not the motivation... on time performance was.

I'm no boy scout by any means... however, I'm always thinking about how much extra gas I can keep in the tanks if there's a bit of extra holding at my destination regardless of weather conditions.
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Old 11th Oct 2011, 06:34
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Thats exactly it. having the fuel in the tanks at the destination is far better than saving Six minutes over 4 hours.
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Old 11th Oct 2011, 06:58
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Previously the company used CI 30 on all B737 flights and a fixed CI in other fleet types as well. Fleet Manager - Chief Pilot did not understand that the CI should vary on a daily base. "Someone" else decided not to purchase that with the planning software. All CFP´s where made with a fixed CI 30. Sadly but true that was mainly because of the culture there.

Descend planning was .78/280 and changed in the FMC descend page.

In the present outfit we use diffrent CI´s on all Fleet and for each flight a new calculated one, that is reflected on the CFP and inserted into the FMC, the climb descend speed is also changed manualy according the CFP.

That speaks for A320, B737NG and B777´s as I have seen it lately.

Fly safe and land happy

NG
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Old 11th Oct 2011, 07:34
  #59 (permalink)  
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De facto:
I save time on the ground and try to get shorter routings and optimum levels to save time...not flying at m.080/320.
Seems smart to me.

Saving 1 minute on a flight but monitoring the speed like crazy when flying at mach 0.80, no thanks. it's not worse it.

Yes there is a cost index, but .76 and 280 are speeds that respect safety (turbulence), and like to use them.

However at high speed, the cockpit noise difference is more important than in the cabin... Smooth transition is the key, hard to beleive the speed is a confort factor when no turbulence...
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Old 11th Oct 2011, 07:49
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Simple, if you are a comuter trying to make a connection home cost index should always be zero. Otherwise do what ever the company wants. Quite simple actually.
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