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Are Flex / De Rated take offs safe?

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Are Flex / De Rated take offs safe?

Old 21st May 2008, 15:54
  #101 (permalink)  
 
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Guppy

I posted this at the end of the other thread !

>So now that you are back peddling, please answer the question, how do you ensure your obstacle clearance following an engine failure? (referring to SSG)<

Mutt

A few years ago I was involved with a forum for Microsoft Flight Simulator. I did some development work with addon companies, wrote reviews and was fairly active in their forums.

The problem with all these forums is that they are open to a lot of people who hide behind a cloak and claim to be something they are not.

There was one guy in particular who challenged the real world pilots on those forums and fair enough some of the stuff he came up with was quite convincing.

But in other ways his approach was very purile and he made major blunders.
We discovered that this experienced so called pilot was infact a 12 year old kid who was merrily googling his answers on the internet and somehow getting a kick by playing out his act. He fooled a lot of airline and corporate pilots for some time.

Pace

Last edited by Pace; 21st May 2008 at 16:59.
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Old 21st May 2008, 16:05
  #102 (permalink)  
 
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I'll give an ultimate example-US Navy

Fighters routinely catapult off the ship in "cold" power (non-afterburning) to save engines, better control, the F-14 had better stagnation margins. What is the problem? In fact, in the 14, pilots wanted to use cold power, due to engine stalls ingesting steam.

GF
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Old 21st May 2008, 16:36
  #103 (permalink)  
 
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Denti - You got my answer
Indeed, no, you didn't answer my question.

You told us all that
Corporate is the safest sector...look it up...
, so i asked you to provide the figures. After all the only figures provided are from the NTSB proving that indeed exactly that part of aviation produces 10 times as many accidents as airline aviation.

So you still have to provide the answer to my question: Where are the figures proving that corporate aviation is the safest sector in all of aviation.
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Old 21st May 2008, 17:07
  #104 (permalink)  
 
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You and I know guys are using Flex, planning right into the stopway.
Who says when using flex U HAVE to take the stopway into account?

and that is why they fly right over the fence and call it legal.
Right over the fence? hey, if I get an engine failure at V1 and make 35ft or higher at the end of the runway (and higher over the end of the clearway), with no other obstacles in front, good enough for me. If the obstacles become a problem if I derate and have N-1 @ V1, and the non-derate clears it, why should I derate?

Only an idiot, or someone that truly doens't care about safety, or the passengers in back...would time after time choose to burn up more runway then he has too because 'corporate says we will save some money'. I mean what kind of a tool, would believe that ending up at the end of the runway, with and engine on fire , with only a thousand feet to go, then a stopway is safer then having another 4500 ft to go
If you're implying that everyone derates to the extent that it won't meet their TODR and ASDR, then you're the idiot. You can derate to the extent that your TODR and ASDR matches TODA and ASDA (you can include or not include the stopway, your choice)... Of course, for you, it's not safe because using that method you cannot abort past V1 eh? Btw, how much past V1 do you want to abort anyway? Vlof? V2? VMBE? Vmo?

To put it simply, you can only derate as far as the resultant take off and climb profile meets the regulations! Now if you think the regulatory requirements of "flying off the fence everytime" then change the regulations... Shoving a higher screen height, you can still derate!

Guess what, derate to the extent that you still got a spare, means you have a lower Vmcg, so derate to the extent that your ASD and TOD still gives some spare (without the use of stopway) with VMCG as your V1, and will be able to fulfill your seemingly lifelong ambition, that is to abort past V1 everytime and still stop in time!

Who you trying to kid anyways? The Teletubbies?

There was a case here where an engine is known to have high EGT (it was creeping up with each take off), and the ops guys with the maintenance guys wants to pull the engine off line. The aircraft came in for a C check. It was estimated that the maintenance would cost 30k USD. Another aircraft was coming out of maintenance, but the engines hadn't finished, the management insisted to get the aircraft flying at all cost despite the ops and maintenance guys saying no.

It was going to be a long weekend, and extra flights were already planned, and it was that aircraft that was gonna take the extras. So, ops placed the aircraft on mandatory derate (except when wet). With extra load, some take offs wouldn't be legal on a derate, ops wanted to offload, the management wanted to keep the load, and yes, ssg, they said what you said... "it'll take a shorter runway, so if the engine quit, there's more stopping distance!"

Guess what? Not only that the management didn't want to off load... Halfway through the 16th flight out of the shop, the engine seized and the engine had to be sent to the shop. Engine repair costs? 300k USD! That's one extreme example of derate cost savings... *grin* (it was a CFM56-3)

But normally, if I was given the right numbers, the savings per flight on a 737-classics using derate t/o and climb whenever possible (with the company policy of not using stopway as ASD calculations), was about USD 50 per cycle, with all runways within the company's network being 2500m or less (except 5 airports, which had 3000m runways). The aircraft would normally do 8 - 10 cycles a day, so it'll save about 100 k- 150k USD a year by derating. That'll pay a few people's salaries over here.

We discovered that this experienced so called pilot was infact a 12 year old kid who was merrily googling his answers on the internet and somehow getting a kick by playing out his act. He fooled a lot of airline and corporate pilots for some time.
Well Pace, ssg could be on of them! LOL. I could be one of them, heck, any one of us could be a 12 yr old sim pilot with too much time on their hands.

Over here we got someone who went around with a fake crew tag, and convinced enough people he was a crew member with his talk, until he ran into a gate agent who knew the game and called security. If you wanna see someone leaving the terminal with such speed, you should have seen this guy!!!!

On the other hand, I've met a captain who thinks a 72kt wind aloft will break your plane apart and uses LDA against his TODR. I avoid paxing on his airline with good reason! But then, that fake guy I mentioned above uses this airline as his claimed employer... now why am I not surprised...

PK-KAR
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Old 21st May 2008, 17:12
  #105 (permalink)  
 
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I don't think you fly a plane
Oh cool, this sounds like you give me your ATP certificate number and I will give you mine......

Why is it that people must resolve to personal insults when they starting losing a technical discussion? Its most unbecoming!!!!!

Mutt
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Old 21st May 2008, 20:44
  #106 (permalink)  
 
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Trickle451...
1st 2 posts in this and the abort v1 topic... very interesting.

Trading safety for a buck, yes, and NO. It's not that simple as "it's safe" or "it's not safe". It's safe, relatively safe, comfortable risk, unacceptable risk.
The first two is what we're after. The last 2, don't belong in aviation.

No doubt in here he was fighting the rising tide of those that couldn't stand up to thier boss and say 'wait a minute...is this the safest it could be?'
The safest it could be is not to take the flight at all! To do the flight, there are risks, now, how much risks is acceptable? The regulations state what must be able to performed to an legally acceptable risk level.

That's how you take your shilling. If you want it the safest way, don't do the flight. Heck, even keeping the aircraft on the ground or in the hanggar has it's risks. There is no safest... only safer.

Mods/Admins... IP check please...

PK-KAR
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Old 21st May 2008, 20:45
  #107 (permalink)  
 
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No thanks...

Mr. Hoppy,

I don't have the statistical data to make the case for or against flex. I did just read however , that statisticaly, you have about the same chance of losing a tire as you do an engine..

If I was lining up on a 7000 ft field, I would much rather lose that tire on a 4000ft take off run then on 6000 ft take of run. More time to deal with it.

Longer runs, just like longer braking distances heat up the tires more. Also longer runs tend to pick up more goodies on the runway, such as parts from other planes, the result I am sure we can all sadly remember.
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Old 21st May 2008, 20:58
  #108 (permalink)  
 
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Mr. Hoppy,

I don't have the statistical data to make the case for or against flex. I did just read however , that statisticaly, you have about the same chance of losing a tire as you do an engine..

If I was lining up on a 7000 ft field, I would much rather lose that tire on a 4000ft take off run then on 6000 ft take of run. More time to deal with it.

Longer runs, just like longer braking distances heat up the tires more. Also longer runs tend to pick up more goodies on the runway, such as parts from other planes, the result I am sure we can all sadly remember.
exactly how do you:
a) Identify a tyre burst?
b) Calculate your new stopping distance?

You may also like to check out the manufacturers recommendations with regard to high speed stops!
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Old 21st May 2008, 21:36
  #109 (permalink)  
 
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Tire blow outs...

The last tire that blew on me, was in a landing actualy,.excessive nose down, veering to the right...took all opposite control forces to maintain directional control including directional thrust management, with extremely heavy braking. Had I been a little faster on at touchdown, the nose tire would have separated from the nose gear, and what turned out to be simply changing a tire, would have resulted in an incident at the very least. I was in a turboprop...had this been a jet, with less assymetrical thrust to counter the veering, and faster speeds, this would have been an accident, as I wouldn't be able to control the direction and the gear would have impacted, metal to pavement after the tire separated..

I am convinced that a blown tire on take off would create the following scenario

-1 Directional control issues
-2 Vibration (thumping)
-3 Excessive drag / Force impeding acceleration

Obviously if you identify this prior to V1, you stop. If you never identify it it you might not get off the ground at all. Post V1 the issue would be trying to accelerate past v1 to Vr. Same result.

Some of the latest accidents suggest the pilots kept chasing V1 or VR all the way down the runway, when they ran out of runway...some tried to pull the plane off at the end, others didn't...same result.

Base on personal experience I don't think identifying a blown tire is difficult, it's a violent experiece...just like in a car...the issue is trying to figure out with your new speed paradigm if you can make it to take off, or if you should stop...all your pre briefed V speeds just went out the door...
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Old 21st May 2008, 21:42
  #110 (permalink)  
 
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Obviously if you identify this prior to V1, you stop
Why is the recommendation from manufacturers not to abort high speed with a burst tyre. Of course if you believe the Spantax crash that killed 50 people was a resounding success then you might think it is a good idea!
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Old 21st May 2008, 22:09
  #111 (permalink)  
 
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Trickle,
read this then get back to us please!
http://www.faa.gov/other_visit/aviat...off_safety.pdf
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Old 21st May 2008, 22:40
  #112 (permalink)  
 
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If I was lining up on a 7000 ft field, I would much rather lose that tire on a 4000ft take off run then on 6000 ft take of run. More time to deal with it.

Longer runs, just like longer braking distances heat up the tires more. Also longer runs tend to pick up more goodies on the runway, such as parts from other planes, the result I am sure we can all sadly remember.
Anyways... now VERY ROUGHLY AND CRUDELY...
Say a 732... My TOFL 7000ft,TOEPR 2.15 SL, 30C... 54 tons, I'm carrying 50 tons... I can derate the T/O to 47C, and it'll give me EPR of 1.96... now here's a very simplified derate effect...
54 Tons V1Bal = 143kts, Stopping distance from 143kts = 2500ft.
at 50 tons I get V1Bal = 135. From 135kts, stopping distance = 2250ft and TOFL 6500ft

AccelgoV1 dist (54tons)= 4500ft
AccelgoV1 dist (50tons)= 4250ft no derate.

Now, I derate to 40C and presto, my AccelgoV1 dist = 4500ft... stopping dist from v1 is 2250... my ASD = 6750ft, I still got 250ft of margin.

My accelgov1 dist is the same if I'm at 54tons no derate or 50tons with AOAT40C.

Now, r u trying to tell me now that because I need longer distance, I should carry 50 tons with no derate instead of 50 tons with derate, for saving 250ft of runway?
OK, how about I just load up 5 extra tons of fuel, so I use up that 250ft of runway and putting my signature "added safety measure" on the dispatcher's copy just for the sake of "oh derate is dangerous?"

Sure, I'd rather stop with 2750ft left from 135kts instead of 2500ft left from 135kts. BUT, I'd prefer 2500ft left from 135kts than 2500ft left from 143kts.

And, given the engine reaction time to go to idle from the take off thrust from 2.15 EPR and 2.05EPR, let's just assume the worst, 0.2 secs... I'm only left with 200ft added margin left! (it trundle down at 250ft/sec-ish at that speed)...

Now U want me to add the $30-50 bucks worth of extra engine wear and fuel burnt for... say, 200ft of margin, while I have an adequate 250ft of extra margin in the beginning... so the price of the extra margin in the above scenario is $0.15 per ft by not derating. Now, does the cost of changing tires due to tireburst is equivalent to 15 cents a foot?

The aircraft will do 4000 hrs and 3500 cycles this year (assuming it flies for 350 days in a year, no other downtime including for overhauls).

By not derating, you're spending an extra $100k a year to reduce your tireburst risk which on an average year will cost a fraction of that.

While insurers love added safety margins, the extra margin (to lower the premium) is offset by the fact that it's not a cost saving, therefore can increase risk in other areas (such as financial, which then leads to other operational risks), including engine failure risk. Your insurance, might actually go up!

Now, you tell me, which costs more? changing a tire or shoving the engine into the repair shop? And remember, you've already spent that extra 100,000 USD... that's 2 captain's worth of pay where I am... all that for 250ft of margin above another 250ft I already have after derate? at 4.5 to 6 crew sets per aircraft, you can pay 1 whole crew set per year with that amount of money here (including cabin crew). By derating, the company can actually afford an extra crew set, which means, up to 20% less flying hours in a year, now, that means, you can do 80hrs a month instead of 100hrs (and then find short term crew when your annual limits are up), which lowers fatigue, which means safer operations! Fatigue is a higher risk than derating or not derating! Now, therefore, with this more valuable increase in safety through cost savings from the derate, the insurers will give you a lower insurance premium...

So, now, when you do have a tireburst or an engine failure at V1, your crew can handle it better and safer! Further reducing repair costs when these mishaps happen (you can't eliminate risk! If you want to, get another job!)

hey, guess what? MORE SAFETY AND COST SAVINGS THROUGH DERATING!

So, Ssg/trinkle/whatever your next username will be, still trying to say that derating is UNSAFE?

The last tire that blew on me, was in a landing actualy,.excessive nose down, veering to the right...took all opposite control forces to maintain directional control including directional thrust management, with extremely heavy braking. Had I been a little faster on at touchdown, the nose tire would have separated from the nose gear, and what turned out to be simply changing a tire, would have resulted in an incident at the very least. I was in a turboprop...had this been a jet, with less assymetrical thrust to counter the veering, and faster speeds, this would have been an accident, as I wouldn't be able to control the direction and the gear would have impacted, metal to pavement after the tire separated..
Now would you rather have a tired crew who flies 100hrs a month going through that or a fresher crew doing 80 a month going through that experience?

Now, does your plane have 4 or more main landing gear wheels?

If you never identify it it you might not get off the ground at all. Post V1 the issue would be trying to accelerate past v1 to Vr. Same result.
A 732 had a tireburst the other week, a friend of mine was on board. It was a few knots before V1, 7000ft runway. Guess what the crew did? GO... accelerated as normal, and it was a non event except for the notable vibrations for a few secs. Had time to prepare the tire change, prepare for whatever was to be expected on arrivals... Waaaaay better than stopping, with 1 less tire (discount the brakes on that wheel), possible directional difficulty on braking, etc, etc... and causing everyone to panic and may lead to pax trying to get out without crew instructions.

Base on personal experience I don't think identifying a blown tire is difficult, it's a violent experiece...just like in a car.
Had a double blowout on 1 side two months ago... shocker, but no big deal.

Why is the recommendation from manufacturers not to abort high speed with a burst tyre. Of course if you believe the Spantax crash that killed 50 people was a resounding success then you might think it is a good idea!
I guess Trinkle/Ssg never had an airline take off briefing... it'll cover what will make an abort between 80 and V1... on planes with 4 or more main landing gear wheel...

PK-KAR
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Old 21st May 2008, 23:22
  #113 (permalink)  
 
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PK-KAR

It is the fuel savings that launching in cold power, the thrust isn't needed, reduces stress on engines (just like derate, reduced power on airliners) and, esp, in older reheated fan engines, increased stall margins down the stroke. Ever see the video of an F-14 losing an engine just off the bow? It ain't pretty, level at best.

GF
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Old 22nd May 2008, 00:09
  #114 (permalink)  
 
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Can't argue with an early pre-V1 reject speed if a blown tire, but they state I have to get that actual number from my airplane manufacturer...do you know what it is in a Ferrari jet.?..would I have to dial up the underworld to talk to the designer long dead gone for 50 years?
No need. The takeoff data is already before you. You needn't contact the dead, just be able to read a simple performance chart and abide by the numbers.

If you don't have directional control issues, then don't risk a high speed reject...especially if you think you have a failed tire or wheel. If you do have directional control issues, then the matter is settled for you. Clearly you're not going anywhere if you can't maintain directional control.

Try to make this connection...loosing a tire on an 18 wheeler is a little different then losing a tire on a Yugo.
Try making this connection: people experience tire blowouts every day and don't lose control. A little vibration...yes. Pulling to one side; sometimes. Connect it further; lose that tire at the end of the road...gonna run off the road into obstacles when you can magically pull back and get airborne, and go back to the beginning of the road? Go fly.

The point is everyone on this forum doesn't drive a heavy...SOPS are different for each operation..
You're right. Many of us do both, or have experience in both...and yes, the procedures are basically the same. Specific aircraft procedures apply to each type, but competent professional training centers teach the same that airlines teach with respect to runway behavior and policies regarding stopping or going.

Then again, you've had ONE tire experience, and are now an expert.
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Old 22nd May 2008, 01:24
  #115 (permalink)  
 
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Good paper..
Good sarcasm...

Can't argue with an early pre-V1 reject speed if a blown tire, but they state I have to get that actual number from my airplane manufacturer...do you know what it is in a Ferrari jet.?..would I have to dial up the underworld to talk to the designer long dead gone for 50 years?
WHICH Ferrarijet? I've heard that term being used from the 732A to the 752 to the 345, down to the Lears and some of the Citations.

Assumptions that regardless if you saved lives and equipment, might still not have been a good decision, or that tire blowouts might not be felt, are assumptions from someone driving a desk.
The guys driving the desk are the guys paying your salary. They employ risk managers to convert operational risk to terms they understand, numbers. The guys fondling the yoke and throttles while trundling down the runway are the ones who make the business run, and the guys carrying the wrenches and test pens make sure the business keeps running, and the guys receiving the phone calls make sure those who want to pay to use the business actually gets on the plane and sits behind the guys fondling the yoke and throttles so that the desk drivers can get the money and pay the risk managers, the guys with the wrenches and test pens and, yes, the guys fondling the yokes and throttles again. It's all a chain and an appreciation of safety and risk management is needed for the business to run sustainably. Your (or your former self) previous posts reflect that you see it in boxes, you do what you do, and no one else understands what you do.

If the tire blow out isn't felt, no directional issues, and not keeping you from getting to VR, then it's a non issue at that point...it's not affecting performance...
But you say it does and did not mention it before. You put a blanket statement that a derated take off is less safe. It's not the case at least MOST of the time, and it's safe enough for most of the remaining time.

flies in the face of the Goma crash, were there was actualy a pilot to talk to who said 'after the tire blew, the plane wouldn't accelerate'
Goma? Hewa Bora DC9? Or another crash.
Anyway, this topic is about derates right? Any evidence that derate was used in that crash? The events of the crash is not that clear anyways, one source says the aircraft suffered an engine fire after 300m of take off run leading to an uncontained engine failure? Surely, at an airport of about 5000ft elevation, you think a DC-9-51 would have passed V1? I think NOT. The reversers were indicated to be deployed at the time of impact... now, did someone not do their PERF figures right that day? Or did they just decided to flaunt the Vspeeds and decide stop/go at a time they picked out of the blue?

Another source said the aircraft went through a puddle and resulted in loss of thrust in one engine. Another said tireburst. Air Safety Week mentioned BOTH tireburst AND engine failure.

It's a 6500ft-ish long runway but there are information that only 5250ft or 5900ft of it was usable.

Given the above and the poor state of the runway/airport, do you think they'd derate? If they did then I'm not surprised the airline is banned from going into the EU.

Or perhaps, since someone was adamant about aborting after V1... here's another danger...
They elected to take off to the South when the runway was wet, with standing water, while other aircraft were waiting for the runway to dry out. Nothing wrong with the TOW. They had about 50-80 pax, depending on who you listen to, and were apparently 4,000 lbs below performance limit.

The captain briefed, reducing V1 to 100 kts, with VR around 125, but didn’t change the speed card.

At 100 kts the F/O called “V1”

At about 125 kts, at the point of rotation No. 2 engine failed. (Or possibly barked with a compressor stall)

It was then that the captain elected to abort the take off.

They had so much speed that the airplane actually became airborne. When it slammed back onto the runway they took the nose gear off and subsequent braking with the main gear bouncing off the runway took some tires out.

They shot off the end of the runway at high speed, down the embankment into the residential and market complex. The airplane caught fire and came to rest by the mosque.

All of the crew, including all of the flight attendants managed to escape injury and the fire while most of the pax and people at the market were burned to death.

- Standing water on the runway MAY have caused the engine to stall or fail
- The Captain's decision to abort the takeoff at Vr instead of taking-off
No accident investigation report, so, no official information. Moot example. NEXT...

The issue here is not just reject speeds but if the plane isn't accelerating when you do say..ok..this isn't working I can't get to VR.
If that's the case, there's only 1 solution... STOP! STOP! STOP! PRAY!

Perhaps you don't have it in your manual...
"Aborting past V1 should only be considered if airborne flight is unattainable or that safe flight is practically impossible."

After V1, can't accelerate to Vr, is speed increasing? No? in most cases then, Abort. There is decision, and there is judgement. I'm sure you learnt ADP vs conventional in school...

So are you going to apply big jet SOPS to that that Cessna Twin or light jet you just bought?

The point is everyone on this forum doesn't drive a heavy...SOPS are different for each operation..
The point is to everyone in this forum, is, you love your lights and scream out loud the policies of the heavies are unsafe, and when proven what is not safe with your lights is safe with the heavies, you say they're two different things.

The rules and SOP I adhere to are in accordance to what I operate. Going on a C402, a burst tire and loosing control means I stop. If the burst tyre happen at a speed where the wing of the burst tyre can be lifted , I go. Lost the left tire once on t/o but wasn't me doing the take off, and we could lift the left wing up. If I get an engine failure, I know beforehand how much climb rate I'm gonna make. Still past V1, I go, unless I brief or have been briefed otherwise (depending on the circumstances of the airport... yes, bushflying keeps you on your toes just like the flying heavies). If I get engine failure and burst tyre at anytime prior to lift off, it's a stop. Took off from a gravel runway once and the props were getting hit and the leading edge was getting hit. We went... but if a tireburst and an engine failure happened between V1stop and Vr, we'd stop. We agreed beforehand that the tyreburst meant V1=Vr, but engine failure decision was v1stop.

Going on a twin airliner, as you said so yourself, different game. BUT, don't argue about being on a light saying the heavy is wrong and when shown it's safe on the heavy you run back and use the "but I was talking about lights" as an excuse. It's disgusting.

GF,
It is the fuel savings that launching in cold power, the thrust isn't needed, reduces stress on engines (just like derate, reduced power on airliners) and, esp, in older reheated fan engines, increased stall margins down the stroke. Ever see the video of an F-14 losing an engine just off the bow? It ain't pretty, level at best.
Never saw the F14 stumper... saw the single on the E4 stumper, and other types. I might have seen the Vigilante one... None of them were pretty! At least a tireburst on a sling, you can't do much except for have people watch sparks coming out of the contact.
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Old 22nd May 2008, 03:11
  #116 (permalink)  
 
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If your just about to hit V1, hear a thump, then a firelight, and the plane starts to decelerate...or the airspeed just stays there...hmmm...do you think you will get to VR?
Problem before V1...you're rejecting. Problem after V1, you're going.

Stick to one screen name. I realize that ssg got pounded and had no credibility, but coming back as a different name doesn't give you any more credibility when you're posting the same tripe over and over.

Clearly if the airplane can't fly then it can't fly. If you're talking a business jet, you're going to have enough power to accelerate to Vr from V1 with a blown tire. If you can't maintain directional control, then clearly you have to stop...that doesn't even dignify a discussion on the subject. However, you don't seem to have any significant real world experience if it always comes back to "in the simulator...".

If you had a tire or wheel failure approaching V1, was the problem you weren't accelerating because you were riding the brakes on the opposite side?
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Old 22nd May 2008, 05:50
  #117 (permalink)  
 
Join Date: Oct 2005
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- I have learned
So you say, but you didn't come here to learn, nor have you done so. You came here to preach a failed sermon based on conjecture, ignorance, and emotion, with no useful information. You certainly did not come here to learn.

Let's see what you've learned...

- I have come up to speed on Flex/Assumed (1 day?)wth Mutt / Pug running away from my questions...I gather they were your best. A nice way for corporate to save money, having the pilots fly 200 people a little closer to the end of runway...and possiblly thier last flight..
Mutt, a professional performance engineer with a major airline operating internationally, didn't run away from your questions, but provided you great detail and numbers, as well as asked you questions you couldn't answer. You haven't come up to speed on assumed temperature or flex, as you still seem to fail to grasp even the most basic aspects of either one. Whereas no safety margins are reduced or compromised, and whereas safety is enhanced on multiple levels with reduced thrust takeoffs, clearly you missed not only the boat but the wake it left behind. You appear lonesome and confused waiting on the darkened dock.

- I have learned that you boroscope your own engines instead of hourly limits, flying them to ridiculous times..visions of South West Congressional Hearings are floating by...
You haven't learned. Airlines work in concert with manufacturers and their respective airworthiness authorities in maintaining powerplants through full and complete maintenance programs. On-condition maintenance for some components, specific hard life time limited items for others. If an operator, with a full maintenance and repair facility cannot boroscope one's it's own engines, then who can?

Your words betray an absolute lack of maintenance experience. From my perspective of not only an ATP, but a mechanic and inspector with more than a few years of experience behind me, you have a great deal to learn, but refuse to be taught. Where honeywell or P&W or any other manufacturer may set time limited or cylce limited overhaul intervals on certain small engines used in light business turbojet aircraft, different standards are set for other powerplants such as are used on many airline-class aircraft.

Perhaps you take offense that the engine manufacturers set standards for the engines...but the engine manufacturers set the standards for the same engines you fly supposedly fly, too. You seem to feel that all engines should be maintained by the same time intervals as the powerplants with which you've come in contact during your extremely limited experience. You apparently haven't been educated on the fact that non-charter, non-airline engines are often maintained on an on-condition basis, and many charter and airline departments have authorizations based on very close observation and documentation to significantly extend overhaul intervals, too. I've worked for several such organizations myself; companies which had such advanced experience with the particular powerplant that the manufacturer and the FAA provided authorization to extend the life of the engine by significant numbers.

Powerplants on test cells have run nonstop for years, over a decade, with little more than fuel and oil provided...including some of the same powerplants you have theoretically flown. Imagine that...did you know that?

You've learned nothing, but continue to run your mouth (or keyboard as the case may be). Why don't you tell us about these "South West congressional hearings." What hearings might those be? Are you familiar in the least, beyond a mindless google search, of the circumstances surrounding the media circus regarding Southwest Airlines? Clearly not. You might try educating yourself. No one else can.

- I have learned that airline pilot logic is that if we put less power through our engines, but take away all available runway stopping margins, the flight is safer
Powerplants run at reduced temperatures and power settings last longer, are safer, more reliable, and more dependable. Reduced power takeoffs are according to data provided by the manufacturer, under manufacturer approval, and fully approved by the overseeing aviation authorities (such as the FAA, CAA, etc), and meet every single safety margin there is. There is no loss of stopping ability or distance, when the takeoff is calculated to be stoppable from V1. The point on the runway varies with the power setting, but the required runway is always available. You've learned nothing about "airline pilot logic," which is actually aircraft and powerplant manufacturer logic, Federal Aviation Administration logic, Airline logic, Flight Safety International logic, CAE Simuflite logic, corporate logic, NBAA logic, etc. Seems you're the lone turnip out there that can't comprehend it. Safety is never compromised when calculations are done properly.

- I have learned that airline pilots, after about a 1000 posts will eventualy cave that it's possible a plane won't fly after V1, but that is a dark, dark prospect to an airline pilot who has built his balanced field into the stopway, is probably running overgross....and is told he HAS to go after V1...it's like you have to admit your religion is false..
We have learned that you've repeatedly attempted to introduce popular media articles regarding overruns or entirely irrelevant fly-by's in an effort to discuss this topic, but that you've ignored all the data provided by performance experts, using the factory numbers which show you and your ideas to be wrong and a lie.

You've failed to grasp the fact that the field doesn't need to be balanced, is seldom balanced, and has no reason to be balanced...and when it is, it's often by coincidence. Yet you keep coming back to it like a student pilot to his beginner's textbook.

You've claimed ten thousand hours of flying you don't have, and perhaps the only truthful statement you've made is that you've been rejected by an airline...for which you seem to have nothing but a case of sour grapes. You need to bear in mind that your own failures and your own inadequacies are not the fault of others here, but yours alone. You've claimed to have been trained at FSI...but FSI doesn't teach stopping after V1; you either didn't go, or lied about the training you received, but we've learned that no matter what name you choose to log in under, you still lie. No credibility.

- I have learned about V speeds ad nauseum, and thanks to those that linked all sorts of advisory circulars and educational .pdfs Those links and my ability to sort the info gave me enough bullets to take on all comers, and if I might ad, fight off guys that supposedly do this for a living.
If you count making yourself a laughing stock among some very respected professionals who really see you for what you are, then you've done well. Otherwise, thus far all you've managed to do is continuously lose credibility every step of the way. You still seem to fail to grasp the concept of V1; you've learned nothing.

- I have learned that 'taking the shilling' and 'doing what the SOPS say is basicaly a subsitute for safety..and very few in here are able to stand up to the social will of the group or the need to sit in a plane.
If by "taking the shilling" you mean that pilots are willing to compromise safety for pay, you haven't a clue. Where no lack of go distance, stop distance, and obstacle clearance exists due to very advanced and detailed calculations for every takeoff and every landing (when was the last time YOU performed a runway analysis or determined your obstacle clearance criteria with an engine failed on the go...or that you actually flew something other than a laptop computer??)...safety isn't compromised. As a professional aviator, I'm first to the seen of the crash, standing at the head of the line in front of anyone riding in back. I don't compromise safety; not by using reduced thrust, not by continuing after V1...every aspect of what I do is fully backed up by the performance capabilities of the airplane and methods and practices that aren't just written in ink, but in blood. That includes the knowledge that stopping is far less safe than going.

"Taking the shilling" means exercising the judgment to complete the flight safely, and that' what we're paid to do. Exercise the judgement to be safe. Reduced thrust takeoffs are safe.

My Operations Manual spells out all the conditions under which I can and can't make the flight. One overriding statement nullifies any issues regarding reduced thrust and that is that the PIC ALWAYS has the authority and discretion to make a full thrust takeoff if he desires. The truth is that it's often unnecessary, for many reasons that have been hereto discussed, with NO compromise to safety.

You've learned nothing.

- No one has standed out...maybe a comment here or there, to help..but no warriors or heros. I know you tried, thanks...but you caved to social pressure.
Standed out?

- At the end of the day..no one stated what was best for the passengers, but only what was good for saving a buck.
Reduced thrust takeoffs are best for the passengers. Reduced thrust increases safety margins on many levels, from reduction of minimum control speeds, to more reliable, safer engine operation over extended periods, fewer failures, extended mean time between failures, and ultimately, even the financial needs of the passenger are attended with reduced costs. Safety is always the chief concern, and reduced thrust caters to safety first and foremost. Clearly you have learned nothing.

Maybe one of these days I will see you in a sim or be called to consult at your company, I suggest you keep your opinions behind the veil of internet privacy...in the a room full of pilots, books, pen and paper, they would be hard to justify, and might cost you your job. I have no quams going toe to toe with people in an area of my expertise. If I had been schooled here, I would have admitted. I did learn some things, important things, but also saddened by the lack of horse sense, morality, and decision making skills that should be ineherent in a person that flies proffesionaly for a living. My goal was not to gauge, but be educated, and I was.
No, your goal wasn't to be educated. You won't be seen in any sim I'm flying, and I don't play with microsoft sim, so chances are slim that you'll see me...or most of the other people here. There is no chance you'll ever be called to consult at any company where I fly. You see, I've done the kind of the flying you've done, a great deal of it, plus more, and know the type of training you should have received...but you fly in the face of all of it. I've seen your kind washed out of training programs at Simuflite and FSI. I've known more than a few of your kind who are dead now due to your need to operate by your own understanding. There's always someone who thinks they can reinvent the wheel, and you're that someone. The shame of it is that you don't appear to have a clue just how many folks are laughing at you right now.

You go right on believing whatever you want to believe. You will, anyway. One can only hope that you aren't flying an actual aircraft, or that if you are you quit soon, lest someone innocent die at your expense.

Time to put your latest alter-ego on the ignore list.
SNS3Guppy is offline  
Old 22nd May 2008, 06:17
  #118 (permalink)  
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Likewise, this has been a spirited thread.

Procedural points to keep in mind ..

(a) several folk have complained about some of ssg's posts. Be aware that I am following along behind and I alter/delete posts which I think are a bit out of line .. not just ssg's .. any ...

(b) so long as the posts are not too far out of order and the subject remains reasonably on flying matters the thread can remain here to stir up objective passions

(c) if individuals get to the stage where they feel that the thread is going in circles or whatever, there always remains the option to ignore it .. when enough lose interest it will, like near all threads ... sink into the abyss.

As a moderator, it is not my personal task to be the arbiter of what content should or should not be in threads .. only that they reasonably follow PPRuNe requirements.

The only "rule" we have here is that outright rudeness etc., will be modified or deleted as we consider appropriate


Now that I have finally caught up with the leading edge of this thread .. it is evident that ssg/trickle451 is now pursuing an unuseful path .. one of my colleagues has beat me to the punch and given the poster some time out. As you all would be aware, we have a great tolerance in this forum .. but, occasionally, the odd individual does take too great a liberty with that tolerance.
john_tullamarine is offline  
Old 22nd May 2008, 13:25
  #119 (permalink)  
 
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Although ssg has many of us pushed to the point of exasperation, I've felt this thread was useful if only to expose us all to the fringe element, to try to understand their motivation. Operational economics was certainly not his motivation.

And even more revealing were the issues ssg nicely sidestepped.

PS Thank you JT for bringing a new word into my vocabulary - unuseful
barit1 is offline  
Old 22nd May 2008, 18:19
  #120 (permalink)  
 
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There are thousands of engines operating on the wing after considerably more than 60.000 hours. I have no idea what the longest lived engine is before its first shop visit but I am sure it is well in excess of this figure.
I have experience of a CFM 56 in Germany that has been on the wing over 70.000 hours.
I have heard of RRs on B757 that are also well in excess of this number.
I am only guessing, as would you be, but if every take off were made at Max Thrust, I suspect these numbers would be considerably lower.
The answer to the question originally posed, so eloquently and thoroughly answered here, is yes.
rubik101 is offline  

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