View Full Version : What is a 777-200 Vref speed at a typical landing weight?


StratMatt777
3rd May 2010, 05:08
I am a flight instructor and flight sim nerd and am gonna bother you guys with my question because I cannot find it anywhere on the internet...
I would love to know what the Vref30 approach speed is for a 777-200 and/or 200 ER at an average landing weight.
It seems that the maximum landing weight of the 200ER can be as high as 470,000 lbs...

If any 777 drivers see this and would be so kind, what is an example of an average weight you often land at and the associated Vref speed?

If you could give me speeds for a couple weights (I know you guys don't memorize this stuff!) so I could interpolate that would be even better. :)

Here is a very interesting Boeing article about choosing whether or not to make an overweight landing in an emergency: http://www.boeing.com/commercial/aeromagazine/articles/qtr_3_07/AERO_Q307_article3.pdf
page four has a graph with abnormal Vref speeds for 767-300ER, MD-11, 777-200ER and 747-400 for use with landing weights in excess of MLW.

Since the airlines aren't hiring (not even 135 freight) I'm passing time with flight sim (and some VERY part-time flight instruction)!

Can anyone here tell me Vref at a typical weight (or more)?



Thank you!! :)

Matt in Jet City (Seattle, WA, USA)
1287/265 multi :)



eckhard
5th May 2010, 12:51
Sorry for the formatting, but I think you can read this OK:

B.777-200 GE90-76B

Vref (kts)

WEIGHT
(1000) FLAPS
LBS KGS 30 25 20
550 250 151 159 164
528 240 148 156 161
506 230 145 152 158
484 220 142 149 154
462 210 139 145 150
440 200 135 142 147
418 190 132 138 143
396 180 128 134 139
374 170 124 131 135
352 160 121 127 131
330 150 117 123 127
308 140 113 118 123


Hope this is what you need.

If you like, PM me with your email address and I'll attach the actual table which will be easier to read.

Happy simming!

regards,

Eckhard

Old Smokey
6th May 2010, 07:34
A very nice answer by eckhard:ok:

As the original question asked for a "typical" Vref, Boeing use a default figure of 130 KIAS for FMC purposes, until modified by the pilot. I'm not going to argue with Boeing for what they consider a "typical" figure.

No need to interpolate, for the normal Flaps 30 Vref, using Metric Tonnes for weight, apply the following formula -

Vref30 = SQR(Landing Weight in Tonnes / 250) X 151

Regards,

Old Smokey

MrBernoulli
6th May 2010, 11:35
Old Smokey, that is a nice little formula there - thanks for that! Stuff like that is useful to tuck away for future use.

Do you have something similar for the 777-300 too? We start receiving our new airframes this year.