Turns Within the Airport Boundry

[no sig]

The B738 flight I was on the other night, took off from a major middle-east airport; gear up, maybe 5 secs later and through a guess at 600 feet, he executed a 90 degree turn on course well within the airfield boundry and before the end of the runway, we ended up crossing a paralell runway mid-way. I was alway taught, no turns within the airfeild boundry, putting aside take off performance, obstacle issues. Seems to me this was a bit of cowboy manoeuvre, or is known to happen?. Appreciate a view on the matter.

[Daysleeper]

maybe a threat on the normal departure track? or alternatively if the airfield is big enough to get to 600 ft while still within the boundary, it's not really an issue.

[Spitoon]

No blanket ban on turns within the boundary that I can think of. No turn below 500ft is a common operating practice, I believe. May have been a 'early turn' request from ATC for some reason - quite often enjoyed by crews in my experience!

[Quintilian]

At my (rather small) airfield the 737 does it all the time during visual climbouts. At least a few times a day under CAVOK-conditions I will see one executing the maneuver at approx 500 ft (last year some wacko did it significantly lower than that, my guess being at 250-300 ft).

[HEATHROW DIRECTOR]

<<I was alway taught, no turns within the airfield boundry>>

I've read that some place else, but never in official documents. I've turned aircraft off SIDs well within the airfield boundary.... and had aircraft ask to do so to avoid CB, etc. Hot jets can get to 6000 ft by the airfield boundary with a long runway. Can't see any problem.

[no sig]

Well I suppose this departure wasn't so strange after all then- and this was a very large airport and long runways- and easy to get to a safe height well before the end of the runway- so maybe not an issue. Anyway, thanks to you all for the response.

[DFC]

Generally, the absolute minimum height for starting a turn is 394ft (120m). It is assumed that the earliest point at which this height will be reached is 600m from the start of the runway.

Therefore (unless specified otherwise) it is entirely possible to commence a turn at 394ft, 600m from the start of the runway and comply with the obstacle clearance criteria.

Where the procedure designer wants to eliminate the posibility of an early turn i.e. wishes to avoid some obstacles then they can specify that no turns are made before the departure end of the runway.

All of the above of course depend on all engines operating.

One engine inop can have turns specified as starting when as little as 50ft net obstacle clearance is acheived.

[no sig]

Thanks DFC, this is getting at what I was concerned about, although I couldn't have explained it as well as you have. However, in fairness to this pilot, I do think we were above 400' when he commenced the turn, and the tall Tower was a ways off.