What's V1?
Joined: Dec 1999
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From: Oop North, UK
In respect of runway length
(a) if the runway is longish compared to the particular aeroplane's needs, it may not become the limiting consideration for figuring a suitable V1. However, it will still be addressed as part of the process to determine the limiting factor as that process usually is addressed as sausage machine calculation.
(b) if the runway is shortish compared to the particular aeroplane's needs, runway length may, quite definitely, become a significant input into the determination of an appropriate V1.
(a) if the runway is longish compared to the particular aeroplane's needs, it may not become the limiting consideration for figuring a suitable V1. However, it will still be addressed as part of the process to determine the limiting factor as that process usually is addressed as sausage machine calculation.
(b) if the runway is shortish compared to the particular aeroplane's needs, runway length may, quite definitely, become a significant input into the determination of an appropriate V1.
Joined: Jan 2011
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From: England
TORA I guess is Take Off Run Available. So how can anything 'occur after TORA'?
Assuming that you have a stopway available (and the take-off has been properly planned), there will be enough space to bring the aircraft to a halt after the end of the TORA.
Fleet Manager
Joined: Apr 2001
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From: various places .....
put simplistically the V1 is then the max speed that the aircraft can stop in the remaining length
You might be putting the cart before the horse. The statement is fine if one is looking for max V1 and there are no other limits to prevent that being high enough to make the statement true. However that is not the only driver for V1 ..
If runway length is such that MTOW is not limited by runway length then it becomes largely irrelevant as far as V speeds go
.. providing that one still goes through the box ticking exercise to make sure that all the limitations are addressed ...
there will be enough space to bring the aircraft to a halt after the end of the TORA.
It may be the the earlier poster has a flawed understanding of TORA ? .. which includes a proportion of air distance after liftoff (either 1/3 or 1/2 the airborne distance to screen according to the particular rules which might be relevant).
You might be putting the cart before the horse. The statement is fine if one is looking for max V1 and there are no other limits to prevent that being high enough to make the statement true. However that is not the only driver for V1 ..
If runway length is such that MTOW is not limited by runway length then it becomes largely irrelevant as far as V speeds go
.. providing that one still goes through the box ticking exercise to make sure that all the limitations are addressed ...
there will be enough space to bring the aircraft to a halt after the end of the TORA.
It may be the the earlier poster has a flawed understanding of TORA ? .. which includes a proportion of air distance after liftoff (either 1/3 or 1/2 the airborne distance to screen according to the particular rules which might be relevant).
Joined: Dec 2011
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From: With Wonko, outside the Asylum.
I fear TORA and TODA have been confused. I won't say who has confused them... TORA is for taking off, not for rejecting and stopping. That's ASDA's job.
Again, it strikes me that the minutes and hours spent in debate here might better be spent in careful study of the relevant requirements etc...
Swatton's book is looking like a good one for the Christmas stocking!
Again, it strikes me that the minutes and hours spent in debate here might better be spent in careful study of the relevant requirements etc...
Swatton's book is looking like a good one for the Christmas stocking!
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From: various places .....
You are, of course, quite correct from a logical position .. however, while TORR may be scheduled for light aircraft (eg FAR 23.59) it doesn't appear to be common practice.
Thread Starter
Joined: Oct 1999
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From: UK
Taken at face value that question is rather worrying. It suggests that you have not heard of the terms STOPWAY or ASDA. If that is the case, you really will benefit from reading peter Swatton's book.
It should perhaps have said 'beyond TORA' rather than 'after TORA', the latter implying TORA is a speed rather than a distance. That's what got me confused (easy in this territory, which is not home country to a SEP pilot).
As said, Swatton's book on order.
Joined: May 2001
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If the new edition of Swatton was 10 quid I would be fighting to get the company to buy a personal copy for every pilot.
And if there was a fleet electronic option for it for the EFB I would get it for every aircraft. Better than reading the newspaper in the cruise.
And if there was a fleet electronic option for it for the EFB I would get it for every aircraft. Better than reading the newspaper in the cruise.
Joined: Aug 1999
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From: UK
A couple of real world examples for you.
For my day job I fly a 45T 100 seat twin for an international airline. We have a laptop on the flightdeck to calculate takeoff and landing performance at our destinations and alternates. We enter the weather (wind/QNH/Temp), Weight and runway and it calculates the speeds, flap setting and engine derate.
If we assume a departure from Heathrow (ie long runway) there will be a considerable split between V1 and rotate, probably 15 - 20kts. If we then tell the computer that 1500m of the runway is closed at the far end the Vr, V2 and Vfs speeds will stay the same but the V1 will move much closer to the Vr.
As others have alluded to above there are effectively two V1 speeds which can be better explained by calling them V1go and V1stop. V1go is the lower of the two and is the lowest speed tat which the aircraft can still accelerate to Vr within the available runway after the failure of an engine. V1stop is the highest speed from which the aircraft can still be brought to a stop within the remaining runway.
History has proved in air transport that attempting to stop from high speed (usually considered to be above 80kts) is frequently more dangerous than taking the problem into the air hence performance programs erring toward the lowest possible V1. There is a very good article at http://flightsafety.org/ap/ap_sep90.pdf
The 748 at Stansted is not an example of stopping after v1 however as in this case they were already past Vr and airbourne when they decided to land. The report is at Air Accidents Investigation: 3/2001 G-OJEM
For my day job I fly a 45T 100 seat twin for an international airline. We have a laptop on the flightdeck to calculate takeoff and landing performance at our destinations and alternates. We enter the weather (wind/QNH/Temp), Weight and runway and it calculates the speeds, flap setting and engine derate.
If we assume a departure from Heathrow (ie long runway) there will be a considerable split between V1 and rotate, probably 15 - 20kts. If we then tell the computer that 1500m of the runway is closed at the far end the Vr, V2 and Vfs speeds will stay the same but the V1 will move much closer to the Vr.
As others have alluded to above there are effectively two V1 speeds which can be better explained by calling them V1go and V1stop. V1go is the lower of the two and is the lowest speed tat which the aircraft can still accelerate to Vr within the available runway after the failure of an engine. V1stop is the highest speed from which the aircraft can still be brought to a stop within the remaining runway.
History has proved in air transport that attempting to stop from high speed (usually considered to be above 80kts) is frequently more dangerous than taking the problem into the air hence performance programs erring toward the lowest possible V1. There is a very good article at http://flightsafety.org/ap/ap_sep90.pdf
The 748 at Stansted is not an example of stopping after v1 however as in this case they were already past Vr and airbourne when they decided to land. The report is at Air Accidents Investigation: 3/2001 G-OJEM
Joined: Apr 2009
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From: down south
As said, Swatton's book on order.
I'm his illustrator and did all the performance diagrams for him (as well as the CAA CAPs).
Joined: May 2001
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Its a shame because most pilots now carry some form of ebook or tablet.
And the electronic flight bags all accept PDF or ebooks.
Lumping a book around isn't really practical or required these days. I certainly would have it on my kindle if it was available.
As its aimed at pilots it would be good to cater to how we as line pilots now operate.
And the electronic flight bags all accept PDF or ebooks.
Lumping a book around isn't really practical or required these days. I certainly would have it on my kindle if it was available.
As its aimed at pilots it would be good to cater to how we as line pilots now operate.
Joined: Apr 2009
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From: down south
That's not a decision for Peter - it's up to the publisher.
Bear in mind that it's primarily written for students of the ATPL syllabus.
I can 'phone him if you wish - he's only a few miles away.
Bear in mind that it's primarily written for students of the ATPL syllabus.
I can 'phone him if you wish - he's only a few miles away.
Joined: May 2001
Posts: 10,804
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not required a phone call, just put it into the mix.
Think they are missing sales because of it and to be honest it may be designed for that market but its price and content actually makes it more realistic for the line pilot reference market.
BTW I haven't seen the second addition but if you did the diagrams etc for the first, well done clear and to the point.
Think they are missing sales because of it and to be honest it may be designed for that market but its price and content actually makes it more realistic for the line pilot reference market.
BTW I haven't seen the second addition but if you did the diagrams etc for the first, well done clear and to the point.