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The Actuator
3rd Sep 2007, 22:48
Anyone who can give me a definitive answer about whether one's minimum altitude turns after take off are based on AGL or airfield elevation or runway end height? My company manual says AGL but alot of people I have spoken to say some of the other options.

reynoldsno1
3rd Sep 2007, 22:57
The design criteria normally state 120m (400ft) above the DER (Depaertuire End of Runway) elevation.

The Actuator
3rd Sep 2007, 23:06
Thanks do you have a reference for that? I would imagine that applies to the design of a SID. If it were a VFR departure at night for example and there was a hill/hole a mile from the runway then surely it makes more sense for it to be AGL?

error_401
4th Sep 2007, 00:10
If you look into PANS-OPS and the relevant ICAO documentation on IFR departures you find that the 120 m (400 feet) is the "lowest" befor any turn.
The procedure design should take into account terrain in the departure. This being the reason for different acceleration altitudes and turns or the need for specific departure routes in case of engine failures.
So the 400 feet only apply in "non obstacle limited" conditions. Try to find a Jeppesen airway manual. It should contain the references. I'm unable to access the docs at the moment so I can not be more specific.
Hope it helps a bit.

Intruder
4th Sep 2007, 01:29
FAA AIM 5-2-7 par b.1:
1. Unless specified otherwise, required obstacle clearance for all departures, including diverse, is based on the pilot crossing the departure end of the runway at least 35 feet above the departure end of runway elevation, climbing to 400 feet above the departure end of runway elevation before making the initial turn, and maintaining a minimum climb gradient of 200 feet per nautical mile (FPNM), unless required to level off by a crossing restriction, until the minimum IFR altitude. A greater climb gradient may be specified in the DP to clear obstacles or to achieve an ATC crossing restriction.

The Actuator
4th Sep 2007, 10:05
That's the stuff. Many thanks for the reply.

csd
4th Sep 2007, 10:25
When a departure route requires a turn more than 15 degrees, a turn area is constructed. Turns may be specified at an altitude/height, at a fix and at a facility. Straight flight is assumed until reaching an altitude/height of at least 120m (394 ft), or 90 m (295 ft) for helicopters, above the elevation of the DER.


DER = Departure End of the Runway


Ref: PANSOPS Volume 1 Fourth Edition Doc 8168-OPS/611 Part II - Chapter 2.3.1


Regards

csd

ZFWT
4th Sep 2007, 10:26
What about MTOW off rwy 08 honolulu with a V1 cut

PantLoad
4th Sep 2007, 12:14
Yep, this is what this forum is all about....

Now, the exceptions to this might be a published SID that dictates a turn prior to 400 feet AGL....or, an engine-out SID that dictates a turn before 400 feet AGL...or, an explicit ATC instruction, whereas the controller assumes responsibility for your climb gradient vis'-a-vis' obstacle clearance requirements.

I might add, that a generic ATC instruction to fly heading XXX after departure requires that the aircraft follow the runway heading (to the nearest degree) until 400 feet, then make the turn...as little as that turn might be.

For example, you're taking off on runway 18R...and the magnetic heading of the runway is 182 degrees. You are cleared for takeoff with the instruction that you are to fly heading 180 degrees after departure. You would fly 182 degrees until 400 feet AGL, then make a slight left turn to 180 degrees. This is the procedure in the U.S....sans explicit instructions from the controller to the contrary. I know this is being picky, but to be technically correct, this is what you would do. :ok:

Further, instructions to fly runway heading after departure (in the example cited above) would be to maintain the 182 degree heading...not the cardinal 180 degrees (the runway number). The guy off runway 18L (assuming a simultaneous departure) would do the same...and everyone would be happy...no metal touching from different aircraft. ...no matter how much crosswind.:D


Great feedback...good references...



PantLoad

Intruder
4th Sep 2007, 18:36
What about MTOW off rwy 08 honolulu with a V1 cut
08L or 08R? What about it?

First, the normal departure procedures are all about NOISE abatement. At best they are a COMPROMISE of SAFETY.

Second, where airplane performance is insufficient to follow the normal departure profile after the loss of an engine, the airline usually develops (along with Jepp or other charts supplier) an emergency departure procedure. Those procedures still entail no turn below 400' above DER (there may be exceptions for unusual [e.g., high altitude] airports, but I am not immediately aware of them). The concept here is that the noise of a low flyby of the beachfront hotels will be a LOT less obnoxious than the noise of 37 million airplane parts scraping along the reefs.

747dieseldude
4th Sep 2007, 21:26
Can't find a reference now, but it cannot be lower then twice the wingspan of the a/c.

sleeper
4th Sep 2007, 21:39
A long time ago, in my 747 Classic time, the engine out sid of well known St Maarten airport requiered a turn at 100 ft to a heading in order to clear the hill behind the runway! Standard company minimum turn altitude was and still is 500 ft. Go figure.

Junkflyer
4th Sep 2007, 21:39
We use pink pages in our Jepps for engine out procedures specific to airport and runway. 8R specifies right turn to 160 degree heading at 1.3 dme off the vor, a little before the end of the runway. Our take off data is now run from a computer program and that also will specify if there is a turn procedure on departure or not. This is for 74 classics.

john_tullamarine
4th Sep 2007, 22:39
Those procedures still entail no turn below 400' above DER ..

Normal AEO turns will be in accordance with the jurisdiction, generally 400/500 ft.

Mandated terrain avoidance AEO turns can be lower, eg Hobart and Cairns in Oz ... unless they have changed since I last flew out of those ports ..

... cannot be lower then twice the wingspan of the a/c.

Unless a specific jurisdiction dictates otherwise, minimum OEI banked turn net flight path clearance is 50ft (which just happens to be very close to the outboard 35 ft delta for an early generation jet in a 15 deg turn). This usually is achieved by putting a make believe 15 ft obstacle at runway head for an early turn or making the sums fit the requirements for a turn beyond the runway. There are plenty of runways where terrain dictates a very early low height turn for the OEI escape.

gimmesumvalium
4th Sep 2007, 23:42
[MY ITALICS] Sorry for the long-winded reply, but here are the quotes from the relevant documents:
SIDs are generally based on ICAO Doc 8168:

2.3 TURNING DEPARTURES
2.3.1 When a departure route requires a turn of more than 15°, it is called a turning departure. Straight flight is assumed until reaching an altitude/height of at least 120 m (394 ft). Procedures normally cater for turns at a point 600 m from the beginning of the runway. However, in some cases turns may not be initiated before the DER (or a specified point), and this information will be noted on the departure chart.

2.3.3 No provision is made in this document for turning departures requiring a turn below 120 m (394 ft) above the elevation of the DER.

However, in the event of an emergency, the following Contingency procedures apply:

1.1.1.2 These procedures assume that all engines are operating.

1.2 OPERATOR’S RESPONSIBILITY
1.2.1 Contingency procedures
Development of contingency procedures, required to cover the case of engine failure or an emergency in flight which occurs after V1, is the responsibility of the operator, in accordance with Annex 6............ Where terrain and obstacles permit, these procedures should follow the normal departure route.

This then refers you to the rules under which you operate (JAR-OPS or FAR-121 etc)
For example, JAR-OPS permits a lower altitude which could be applied for Contingency Procedures.

JAR-OPS 1 Subpart G

JAR–OPS 1.495 Take-off obstacle clearance (Performance Class A)
Track changes shall not be allowed up to the point at which the net take-off flight path has achieved a height equal to one half the wingspan but not less than 50 ft above the elevation of the end of the take-off run available. Thereafter, up to a height of 400 ft it is assumed that the aeroplane is banked by no more than 15°. Above 400 ft height bank angles greater than 15°, but not more than 25° may be scheduled;

JAR–OPS 1.535 Take-off Obstacle Clearance – Multi-Engined (Performance Class B) Aeroplanes

(1) The take-off flight path begins at a height of 50 ft above the surface at the end of the take-off distance required by JAR–OPS 1.530(b) and ends at a height of 1500 ft above the surface;
(2) The aeroplane is not banked before the aeroplane has reached a height of 50 ft above the surface, and that thereafter the angle of bank does not exceed 15°;

JAR–OPS 1.570 Take-off Obstacle Clearance (Performance Class C)
(b) The take-off flight path must begin at a height of 50 ft above the surface at the end of the take-off distance required by JAR–OPS 1.565(b) or (c) as applicable, and end at a height of 1 500 ft above the surface.
(d) When showing compliance with subparagraph (a) above, track changes shall not be allowed up to that point of the take-off flight path where a height of 50 ft above the surface has been achieved. Thereafter, up to a height of 400 ft it is assumed that the aeroplane is banked by no more than 15°. Above 400 ft height bank angles greater than 15°, but not more than 25° may be scheduled.


DEFINITIONS OF JAR-OPS Performance Classifications A, B, C :

JAR–OPS 1.470 Applicability
(a) An operator shall ensure that multi-engine aeroplanes powered by turbopropeller engines with a maximum approved passenger seating configuration of more than 9 or a maximum take-off mass exceeding 5 700 kg, and all multi-engine turbojet powered aeroplanes are operated in accordance with Subpart G (Performance Class A).
(b) An operator shall ensure that propeller driven aeroplanes with a maximum approved passenger seating configuration of 9 or less, and a maximum take-off mass of 5700 kg or less are operated in accordance with Subpart H (Performance Class B).
(c) An operator shall ensure that aeroplanes powered by reciprocating engines with a maximum approved passenger seating configuration of more than 9 or a maximum take-off mass exceeding 5700 kg are operated in accordance with Subpart I (Performance Class C).
(d) Where full compliance with the requirements of the appropriate Subpart cannot be shown due to specific design characteristics (eg supersonic aeroplanes or seaplanes), the operator shall apply approved performance standards that ensure a level of safety equivalent to that of the appropriate Subpart.

NOTE: Significant distinction between ICAO Categories A, B, C, D, E and JAR-OPS Performance Classifications A, B, C - ALSO, FARs may have different requirements for emergencies.

It appears that all references are to the DER(Departure End of Runway) / end of TORA.

So, fit your aircraft type into the above Categories / Classifications for your answer.

GSV

santiago15
5th Sep 2007, 10:39
Slightly tangential question then guys: what angle of bank should you use on a SID? Am I to take from the above that 15 degrees AOB is to be used.

I've looked at the references from PANSOPS and that seems to be what is said.

Intruder
5th Sep 2007, 13:22
Normal for the 747 is 25 degrees; 15 degrees with an engine out.

GlueBall
5th Sep 2007, 14:15
Not making a turn before reaching 400' is all relative. In some airplanes, like a DC6, it could take "forever" to get to 400 feet. With engine out or other associated performance problems [not being able to raise the gear] it may take a lot longer [covering more distance] to get to 400'. You may have to circle the airfield multiple times to climb to avoid high terrain, as at places like Kathmandu. Remember also that the doomed Concorde didn't get higher than 200' with the gear hanging out and No2 engine shut down.

discus2
5th Sep 2007, 14:26
Ok,
I fly very often out of DUB (Dublin). OLONO 1B SID calls "for no turn below 750ft". Then in a squared box it also mentions "No turns before DER".
I am tempted to consider whichever is later.
Now, how do you do that in IMC ? We reach the 750 mark well before the DER on 2 ENG.
Is n t DER the RWY + the clearway ?
Many thanks.

Intruder
5th Sep 2007, 17:20
AFAIK, DER is simply the Departure End of the Runway.

Unless you are in a "high performance" airplane or are taking off on a REALLY long runway, reaching 750' AGL before the departure end would not happen that often. You can gauge it from DME, referencing an appropriate approach plate, if available, or an Inner Marker if installed and operating, or an FMS distance to the next waypoint if it is straight ahead, or timing if all else fails.