ASpilot2be
Qbicle seat warmer
I thought you went Blue?
Sad Realization
- Thread starter Finhunter89
- Start date
Dugie8
Well-Known Member
Just took me too long to offer a class date, this fell in my lap and was too good to turn down.
ASpilot2be
Qbicle seat warmer
Gotcha. Well congrats on the new gig!
We had speed brakes....c'mon now. Useless as they were for ground, lol.
Hacker15e
Who am I? Where are my pants?
Yeah, you're right -- wasn't considering the boards.
ppragman
FLIPY FLAPS!
The problem that guys like me have with the pushback is that, yeah, sure in a jet or whatever, yeah, V1 is a hard number, but when I was in the left seat of the 1900 on a cold day looking at 10,000' of dry runway in front of me, I thought it was hilarious to take the thing flying when you have about 7500 to 8000 more feet of runway in front of you to stop in if you lose an engine in the 5kt window between V1 and Rotate. To be honest, I wouldn't even have to touch the brakes and I wouldn't go off the end. I always thought it was silly to even have V1 in that airplane, and thought it was hilarious when guys on this forum would tell me that you should "never-take-it-in-the-air-after-v1-no-matter-what!!!!1!!" To me, that kind of rigid, meat-computer type thinking doesn't have a place in professional aviation, but reading these forums sometimes one gets the impression that any critical thinking is dangerous. And while I will certainly be the first to say, "FTFM - or Follow the F-ing Manual" if one simply regurgitates the AFM without really knowing why things are the way they are, then that kind of defeats the purpose of even having a pilot there in the first place, right?
But that's the thing, there's a time and a place for everything, and if you're going to do something, be damned sure to have a reason for it. I mean, I don't fly the airplane, but I would bet you could abort a few knots after V1 in the Citation Mustang on a 10,000' sea-level runway and not have a problem, but that does put you squarely in test pilot territory - so you should have an answer for why you're aborting, and preferably one that is based on some sort of data so you can prove it.
Probability of an overrun during an abort after V1 depends on a lot of factors - to include how much energy you're dissipating with brakes versus their capacity to disperse, what kind of head wind you have, the runway slope, how rapidly the pilot acts to correct the problem, aircraft automation, and so on. In any case, you should be planning on taking an airplane flying after V1 except in very specific circumstances (a la 1900 on a 10,000' runway, or something that makes flying unreasonable).
That said.... consider this, what are some Vref speeds in these airplanes without flaps? I'd be willing to bet that they are higher than V1 in a lot of situations, and the airplane should be able to land without flaps and not kill everyone - so, if you really needed it to "not die" - that is to say something like the FO notices a fire in the wing after V1, or a volcano erupts in the mountains right off then end of the runway, or something else silly happens - there's certainly some ability to abort. Indeed, I'd bet a fella could even go as far as to say that you could find some guidance aborts after V1 by looking at no-flap landing data, or something of that nature. Not that that really helps you in the heat of the moment, because who is going to look up your no-flap landing distances and speeds (if they're even published) prior to takeoff and it still doesn't tell you if you're going to be able to make it in the rare event that your airplane has any of that published...but... it is something to think about.
I would also say that it is helpful to talk about and think about these sorts of things. I mean, there are times where taking an airplane flying after V1 can be a bad idea - they are exceedingly rare and probably not the sort of things we should be spending time on in training, but for hangar flying like we're doing here, they are a great tool to probe what happens when things go wrong. I mean, in part 25, they talk about waiting 2 seconds after V1 in terms of calculating accelerate stop distance - so how much extra speed does "1 potato, 2 potato" get you? 5kts? 10kts? I guess it would depend on the airplane, the situation, and so on. There's also a note in there that refers to 25.101 that says:
You should also be aware that:
So your brakes have to suck, and in your panic during the abort you cannot use reverse, so there is some margin built into the system - not a lot, but some.
Also, why you're aborting matters, if you're aborting after V1 because of an engine failure - yeah, aborting after V1 is typically silly, but there are times when it could make sense - especially under part 91. Consider this scenario where you end up going to some airport up in the mountains, there's no reg that I know of in part 91 that specifies you need to be able to meet the climb gradient on departure single engine (if there is someone please call me out), and while you could depart at 7:30am like your boss wanted to, he was delayed by another meeting and pushed back departure until 2:30 when it's 100°. Now, you can make the climb gradient out of there with both engines running, but not single engine. You've got 8,000' of runway left in front of you, and you experience an engine failure at V1 +5...what do you do? The best answer is don't even try to depart but if you do decide to go fly - is it better to shoot off the end of the runway at 25kts, or impact a mountain while trying to fly an obstacle departure you can't meet the climb gradient for? I hear stories from buddies flying corporate (or even some of the charter places out there) about these sorts of situations constantly - hell, in the C90 (where we don't have a true V1) there are times where it could behoove me to accept a bent airplane and broken pride then try to take it flying if I were in the high desert somewhere. It sounds unpleasant, but these are the things you should be thinking about before you conduct operations - "wow, it's freaking hot...and my OEI climb gradient is -200fpm....hmmmm."
A situation I could see in the 135 world for aborting a takeoff after V1 is nailing a deer/moose with the wing during the departure roll after V1. It's very plausible that you could take the airplane around, land, and have it be no big deal - but if you nail a 500lb moose calf at 135kts how well will that wing hold up on your trip around the patch? The airplane may very well rotate and fly for a little while, but then what? The airplane may still be airworthy - but you don't know for how long or how far it can go. Frankly, in that scenario, I'd probably rather take my chances shooting out into the weeds at the end of the runway at 30 or 40 knots than try to take a sick airplane on a joy-ride just because I was past a particular speed.
In a lot of ways these are silly examples, and there aren't too many good reasons why you should risk a high-speed abort after V1 - but there are reasons where it could be a good idea.
TL;DR - Don't abort after V1 unless there's a damn good reason to do it, but sometimes it's better to be a test pilot and risk an overrun than take a sick airplane flying, or "think before you go fly."
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Boris Badenov
Fortis Leader
You think too much, #9834243, back to training for you. Press the buttons in the right order and just get the freaking banana this time, ok?
PhilosopherPilot
Well-Known Member
That's unfair, and you know it.
There are absolutely times when rejecting past V1 would be the "correct" action when you look back with the benefit of hindsight. Those examples will be very very rare. Most of the time a reject past V1 will be the wrong action. No one on here seems to disagree with that.
In reject scenarios, there just isn't much time to think. Training kicks in and if your training has you do it the same way every time, you have a chance of not effing it up. The rejected takeoff go/no go decision is one if the most repeated items during training. This year in recurrent we spend a good hour just on rejects and go/no go scenarios.
So:
1. Airlines have to build procedures to the lowest common denominator.
2. Airlines have to build procedures that manage the risk in the system, not individual flights.
3. The safety record of 121 vs 135 ops speaks for itself.
Maybe flying like a monkey makes me less manly or whatever, but if it makes me safer, gimme another banana. This job isn't about ego.
[emoji529][emoji529][emoji529][emoji529][emoji529][emoji529]
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Boris Badenov
Fortis Leader
Wait, Pat puts the time in to write a freaking treatise, and you're responding to me? I don't have an opinion about your manliness, Mr. Internet Stranger. Would prefer to remain ignorant of the information necessary to make a determination one way or another. For all I know, you're freaking King Kong. I just thought what he posted was pretty right-on in a lot of ways. What do you say?
PhilosopherPilot
Well-Known Member
My response was to both, frankly. I'm just on my phone and too lazy to quote you both in the same post.
I see this just like the QRH debate. Are there times when staying on script is the wrong action? Of course there are, but they are less likely than the times that going off script will kill you, so we train to the safest overall option.
jynxyjoe
Queso King
@ppragman
That was a long way to get into a discussion onto V1, and much of your example is outside my area, or completely outside a part 25 aircraft. I do know a little bit about a 1900, and even in that airplane the CA and FO both briefed aborting past V1 had to be for "a good reason" to paraphrase you. Those reasons? Flight control malfunction, wing falling off, Godzilla. If one were to "simply regurgitate the manual" they would need to regurgitate the part in every book I've read so far alluding to "This book can not reference every single situation that may arise in use of this aircraft for flight. It may be required the crew deviate from parts of the book to complete the flight safety, the pilot is expected to use his or her best judgement." Sometimes you pretend like book readers are meat computers, but if someone reads for comprehension instead of, barking at print, they would understand what you're saying. I read the book, I understand what you're getting at.
Like @Boris Badenov said, you've written a long post, taken some time to illuminate your arguments, you deserve an answer. This question comes up for a lot of new hires, I've found, once you get into the system you'll see actual events that will probably cause you to rethink some of that.
For a 121 guy, we're pretty far removed from the 91 world, for good reason. As @PhilosopherPilot pilot has said it's about the safety record. We aren't doing 3000ft fields in citations. Different equipment have different requirements. When we had a Saab in the Mesaba world the checkairmen and training department focused in on aborts, discussed all the times guys did abort past V1 and what that looked like (not good 99%) then they would tell you "Hey, it's a small airplane on a long runway, if you need to do it" and then show us one example where the NTSB credited the crew for aborting past v1, exiting the runway, and that was the best case scenario. I can't speak for every operator. On RJ's, you're close on a lot of fields, because of our flexing. This ain't the 1900 where we set 3950 torque, let it build to 4300 because we can (20second transit no write up) and go lunar at 12K pounds stick about 160 knts 25 degrees up in the air, or hang it on the props at 140 because no one is in the back on a cold day to get that 40degree nose up and about 8000ft/min climb rate. We takeoff flexing or derated. We use the 10,000ft , or the 7k foot to save money. You are going to be bumped up against your V1 more often than not, so respect it. You, pat, aren't sitting on V1 most days, airline guys (if flexing) spend a lot of time near V1.
Also, V1 is normally, fire/failure/smoke/controlability. If the Lav smoke went off I'm stopping until I make sure I'm not going around the pattern with a fire. If I yank back and the plane acts like nothing's controlling it, we're stopping. There's a lot of weird painting things (new paint job) that can cause you're wing to not create lift properly, so you truck up to V1 and the plane won't lift, crap, thank God for the autobrakes.
Anyway, 121 guys don't get into much hanger talk. It's regimented and training departments have ways they want you to think. Rarely does it lead you wrong. Mesaba's 60 something years never led us wrong. Southwest had a long run that never led it wrong. The airplanes fly 12-16 hours a day 7 days a week, 5000 hours a year? Flight crew is going to put in 750 hours a year? So... 375 takeoffs a year, maybe 30% near V1? (obviously ATL to DTW, DTW 22R to SLC to LAX back to ATL for a mainline guy once every two weeks wouldn't have that V1 problem) 112 TO a year near V1? We train the hell out of it and that's most of our hanger talk.
You're flying in a different world than a lot of us. There's not a lot of common ground here unfortunately.
That was a long way to get into a discussion onto V1, and much of your example is outside my area, or completely outside a part 25 aircraft. I do know a little bit about a 1900, and even in that airplane the CA and FO both briefed aborting past V1 had to be for "a good reason" to paraphrase you. Those reasons? Flight control malfunction, wing falling off, Godzilla. If one were to "simply regurgitate the manual" they would need to regurgitate the part in every book I've read so far alluding to "This book can not reference every single situation that may arise in use of this aircraft for flight. It may be required the crew deviate from parts of the book to complete the flight safety, the pilot is expected to use his or her best judgement." Sometimes you pretend like book readers are meat computers, but if someone reads for comprehension instead of, barking at print, they would understand what you're saying. I read the book, I understand what you're getting at.
Like @Boris Badenov said, you've written a long post, taken some time to illuminate your arguments, you deserve an answer. This question comes up for a lot of new hires, I've found, once you get into the system you'll see actual events that will probably cause you to rethink some of that.
For a 121 guy, we're pretty far removed from the 91 world, for good reason. As @PhilosopherPilot pilot has said it's about the safety record. We aren't doing 3000ft fields in citations. Different equipment have different requirements. When we had a Saab in the Mesaba world the checkairmen and training department focused in on aborts, discussed all the times guys did abort past V1 and what that looked like (not good 99%) then they would tell you "Hey, it's a small airplane on a long runway, if you need to do it" and then show us one example where the NTSB credited the crew for aborting past v1, exiting the runway, and that was the best case scenario. I can't speak for every operator. On RJ's, you're close on a lot of fields, because of our flexing. This ain't the 1900 where we set 3950 torque, let it build to 4300 because we can (20second transit no write up) and go lunar at 12K pounds stick about 160 knts 25 degrees up in the air, or hang it on the props at 140 because no one is in the back on a cold day to get that 40degree nose up and about 8000ft/min climb rate. We takeoff flexing or derated. We use the 10,000ft , or the 7k foot to save money. You are going to be bumped up against your V1 more often than not, so respect it. You, pat, aren't sitting on V1 most days, airline guys (if flexing) spend a lot of time near V1.
No, no we won't be thinking of that, we will never think of that until we're back in a type aircraft that does that. We won't entertain it in a 121 environment. I know it's a problem in non transport category aircraft, it is not in this world. Using that example harbors no meaning to me anymore. 8-10 years ago in an apache? Yeah. That is not an accurate reason in 121 ops, that I've ever witnessed. Even a 1900C/D fully loaded on a hot day will still tow an empty Saab 340 behind it in the climb with one engine and severe idealized wind shear. An RJ for instance will always climb, or else you'd be climb limited and we'd lose some people.
That two seconds is for normal human reaction time only. It's like following a car 1/2 car length at 55mph. You will slam into the bumper before the brain understands what the eyes tells it, and gets the signal to the foot to move off the accel and hit the brake. That's why we wait, and it's not speed, it's the 220 feet you just lost behind you and the extra 5 knots you picked up, leaving you an extra 700 ft further down the runway than aborting as close to V1 as possible. Some companies call V1 5 knots before. That's my preferred method.
Also, V1 is normally, fire/failure/smoke/controlability. If the Lav smoke went off I'm stopping until I make sure I'm not going around the pattern with a fire. If I yank back and the plane acts like nothing's controlling it, we're stopping. There's a lot of weird painting things (new paint job) that can cause you're wing to not create lift properly, so you truck up to V1 and the plane won't lift, crap, thank God for the autobrakes.
I would fix as such above.
Anyway, 121 guys don't get into much hanger talk. It's regimented and training departments have ways they want you to think. Rarely does it lead you wrong. Mesaba's 60 something years never led us wrong. Southwest had a long run that never led it wrong. The airplanes fly 12-16 hours a day 7 days a week, 5000 hours a year? Flight crew is going to put in 750 hours a year? So... 375 takeoffs a year, maybe 30% near V1? (obviously ATL to DTW, DTW 22R to SLC to LAX back to ATL for a mainline guy once every two weeks wouldn't have that V1 problem) 112 TO a year near V1? We train the hell out of it and that's most of our hanger talk.
You're flying in a different world than a lot of us. There's not a lot of common ground here unfortunately.
ppragman
FLIPY FLAPS!
Nice! Thanks!
jynxyjoe
Queso King
ppragman
FLIPY FLAPS!
Lol, one of the things I'll say though is that the guy talking about ARGUS/Wyvern or whatever was talking about corporate flight departments when he talked about that interview question that spurred all of this. Then all the hate from 121 guys, which I didn't really think was warranted to @Hacker15e. I mean what's your typical ref speed and your typical v1 in what you're flying?
jynxyjoe
Queso King
Honestly i didn't read the first 14 pages. When I opened it up at pg 15 it was such hot garbage I couldn't help myself; sucked in.
ppragman
FLIPY FLAPS!
I think this thread started out talking about how pilots at Ameriflight were the best on earth...but there are so many posts...
SpiceWeasel
Tre Kronor
That was me
Uncorrected dry data: Ref speed at Flaps 5 is anywhere between (min landing weight) 109 KIAS and (max landing weight) 133 KIAS which gives 6670 to 8870 landing distance with Lo Decel Rate Brakes. With the wind additive our Vapp may be as low as +5 to +20 above the ref.
For takeoff, I honestly don't know - I'm too new to give a range that would make sense even to me. But an example I found is for a weight range of 94700 to 96300, V1 is 135. This particular solution is climb limited and Flex is 32C. Unsure what N1 that gets (it's not listed).
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