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Driver170

High winds takeoff

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Took off from EDDF rwy 25L with heavy head winds 35 kts and i'm using ASN.

 

during the takeoff roll i noticed my GS was way higher than my IAS what input should i take? professional feed back please :)


Also i'll add in - check the general instructions for EDDF for navigraph it said climb at V2 + 10 how do i change it from V2 + 20 on the NGX....

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Heavy headwinds and then higher groundspeed than airspeed. Sounds like a microburst. I am guessing you had some thunderstorms over you. ;)

 

 If below V1 and you feel the take off is unsafe. Abort.

 

If above V1 and feel the take off is unsafe. Pray.  

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First of all - how is your GS HIGHER than your IAS when you have a headwing of approx. 35 knots? This might be an indication of a windshear that results in a sudden tailwind on takeoff which is quite dangerous, 

 

The general procedure for crosswind takeoffs is to move the aileron into the wind at the begining of the takeoff and gradually ease off that input to compensate for the increased pressure on that wing as you are gaining speed later during the takeoff roll. As soon as you are airborne kick the rudder and point the nose into the wind in order to maintain the runway heading - just like on a crosswind approach (but the other way around, really).

 

Regarding your last question, which I don't understand - what do you mean by 'change it on the NGX'? 

You calculate your V2 speed taking various factors into account, such as runway condition, wind portion, engine rating, your takeoff weight etc... If the climbout procedure tells you to add 10 or 20 knots to that speed you simply add those 10 or 20 knots to your V2 speed and set this particular speed on the MCP as you climb out.

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Yes thunderstorms and windshear in the area!

 

I kept her on the centre line but after i reached 100 kts both speeds matched again takeoff was kinda smooth and engaged CMD A at 1500 AGL.

 

Well my V2 was 148 and the systems commands an extra 20 kts to it so i'm in the air at 168 kts till acc height 3000 AGL

 

Just not sure how to change it to +10

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Also during roll N1 was set for 88.3 but it advance automatically to 91 or something

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Read the FCTM for crosswind takeoff. There is no rudder kicking.

 

Don't monkey with the V2+20.

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Read the FCTM for crosswind takeoff. There is no rudder kicking.

 

Don't monkey with the V2+20.

 

Yeah the FCTM is the source for those procedures - I should not have said "kick the rudder" it's just what works in the sim at least with my clunky hardware haha.

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Read the FCTM for crosswind takeoff. There is no rudder kicking.

 

Don't monkey with the V2+20.

 

but EDDF instructed takeoff v2 + 10 how do i change it to that instead of the default 20

 

Took off from EDDF rwy 25L with heavy head winds 35 kts and i'm using ASN.

 

during the takeoff roll i noticed my GS was way higher than my IAS what input should i take? professional feed back please :)

Also i'll add in - check the general instructions for EDDF for navigraph it said climb at V2 + 10 how do i change it from V2 + 20 on the NGX....

 

 

SORRY it was my IAS that was higher my V1 was 144 but my GS was way lower like 110 kts is this still ok to take off and what speeds am i going by ? GS OR IAS

 

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but EDDF instructed takeoff v2 + 10 how do i change it to that instead of the default 20

Why would the airport issue such procedures is what I want to know.

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Why would the airport issue such procedures is what I want to know.

 

Well, it's noise abatement. 

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Well, it's noise abatement. 

Hmm....never heard of a noise abatement procedure that did that. Interesting.

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Its in black and white.

 

Now can anyone answer my question lol how do i set it at v2 + 10

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Hmm....never heard of a noise abatement procedure that did that. Interesting.

 

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On navigraph STAR charts for engine failure you have a box some say NON STD and STD for engine failure what are these?

 

Also MNM CLIMB GRADIENT 6.6 % to 5000 what is the calculation for that guys?

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See SID 25L/C MARUN 3F/3J TOBAK 4f/4J: Climb gradient 12 % to D8.4 FFM.

 

This means you have to climb 12 % in altitude for the distance of 8.4 nautical miles from FFM. 

 

12 % of 8.4 is 1 nautical mile. 1 NM = 6074 ft.

 

If you have a ground speed of say 180 knots on climb out you cover 8.4 nautical miles in 2.8 minutes

 

In that time you need to climb 1 mile. Again 1 NM = 6074 ft.

 

6074 ft / 2.8 min = 2169 ft / min.

 

So basically 180 knots ground speed on climbout requires rate of climb of more than 2169 ft/min to make the profile set in the SID. 

 

 

The easy way to calculate it in the cockpit is to multiply your ground speed with the % gradient:

 

12 % gradient x GS180 = 2160 ft/min

 

7 % gradient x GS180 = 1260 ft/min

 

5 % gradient x GS160 = 800 ft/min

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Where did you get that 2.8 min from?

 

Thanks for the sum dude :)

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Where did you get that 2.8 min from?

 

If you have a ground speed of say 180 knots on climb out you cover 8.4 nautical miles in 2.8 minutes. Now, the 180 knots is just an example. 

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Yeh but how do you do the maths 180 kts in 8.4 nm ?

 

My maths sucks dude being honest here lol

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Yeh but how do you do the maths 180 kts in 8.4 nm ?

 

My maths sucks dude being honest here lol

Knots is simply nautical miles per hour, so you take 8.4, divide it by 180 knots, and that gives you the time to travel that distance in hours. Multiply by 60 and you get 2.8 minutes.

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But do we actually need to do this for the 737 as the FMC will do this when in VNAV?

 

 

How about 7.4 % for 4500 i got 2,300 fpm and climbing out at 168 knots?

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How about 7.4 % for 4500 i got 2,300 fpm and climbing out at 168 knots?

 

Then it is as follows: (7.4 x 168) ft/min = 1243,2 ft / min required. So you are good to go.  ^_^

 

Remember every time you get a climb gradient, just multiply that factor to your ground speed. That will give you your required rate of climb.

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Is this something real pilots do even if they are using a sid and VNAV?

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