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Are Flex / De Rated take offs safe?

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Are Flex / De Rated take offs safe?

Old 25th May 2008, 17:18
  #141 (permalink)  
F4F
 
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Devil We want to learn!

Well tankdriver45, Angels 60 and other SSGs, now having so convincingly proved your worth by showing the world (of PPRuNe) how safe your operation is, you surely won't mind sharing with us some other ways you "improve" the safety of your daily flying, will you, please, please (some ideas: mandatory 3 hours flight prep, 10T extra fuel each leg, lower FL to increase TUC, no flights if any risk of CBs or icing, increased DH/MDA for each approach, VMC only flying, HW only departures and arrivals etc, etc, remember those are only a couple of pointers )


live 2 fly 2 live
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Old 25th May 2008, 17:29
  #142 (permalink)  
 
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Brace, think about improved climb performane. We use it pretty often now, but it is somewhat uncomfortable to learn since you get very high Vrs with usual V1s and rotations in the red lights are usual even on 4000m runways in lightweight 733/737-7.

However you actually increase safety that way since you have a much better initial climb performance and with usual V1 more than enough space to abort if you get any problems before that. We are still climb limited with it, but it allows us to carry several tons extra or reduce thrust even more.
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Old 25th May 2008, 21:56
  #143 (permalink)  
 
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GIV drivers, if they work for a publicly traded co., have some incentive to optimize costs. I know this from the local DJIA co. operations.

On the other hand, if a private company, often they have a freer hand to play with their toys - GIVs or bigger, mega-yachts, etc. I have a guess which category ssg etc. flies.

My 10R once went on busman's holiday in NZ - he said there's a substantial cottage industry in the City of Sails, doing home theatre installations in visiting mega-yachts!
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Old 26th May 2008, 18:25
  #144 (permalink)  
 
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Denti, we only use the improved if we're climb limited and can't make it the normal way. But we don't reduce the thrust then, so there's some increased safety most of the time, I agree.

I've heard of airlines using improved as a standard, then of course you always have extra margin if you were climb limited. On long runways this creates indeed a big safety margin.
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Old 26th May 2008, 18:44
  #145 (permalink)  
 
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Yep, we're one of those, pilots discretion though. We can combine derate, assumed, improved climb and forward CG performance if we really want. On long runways that can get very weird results and ATC isn't really happy when we have a longer groundrun than a fully loaded A340.
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Old 26th May 2008, 21:03
  #146 (permalink)  
 
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Denti why would you try to use derate and assumed then improved climb????

Improved climb is used when you have excess TORA available and the higher speeds allow you to lift more weight, hence you wouldn't be assuming and the chances of derate would also be lower.
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Old 26th May 2008, 22:09
  #147 (permalink)  
 
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Well, yes, if you want to lift more weight. However if you have a given weight and want to use less thrust despite being climb limited improved climb is a way to achieve that. The downside is that you use a lot of runway and get very high Vr and V2 which in turns increase runway occupancy time considerably, hence ATCs dislike of that practice, especially on crowded airports. By the way, V1 is not higher than normal and can even be lower since Vmcg is lower due to a derated thrust setting.
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Old 27th May 2008, 11:07
  #148 (permalink)  
 
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I've heard of airlines using improved as a standard
Its part and parcel of flying an Airbus...... Optimized V-speeds ....

Mutt
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Old 27th May 2008, 16:54
  #149 (permalink)  
 
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F4F,
Me being away for a few days and he already got another user id and got banned too? I must have missed a lot.

I guess next, he would be arguing that the Brussels Kalitta is a case of dangerous derate!
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Old 27th May 2008, 22:52
  #150 (permalink)  
 
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His deleted post from his banned personality should be a stick in JB---he now has me rolling;

RTO's after V1, but attempting to fly off BLO Vmc
Decents blo MDA/H
and landing in the face of TS's

LOVIN IT

PA

Last edited by Pugilistic Animus; 27th May 2008 at 23:27.
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Old 28th May 2008, 00:00
  #151 (permalink)  
 
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his imput has taken what is a very boring forum and made it very interesting? Don't you think?
No, that's why he was banned. His input contributed nothing.

You've very recently joined, I see...
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Old 28th May 2008, 00:05
  #152 (permalink)  
 
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I see Guppy got fooled again
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Old 28th May 2008, 01:31
  #153 (permalink)  
 
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He's a sly one, alright. Nearly as subtle as a wounded ox during mating season in a briar patch full of stinging nettle and horseflies. Nearly.
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Old 28th May 2008, 06:22
  #154 (permalink)  
 
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Angel

Do I see SSG v4.0 ?
Interesting v4.0 joined as soon as v3.0 was banned.
And always links the current version with the previous ones.
Yes, it makes it interesting albeit frustrating and painful...
but after seeing the same patterns again and again, sorry, SSG, it's getting boring.

I guess this one has tooo much time on his/her hands... corporate or not, pilot or not.

I think someone should make a "Bad Flying Advise" series and shove what Ssg and his "successors" preaches there... well, it'll be bad advise for those who carry cattle class (aka cattle flyers aka SLFs) at the back.

PK-KAR
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Old 28th May 2008, 06:45
  #155 (permalink)  
 
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Of course it's safe.... Purleez..
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