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Vspeeds Not available?

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During my flight KORD-OPKC I had 90% Fuel full load of PAX so set F20 due to the TOW, as soon as I entered the RW for take off, in the FMC, I get the "Vspeeds Not available" msg, I have programmed the FMC a million times, CG in there, Gross Weight, trimmed etc etc.. so tried diff flaps settings still the FMC wouldn't display the V Speeds. Lucky I needed F20 took the whole runway to takeoff. :)

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What runway did you try taking off from. If you took the whole runway up for take-off, you probably shouldn't have taken off from that runway in the first place.

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Vspeeds Not available

 

Basically, the FMC is saying "given the information you've provided, I can't (or won't) provide you VSpeeds."  In your case, it was the latter:

 

"Based on the information your provided, there's no safe way for you to get out on that runway."

 

Evidence?  Your whole-runway takeoff...

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32R is 10,005 feet long according to wikipedia. Obviously they aren't the best source but they usually provide accurate information about the airports. I thought 10,000 feet was enough for any plane. I suppose depending on flight length, etc. that may not always be the case.

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32R I think, oh so it's the RW length wasnt sufficient. Keep that in mind for next time. Was in a rush to get going so didn't check the RW length. Oops

According to the charts, runway 32 right is only 10,005 feet long. At that weight, I think it's safe to say you were too heavy to be able to make the take-off safely. Also don't know what thrust rating you used, so a derate wouldn't have been a good idea. Aviation is not something where you really want to be rushing. Had you been using runway 32 left or 4 left for some reason, those runways are even shorter, you would have gone right off the runway, so it's best to check these things before you go.

 

32R is 10,005 feet long according to wikipedia. Obviously they aren't the best source but they usually provide accurate information about the airports. I thought 10,000 feet was enough for any plane. I suppose depending on flight length, etc. that may not always be the case.

There's a lot of factors you have to consider, such as take-off weight, runway length, temperature, and take-off thrust are the few I can think of off the top of my head. Also, if you have any MEL items that put any restrictions on the aircraft operations.

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According to the charts, runway 32 right is only 10,005 feet long. At that weight, I think it's safe to say you were too heavy to be able to make the take-off safely. Also don't know what thrust rating you used, so a derate wouldn't have been a good idea. Aviation is not something where you really want to be rushing. Had you been using runway 32 left or 4 left for some reason, those runways are even shorter, you would have gone right off the runway, so it's best to check these things before you go.

I rotated at about 170knts, she WAS airborne before the end of the runway, no tailstrike msg and had logging software as this was a VA fight. Just gotta takeoff from the ATC designated runway next time and take my time . I also derated the takeoff, schoolboy errors, but the virtual pax got there in one piece lol.

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I rotated at about 170knts, she WAS airborne before the end of the runway, no tailstrike msg and had logging software as this was a VA fight. Just gotta takeoff from the ATC designated runway next time and take my time . I also derated the takeoff, schoolboy errors, but the virtual pax got there in one piece lol.

Yes, but when you're at the point where you're taking up the entire runway, there's a problem. With a runway of that length, a derate made your situation worse. If you did a full-thrust take-off, you might have been able to conduct the take-off in a safer manner. Obviously nothing you can do now (except hope the virtual FAA doesn't come knocking on your door), but now you know for next time.

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You should be taking off full length runway 28R

 

I have this message sometimes, after calculating TOPCAT profile it gives me the wrong data, like TO2 55c and the FMC did not like it. So I change to TO1 and it worked.

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According to the charts, runway 32 right is only 10,005 feet long. At that weight, I think it's safe to say you were too heavy to be able to make the take-off safely. Also don't know what thrust rating you used, so a derate wouldn't have been a good idea. Aviation is not something where you really want to be rushing. Had you been using runway 32 left or 4 left for some reason, those runways are even shorter, you would have gone right off the runway, so it's best to check these things before you go.

 
 

There's a lot of factors you have to consider, such as take-off weight, runway length, temperature, and take-off thrust are the few I can think of off the top of my head. Also, if you have any MEL items that put any restrictions on the aircraft operations.

 

Okay, after I posted that I figured 10,000 isn't that much for such a long flight with such a high load. Obviously temperature and thrust had to play a part as well. Thanks for clarifying for me!

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Jeremy, altitude of airport plays a significant role as well my friend ;)

 

Very true - I'd love to see a 777 make it off of the 9,000 foot runway at Eagle/Vail Airport in Colorado. OH did I forget to mention it's at 6,547 feet ASL?  :P

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Very true - I'd love to see a 777 make it off of the 9,000 foot runway at Eagle/Vail Airport in Colorado. OH did I forget to mention it's at 6,547 feet ASL?  :P

At lower weights it probably could. 

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Very true - I'd love to see a 777 make it off of the 9,000 foot runway at Eagle/Vail Airport in Colorado. OH did I forget to mention it's at 6,547 feet ASL?  :P

Don't forget you have El Alto at over 13,000 feet in altitude.

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I rotated at about 170knts, she WAS airborne before the end of the runway

 

 Vspeeds are calculated on single engine performance. V2 is the minimum speed that must be reached before 35ft with one engine inoperative, this is for obstacle clearance.  Your takeoff may have been successful with both engines running, in the real world you plan for an engine failure :)

 

Something else to consider is your ability to stop. The aircraft may be able to become airborne on a particular runway, however take off is not authorized because sufficient runway length does not exist to abort at the calculated V1

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