High Speed Aborts

[tac airlifter]

As with most aviation discussions, the answer to a high speed reject is ... it depends. It depends on what aircraft you fly, on what speed you're at and what your performance data allows. A statement that may apply to a heavy weight tanker doesn't necessarily apply to a light weight herc.

For example, lets say you touch down fast and long, start to advance the power and someone calls "reject!" Do you honor the call? Based on this thread most of you guys say no. Now for the rest of the information-- you are very light weight and were doing touch and go's on the shuttle skid strip which is 15,000' long and you have 12,000' in front of you. The reject was called because a crew member is suffering a seizure and passed out in his vomit. WX is bad and if you take it airborne you'll be in the instrument pattern versus taxing off the active to the firestation right next to the runway. With this additional information it would appear the best choice is to honor the call. Thats an example of how any number of variables can effect what is the "best" option for your particular circumstance. I understand the value of having predetermined decisions for a lot of scenarios, but sometimes you also need the SA to act according to the situation.

As for the incident that started this thread, I determined it safer to allow the situation to continue and debreif once we cleared the active runway. Is anyone who wasn't there really going to question my call? As for getting a Q3 for doing something stupid, IP's don't have the authority and she was well known for her shenanagins; she was deputy GP/CC and punishment was not going to happen.

Edited April 28, 2009 by tac airlifter

[Guest Miclhstrase]

I am not familiar with the original thread, but has anyone brought up the T-38 incident with the aborted take-off and barrier engagement? That was a aborted right before rotation, and if it wasn't for that barrier, they were screwed. How come the decision was made to abort if the engines were still operational and what happened to this stud?

http://www.patricksaviation.com/videos/Contrail_25/3508/

[TacAirCoug]

As for the incident that started this thread, I determined it safer to allow the situation to continue and debreif once we cleared the active runway. Is anyone who wasn't there really going to question my call?

For my part, not at all. Sounds like you made a good judgment call, and none of us were there to say otherwise. For what it's worth, I don't think anyone was really questioning your actions. My comments were critical of her, and aimed at the discussion asking the general question, "Why not abort on a touch and go?"

[Guest T2 Ernie]

New guy here - hope you don't mind me butting in on post one. Actually came here for a travel question, but saw this topic & thought I'd throw my two cents in.

The answer, as always, is - it depends.

What is the situation? Will taking it airborne be a greater hazard than trying to stop in the concrete available? What is off the end of the runway if we get that far? Etc.

You can, of course, Monday Morning Quarterback any situation.

As a career 130 guy (slicks and AFSOC), I am typically stop oriented, but will make mental adjustments based on the situation. Every plan and situation is different.

Something I don't think we (big USAF we) are good at is training to fail. We train to succeed and consequently struggle to adapt when we fail. What I mean by this is every time I take the runway, I assume I'm going to abort until I take off. Every airdrop is executed with the assumption I'm going to no-drop until I hear "load clear" and every landing is assumed to be a go-around until the wheels touch down. It's a mental state of mind we don't teach well. We tend to focus on how to make it happen, how to accomplish the mission, and we pass this on to the younger crewmembers and consequently, when things go pear-shaped, we're not as prepared as we could be and we lose time. Time, in these critical moments, is precious. This is where your "2 second reaction time" comes from - the time to process that you're failing and react to it because it's not the norm.

Ok - old guy rant off - going back to seeing if I can find my PCS question..... ;)

[Guest Cap-10]

I am not familiar with the original thread, but has anyone brought up the T-38 incident with the aborted take-off and barrier engagement? That was a aborted right before rotation, and if it wasn't for that barrier, they were screwed. How come the decision was made to abort if the engines were still operational and what happened to this stud?

http://www.patricksaviation.com/videos/Contrail_25/3508/

Not monday morning QB'ing, but...

I have been getting the feeling that folks on this board like to bitch an moan about stuff, but don't offer solutions.

In an attempt to actually have a discussion, and maybe, just maybe teach a young pup something, I'm going to attempt to set this up as if its the debrief setting post flight.

Didn't see any yaw indidicating a loss of thrust on the left side, but I can't say one way or the other what the status of the left engine was.

From what I did see, he either felt the thump, saw the black streak go down the left side, or got some lights, etc in the cockpit...but whatever it was, he thought he needed to abort.

Without knowing all the details, its tough for me to say if the root cause is: 1) his mis-analyziation in the first place, resutling in the wrong procedure being applied, or 2) the actual abort procedure execution.

Mis-analyzation Root Cause: If he had two good motors and he was above abort speed, the he made the wrong decision. If he had one good motor, but above abort speed, he still made the wrong decision.

Abort Procedure Execution Root Cause: He "Communicated" before he "Aviated". He took the bird at 142 indicated. But he spends the next 6 seconds (approx) telling the IP "we took something" then answering his "What?" with another "we took something, I'm going to abort". In the following 6 seconds, they have accelerated to 169 knots. Make the f-ing decision, and get the abort going...you can tell me about it once we have stopped! If my memory serves me correctly, there is only a 3 seconds of time built into the abort numbers, allowing for analyzation, ripping the throttles to idle, and the engines physically spooling down. During this 3 seconds, it is assumed that you are still accelerating. In this case, it appears he used more than 3 seconds....

The Fix: How to make this better the next time you find yourself in this situation:

If I had two good motors and was above abort speed, I would have pressed with a normal take-off.

If I only had one good motor, but above abort speed, I would have lowered the nose to a 3 point attitude, and rotated at SETOS (or approx 1500 feet remaining), retracted the gear, and then flaps at SETOS +15.

If all of this occured below max abort, then the procedures needs to happen a lot quicker than 6-9 seconds after the bird goes down the motor.

With all of the above "continue" scenarios, remember that this is a formation take-off, but since you are handling an A-B-normal situation, remember to check your throttles in MAX, treat the centerline as a brick wall, and perform your separate take-off.....this possibly thrust limited situation is no time to be worrying about being in min-ab trying to stay in postion with flight lead.

Cheers,

Cap-10

[Guest Miclhstrase]

Abort Procedure Execution Root Cause: He "Communicated" before he "Aviated". He took the bird at 142 indicated. But he spends the next 6 seconds (approx) telling the IP "we took something" then answering his "What?" with another "we took something, I'm going to abort". In the following 6 seconds, they have accelerated to 169 knots. Make the f-ing decision, and get the abort going...you can tell me about it once we have stopped! If my memory serves me correctly, there is only a 3 seconds of time built into the abort numbers, allowing for analyzation, ripping the throttles to idle, and the engines physically spooling down. During this 3 seconds, it is assumed that you are still accelerating. In this case, it appears he used more than 3 seconds....

That's what I am a bit confused about. The stud seems to rely on the IP's input before making his own decision. Shouldn't the stud be fully aware of the emergency procedures prior to ever taking the controls of an aircraft? I have not begun my PPL training yet, although I will in a matter of weeks, but from what I understand, most trainer aircraft have dual sets of controls and the IP can take control of the aircraft at any time. If the IP disagreed with the abort decision, then wouldn't he have just lowered the nose, increased thorottle, and take off at SETOS? Or is there just no time to transfer controls in this type of situation, especially given the fact that it took a matter of seconds to communicate the situation to the IP?

On a side note, why does the IP instruct the stud to release the breaks prior to contact with the barrier? Are they trying to avoid a fire or skidding?

Edited April 29, 2009 by Miclhstrase

[ol-IEWO]

Yes, it sure does depend on what you're flying. I flew one aircraft that if you lost one of the two engines, you aborted. Reason was we were so under powered, we didn't reach single engine flying speed until about 45 seconds after takeoff. We were non-center line thrust, one engine under each wing.

The only abort I can recall in F-4's was when we forgot to reset the aircondition to take-off and the whole cockpit fogged. Other than that we took off, burned fuel while all the experts told us what not to do. We usually hooked the approach end cable on landing.

[matmacwc]

T-38 abort, IP should have taken it and continued T/O, my 2 cents...

[Kaman]

I think it is important to recognize that everytime you take the runway you are facing an abort scenario. Conversly, everytime you land you are facing the possibility of executing a go-around or rejected landing. Cres often brief abort criteria, but don't always follow it when faced with a malfunction or botched landing. So, we must try to mitigate the hazard by using good planning and decision-making before we even sign for the airplane. We have all been faced with pressures to complete the mission, hop, flight, etc... And, pilots are no less suceptible to "get-home-itis" than the rest of the population. Knowing your airplane is also a key to understanding the difference between having a flyable airplane and one that requires a dangerous high-speed abort. I am not a military aviator, but I did fly as an enlisted aircrewman for 20 years in the Navy. Currently, I fly a SAAB 340 on a 121 certificate and have also been a check airman on the Beech 1900, so my perspective is going to be different than a heavy driver or tactical jet pilot. I have really learned alot on this site and enjoyed reading this thread.

[zrooster99]

Best thread I've seen in a while! For the other '17 bubbas, what do you think about using 80kts as a checkpoint vice just using Vgo? Personally, I think 80kts is kind of arbitrary and Vgo is based on an actual numbers crunch. I understand to a certain degree why some people use it, but I like to keep things as simple as possible. If it makes sense to abort, it makes sense to abort. If it doesn't, it doesn't. I usually talk about some things we WON'T abort for and then go on to say, call what you see and I'll make the decision.

[Butters]

Best thread I've seen in a while! For the other '17 bubbas, what do you think about using 80kts as a checkpoint vice just using Vgo? Personally, I think 80kts is kind of arbitrary and Vgo is based on an actual numbers crunch. I understand to a certain degree why some people use it, but I like to keep things as simple as possible. If it makes sense to abort, it makes sense to abort. If it doesn't, it doesn't. I usually talk about some things we WON'T abort for and then go on to say, call what you see and I'll make the decision.

The 80 kts technique is an old one that seems to have survived somewhat. At 80kts when throttles go into clamp mode and that seemed like a good time to match a Go-Oriented decision point since we call "80kts". Honestly, the C-17 like the C-130 is very stop oriented. Even if we had several blow tires, some hesitation, and a Great Dane or two in the back, we would not have any trouble stopping on 90% of the runways we operate on. It is still good to talk about though, since certain emergencies can affect your stopping power and can cause you more trouble trying to stop rather than go.

I like the FAA and Boeings recommendation of 100 kts, but still we have plenty of excess stopping power. One thing that needs to stop in the C-17 community is the negative press blow fuse plugs get. If you have a high speed abort and blow your fuse plugs, that is a good thing. That means they worked. Seems every time I hear someone blew a few tires, everyone thinks they screwed up. Well, sometimes they did... riding the brakes, landing without checking your brake temps after a recent takeoff, ect. However, I am afraid someone is going to go light on the brakes because they are afraid of blowing fuse plugs and end up in the dirt.

[war007afa]

A few inputs I have (like them or leave them, you won't hurt my feelings either way):

1) GO speed is exactly that: GO speed. PASS GO, TAKE OFF, collect $200. We base our reject speeds on the RUNWAY WE HAVE AVAILABLE. For you Herc guys, also remember the considerations that are put into your reject numbers. So you have a low-pitch stop fail to retract; you leave it in ground idle and reverse the two symmetricals, just like the considerations state you will. At 0.000069 KIAS above the GO speed, you take it airborne, plain and simple. You have entered the realm of what the numbers in front of your FE from his 1-1 state are no longer safe to reject the T/O and need to start drinking water for that upcoming urinalysis.

2) REJECT on a T&G: I brief in my T&G brief to NEVER call reject on a T&G. Do so, and when we get back to debrief I'm going to punch you in the junk. Let me know what the problem is with a brief description (i.e. "we have a crewmember medical emergency") and I will make the decision based upon my next point:

3) ENERGY: Touch and go's are all about energy. This is where we make our big money as pilots. In the gunpig, like all C-130s, we have the luxury of instantaneous throttle response because all we are changing is our prop pitch (engines always 100%). Whether your airplane has that luxury or not, you have to analyze your energy state in order to make an educated decision as to whether you are going to stay or go on a T&G. You know where you touched down, you know what your airspeed was at touchdown, you know how much runway you have left. This drives home the importance of touching down on aimpoint, centerline, and airspeed. Outside of those parameters, go around! Don't accept putting yourself into those unknown regimes and making the potential for catastrophy worse by accepting bad landings in the first place. Take out one more variable for you to have to consider when you have that high-speed emergency and have to make the decision.

I think that if you live by most of these techniques that I hold dear, the likelihood of you departing the prepared surface during one of our most critical phases of flight drop exponentially. Rant off, standing by your spears.

Cheers.

Edited for the fact that there is no "a" in "luxury"

Edited May 1, 2009 by war007afa

[disgruntledemployee]

You know where you touched down, you know what your airspeed was at touchdown, you know how much runway you have left. This drives home the importance of touching down on aimpoint, centerline, and airspeed.

Hey Bud, that is why it is wise to have a real good abort distance number for a T/G. An easy one is 4000. If you got it, and you don't like your situation, call it and stop.

On every TO, I think abort abort abort until "go" and then I think go go go. I'm much less hesitant because of it.

Out

[Guest SOF HERK]

1) GO speed is exactly that: GO speed. PASS GO, TAKE OFF, collect $200. We base our reject speeds on the RUNWAY WE HAVE AVAILABLE. For you Herc guys, also remember the considerations that are put into your reject numbers. So you have a low-pitch stop fail to retract; you leave it in ground idle and reverse the two symmetricals, just like the considerations state you will. At 0.000069 KIAS above the GO speed, you take it airborne, plain and simple. You have entered the realm of what the numbers in front of your FE from his 1-1 state are no longer safe to reject the T/O and need to start drinking water for that upcoming urinalysis.

A few comments from the peanut gallery - Refusal speed is based on ASDA (to use current terminology), which is normally the runway, plus any overrun stressed for you. And in the mighty C-130 whisper-pig, Refusal speed typically exceeds GO speed by a wide margin (often limited by NW speed). So I am neither in unknown territory, nor unsafe territory if I accelerate past GO speed and elect to abort - so long as I'm below refusal speed I should stop within the concrete available. And I'll have to double-check my -1-1, but I don't think my abort is based on LPS failing to retract - it's based on 2 in reverse, one in ground-idle, one windmilling and max anti-skid braking (but I don't have a -1-1 handy).

3) ENERGY: Touch and go's are all about energy. This is where we make our big money as pilots. In the gunpig, like all C-130s, we have the luxury of instantaneous throttle response because all we are changing is our prop pitch (engines always 100%). Whether your airplane has that luxury or not, you have to analyze your energy state in order to make an educated decision as to whether you are going to stay or go on a T&G. You know where you touched down, you know what your airspeed was at touchdown, you know how much runway you have left. This drives home the importance of touching down on aimpoint, centerline, and airspeed. Outside of those parameters, go around! Don't accept putting yourself into those unknown regimes and making the potential for catastrophy worse by accepting bad landings in the first place. Take out one more variable for you to have to consider when you have that high-speed emergency and have to make the decision.

Back the go-around bus up a minute...how long is my runway? If I'm going to a short strip, you're spot on. If I'm going to Little Rock's 12,000 main runway, or Albuquerque's 14,000 runway, I'm very UN-concerned about aimpoint-airspeed-centerline-energy management - other than pride & ego. From a practical perspective, I can touchdown as fast as I want - 2 miles of concrete to stop the mighty Hercules is a bit more than simply adequate. Context, brother, context. ;)

2) REJECT on a T&G: I brief in my T&G brief to NEVER call reject on a T&G. Do so, and when we get back to debrief I'm going to punch you in the junk. Let me know what the problem is with a brief description (i.e. "we have a crewmember medical emergency") and I will make the decision based upon my next point:

This is a pretty standard briefing item these days, I think - read on.

Hey Bud, that is why it is wise to have a real good abort distance number for a T/G. An easy one is 4000. If you got it, and you don't like your situation, call it and stop.

Your plan, your decision - personally, I view 4,000 feet as excessively conservative. What is my landing ground roll for my current weight? If you're doing T&G, you're probably <130K and your LGR is probably <2000'. Think about that for a minute. I'll wait. ;)

I add a bit of a pad based on what I'm doing and where I touch down, etc, but I use anywhere from 2000-3000 feet - depending. But you have to have the S/A to know where you're at, what you're doing, how you're doing, etc. (or, more fun, what your student is doing TO you!)

Folks like to look for a one-size-fits-all answer to a dynamic situation. Yep, 4K will work nearly every time, but think what you're giving up...potentially take a really sick plane into the air because you were actually too conservative - sounds silly when put that way, don't it?

On every TO, I think abort abort abort until "go" and then I think go go go. I'm much less hesitant because of it.

Outstanding technique (and one I use and teach) - now do it for airdrops, approaches, landings, etc. Plan to fail until you succeed!

If we're going to be Herk specific, one of my pet peeves is folks who are too generic instead of being specific. It demonstrates a lack of knowledge/SA/airmanship IMO. For example, shutting things things down in flight idle that don't need to be - you just created a directional control problem for yourself and, you could make a case, you're not IAW the dash-1. There's really only three things that need to be shut down in flight idle - prop low oil light, overspeed, & flameout - everything else is going to "follow" you into the ground range and not create a directional control problem (which is why we shut certain things down in flight idle). My absolute highest order pet peeve is the brief where someone says, "If you don't know what it is, just call it a prop, and we'll shut it down in flight idle" - WTF,O? I refer you back to the only three things that need to be shut down in flight idle...those are all very easy to identify (and often obvious to the flying pilot before anyone notices it).

Rant off...

[booze]

My absolute highest order pet peeve is the brief where someone says, "If you don't know what it is, just call it a prop, and we'll shut it down in flight idle" - WTF,O? I refer you back to the only three things that need to be shut down in flight idle...those are all very easy to identify (and often obvious to the flying pilot before anyone notices it).

Rant off...

For initial t/o briefings, I don't like the "prop, engine, system, or load" thing. Just say "reject" and tell me in plain English what you see, and I'll make the decision. Example: I'm on the bunk, gray-haired EP is in the right seat, young LT in the left...TIT gage slips out on t/o roll and is hanging there, and only the EP sees it. Gray-haired EP calls reject. Young LT does the right thing and pulls throttles to flight idle, waiting to hear why. Gray-haired EP stares at gage thinking, "is this a prop, engine, system, WTF is this?" What seems like thousands of feet of runway go by. An example of an experienced dude trying to think too much because we tie our hands with the standard briefing and try to put rejects into a category. As SOF HERK says, there are very, very few situations that call for a shutdown in flt idle anyway. Make it simple and just call what you see....as if it's a t&go, but with the "reject" call.

[disgruntledemployee]

Your plan, your decision - personally, I view 4,000 feet as excessively conservative. What is my landing ground roll for my current weight? If you're doing T&G, you're probably <130K and your LGR is probably <2000'. Think about that for a minute. I'll wait. ;)

I add a bit of a pad based on what I'm doing and where I touch down, etc, but I use anywhere from 2000-3000 feet - depending. But you have to have the S/A to know where you're at, what you're doing, how you're doing, etc. (or, more fun, what your student is doing TO you!)

Folks like to look for a one-size-fits-all answer to a dynamic situation. Yep, 4K will work nearly every time, but think what you're giving up...potentially take a really sick plane into the air because you were actually too conservative - sounds silly when put that way, don't it?

Sorry, guess I should have provided a realistic, real-world number for the C-130. Since I was merely illustrating a concept, I used a number fried into my brain when I flew a jet, that being...4000. But yes, you are correct, 4K is conservative for Herc.

The reason we like a one-size-fits-all performance factor is for the rare situation when we may not have time to think much. You may think that its lazy, or a lack of SA, but those nice numbers keep thing safe. For example, I know that I can pull a 60/2 at any weight at 180 kts.

I'd love to continue the duel, but I've got to go.

Out

[Guest SOF HERK]

For initial t/o briefings, I don't like the "prop, engine, system, or load" thing.

If I'm in the left seat, I really don't care what I hear. I'm going to initiate the reject & now I just bought time to analyze the situation. Someone calls a prop, so be it. I'll evaluate. I brief the only things I'm definitely going to shut down in flight idle are the three I mentioned, so if I don't shut down "your" prop call in flight idle, I've already briefed that...

Sorry, guess I should have provided a realistic, real-world number for the C-130. Since I was merely illustrating a concept, I used a number fried into my brain when I flew a jet, that being...4000. But yes, you are correct, 4K is conservative for Herc.

Sorry - thought we were talking herks. Point taken.

The reason we like a one-size-fits-all performance factor is for the rare situation when we may not have time to think much. You may think that its lazy, or a lack of SA, but those nice numbers keep thing safe. For example, I know that I can pull a 60/2 at any weight at 180 kts.

Things don't happen that quickly in a Herk (although it may seem like it at times...). It's a rare instance when you have to react instinctively & there are good crutches for those situations. I don't like the one-size-fits-all approach because it's typically taught first as a "rule of thumb" and inexperienced folks tend to rely on it instead of developing the SA to know why they're doing what they're doing when they're doing it...not saying they don't work, simply that they (can) foster the wrong approach to flying.