V-speeds order

[FLT86]

Hi All,

Could you just please clarify if this V-speeds are ordered from the lower to the bigger ?

Vmcg, Vef, V1, Vmbe, Vr, Vmu, Vlof, Vmca and V2.

Thanks for your help.

[Transsonic2000]

What do you need this for, JAA exams?

Basically the sequence is correct, but if you need this for exam purpose you must bring them into context!

Sequence of Speeds:

• VMCG
• V1 (> V1 continue T/O) / V1 max = VR / V1 min = VMCG
• VS
• VMCA
• VR > V1 > 105% VMCA
• V2 > 110% VMCA / > 115% VS (if more than 3 engines) / 120% VS (2 or 3 engines)

• VREF = 1.3 Vso (jet landing configuration) / 1.23 VSR (Turbo Prop)

[FLT86]

Hi,

Thank you for your answer which helps me.

I just asked this question for my knowledge, it can be a tricky question.

Thank you !

[OhNoCB]

VREF = 1.3 Vso (jet landing configuration) / 1.23 VSR (Turbo Prop)

Pedantic, but to check my own knowledge, is this not the other way round? (ie. 1.23 VSR0 for jets?)

[AtomKraft]

Callouts:


V1.


Rotate.


Some folks like to call V2, but that's old hat these days.


Actions:


V1. Take hands off the levers.


Rotate. Pull.


Keep it simple...

[Darren999]

Call Outs

I fly a smaller jet, our call out's we use are:

Air Speed Alive
80kt cross check ( I know this stems from older aircraft)
Then V1
Rotate
V2 as a matter of course...

Seems to be reasonably standard

[mdt13]

Originally Posted by Transsonic2000

What do you need this for, JAA exams?

Basically the sequence is correct, but if you need this for exam purpose you must bring them into context!

Sequence of Speeds:

• VMCG
• V1 (> V1 continue T/O) / V1 max = VR / V1 min = VMCG
• VS
• VMCA
• VR > V1 > 105% VMCA
• V2 > 110% VMCA / > 115% VS (if more than 3 engines) / 120% VS (2 or 3 engines)

Sorry for bringing this up after so long.. but I'm preparing for interviews and this of the V speeds is something I always struggled with.. it seems to me reasonable the order of Transsonic2000 BUT in this way you must take off because you passed V1 but you haven't yet reached VS and VMCA so how can you decide to go if you are below stall speed and min. controllability?? If anyone manage to explain this to me properly I will be forever grateful!

[wiggy]

.you passed V1 but you haven't yet reached VS and VMCA so how can you decide to go if you are below stall speed and min. controllability??

In very very simple terms:.

You are above V1 so by definition you are not able to stop anymore (for whatever reason) ...however you should still be accelerating along the runway towards VR.

You are certainly committed to going aviating but you are not flying yet, you're just driving a multi tonne tricycle along the runway at increasing speed..

At VR, and not before, you rotate, and it is only at that point your aircraft actually becomes a flying machine.....

Now have another think about when VS "applies" to an aircraft and also what the "A" in VMCA stands for... hopefully that should help you understand why V1 might be less than VS and VMCA, and why in turn they have to be less than VR.

Hope that Helps.

[Alex Whittingham]

You cannot know the sequence, only parts of it. Vef, for instance (not V1) must be greater than equal to Vmcg. V1 may not be greater than Vr. Vr must be greater than or equal to 1.05 Vmca, but who is to say which is larger, Vmcg or Vmca? Who says Vs is greater than V1? No regulation. It is a basic mistake to try and run a sequence that runs Vmcg, Vef, V1, Vmca, Vr, etc... the logic doesn't follow through.

[wiggy]

Originally Posted by Alex Whittingham

You cannot know the sequence, only parts of it. Vef, for instance (not V1) must be greater than equal to Vmcg. V1 may not be greater than Vr. Vr must be greater than or equal to 1.05 Vmca, but who is to say which is larger, Vmcg or Vmca? Who says Vs is greater than V1? No regulation. It is a basic mistake to try and run a sequence that runs Vmcg, Vef, V1, Vmca, Vr, etc... the logic doesn't follow through.

Very very much agree Alex..that's why I put the "might" in why "V1 might be less than VS and VMCA."


I did start to add a paragraph to my post to the effect there was no strict sequence of speeds but deleted it since it made it too verbose, possibly wasn't going to help address the query raised by mdt13 at a suitable level, and was mindful that the front end of the thread was several years old so who knows what those posters are doing now.

As you imply it's having a grasp of the principles and what each speed means that counts.