Balanced Field Length, V-speeds

[Rokit88]

Hmm...Falcon..Airbus...

me thinks this has something to do with being french. Am I on to something?

Anyway that would be a mouthful to say at one time.

Make the call easy "FLY NOW!"

 

[Hugh Johnson]

V2/Vr on the Falcon, my bad.

 

[Gear Up!]

Regardless in any situation If you shell one at V1 you go. Even If you have a long runway and you THINK you have enough room to stop, I always go. This way there is no mind set in taking split second decisions and debating to go or stop. You could have a blown tire and take out the squat switch which would prevent t/r, ground spoilers, ect from being utilized. It prevents the risk of running off the end or departing the side of the runway. What is the harm of just taking it in the air? She will Fly, If you are within your weight limitations. On Shorter runways 5000 or less 90 knots is my abort speed. Anything after I take it in the air. But once again, I guess until we are in the situation, thats how the story goes..

 

[snow-back]

Regardless in any situation If you shell one at V1 you go. Even If you have a long runway and you THINK you have enough room to stop, I always go. This way there is no mind set in taking split second decisions and debating to go or stop. You could have a blown tire and take out the squat switch which would prevent t/r, ground spoilers, ect from being utilized. It prevents the risk of running off the end or departing the side of the runway. What is the harm of just taking it in the air? She will Fly, If you are within your weight limitations. On Shorter runways 5000 or less 90 knots is my abort speed. Anything after I take it in the air. But once again, I guess until we are in the situation, thats how the story goes..

Unless your VR is 100 kts, if you lose an engine at 95 kts, you may not have the runway to take it in the air, especially if you're operating at or near a BFL condition. Otherwise, I agree with everything else you wrote.

 

[NCherches]

You've overlooked nothing....but you are applying common sense and critical thinking to a situation.

Doing that removes you from the "train like you fly, fly like you train" mindset and could possibly cause you issues if you hesitate on a runway that is shorter.

If I bang an engine at V1 1/4 down a long runway, I know I'll have PLENTY of runway to return to for a OEI approach and landing...and I'll take those odds over the proven higher risk from a high-speed RTO any day.

Exactly... I have been known to increase my V1 to my VR speed at airports with 10K runways but NEVER reduce your V1 because of Ice, short runways, etc... I have seen guys do that too many times!

 

[Basil]

...NEVER reduce your V1 because of Ice, ..!

What's your rationale behind NEVER reducing V1 on an ice covered runway? Seems to me that an icey runway is the BEST time to reduce V1.

 

[con-pilot]

Hmm...Falcon..Airbus...

Add the Boeing 727 to that list, V-1/V-R is the same on nearly all takeoffs.

PNF call is, "V-one, rotate."

 

[hobbsmeter]

What's your rationale behind NEVER reducing V1 on an ice covered runway? Seems to me that an icey runway is the BEST time to reduce V1.

Agreed!
A snowy/slushy/icy runway is when you WANT to reduce V1, as to make the "GO" decision earlier in the takeoff roll.
You might not be able to stop on the remaining slippery runway if you abort with no adjustment to V1.

 

[semperfido]

Agreed!
A snowy/slushy/icy runway is when you WANT to reduce V1, as to make the "GO" decision earlier in the takeoff roll.
You might not be able to stop on the remaining slippery runway if you abort with no adjustment to V1.

I agree. I too, would reduce to V1min on critical runway situations.

 

[Hugh Johnson]

This a great general review, with lots of pictures and big type! Doesn't really answer the thread questions but is on topic.

selair.selkirk.ca/Training/systems/power-point/AVIA%20240/04V-speeds.ppt

 

[Hugh Johnson]

This is a great article! Actually approved data!

 

[Thedude]

NEVER reduce your V1 because of Ice, short runways, etc... I have seen guys do that too many times!

No, you want to reduce your V1 on a contaminated runway. Takes more distance to speed up to V1 and may take more to slow down.
IF I had a short runway, that is excalty when I would want to reduce V1.

 

[NGT]

Wow your rotation and single engine climb speed are the same? I have never heard of that.

3-1=2. Single Engine failure in 50/900 is an Abnormal not an Emergency. Falcon list VR = V2 in performance data and recommends holding whatever speed is reached with normal rotation speed. If failure occurs at speed higher that V2(VR+rotation) maintain that speed.

 

[SDCFI]

No, you want to reduce your V1 on a contaminated runway. Takes more distance to speed up to V1 and may take more to slow down.
IF I had a short runway, that is excalty when I would want to reduce V1.

Yes, but only if the Flight Manual has data that accounts for the reduced V1. If you tank an engine at the lower V1 you may not have enough thrust to accelerate to VR on a contaminated surface. It sounds like some people are saying they arbitrarily adjust V1/VR depending on the conditions of the day, that is no different then aborting past V1, either way you're now a test pilot.

 

[GCAP]

Performance calculations for the Boeings produce a recuced v1 for long runways. I remember many times trying to explain this to other pilots when departing 31L at JFK (14,572') The long runway allows more time (runway) to accelerate to VR and clear obstacles.