I will calculate your Q400 v-speeds for you here!

Hi guys, just thought I’d put something out there. :) I got my hands on a performance calculator for the Dash-8 Q400, to get accurate readouts of V1, VR, V2, VFRI, VCLIMB and takeoff torque %. If you want those I can calulate them for you, just comment these specs:

– Airport ICAO code
– Departure runway
– Flap settings (should be flap 5 or 15)
– Surface wind
– OAT (Outside Air Temperature)
– QNH
– Takeoff weight
For example, comment something like this: “ENGM, 01L, flaps 5, 350/12, 6 degrees, 1016, 2924kgs”

To elaborate on the speeds:

V1

The speed beyond which the takeoff should no longer be aborted.

Vr

Rotation speed

V2

Takeoff safety speed. The speed at which the aircraft may safely be climbed with one engine inoperative.

VFRI

Flap Retraction Initiation. The speed you have to be above before retracting flaps (Q400’s often just go straight from flap 15 to flap 0, no need to go via the other ones)

VCLIMB

Max performance / recommended climb speed

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ENZV, 36, Flaps 15, 319/6, 5 degrees C, 1013, 27578 kg

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YMRY - 36 - 15° - 00000kts - 16°C - 7 - 27,166kgs

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Do you need new batteries for that calculator? 😅Jk

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Thank you for this, when i fly the Dash, ill see if I can ask here.

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V1: 115 KT
Vr: 115 KT
V2: 116 KT

VFRI: 129 KT

VCLIMB: 153 KT

(V1 and Vr is the same, which basically means you have V1. You can still safely stop on the runway at rotation speed)

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I need the QNH as well!

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Wouldn’t it be easier if you shared the link? :)

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It’s not a free nor publically open performance calculator I’m afraid – hence why I made this. :)

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Ok, cool :) thanks for supplying us with it then :-)

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But using the current QNH for YMRY I got this. :)

(I would not recommend using flap 5 for this as you would only be left with a 40m margin. I have used flap 15 for this, as this is also a more common flap config)

V1: 115 KT
Vr: 115 KT
V2: 116 KT

VFRI: 128 KT
VCLIMB: 151 KT

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Did I put flap 5? Oh ok, you are right tho, I meant 15 :)

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I wouldn’t have dared a 40m margin hahaha, I would need an extra set of underwear if so… :P

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Hey dude,

I got excited at the prospect of having a calculator then! Shame if it can’t be pushed to the wider audience!!

I’ve altered your title slightly, to manage folks expectations seems my day has been completely ruined (I’m joking) by the travesty that I can’t calculate these figures for myself.

Per Ardua!

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Thanks, great stuff!
What about power setting? Not the same value in IF? In the Q400 I usually use 80-85% on take off.

Power settings in this is NTOP (Normal Take Off Power). :) That’s 90% torque. :)

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KEWB, runway 14, flaps 15, winds calm, 15 degrees C, 1013 hpa; 30,480 kg.

V1: 120 KT
Vr: 120 KT
V2: 120 KT

VFRI: 132 KT

VCLIMB: 157 KT

(V1 and Vr is the same, which basically means you have V1. You can still safely stop on the runway at rotation speed)

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To clarify a little bit after some questions – IF hasn’t got an option for displaying torque. But you can get a rough estimate using the V1 % (green percentage over the throttle). NTOP is ~90%, so you can use that for your takeoff power. :)

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