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747 rotates way down the runway

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Very cool

Thats not an illusion, that was a close one. Caution wake turbulence! Great video thanks for the link.
 
We were taking off out of Gander one day. The tower told the guys working at the end of the runway that a Heavy 747 was taking off. The construction guys said 'go ahead, we will be alright". We started our takeoff, once we crossed the hump in the middle of the runway we could see the workers and tractor down at the end. Our takeoff was just like the one in that video. When we got just beyond 4/5 down the runway there were workers and tractors running everywhere. It had to have been f'n loud when we went over. I bet they moved next time a heavy took off.

CJ610
 
That's normal. Sometimes jets stay on the runway longer to accelerate for gusting winds or something. I'm sure the 747's V1 speed was attained about halfway down that runway. It's just easier to accelerate down a runway than it is to acceleratee during climb out. Extra speed is good when the winds are crazy.
 
Mmmmmm Burritos said:
That's normal. Sometimes jets stay on the runway longer to accelerate for gusting winds or something. I'm sure the 747's V1 speed was attained about halfway down that runway. It's just easier to accelerate down a runway than it is to acceleratee during climb out. Extra speed is good when the winds are crazy.

What the hell is in your burrito....Crack?
 
It's true. It's in our company's POH and in training to do that when you have suspected windshear on takeoff. If you rotate at Vr and suddenly get a loss of 30 kts airspeed due to windshear, you're pretty much screwed. But if you stayed on the runway and accelerated 20 kts or so past V1 then you'll probably be fine. That's of course if there isn't much terrain in front of you to climb over.

Of course in that video we have no idea what they're really doing.
 
Total normal takeoff

Looks completely normal for a widebody four engine airplane. In fact I would suggest that seeing it leave the ground it is probably well below both gross weight and numbers for that particular runway. I'm with the other guy what kind of crack is in your burrito.
 
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He was probably on speed, From the time you start to rotate a 747 and when the mains actually leave the runway is in the neighborhood of 2000 feet or so. When heavy on that puppy you do not have the luxury to wait a bit longer, most of the time it's Vr or the end of the runway....whichever comes first! :)

Get it heavy enough and there can be enough time between between V1 and VR to hold a short conversation about politics or whatever.......not that you do since that would violate the sterile cockpit!!:D
 
I think I know what Burritos is talking about. It's an old rule of thumb-type thing that if you are taking off into suspected windshear, you bump your speeds up to the max speed for the runway restriction weight. So lets say your airplane weights 200,000 lbs, and your runway restriction/climb restriction is 300,000 lbs, you use speeds for 300,000 lbs (or your max takeoff weight if it's lower). You also use the maximum thrust setting available (no thrust reduction). Then you'll rotate a little farther down the runway, at a higher speed. Now, you also can climb at a lower deck angle should obstacle clearance allow. This extra speed above Vs will provide you with some potential energy, which can be transfered into kinetic energy should you encounter windshear.

Can't say I follow this rule myself, but I have read and hear about this from some older pilots. Makes some sense I'd say. If you are going to experience windshear, would you rather have a 1.3 margin above Vs, or a 1.5+ margin above Vs?

Check out the windshear section of "Fly the Wing" by Jim Webb.
 

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