Question for a BA pilot re LAX takeoffs

[BrightonGirl]

At LAX yesterday, in the late afternoon, I watched a BA flight take off for LHR. All LAX takeoffs are east to west, so I expected it to turn north -- I had always assumed that all flights to northern Europe did that. But instead, it turned about 30 degrees south and as it flew out of sight was heading southwest.

Why? How far southwest over the Pacific would it have gone before turning back?

(Hope this isn't a really dumb question!)

[Captain Airclues]

Brightongirl

It is a couple of years since I have been to LAX but will do my best to answer.
Most departures to Europe turn to the south after take-off. I believe that this is to avoid conflicting with inbound traffic from the north. If departing from the southern runways (25R) then they will initially fly a heading of 250 and then turn onto a heading of 220 when passing the SMO (santa Monica) 160 radial. If departing from the northern runways (24L) they will head 250 until the controller tells them to turn left, generally onto a heading of about 220.
When the controller is satisfied that they have sufficient height, he will turn them left towards Seal Beach VOR. After Seal Beach they will turn left towards another VOR such as Daggett and then they proceed on course.
The distance that they fly out over the Pacific depends on how well they are climbing as they must be at about 14,000ft on reaching Seal Beach so that they pass over the inbound traffic to 24R and 25L.
Hope this helps.

Airclues

[Avman]

On a recent departure from LAX to AMS/SPL, off 24L, we maintained runway heading for about 10 miles, followed by a left turn of about 20 degrees for another 10-15 miles, followed by a left turn back to the LAX VOR. We then continued North abeam Ontario, South abeam Victorville and overhead Las Vegas in a general ENE direction.

[BBK]

BrightonGirl

It's not a dumb question at all. Just adding to the guys who have already answered they are right in that there are altitudes to be met. If I recall 10,000' at LAX etc on the Daggett transition and 14,000' for a SID via Seal Beach. Hence you need to fly out over the sea to gain sufficient height before turning eastbound.

It's also worth remembering that the SSA in this region is about 13.5 'cos of the bloody great mountains! Hope this helps.:D

[West Coast]

As a follow on, runway 25L is the longest runway at LAX at 12091 ft long. Don't know about the departure you saw but at times performance requirements dictate its use even if it heads you in the wrong direction initially. Lax doesn't like to cross departures from the 24 and 25 complexes. If you depart the northern runways(24's) you generally go straight out or make a right turn twords the north. If you depart the south runways (25's) you generally make a turn to the south. This is true even if its completely away from your destination. They usually have you headed in the general direction you want within a few minutes by the means others have described here.

[av8boy]

How far southwest over the Pacific would it have gone before turning back? If it went far enough, it wouldn't have to turn! :O

The SID out of LAX going to, for instance, EGLL, generally depends upon the aircraft ability to climb. If you can go up fast, you can get the Loop (out to sea until you get to the point (or well past the point, some would argue!) where you can turn left and cross the LA VOR at or above 10,000 on your way toward Vegas). However, if you can't do that, you'll probably get the LAXX. It's almost like a Loop except that the turn is wider. Instead of going six or seven miles out over the water and cranking it back around toward the airport, you make a nice easy turn around Palos Verdes before heading northeast from the LA Harbor area. Note, however, that both are left turns.

If you saw the aircraft continuing off toward the southwest, then it was probably a LAXX. Loops tend to go out of sight pretty quickly (up into the haze) and then reappear overhead a few minutes later going northeast. Also, that guess of 30 degrees left wasn't bad... off the south complex the SID calls for a 220 heading.

The reasons for the turn to the left (south) instead of the right (north) are what have been mentioned... traffic and terrain. California has LOTS of north-south traffic north of LAX, and the terrain rises rapidly there. There ARE departures that go that way (obviously) over Ventura and Gorman, but if your'e a slow climber going north out of LAX with a right turn out, expect to see some ocean. You're going to go west for a while...

Dave ;)

Edited to say saw United on the way to London get the loop, then five or ten minutes later, Virgin getting the loop, then five or ten minutes later, BA getting the LAXX. 50 miles later they were all on generally the same track.