FA Calls on short final..

Everybody seems to be overlooking the fact that there is more than one reason to abort a takeoff. Catastrophic engine failure is, in my opinion, the easiest scenario when it comes to aborting. It really doesn't take any decision making as you will know what is going on. It is also directly addressed in the definition of V1, "minimum speed in the takeoff, following a failure of the critical engine at VEF , at which the pilot can continue the takeoff and achieve the required height above the takeoff surface within the takeoff distance." Because of this definition, we all associate V1 with engine failure and we know how we would react. Engine fails before V1 and we stop, after and we abort. Easy! Well, easy in discussion.

There are also a handful of other reasons that may require you to stop. The decision to abort for these other reasons may not be as cut and dry and it is that decision making process that was taken in to account while deciding to call V1 at V1-5 knots. I didn't come up with that policy, but as a pilot at that particular company, I did agree with it. That company operated a plane that was very overpowered. Acceleration was insanely quick.

Let's say at a few knots before V1, there is suddenly a flashing light in your face. Do you abort? I would assume that many people reading this would say "I have no idea." Why? Because the light alone doesn't tell you much other than something out of the normal is going. So now you have to look down (or listen for PNF). So you look down and read the message. Your brain then has to comprehend what that little bit of information actually means and you have to react to it. Let's say that you make the decision to abort. How far above V1 do you think you are after that little scenario played out? I'd be willing to bet that you are at least a few knots above by the time you pull power or apply brakes.

My point is that, this isn't as cut and dry as some people would like to think. Every takeoff is different and things like weight, runway length, what is past the runway, etc should all come in to play every time you line up.

Can't speak to jets, but in a turbo-prop with functioning reverse, a dual engine abort up to v1 is almost a known event on a good runway. If it's contaminated, that's a different story, but not one that's really germane to this discussion. What I can say is that this is why your hand should come off of the throttles at V1 as PF in any kind of operation I've encountered. In the 1900 my right hand would come off of the throttle at V1 and calmly come over to the yoke where I would gently rotate with both hands on the yoke - after positive rate, I then reach down for the gear and we're off flying. But my recommendation would be for you to build into your mind what you're going to do at any given time, and then operate that way. You can abort up to V1 and meet the applicable performance data, but unless you know the airplane "cannot" (as in wing falls off) fly, you don't do anything after V1. If you get the firebell at V1 -1 and you don't instantly springload into action (and who would, we're all human) don't try to abort after V1. I guess maybe the way to say this is that if you're going to abort, cross-reference your speed prior to aborting, because the consequences for a highspeed abort can be dire. Further, you're probably already monitoring your IAS on the takeoff roll anyway, so use that information appropriately.
 
The lav is a locked box with four walls. You could probably do a barrel roll and the person inside would come out OK. I think you'll be fine.
 
FAs are trained not to bother the front during sterile unless its an emergency. They even go over the types of emergencies that warrant a call up front during sterile and most involve smoke, fire or parts falling off the airplane. A pax in the lav on final is more of a minor inconvenience then a real emergency. Its possible that the pax may be having a medical emergency in the lav so landing right away would be the best option. Man, there are some whack ass stories of FAs calling the cockpit during sterile. One I heard at XJT was an FA calling the front at minimums to ask the captain (female captain) if she had any tampons she could spare.
 
FAs are trained not to bother the front during sterile unless its an emergency. They even go over the types of emergencies that warrant a call up front during sterile and most involve smoke, fire or parts falling off the airplane. A pax in the lav on final is more of a minor inconvenience then a real emergency. Its possible that the pax may be having a medical emergency in the lav so landing right away would be the best option. Man, there are some whack ass stories of FAs calling the cockpit during sterile. One I heard at XJT was an FA calling the front at minimums to ask the captain (female captain) if she had any tampons she could spare.
Wow...
 
You know, the more I think about it the more I disagree with calling V1 5 knots early. While it might be advantageous for an aborted take-off situation, I'm not sure I'd want to be the guy test flying an airplane where we decide to continue the take-off when an engine fails PRIOR to Vef (see definition above).
I think I finally have an answer for why we call V1 in the Dash before Vr on a 10000 foot runway. Thanks Steve.
 
Well often times in the the Q200 our v1 speed will be in the mid 80's range while rotation isn't until the upper 90's. I never knew that V1 meant anything other than the speed at which you could abort before and be able to bring the aircraft to a stop safely before the end of the runway. Apparently so did everyone in the training department I have asked. My biggest question with it was because you can clearly bring a Dash to a stop on almost any runway over 5000 feet even if you were at rotation speed. And I knew that the ERJ's I commute back and forth from work on usualy have V1 and VR as the same speed when departing EWR so I always questioned why ours was so slow. I had no idea there was more to V1 than that and Steve pasted the actual definitions up. I guess by the definition of being able to fly after V1, having a lower V1 is actually a good thing in an aircraft like the dash.

Just pointing out that I had no idea, and Steve shed some light on a question I have had for quite some time.
 
Well often times in the the Q200 our v1 speed will be in the mid 80's range while rotation isn't until the upper 90's. I never knew that V1 meant anything other than the speed at which you could abort before and be able to bring the aircraft to a stop safely before the end of the runway. Apparently so did everyone in the training department I have asked. My biggest question with it was because you can clearly bring a Dash to a stop on almost any runway over 5000 feet even if you were at rotation speed. And I knew that the ERJ's I commute back and forth from work on usualy have V1 and VR as the same speed when departing EWR so I always questioned why ours was so slow. I had no idea there was more to V1 than that and Steve pasted the actual definitions up. I guess by the definition of being able to fly after V1, having a lower V1 is actually a good thing in an aircraft like the dash.

Just pointing out that I had no idea, and Steve shed some light on a question I have had for quite some time.

Good deal. I was just curious to hear an expanded thought process of what you were talking about or thinking. Good stuff.
 
Yeah man. Always looking for more. My problem is that in many cases I don't know where to look. I learn a lot from conversations like this one. Not so much the abort for a chime or go around for a chime deal, but the V1 convo was a goodie!
 
I suppose I'm a little bit leery of v1-The-Idea, myself. The Rules aren't set up to accept a minor accident as a possibility, but I'm sure as hell prepared to accept a minor accident, loss of license, and loss of career to avoid becoming a scattering of parts in a flaming hole. Every page of your performance data was written using a brand new airplane with near zero timed engines and a couple of test pilots who knew what was going to happen. And yes, sure, there's some "fudge factor" built in, but it's hard to calculate that when the engine quits at v1+5 on that last leg and your head is already at home drinking a cold one. Certainly it's a useful guideline.

PS. Just kidding, FAA, I obviously fly the aircraft in strict accordance with the POH. I was just testing these youngsters for any vestiges of free-thinking.
 
I never knew that V1 meant anything other than the speed at which you could abort before and be able to bring the aircraft to a stop safely before the end of the runway.

I also had this misconception. Thanks again to JC for increasing my knowledge. Neat how this thread has turned into a virtual fount of knowledge. Nice going, fellas! :)
 
This is why our company policy is to brief that we will abort for any abnormality up to V1. We don't try to differentiate between what flashing lights mean what while accelerating down the runway, we keep it simple. Anything wrong, abort. (Remember that we are in small corporate jets, typically operating on runways with PLENTY of room to stop in case of a high speed abort. We stress to our captains that they retain the PIC authority to modify the abort criteria if the runway is *short*, and in those cases many will choose to add the "after 80 knots we'll abort only for engine failure, fire, loss of directional control" or similar kind of caveats. I'm sure airliners are a different kettle of fish entirely.)

Agree. Esp when it comes to a runway with plenty of distance to use. That way, you're not aborting for something that turns out to be a pitot heat warning light (or something akin) and end up blowing tires during the abort, to use an extreme example.

On the flip side, there are times Id abort past V1 if need be. To me, its not as simple as "past V1 Im flying, regardless of whats going on"; because that can potentially get you killed, depending on the emergency, as easily as an abort past V1 can. But sometimes, those are the breaks of the game, and life isn't fair. I'd rather be a little ways off the end of the runway, rather than a smoking hole in the ground 2 miles off the departure end. An example of emergencies like this would be complete electrical failure or dual generator failure when WX conditions are low IFR, where now you're airborne and in the soup, but with nothing available to you. Would someone really want to take an aircraft airborne into that, rather than keep it on the ground and risk an overrun? Either way, you're in a crappy situation, but Id rather not turn a ground emergency into an air emergency, and make the situation 10 times worse, for an aircraft that likely isn't flyable to begin with.....or soon won't be flyable.

Granted, all of this is situationally dependant, and one could likely come up with 1000 disaster scenarios; but some of this stuff does need to be thought through a little bit, with caveats such that SteveC mentions. The worst feeling would have to be being airborne in an aircraft, where you're now wishing you'd left it on the ground. This kind of judgement when the situation calls for it, is what makes a PIC one who is "in command".
 
I suppose I'm a little bit leery of v1-The-Idea, myself. The Rules aren't set up to accept a minor accident as a possibility, but I'm sure as hell prepared to accept a minor accident, loss of license, and loss of career to avoid becoming a scattering of parts in a flaming hole. Every page of your performance data was written using a brand new airplane with near zero timed engines and a couple of test pilots who knew what was going to happen. And yes, sure, there's some "fudge factor" built in, but it's hard to calculate that when the engine quits at v1+5 on that last leg and your head is already at home drinking a cold one. Certainly it's a useful guideline.

PS. Just kidding, FAA, I obviously fly the aircraft in strict accordance with the POH. I was just testing these youngsters for any vestiges of free-thinking.

The fudge factor you speak of is the net performance, 2.5%climb gradient vs 2.8, or 40 ft per mile.

The biggest thing to remember, is that the climb profile in your book starts at 35 feet above the runway at the departure end, and that's where your safety numbers are calculated from. With the built in safety requirements for 121, and 135 operators, the odd of you only being 35 feet as you cross the departure end threshold are slim. Because of this, unless you fly really crappy profiles, dollars to donuts says you will likely do better than the book numbers. ( I know it's a sim, but when we do max perf. APG departures at KASE, KEGE, KPDX ect, the pilots always very the apg numbers. )
 
The fudge factor you speak of is the net performance, 2.5%climb gradient vs 2.8, or 40 ft per mile.

Yes, thank you.

(I know it's a sim, but when we do max perf. APG departures at KASE, KEGE, KPDX ect, the pilots always very the apg numbers. )

Heh. *shrug*. I've done Aspen and Eagle (and, say, Durango) in both the sim and real life, and let's just say the reality of the situation, particularly at Aspen, is not always quite the same as the sim when it's your ass in the seat and your name on the paperwork. The book says you can do it under 135 (just, of course) and you wind up rotating a few hundred feet from the end with radar power...that's a situation where I can see aborting after V1 for an engine failure.
 
I suppose I'm a little bit leery of v1-The-Idea, myself.

I see what you're saying Boris, particularly with the ASE situation where the aircraft, in fact, may not clear the hills. If the airplane simply will not fly, there's no choice but to reject above V1; it'll be ugly, but at least it'll keep you from becoming a smoking hole.

On the flip side, I've seen more than one poster state that pilots "unofficially" change the numbers to suit their needs. The example that I can think of is the post a while back wherein someone said that pilots were reducing V1 to 90 knots on runway 17/35 at PHL (6,500'). This shows a stark misunderstanding of what V1 actually is, and may actually create a smoking hole, rather than prevent one (90 knots may be below Vmcg, and reduce the screen height to, well, zero). It seems as though some "Type A" personality pilots (I'm in that club, too) revel in the idea of bucking the trend, and believe that they know better than the people who designed and tested the jet. In the case of V1, that number has been calculated, flown, tested, and certified by people smarter than me.

The next part isn't directed at you, Boris:

I can't speak for smaller bizjet types, but in the jets I've flown (one small, one medium, one big), the list of items that should result in a reject gets shorter as the aircraft accelerates. As far as I know, this has been the general trend in the industry for some years, and has lead to a reduction in overrun accidents. Such things prevent a blown tire from causing an overrun into the side of a hill (http://en.wikipedia.org/wiki/2008_South_Carolina_Learjet_60_crash), or a bird ingestion causing a hull loss in a 4 engine jet with 3 perfectly good engines (http://www.birdstrikecontrol.com/ne...t-brussels-on-may-25th-2008-rejected-takeoff/).
 
Yes, thank you.



Heh. *shrug*. I've done Aspen and Eagle (and, say, Durango) in both the sim and real life, and let's just say the reality of the situation, particularly at Aspen, is not always quite the same as the sim when it's your ass in the seat and your name on the paperwork. The book says you can do it under 135 (just, of course) and you wind up rotating a few hundred feet from the end with radar power...that's a situation where I can see aborting after V1 for an engine failure.

in ASE you wont clear by much... but you most likely will still clear, so long as you fly the engine out departure correctly. Off the top of my head, i can't think of any recent Turbojet crashes where the had the numbers, flew the profile, lost an engine at or immediatly after V1, and didn't actually have the performance to fly it out.

I can on the otherhand think of lots of accidents/incidents where the highspeed abort failed. Now, if you were talking an A340 going over the pond... if a passenger hiccups at v1, they're not gonna make it. (they take a stupid long take off roll).

if i worked the numbers, and know tht the numbers are good, post V1, its going to be something really bad that will make me abort. engine fail, i'm still going. in ASE of course, i'd be hoping for the APG departure off 15 of course.
 
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