Ek B747f Rto Ams
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Ek B747f Rto Ams
http://www.airliners.net/open.file/588609/L/
Rather interesting viewing the comments on the above file, couldn't find any info in Pprune on this but would like to be enlightened if anyone has any info.
Rather interesting viewing the comments on the above file, couldn't find any info in Pprune on this but would like to be enlightened if anyone has any info.
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There was also some interest in the number four engine in a related discussion on a-net, as it does not appear to be rotating, although it's possible that it had a spiral spinner, where the others may not have and thus created this illusion.
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Strange one. The nosewheels appear to be giving off a lot of smoke and are hard over to the left. If it is a T/O attempt, given the position of the nosewheel, why are the rudders hard over left? I suspect this may be turning off the runway with rudder nosewheel steering and the tiller being used. If the circumstances described apply, I'd have thought far more engineering inspection was needed.
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No insight into the incident but did find it a bit strange that, according to the comments attached to the picture, they had an off-set nose-wheel, rejected the take-off, somehow got the nosewheels pointing the right way and then blasted-off again. Sure 2300 meters is plenty if it's not heavy but going purely on what the photographer has noted it seems odd that they didn't accomplish a greater level of inspection than having the fire-brigade look at the nosewheel.
4HP
4HP
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Interesting note there James, maybe this was a three engine ferry flight with quite some directional control difficulties. This would account for full left rudder and nose wheel hard left as well, if the yaw on the t/o roll had been significant, and drew them closer and a bit quick to the side of the runway, then certainly full left rudder and if the speed is still low enough, a good handfull of tiller, which it looks to be have been the case here. Pure guessing here, but intrigued about this.
Thinking again though, if it was a three engine ferry flight, I certain would have thought they would have opted for a back track and full length departure.
Thinking again though, if it was a three engine ferry flight, I certain would have thought they would have opted for a back track and full length departure.
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I really do not have any clue about ferry flights.
However, this kind of procedures is not daily stuff.
I can imagine that in this case it to be reasonable to assume one may want to practice a semi aborted take off in case the real thing happens in order to get some feel for it.
Seems to me that they may have planned the whole thing in advance, just a thought, nothing more.
However, this kind of procedures is not daily stuff.
I can imagine that in this case it to be reasonable to assume one may want to practice a semi aborted take off in case the real thing happens in order to get some feel for it.
Seems to me that they may have planned the whole thing in advance, just a thought, nothing more.
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The nosewheels appear to be giving off a lot of smoke and are hard over to the left. If it is a T/O attempt, given the position of the nosewheel, why are the rudders hard over left? I suspect this may be turning off the runway with rudder nosewheel steering and the tiller being used.
Other possibility is that the initial takeoff was aborted because the steering was not centered and the Body Gear Steering warning came on when the engines were spooled up. Combination of light airplane, using brakes to try to steer, and non-centered tiller steering could scrub the nose tires...
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Folks,
just like to draw your attention to number4 engine on the picture, as from picture taking vantage point only, this one does not seem to "running at full power" - looks more like "windmilling along"... check the other engines and there seems to be more motion noticeable
Again, this only by looking at the picture.. either the gentleman that took the picture has a "split shutter possibility" on his cam or my eyes are getting old.
Cheers
just like to draw your attention to number4 engine on the picture, as from picture taking vantage point only, this one does not seem to "running at full power" - looks more like "windmilling along"... check the other engines and there seems to be more motion noticeable
Again, this only by looking at the picture.. either the gentleman that took the picture has a "split shutter possibility" on his cam or my eyes are getting old.
Cheers
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First point, note the "V4" board at the bottom left. The aircraft is therefore on or near the threshold of 36L. There are no turn-offs to the left (towards the photographer) on this runway.
A 3 engine ferry t/o might seem plausable but I thought that it was SOP to remove the fan blades from the dud engine on the 747. they still seem to be in place?
A 3 engine ferry t/o might seem plausable but I thought that it was SOP to remove the fan blades from the dud engine on the 747. they still seem to be in place?
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To me the picture looks like a 3-ENG Ferry T/O. I am not saying it IS a 3eng ferry T/O, I'm saying I THINK it is one.
OK, when doing a 3eng ferry T/O, you have to stick to the procedures. I don't know 744's, but on the A/C I flew, the two (opposite) symmetrical engines had to be set to T/O thrust with the 3rd at 50% N1. Once 70kts was reached (dependant on wet R/W or not) the 3rd engine was brought to T/O thrust.
When you initiate the T/O roll it is best to keep full rudder and gently let it ease off as the speed increases. But when the 3rd engine's thrust is set, another rudder input has to be made to keep centreline. Any other method of setting thrust saw you off the runway.
So, if you set T/O thrust before brake release and then you let rip with three engines, you'll be standing on the rudder pedal (2engine side) & probably grip the tiller to assist and immediately bring the thrust levers to idle and wipe the sweat of your face.
Luckily I don't have that experience yet
OK, when doing a 3eng ferry T/O, you have to stick to the procedures. I don't know 744's, but on the A/C I flew, the two (opposite) symmetrical engines had to be set to T/O thrust with the 3rd at 50% N1. Once 70kts was reached (dependant on wet R/W or not) the 3rd engine was brought to T/O thrust.
When you initiate the T/O roll it is best to keep full rudder and gently let it ease off as the speed increases. But when the 3rd engine's thrust is set, another rudder input has to be made to keep centreline. Any other method of setting thrust saw you off the runway.
So, if you set T/O thrust before brake release and then you let rip with three engines, you'll be standing on the rudder pedal (2engine side) & probably grip the tiller to assist and immediately bring the thrust levers to idle and wipe the sweat of your face.
Luckily I don't have that experience yet
Possible No 4 engine explanation is that all 4 engines are pulled back to idle after reverser stowage in an RTO.
If No 4 was a recently replaced engine it would have a freshly painted nose spinner spiral and there would be little blurring at idle.
The other engines could have been on wing long enough to erode away the spinner paint.
I'm not sure that this is the explanation for this photo since other scenarios could apply, e.g. # 4 brought to idle to control yaw while others left at higher power.
Of course I don't have a suitable explanation for why the reversers are not seen to be deployed at this point.
Just a interesting fun puzzle seeing how mixed up you can get trying to read a photo.
If No 4 was a recently replaced engine it would have a freshly painted nose spinner spiral and there would be little blurring at idle.
The other engines could have been on wing long enough to erode away the spinner paint.
I'm not sure that this is the explanation for this photo since other scenarios could apply, e.g. # 4 brought to idle to control yaw while others left at higher power.
Of course I don't have a suitable explanation for why the reversers are not seen to be deployed at this point.
Just a interesting fun puzzle seeing how mixed up you can get trying to read a photo.
Title? What title?
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Non pro comment here.
Intriguing picture . If you click on the registration, there are other shots of the aircraft including the aftermath which shows a straight nosewheel and a comment that the aircraft was cleared by the tower (for take off?). If this occured at any great speed, wouldn't there be serious damage to the nosegear which appears to be at 90 degrees to direction of travel.
(Edited to ensure what I meant was expressed)
Intriguing picture . If you click on the registration, there are other shots of the aircraft including the aftermath which shows a straight nosewheel and a comment that the aircraft was cleared by the tower (for take off?). If this occured at any great speed, wouldn't there be serious damage to the nosegear which appears to be at 90 degrees to direction of travel.
(Edited to ensure what I meant was expressed)
Last edited by phnuff; 1st Jun 2004 at 16:38.
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Well i thought id add that max nose gear angle on the 747-400 is 70 degrees by the tiller and 7 degrees from pedel steering.
That looks like max left tiller input! which is 150 degrees of tiller rotation, eh??? why the pilot would be winding the the tiller that much at this point is puzzling.
Very strange one that.
Stu.
CAA Eng.
That looks like max left tiller input! which is 150 degrees of tiller rotation, eh??? why the pilot would be winding the the tiller that much at this point is puzzling.
Very strange one that.
Stu.
CAA Eng.
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Thanks for that. We used to do the same on the 146.
Note however that the fan/spinner is in a different position in the photo with the fire engine - approx 90degrees difference.
Maybe it was supposed to be a normal t/o and #4 was (very) slow to spool up thus giving the swing?
Note however that the fan/spinner is in a different position in the photo with the fire engine - approx 90degrees difference.
Maybe it was supposed to be a normal t/o and #4 was (very) slow to spool up thus giving the swing?
