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Rejecting A Takeoff After V1…why Does It (still) Happen?

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Rejecting A Takeoff After V1…why Does It (still) Happen?

Old 11th Dec 2010, 17:40
  #161 (permalink)  
 
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Forget the stories of 'daring do' and answer the question, what is your acceptable margin of additional required runway in order for you to abort above V1.

Mutt
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Old 11th Dec 2010, 17:57
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it's not hard to calculate runway needed to stop...on a post V1 abort...that's easy...
Really? Got any examples? You never know your knowledge might save lives one day.

I'd appreciate examples for:

V1+5kts, +10kts, +20kts, +30kts.

When do you do these calculations? Pre-departure or during the take off roll?
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Old 11th Dec 2010, 18:05
  #163 (permalink)  
 
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Johns7022

You fly a G-IV for an operator that lets pilots with NO type training act as a SIC? Leaving alone the fantastical idea that it's you being selected, what would the insurers or passengers say at that breathtaking bit of irresponsibility? At what distance can you read N numbers? I doubt it could be more 1,000 feet, so you didn't get that close, I know that. How did the SW B737 suddenly become a "jumbo jet"? If this was KLAX, how did ATC clear a visual and let your plane close that close? You can BS the fans, but you cannot BS the players. Here, we are all players.

Mutt. Ah yes, we some, no doubt cruder, versions of that kit, too.

GF
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Old 11th Dec 2010, 18:17
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Asking me if I can or can't do something isn't teaching. What I can and can't do is irrelevant. If it's so easy to calculate post V1 abort performance why does it matter what is past the DER?

Can you show us some examples or not?
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Old 11th Dec 2010, 18:30
  #165 (permalink)  
 
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Again, what range can N numbers be read? They are, by FAA standard, 12 inches high; are you telling me you can read something the height of a laptop at 1,000 feet. I doubt that ver much. I live in FAA and ICAO world, no competent operator of Gulfstream-class planes does the minimum under FAR 61 for training. All of our pilots have a full type rating or they don't fly, as required crew. Internationally, everyone must have a type rating.

I have not heard of an "open pilot waiver", but I do know of FAR 61.55 SIC qualification.

Still, I'd like to see how you calculate accelerate- stop distances.

GF
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Old 11th Dec 2010, 19:01
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So I pushed the yoke forward, applied enough counteracting control forces to keep the plane from flipping over....3 Times.
So who performed the Go-Around?

We operate about 150 aircraft ranging from 16,700 lbs to 870,000 lbs with some crews who initially trained on DC-3's, none of them are employed with 200 hrs. I know exactly how many engine failures we have had in the last 10 years, how many high speed aborts, how many incidents, how many overruns. We operate aircraft built by 7 aircraft manufacturers, and train crews in about 5 different countries.......... So i guess that we have enough experience to decide that YOU DON'T ABORT AFTER V1........

So did you do a reduced thrust takeoff in that G4?

Mutt
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Old 11th Dec 2010, 19:53
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You haven't given us any examples of post V1 perf. calcs.
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Old 11th Dec 2010, 20:15
  #168 (permalink)  
 
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Johns7022

You are the one here proposing new,"improved" performance planning, do show us professional engineers and pilots how you do it. I would be especially interested in how you use landing charts to calculate safe ASDR on a post-V1 reject. An unknown technique prior to 2100Z today
GF
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Old 11th Dec 2010, 20:40
  #169 (permalink)  
 
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JT – moderator; appreciating your forbearance with aspects of this thread, it is unfortunate that the original theme has been disrupted by less relevant discussions. May I suggest that the thread be split, that the latter discussions be removed elsewhere so that a more meaningful exploration of the original subject might continue to be explored?

This request is not intended to stifle a broad range of views. We all seek ‘truth’ and require open minds lest we are mistaken, but unfortunately it is difficult to debate currently accepted ‘science’ truths relating to post V1 RTOs without rational and logical presentation of alternatives.
I’m very interested in the ‘aside’ discussions as they provide insight to aspects of human thought, behavior, needs, belief, etc; possibly relating to problems of pilot training and progression of corporate pilots into commercial operations.

In other threads, some protagonists (including johns) express views that they are overlooked when seeking commercial positions, and that ‘cheaper’ and less experience first officers are being hired instead.
The corporate experience indicated in this thread is not as required by the airlines (nor the industry). This experience is not flying hours, but consists of personal qualities, airmanship, and human interaction which contribute to ‘attitude’. I recall that many airlines hire for attitude and train aptitude. I doubt that they would hire a pilot exhibiting a ‘know it all’, self centered view of operations, particularly if they could not explain opinions which differ from the accepted norm.

With respect to the thread subject, the distracting discussion could cause us question that deep and often intuitive beliefs of ‘us ground abiding humans’ might be hidden in our subconscious, only to surface in stressful situations - RTO assessments at high speed. However, this would only be another cause for RTOs after V1, suggesting that current training suppresses this innate behavior.

One argument is that we are approaching the limit of human performance and thus for high speed RTOs there should be greater margins of safety (not necessarily as expounded previously). Technology has and still continues to improve reliability, thus the human in comparison appears the weaker link. Human behavior can be improved, but not always dependably in increasingly complex operations.
Some might call for automation, which is by no means as dependable or flexible as the human, or do we persevere with the human in times of economic hardship, including a reducing source of ‘experienced’ pilots and fewer opportunities to gain experience, and even perhaps a diminishing passion for flying vs just a job; but again these are problems not solutions.
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Old 11th Dec 2010, 20:42
  #170 (permalink)  
 
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I've got a type, several in fact.

The real issue isn't just how much runway ahead but the conditions I would be pulling the broken plane into.

Taking a problem up into the soup, on a SID, in the mountains, picking up ICE, trying to get back down to minimums...as opposed to a nice easy roll out is a no brainer for me.

As far as acceptable margin...every runway is different, and weather conditions are different...it's not hard to calculate runway needed to stop...on a post V1 abort...that's easy...the real question is what's beyond the end of the runway....cliff, lava...over run, miles of flat Iowa cornfields...or just miles of nice flat dry runway...
I still want to know how you easily calculate runway required on a post V1 stop. You haven't answered because you can't.

I still want to know the reason that you will stop after V1.
Is it the weather conditions?
Or flying a SID?
Or icing?
Or flying an approach to minimums?
Is it what's beyond the DER? Does that matter if you're calcs are so good and easy to do?

All of those things we are trained to do in an aircraft designed and certified to do it.
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Old 12th Dec 2010, 00:36
  #171 (permalink)  
 
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Tell you what Lord..it's a slow night....

You load up a Citation 560, 9000 ft field, 1000 MSL...fly from PDX to DAL, full pax, call it ten peeps at 210 each, 35 lbs of bags each...

Plan the trip, come back with the numbers, show me you can plan a flight..then we will talk departure numbers...ok?
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Old 12th Dec 2010, 00:50
  #172 (permalink)  
 
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Show me a 10 passenger C560, first! Second, assuming you meant 8 passengers and 2 crew, your load exceeds ZFW by, at least, 150 pounds in an XLS+, more in an Excel. Third, the PDX 7 departure has a min climb gradient of 350 ft/nm or greater and numerous close-in obstacles, do you have a runway analysis provider? Fourth, the Excel cannot do this trip, probably in either direction, with your fictional payload. Any other bright ideas? I could do it in GLEX without even trying.

I've answered your BS questions, now answer one simple, do you calculate accel-stop distance on each take-off to justify a decision to reject after V1?

GF

Last edited by galaxy flyer; 12th Dec 2010 at 01:01.
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Old 12th Dec 2010, 01:16
  #173 (permalink)  
 
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If you are going to put a passenger on the dark, belted potty for 3+25, eastbound, and with a stop 5+00 westbound, be my guest. I don't do that, don't plan that way, either. Cessna says 8 seats plus a belted potty for a total of 9 passengers; add in the crew for a total of 11. Where are you getting 13? And the ZFW restriction means it doesn't matter what you say for seating, you reach ZFW FIRST!

It would be nice, if you knew what you were talking about.

GF

BTW, J_T, I think this thread is getting far off track--in fact, so far, it is out of HF range.
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Old 12th Dec 2010, 02:25
  #174 (permalink)  
 
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I wouldn't apologize for Brian I am sure he has found the Darwinian inevitable answer to his place in aviation.
Yep, and a very satisfying career it was too, working with professionals, which if you ever get to learn to fly you may have a crack at as well, though I doubt anyone would take you on because of personality issues.
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Old 12th Dec 2010, 04:16
  #175 (permalink)  
 
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How come the XLS has a ZFW of 15,100 pounds and you quote 12,200? Which one is a CE 560, an Encore or an Ultra? And how come Cessna's website shows both models as not being single pilot qual'd? My single pilot jet time is all tac fighter, btw, with a seat to solve all problems!

Gee, I thought 13 was about 4 too many in GLEX. I never flew the CE560, so knave learned that their website doesn't show all the possible interior arrangements. So, if an operator is stupid enough, he can put 10 valued employees in your careless hands. Being solo, I presume you wear an O2 mask above FL 350. No, not really, you don't follow any other reasonable regulations or good practices like climb gradients, the history of rejected take-offs, why that one.

Good luck, hope you don't make headlines!

GF

Last edited by galaxy flyer; 12th Dec 2010 at 04:28.
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Old 12th Dec 2010, 04:47
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13 max seats possible..
Two in Front, double club in back, remove potty for three pax seat in back.
Our config is two up front, double club, with potty. That's eleven...I said ten. I fly single pilot.
Bull****e. No you don't, cause the aircraft ain't certified SP. You don't fly nothin.
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Old 12th Dec 2010, 06:41
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As you are talking about the Cessna Citation 560, Encore/Ultra.... please have a look at....
Performance

It's worth noting that this is the latest in this family.... also note the following.." Single Pilot Certified No".... (but this doesnt apply to the older versions)

Now if you are talking about a different aircraft, please let us know.

Mutt

Last edited by mutt; 12th Dec 2010 at 08:06.
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Old 12th Dec 2010, 10:18
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There is no issue about flying the small Citation single pilot..... but look at the performance figures that are given for the Ultra ++. They don't appear to agree that you can operate PDX-DAL with 10 passengers.... I would presume that the performance of the older Citation 560s would be even less.


Mutt
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Old 12th Dec 2010, 10:43
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Worked for me when I ran it tonight...

Tell you what...I won't wander into your make and model if you don't wander into mine...ok?
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Old 12th Dec 2010, 11:14
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Look at the performance chart from Cessna, it shows Max Payload for the Citation 560 Ultra ++ at about 2,350 lbs, not your required 2,500 lbs. With this payload you can carry the max payload about 1180 nms in nil wind conditions. The distance from PDX-DAL is 1493 nms which today happens to be 1280 nms with a 75 kt tailwind (Jetplan data). That gives you about a 2000 lb payload. So how are you getting 2500 lbs?

No alternate? No reserve? What?

Mutt
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