Questions to wide-body drivers

[hamil]

Hi folks,
When taxing a wide-body airplane using the runway (width: 45m) as a taxiway how do you make an 180-degree turn to align the airplane prior to takeoff? Considering there’s a small adjacent turning area beside the runway threshold, for instance on your left, do you make an initial turn to that area and then a right turn to runway alignment or taxi close to the right runway lateral limit and then make a constant left turn in direction to turning area until reaching the runway alignment?
Thanks.

[None]

I would prefer to put the edge of the hard surface on my side, so in your example I would prefer to taxi left into the expanded turning area, and then make the maneuver to line-up to the right. This allows me to see with my own eyes how the turn is progressing. Mumbai runway 27 is our only destination which regularly requires the 180 on the runway prior to takeoff.

[Captain Airclues]

hamil

In general, you should align the aircraft parallel to the straight side and then turn towards the turning pad. If you go into the pad first then you risk dragging the main gear across the corner of the pad. The are a few exceptions where this would cause blast damage but in these cases there are clear taxiway markings and the pad corners have been extended (Islamabad is one such case). Mumbai can be confusing as there are narrow turning pads on both sides at the 27 threshold, but they are long enough to avoid problems with the main gear.
The absolute minimum turning circle for a B747-400 (assuming you get everything right) is 46.6m.

Airclues

[None]

A good point, and certainly something to consider. My recollection of Mumbai is that the turning area was long enough to fit the entire length of the jet into the area before executing the turn....but I could be wrong, being that it is usually 0200. At last look, it appears they are serious about extending the taxiway all the way out to the approach end of 27.

[GlueBall]

After a 180 degree turn on the runway, I don't waste pavement to realign on the centerline for takeoff, I start rolling from whatever side of the runway the turn was completed.