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Pilot Incap at 80/100 - what to do?

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Pilot Incap at 80/100 - what to do?

Old 15th May 2008, 20:47
  #41 (permalink)  

ECON cruise, LR cruise...
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...thought we were on the subject of an abort well below V1... or is poor old Empty missing something here???

No-one seems to disagree on what kind of % runway length should be consumed to reach V1 and Vr respectively. And yes, with de-rate & everything, we normally rotate within the first 65% of TODA on a runway limited departure.

The q still is - do people think it's wise to stop or to go when the incap has been confirmed at V1-30?
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Old 15th May 2008, 20:50
  #42 (permalink)  
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Thanks Empty!!!

Ah the voice of reason.....
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Old 15th May 2008, 21:48
  #43 (permalink)  
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So if your at V1 and burned up 85% of the runway, you see that as a problem right?
Yes .

So when I see an airliner burning up 90% of the runway to get to VR. I know he didn't have the right numbers.

These are 2 very different things. Have you ever flown a heavy? I see your profile shows you're on the G-IV. Twins usually get airborne earlier than the tri/quad engine aircraft but not always. Look it up!

As for the stop/go - every time is different with too many variables to list, but here are some (in no particular order):-
Day/Night, Dry/Wet/Contaminated, Calm/X-wind, Alert/Tired, Circadian time, Experince total, Time on type, Training, Company policy, SOP, Area weather (CB's), Local terrain, Area familiarity, Control restriction/obstruction, 2 crew/Flt Engineer or augmented, Shock etc, etc.
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Old 15th May 2008, 22:33
  #44 (permalink)  
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A pilot that just throws the levers forward and waits for V1 and VR without looking outside to see how much runway he's burning up in the process should be serving tacos somewhere...
PF's looking out, PM's looking in.

What if your flaps are set wrong, pitot tube blockage, flat tire on take off, engine doesn't produce enough thrust, TR deployment, Spoilers accidentaly deployed...whatever...all will increase runway distance....so if your just looking at your AS indicator with a flat tire, waiting for V1, not looking outside...your gonna crash....
PF's looking out, PM's looking in.

Flaps? Config warning sounds and why there's a pre-takeoff checklist. Blockage? One reason for the airspeed callout on TO. Not enough thrust? PM will notice. TR/spoilers? PM notices, config warning sounds. Tyre burst? Actions covered in the takeoff brief.

So when I see an airliner burning up 90% of the runway to get to VR. I know he didn't have the right numbers.
You can't know the numbers were bad. The situation you describe is perfectly possible. In these cases, V1 will be less than Vr.

The fact is...737...if your not looking outside to see how much runway your burning up to get a read on whether the plane is performing, that you are in the right place at the right time....I honestly doubt you will catch you capt between V1 and VR having a silent stroke....this thread is moot for you...
Someone is looking outside and both pilots are monitoring performance.

Am I the only one in here that undestands the 60/40 rule and what it means?
Haven't come across that. Or if I have, it's by a different name.


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Old 15th May 2008, 22:55
  #45 (permalink)  
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I think that we could be a little more reserved in the discussion, folks ... no need to get hot under the collar ..
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Old 15th May 2008, 23:26
  #46 (permalink)  
st nicholas
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Above 80 knots and prior to V1, the takeoff should be rejected for any of the
• fire or fire warning
• engine failure
• predictive windshear warning
• if the airplane is unsafe or unable to fly.

from 737 QRH.

controls free and safe -continue if not and before V1 -stop

Old 15th May 2008, 23:51
  #47 (permalink)  
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It's just a discusion...no worries..

You got me Helen....I don't fly for the airlines....Dual Rated, 10,600 hours and 7 type ratings wasn't enough to convince the chief pilot of Alaska Airlines,(two months ago) that I could be an airline pilot....I remember him asking me this right off..

'Why now?' and the HR lady saying....'What would you do if you were offered a better job?....that's how the interview went for about an hour....

But hey I guess the good news is...they liked my resume, the line pilots interview went good, the hotel was nice, and I passed all the psyche quizes....

Sorry for the thread creep...but I think what posters in here are trying to convince me of is this very simple concept.

Airliners burn up 65-75% of the runway to get to V1, and it might take another 3-4000ft to accelerate to VR with a thousand ft to go...

So be it...but honestly guys, accelerating another 3000+ ft trying to get to VR(were going no matter what!!!), with the fence coming up, knowing that I could suck a bird, blow a tire, and just not make it, doesn't seem like a safe way to spend the next 30 years of my life....

Call me silly....

Last edited by ssg; 16th May 2008 at 00:03.
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Old 16th May 2008, 07:56
  #48 (permalink)  
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Trying to find another way to put it...

With the correct numbers, if you call stop before the V1 call you will definitely stop.

If you call continue after V1 and you ingest a pheasant into number four, as long as the FADECS or you ensure that flex thrust goes to max, you'll make it.

Keep using the correct figures, and all 30 years on a heavy will be safe.
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Old 16th May 2008, 08:31
  #49 (permalink)  
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If you useing assumed temp/flex you do not need to go to full power to mack it. You may well feel its a good move and I wouldn't disagree but the numbers assume you leave the thrust levers were they are.

If you've used a fixed derate (ie go into the FMC and derate the engines from 22k to 20k of thrust) and then flex on top of that then I think you can run into snags with VMCG if you go to max chat. I'm not 100% on that as we don't do it but dim and distant and all that.

While the discussion started off around the 80kt call there is no reason why the Capt might not fall over with a heart rending plea for help just prior to V1 so its as well to think about the high speed case too.
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Old 16th May 2008, 09:13
  #50 (permalink)  
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Nothing wrong with not being in the bigger iron, sorry it didn't work out for you so far (keep trying?).

could suck a bird, blow a tire, and just not make it, doesn't seem like a safe way to spend the next 30 years of my life....
Life is risk management. A tire or a bird by themselves shouldn't cause the carnage you seem to worry about.

Back to the thread..........
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Old 16th May 2008, 10:12
  #51 (permalink)  
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If you have pilot incapacitation high speed rejects should not pose a problem because you're not going high speed. 80kts is a first check. If there is no response, you are in your mind already stop minded. If he doesn't answer your second inquiry (100kts ie), you stop. In most aircraft you are even below Vmc at this point. 1...2 seconds reaction time gives an extra 7-8kts acceleration. Let's say 110kts max at the point of reject. On the 737 Vmc is around 110kts. This means you're at the edge of its "controlled flight" envelope, and since you were stop-minded from the very first 80kts call, in most cases you will not even be at 110 upon initiation of the reject. Stopping at this point should not pose any problem at all. You are FAR FAR away from a high speed reject which, I agree, isn't the most fun thing to do with an airliner.

At high speeds it's designed to fly, you are go minded, at low speeds it cannot even control it on the runway if you were to continue and have an engine failure. There is indeed the "grey" area in between low and high speeds, but that's why the 80kts check IS a pilot incapacitation check as well, to PREVENT you go into the grey zone. So simply be ready for it.

SSG, V-speeds are not all based on runway numbers. Vr and V2 are weight based and because V1 cannot be greater than Vr, it is in a lot of cases weight based as well. It's not because you have a balanced takeoff performance, you're using all the runway available. It fits "into" the runway, yes, but you'll have extra room. If the runway in it's current state doesn't fit, you need to change something (bleeds off, higher flap setting, another runway for better wind conditions or longer length,...). V1 is something you can play around with, and runway length can be a factor.

There are some exceptions, ie improved takeoff where you use as much runway as possible (keeping in mind tire limits etc) to have a better climb performance when you are ie obstacle limited. It's the only case where I don't like the V1 numbers (sometimes very high on long runways), but I trust a very high speed reject can be done. With all the consequences: hot melting tires, probably a fire, maybe you block the runway, maybe you end up in the grass because life is not perfect (or the water). I've talked to people who have rejected takeoffs, and they all say: "the braking is hell, nothing you've ever experienced before". And RTO tests were performed with degraded brakes during testing, so in the end I presume it will work although some V1 values don't really give me a comfortable feeling.

Wet or contaminated runways? Well, V1 is reduced as well, and on contaminated runways pretty much based on Vmc. Things can be tricky because controllability is an issue for every speed. But 100kts is still a reject because it's below Vmc. You really need to be prepared for it in these cases.


Ps: the 60/40 rule is a guideline for small single engine props where you simply have no decisions speeds. If you encounter a problem before using 60% of the runway, stop. Don't try to stop a little prop on less than 40% of the runway available. Funny someone claims a "PPL-we-have-no-rule-for-it-so-use-this-guideline" to be used on commercial jets as a governing rule...

ps2: heavies are usually runway or even "braking" limited, but the story remains the same: pilot incapacitation and high speed rejects should not come together. Either you reject low speed, or next calls are V1 and Vr, and it's a go anyway if he doesn't respond.

Last edited by BraceBrace; 16th May 2008 at 10:29.
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Old 16th May 2008, 11:05
  #52 (permalink)  
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Thought about this last night, I was flying out and the Capt back. I fly a 738. So we get to 80kts, he calls, our SOP's require I look inside call 'Cross Checked' then back to the action, still below 90kts, even with a light load. If there is no response pnf has time to call 100kts, and still has time to reject quite safely. no drama, same on the return leg, fully loaded, no problems stopping if needed.
As to using up 75% of the runway, sorry not sure where that comes from, we don't.
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Old 17th May 2008, 05:46
  #53 (permalink)  
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Brace - Its all about putting the plane in the particular place on runway, at a particular speed...to either stop, or go...

If you find yourself at 75% of the runway, still chasing V1...remember this thread...

Something to read...


LEXINGTON, Kentucky (CNN) -- Why would an experienced pilot take off on a runway too short to accommodate his commercial jet -- rather than the longer one he told air traffic controllers he planned to use?

That's one of the questions federal investigators are trying to answer Monday as they dig into the data on Comair Flight 5191, which crashed Sunday morning about half a mile past the end of a runway at the Lexington airport, killing 49 of the 50 people onboard.

The Delta Air Lines commuter flight to Atlanta, Georgia, had been cleared to take off from the 7,000-foot Runway 22 at Lexington's Blue Grass Airport, said Debbie Hersman, a member of the National Transportation Safety Board. (Watch the NTSB describe the evidence found -- 1:27)

Based on the cockpit voice recorder and tapes from the control tower, "there were planning discussions, both by the air traffic controllers and the crew, conversations with each other, about using Runway 22 for departure," Hersman told CNN on Monday.

"We do know from the information that we have obtained on scene, gathered evidence, documentation and from the flight data recorder, that the runway that the crew used was Runway 26," which is about half as long as Runway 22.

Hersman would not say whether the Canadian-built Bombardier CRJ-100 would have been able to take off successfully from a 3,500-foot runway. (Watch the results of an early NTSB review -- 3:27)

But former NTSB Vice Chairman Bob Francis said that the twin-engine jet would have needed about 5,000 feet of runway for a successful takeoff.

"It sounds like it got barely airborne and came back down, but there isn't really enough evidence yet to draw that conclusion," Francis said. "I can speculate; they cannot."

The Associated Press reported that the short runway had less lighting than the one the plane should have used, and severely cracked concrete -- not the type of surface typically found on runways for commercial routes.

Hersman said the NTSB probe will look at recent construction work at the Lexington airport, the lighting and the markings on the taxiways and runways.

Investigators also will study what went on in the tower, how many controllers were on duty and whether they saw Flight 5191 head down the wrong runway.

It's rare for a plane to get on the wrong runway, but "sometimes with the intersecting runways, pilots go down the wrong one," St. Louis University aerospace professor emeritus Paul Czysz told the AP.

The sole survivor of the crash, first officer James Polehinke, was in critical condition at a Lexington hospital, and was not able to be interviewed at this point, Hersman said.

The plane was carrying 47 passengers and three crew members. One of the passengers was an off-duty crew member sitting in the plane's jump seat, Blue Grass Airport Director Michael Gobb said. (Honeymooners among victims)


Enough Said.....
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Old 17th May 2008, 06:31
  #54 (permalink)  
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Pilot Incapacitation.

The original question. What will the F/O do if he gets no response to an 80 Kt and 100 Kt call when he is the PNF. Seems pretty darn simple to me, regardless of what the company SOP says regarding who can call for an ABORT. Any Company which dictates that only the Captain may command an ABORT and that he must conduct the ABORT, would surely do so on the assumption that the Captain is not incapacitated. What any F/O should be aware of is that his/her backside is as precious as any other on the aircraft and if he/she determines that the handling pilot has become incapacitated then he/she has no option but to assume command. That is why there are two pilots, each qualified to fly the aircraft. All the rest of the myriad of postings are academic. Obviously, if the handling pilot becomes incapacitated well below V1, as I would believe the original question indicates, the F/O should ABORT. If above V1, GO. Any pilot who thinks otherwise should think seriously about another career path.
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Old 17th May 2008, 07:17
  #55 (permalink)  
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Even if you want to go into this case, you don't know the reason why they used that runway, or what they saw and experienced, when they realised something was wrong.

737, between 80 and V1, you only stop for any fire or smoke, engine failure, predictive windshear or aircraft unable to fly. Here you have to consider the last item, this would depend on your speed primarily as stated before. Low speed it's better to stop, high speed you better continue. If I were to be at 85%, not knowing if I'm going to make it but in the high speed region, I would still continue (firewall the engines if necessary). Because this would be an indication my performance calculations were wrong, making my V1 doubtfull as well. If I'm high speed, I should be pretty close to the flying envelope. And probably far away from the required stopping distance as well. If I would be around 80-100kts, yes I would stop. Both cases will take some sweat though... but I don't see why you should doubt current airline procedures.

There are plenty of other situations where you need to decide quickly and most airlines train the pilots to slowly become go-minded above 80kts, and the higher the speed, the more go-minded you should be. All because the airplane will fly even at speeds slightly lower than Vr/V2, and is hard to stop. This training does not rule out the stop option at low speeds. A nice example is the pilot incapacitation check at 80kts (to stay on-topic).

In the past there were a lot more RTO's that went wrong, than cases like the one you mentioned. Don't make the past come back please.

Last edited by BraceBrace; 17th May 2008 at 07:29.
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Old 17th May 2008, 08:42
  #56 (permalink)  
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SSG, because I'm polite I won't say what every is thinking about you. What if they used the wrong runway? What if they input the BS figures you're so keen on? What if they burst a tire, lack of thrust, etc etc?

Here in the professional world, we work with the facts. Not making stuff up and then just crossing our fingers hoping it all works out - which seems to resemble a take-off roll on your G4.
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Old 17th May 2008, 09:50
  #57 (permalink)  
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So if no communication, challenge and response by 100kts:

In A340-600 at 380 tons, the F/O will take control and stop by 100kts. The problem getting airborne and flying it around again and dumping 115 tons. MLW 265 tons The complications gather at a rapid rate of knots once airborne and even then, the incapacitated pilots needs urgent medical attention.

However, at 380 tons, there would be a double crew (leg distance is ULR), but the other captain from crew B, sitting in first observers seat, (an Airbus term) is not at the controls and I am sure he would also tell the F/O to stop by 100 kts. Autobrake is working so don't touch the brake, unless autobrake is not working. Reverse thrust is not considered for rejected take-off anyway, incase the engine had failed and was the reason for the rejection. The F/O is welcome to use what he needs and what he has at his diposal, but thrust reducton is a must, in line with directional control.

The rest will be history and remember "PARK BRAKE SET", otherwise nothing like doing 15 kts in cirlces while you're trying to pay attention to other things in the cockpit. Work load has to be at it's highest form on this one, for a single crew.
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Old 17th May 2008, 10:58
  #58 (permalink)  
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I think overall it best in any aeroplane to stop in that situation at that sort of speed.

It is, of course, possible SSG does not ACTUALLY fly, let alone fly a GIV, and even if he/she does, then presumably has never been onto a short strip where less than 1000' to go is not unusual with the nosewheel still on the ground.
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Old 17th May 2008, 13:20
  #59 (permalink)  
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what´s so hard about this scenario...
u call 80 kts..or let´s say 100..no reply....call it out loud...100 kts still no response? grab the throttles before those already 115 kts become 135. bring them back and then continue the takeoff rejection depending on the a/c u fly...is there any doubt about this?
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Old 17th May 2008, 15:26
  #60 (permalink)  
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We routinely see red lights at the end of the runway on takeoff. Late in the takeoff, I'm not sure that I want to be attempting to get stopped while looking at the red lights. whatever lays beyond them isn't in my favor, though returning to land with the full runway ahead of me certainly is.

Can I fly it around and get it landed by myself? Without question. There's no question I'd much rather do that, than attempt to do a high speed rejected takeoff.

The original question involves an incapacitation at 80 or 100 knots. We generally brief such that any problem up to 80 knots merits the rejected takeoff. After that, it's controllability issues or clear safety of flight issues; the other pilot incapacitated isn't one we brief, or one I'd consider necessarily significant enough to perform a high speed reject. Does the other pilot being unavailable preclude the airplane getting into the air or affect directional control? No. We're probably going flying.

When asking if the takeoff should be rejected at that point for an incapacitated pilot, one may be asking the wrong question. Perhaps a better question is who is going to take the airplane into the air. If the other pilot is truly incapacitated, then clearly the takeoff (and subsequent return for landing) will be performed by the one who isn't incapacitated. However, if it's a matter of a full-functioning pilot who didn't hear the challenge, or wasn't heard (I've had ICS failure at that inopportune time...we were both talking, yelling even, but couldn't hear each other over the increadibly loud radial engines)...book says if no response the second time, take control. Nobody was incapacitated. Just deaf.

High speed rejected takeoffs present a multitude of hazards, often far less than continuing the takeoff.

Simply because the performance data says the airplane can be stopped aproaching V1 doesn't mean that one should without just cause; an aircraft under control and accelerating properly is not necessarily just cause to reject the takeoff.
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