Abandoning a S/E Procedure
 

When can pilots legally/safely abandon a S/E procedure? I realize that pilots cannot accept vectors from a controller – at least initially – when performing a Special S/E procedure. The question is – when can a pilot accept a vector (and altitude assignment) from a controller? At Oakland California we have a S/E Procedure which involves a left turn back to the VOR, located at the field, to enter a specified holding pattern. The Obstacle which is being avoided is the Bay Bridge about 5 miles beyond the runway, so it is well behind the A/C by the time you are 180º and basically pointing downwind for the runway. Could you then accept a vector for an approach to the departure runway – you would be flying over the Bay and there are no obstacle involved.

I understand that the controller doesn’t have the performance information to vector an A/C over future obstacles – while still not clear of them – but I assume that, once an A/C has reached the Minimum Vectoring Altitude for an area, the S/E procedure could be abandoned. Is there any rules or guidelines for this?

Thanks for any info,

LK

I don't undestand what you mean for Special S/E procedure.
What type?
BTW, you are in command of your aircraft, especially in an emergency, not ATC, so it's up to you.

Two suggestions

(a) put in a suggestion that your performance people liaise with ATC to develop a more compatible procedure

(b) stick with the published procedure until that point where the procedure indicates that it may be varied

John:

Thanks for the reply. Just to get it straight - these procedures are created by first looking at the performance factors - gradients & obstacles - then they are run by ATC to insure that they don't interfer with traffic conflicts - making sure they don't run through any adjacent traffic patterns, etc. ?

This may sound elementary - but because the Take Off phase of flight only goes to 1500' AGL - would these procedures only pertain until the A/C has reached that altitude.

Thanks for your continuing informative reply's


LK

Loke,

Can't speak for other engineers, generally, but

(a) a particular runway may, or may not, have a variety of sensible departures for the OEI case.

(b) the performance (wo)man's task is to find the one with the best weight (payload).

(c) one would normally expect an appropriate level of flight standards input but this certainly doesn't always occur.

(d) if the terminal airspace is busy it makes sense to gain some acceptance from the ATC people but this very often is ignored.

In any case, for most jurisdictions, ATC will accept an emergency call and do their controlling bit to keep other aircraft out of the way .. but it makes life easier if ATC at least knows what a particular operator's type/escape procedure is .. often forgotten by the procedure designer

(e) although many operators only look at the V1 failure case and leave the pilot to his/her own devices for other cases, a prudent procedure designer will cover failure at any point and climb to a level which gives nett clearance above the highest point .. 1500 ft is the nominal certification case but doesn't have much relevance to the real world if the particular runway environs require the aircraft to be driven to whatever higher level is necessary to clear critical obstacles. Again this doesn't happen with some operators.

The sensible pilot (particularly if you have an effective union representation) will make sure that he/she knows the operator's philosophy and approach to the procedure design activity.

Regretably all too often what I might see as being appropriate is not congruent with what some engineers might do ....

Worth bearing in mind is also that many ATS units (talking Europe here, can't comment on US) are unaware of any particular single-engine procedures, known in my company as "Emergency Turns." Many of these are company-specific as well. Therefore, they may be very surprised to see you turn off the SID, despite a failire. I always include a discussion of what we would say in the very brief call to ATC should we have to fly an Emergency Turn, given the above considerations.

Also, it's worth discriminating between SID tracks which are there for noise only, as well. Certain flat terrain arifields with complex departure turns for noise would find those turns being ignored in the event of a high-weight engine failure, were I in the seat. All with a call of course, albeit brief and to the point.

Squid

I am surprised that pilots would be allowed to disregard a S/E Procedure in Day/VMC. I know of one company which allows a S/E Procedure in Day/VFR conditions only – but there is a specific procedure. I think most pilots would have difficulty estimating there performance S/E when viewing an obstacle in the distance – even if they knew what the restrictive obstacle was – which is usually not indicated in the procedure.

It’s my understanding that in the average twin – you climb is less than 150’ per mile. Many procedures provide an escape route where the critical obstacle may be miles from the field and located opposite the direction of take off. I think I’d stick to the procedure – VFR or not.

John – thank you for you information.

LK

I think I would concur with Loke's comments .. a pilot in the hot seat is not able to make an assessment of gradient (other than by reference to VSI) and, once you turn away from the scheduled escape procedure .. you are ON YOUR OWN ... with a commercial payload and critical conditions .. the distance to climb the net path to a nominal 1500 ft can be a long way .. especially on a twin jet (due to large speed delta associated with flap retraction and low WAT requirements anyway)

j_t / LOKE

Whilst in specific circs you are right, as a generalisation I disagree.

2 cases:
1. EDI 24. Emergy turn is R back to the 24 FAF NDB + hold.... Well, you'll firstly be well popular holding at the FAF for the runway in use. Secondly, if you head ~070, you won't hit anything until Norway. I think I can judge the climb gradient needed to avoid sea...
2. BCN 20. Emergy Turn (while you're heading out over the Med) is immediate right turn to an NDB in some hills. Again, thanks, but no thanks, I'll stick to flying over the (flat) blue stuff.

Emergy Turns are a set of procedures that will keep you safe in all weathers, and from a minimum set of choices. However, in good vis, and depending on the exact circs, following them blindly not only strikes me as unnecessary, but potentially poor A'Ship as well....

NoD

(Both the above procedures are of course type/airline specific)

My previous company had a policy that the S/E procedure had to be followed until 3rd segment height at all times. From that point the procedure depended on the visibility.

In IMC the full procedure had to be followed until safety height or if ATC radar was available, the minimum vector altitude.

In VMC, the Captain had the option of tracking as desired as long as terrain clearance was assured. In practice, a visual circuit and landing would be performed.

Typically, if it was a VMC day, the brief would be something like, "track runway heading to 2 dme then turn left heading 260. Once we've reached acceleration altitude, we'll knock it off and return for a visual approach."

NigelOnDraft:

Actually that was precisely my original point – that there seemed to be S/E Procedures which didn’t seem very realistic – especially at the end - though I’m sure they accomplished the job of avoiding terrain during S/E operations. On the other hand a simple statement that it’s an emergency and the pilot can do what they want, could lead to unintended consequences, especially when more complex S/E Procedures are involved.

I like FlareArmed’s common sense guidance which are procedure at his previous airline. Also john_tullamarine’s always wise counsel to ensure that reasonable S/E procedures are produced to avoid some of the issues that are brought up by NigelOnDraft.

I stick to my statements that it’s difficult for a pilot to evaluate whether a plane will clear an obstacle when they are in S/E operations – even in VFR day. This doesn’t even take into account the obstacle that he is not looking at, which may be miles away – and is really the critical obstacle.

LK

As Nigel has stated, some escape routes are totally absurd and ridicolous.
If I'm taking off toward the sea, like in the LEBL 20 example, I certainly won't head back toward the mountains or incoming traffic.
"Runway heading 3000ft, hold wherever we like over the sea".
End of the briefing.
These escape routes are often defined by wannabees pilots who'd better stay in a university classroom instead of a cockpit.:8

Well this clearly involves some airmanship and opinions may vary somewhat, and this is simply one of many:

On DEP: the emergency turns in rwy analysis are usually for obstacle avoidance and they must be briefed with every departure and followed in IMC. Turns mandated by noise abatement and other 'cosmatic' factors are void and null with emergency declaration. The general practice is to first fly the airplane, do recall items, clean up, reduce thrust to MCT, trim, then call ATC let alone accepting turns. If contacted by ATC in the meantime, decalre emergency and say you'll call back.

Normally they don't give vectors before positive control and 1000' AGL. But if there is emergency turn, you have to include it in your procedure, all the more reason to spend the shortest time on the radio. Once all established, normally ATC helps out by giving vectors for a landing or to your TO alternate as the case may be. If possible, it is probably better to take longer legs on vectors, DME hold, turns on the good engine,... as to opposed to normal tight hold.

On GA however, it is different and one HAS to follow the procedure to avoid obstacles or worse yet collision, unless of course you have time to ask for rwy heading 3000', which is always the best for ENG out TO and GAs.

As for the original question, A ONE ENG INOP procedure ends when the airplane is safely on the ground and PAX/CREW are either evacuated or deplaned!

This is a very interesting & complex subject. In my experience, these emergency turns are usually company specific, and mostly need to be followed at any time there is an engine failure. Day night VMC IMC irrelevant unless specified. The real problem is that ATC are not aware of the particular procedure for each airline and aircraft type.
When the crew is busy aviating and navigating, there might not be too much capacity to inform ATC of needed deviation from clearance. What if the frequency is in use just when you have the chance to make the call? Then what if there is conflicting traffic and you are told to maintain a heading or continue as cleared? Or "are you declaring an emergency?" "how many POB?" "what is your endurance?" "confirm you require to turn left onto heading xxx?" All this just as you're performing near max capacity to get everything else, including communication, done correctly.
I cannot believe we should need to inform ATC of our intentions in the event of an engine failure at every airfield where there is such a procedure. Try this at some foreign airfields and you'll have take-off clearance cancelled or delayed. Probably won't make that slot time. Too many times and you won't have a job.
We cannot ignore the fact that ATC should know in advance of the possibilities. The main point really raised by this post should be how we ensure they do know each single engine procedure for all companies and each of their aircraft types The difficulties don't stop there. If your particular procedure is day night VMC IMC specific, does everyone know which procedure? What if ATC think its night VMC and crew decide its still daylight, but IMC?
A situation I have faced is very out of date emergency turn procedure to a non existant navaid. Even if I do this, its harder to communicate my intention.
At another airfield, very soon after take-off an emergency turn was required over a close spaced parallel runway with exactly simultaneous military traffic on another frequency. The North Asian military controller had a very slippery grip of English, the military thought they were King and the local F/O doesn't want to make waves, no matter how well briefed. How is a controller going to make some traffic space when these guys have actually previously done a barrel roll around my A321 at 500ft just as I became visual on ILS final? If the aircraft is heavy, hot day and tailwind we will hit a hill by not turning. Just hope the military jet will break left to avoid a collision.
My life was greatly simplified by refusing to operate to that particular airfield and then retirement from aviation.
Those of you that have a long way yet to go, and who really care about such matters, have my sympathy. Try to solve this problem somehow.

LEM:
Here Here! By the looks of some of these "procedures" they have no doubt ignored all ATC/Traffic considerations. They use the single (simple?) minded goal to get the company more liftoff weight. End of story.
Fly Safer

Sorry! Back to the original question.
The approved procedure is discontinued when it has been fully completed. If crew decide on safety grounds to discontinue the procedure, that does not seem too unreasonable to me. If the procedure is discontinued for other reasons, the crew may have some difficulty later defending such a decision.
If the procedure specified after a certain point that the remainer was for separation or airspace requirements, I believe following a reasonable ATC instruction would then be acceptable but not otherwise. What is "reasonable"? Depend on circumstances. If you are very familiar with the area and procedures, you are using first language of yourself and controller and radar environment with transponder altitude capability, reasonable is easier to define. Take away some of these more agreeable circumstances and deviation is more difficult to justify. Unfortunately complience is also more difficult.

This is an interesting topic – hate to see it die without generating more inputs.

Do any Operators provide a specific S/E Procedure from a runway to a weight – then if the weight is exceeded, provide a different procedure?

Do any Operators provide a S/E Procedure with optional procedures within that procedure – that is either go to X Intersection and hold, or if above an altitude (or some other criteria) accept vectors?

I think most here have implied that they would not accept vectors from ATC if there was any doubt as to whether it was based on anticipated performance of the A/C, by ATC – that is in the direction of obstacles not yet cleared. On the other hand – many have pointed out the absurdity of going to a holding pattern when you should be heading downwind for a landing – or worse yet driving into a bee’s nest of traffic when a safer course is evident.

The issue of whether ATC does know – or should know about these procedures - is another interesting question.

LK

Interesting topic.

the day VMC question is always a hot topic, and in my opinion visually avoiding terrain simply means that you see the hill as you run into it!

35 (or 50) ft isn't much, adding gross to net margins doesn't add much really, and in most cases if you depart RTOW (obstacle) limited and have a failure you will get GPWS etc blaring in your ear.

Saying that you can determine visually that you can miss that hill over there is unrealistic in many cases, and simply gives the pilots a false sense of security.

Another interesting topic is airmanship.

many are quick to accuse others of lacking airmanship, but to date I have yet to see the definitive manual on airmanship.

What is one persons definition is different to another.

Food for thought!

Loke
Do any Operators provide a specific S/E Procedure from a runway to a weight – then if the weight is exceeded, provide a different procedure?
At airports which require extra zoom, we have different takeoff charts for normal t/o at light weights and asterik charts whciha require a special S/E procedure - difference of maybe 3 tonnes paylaod, and different clean up heights.

Couple of points.

(a) the net to gross margin doesn't give you much fat to play with near the departure end of the runway (depends on which case is limiting and how limiting the runway is) but provides a significant margin by the time you get to the fourth segment particularly.

(b) no reason why you can't have several procedures for one runway based on whatever criteria a particular operator considers important or appropriate .. only depends on how much work the operator wants to pay for.

The original post that started the thread by LOKE talked to a S/E procedure for Oakland CA that turned the A/C back to the airport navaid to avoid the Bay Bridge. I'm thinking that a part of that procedure may be designed to avoid traffic from SFO, NAS Alameda, San Jose, NAS Moffit Field and goodness knows where else as well as terrain and very changable local wx.

A particular consideration in this case should be the communication with ATC. Presume this qualifies as an emergency, so the short radio call and executing the procedure that gets you out of the immediate danger and keeps fairly clear of other traffic seems to be the best course.

This subject gets the attention it deserves by just a few. Airlines and aviation authorities are not amongst them.

Both are only interested in cover my a*s policy.

Which airlines make the effort to ensure air traffic controllers are aware of their particular S/E procedures?

The sensible ones which pay more than lip service to risk assessment and mitigation.

For procedures which generally accord with normal traffic patterns, SIDs, etc., there is probably no need to worry too much about ATC advice .. although .. those good folk might presume a much greater climb gradient AEO and factor that into traffic conflict planning .. and then along comes Bloggs OEI at, say, 3 percent or so ....

If there is likely to be a surprise factor for ATC, then it is pretty silly not to have them on the distribution list for the procedure. This might not cover all bases but goes some of the way.

For odd-ball procedures where the potential surprise factor is high, then I opt for the "give ATC a briefing on the procedure" in association with distribution. I have to say that I have never had any responses other than interested and appreciative from ATC offices for such an approach.

There is a resources (labour and cost) overhead involved, of course...

J_T, we have tried having that discussion with various ATC units, none of them wanted a procedure that wasn’t approved by their own authorities. We have spent over one year trying the get the Iranians to change the MAP gradient for a specific airport, they have redesigned it, flight tested it and for the last 6 months have waited for the signatures . Our OEI procedure for that airport doesn’t comply with their ICAO standards, there is no way that they are going to accept the procedure and there is no way that we can accept the SID departure. :)

Mutt.

One of my primary tasks in performance engineering is the design of Specific Runway Procedures for OEI operations, call them escape routes if you will, they go by many names. A vitally important follow-up of this procedure design is the advice to pilots, through operational policy stated in the Operations Manuals, of how they are to be executed, and when circumstances may permit 'breaking off' as posed in the original post. And YES, for each one I have designed and implemented, I have personally visited the relevant ATC unit to advise of our requirements in the event of engine failure. They have been very receptive to this, I have not had to deal with the Iranians Mutt.

Before any discussion on appropriate circumstances to break off from an OEI procedure, it is appropriate to briefly detail the considerations that I make in creating a procedure.

(1) The procedure must be such that the maximum possible weight for takeoff may be obtained after considering all obstacles UNTIL SUCH TIME as the aircraft reaches an area where normal (PANS-OPS) obstacle clearance exists. This is usually the MSA.

(2) Even though 3rd segment altitude will almost always be below MSA, obstacle clearance must be assured AT the 3rd segment altitude for the remainder of the procedure, thus avoiding obstacle assessment during the 4th segment. This will require tracking procedures, normally directed to a holding pattern, where further climb to MSA may take place. (The holding pattern may not be a published one, but one created to meet FAR25 requirements for the continued climb). The published procedure MUST continue until MSA is achieved, the pilot does not have the facility to assess obstacles.

(3) The entire procedure will be contained within the MSA coverage, normally 25 nm, and within the control zone of the departure airport.

(4) All procedures must avoid areas of known high traffic density, such as secondary airports, VFR operations areas, and the approach and departure paths from the originating airport.

(5) Where a SID requires a turn BEFORE a turning point specified in the OEI Specific Procedure, a second RTOW is created for OEI compliance with the SID. If the Actual TOW exceeds this 'SID compliant' weight, ATC must be advised and the alternative procedure used.

These are the basics of the criteria that I use, in my opinion any performance engineer providing a lesser degree of protection IS SIMPLY NOT DOING THEIR JOB.

All engine failures do not occur at night and/or in IMC, and in the Operations Manual write-up, the following is specified as acceptable circumstances for the pilot to 'break-off' from a Specific Runway Procedure -

(1) The procedure may not be terminated under any circumstances before Acceleration Altitude is reached, the aircraft is in the en-route configuration, and thrust reduced to Maximum Continuous, and either

(2) In VMC conditions by DAY, normal obstacle clearance to comply with the VFR rules is assured, or

(3) At night or in IMC, the aircraft has achieved sufficient altitude and within the required tracking tolerances to comply with a published Holding or Instrument Approach procedure, or

(4) At night or in IMC, the aircraft is at such an altitude to comply with the ATC Radar Safe Altitude and is receiving Radar vectors.

A bit lengthy, I'm sorry, but I sleep easier at night knowing that the crews using my procedures have full obstacle assurance all of the way to where they can resume normal operations with PANS-OPS protection, and have a clearly defined flight path offering the best foreseeable traffic avoidance.

A final word to pilots using visual obstacle assessment, it's not usually the obvious big obstacles that are 'gonna getcha', it's the little subtle ones.

Old Smokey

One of the funniest escape routes I've seen was for RWY35L in LIMC: instead of turning left as per Sid, it called for a RIGHT turn crossing the missed approach of 35R!

In the name of a higher payload. :yuk:

Emergency Turns are so called because that's what you are going to do in event of an engine failure (which I would call an emergency!) in order to ensure compliance with performance requirements.

They are usually promulgated by the company when the straight climb out would make the RTOW too limiting.

In all the companies (UK) that I have flown for all our emergency turn procedures at specific airports were pre notified to ATC by the Nav Dept. Whether a specific controller on the day is aware of the company emergency turn is another matter!

I would like to pick up on the points made by Nigel and LEM stating that they sit down and plan in advance to ignore the OEI procedure and simply fly the aircraft out to sea because they considder flying to a point over land to be a silly idea in the circumstances.

Could it be that the person who approved the procedure in the ops manual (Chief Pilot?) believes that when a twin has an engine failure and becomes a single engine aircraft, taking a public transport flight in a (now) single engine aircraft well out to sea would not be ideal if the aircraft could acheive obstacle clearance over land?

Just a thought.

Regards,

DFC

PS - What's the rush to ditch the procedure? Isn't the idea that in an emergency we don't rush things unnecessarily?

LEM, circumstances like you describe are not too uncommon. It is unlikely that all operators to such an airport would brief ATC on their s/e procedure. One day there will be a mid-air & the !!!! will hit the fan world-wide, as airlines & ATC try to profess their ignorance of the risk and blame it on the crews. Its not so serious at a purely domestic airport with just a couple of good airline operators. Make it international with lots of airlines, throw in a few african freighters, fatigue, weather, english as a 3rd language, cultural difficulties etc and the risk is higher. There are a lot of controllers, pilots and aviation authorities with their heads in the sand.

I'd like to add my "tuppence worth" to the post by DFC. Heading out over water, while it is a very tempting idea, would require the pilot to assess the risk associated with the existence of a super tanker, aircraft carrier, or any similarly tall vessel, crossing the extended centreline of the runway at the critical moment.

How high will the aircraft be at that point?
How tall is the ship?
Where, exactly, is the first point where the risk exists?

And then, of course, is there any possibility of the existence of an amphibious aircraft operation at the critical time?

Of course, as DFC suggests, even without such a problem, how high is the aircraft going to be in the first couple of miles? How much time will there be to go thru a ditching drill and get the pax ready for that?

These might be some of the reasons why an emergency procedure avoids going over water for anything but the shortest possible time.

As for the reference made by autoflight that "There are a lot of controllers, pilots and aviation authorities with their heads in the sand." I think it needs to be said that there is no clear way for ATC or regulators to predict the climb performance of any particular aeroplane in any given emergency situation. If pilots actually want these emergency procedures to be standardised, it will undoubtedly have to be taken up with ICAO (for Pans Ops) and the FAA (for TERPS).

And, even if you can get those two to actually agree on a standard forumula, it is likely to cater for the worst case scenario only. And that will undoubtedly result in a heavily reduced payload for most aircraft. This whole argument can go around and round and I can't say that I have any suggestions on ways to improve the situation - I'm sure that I'd be a millionaire if I could do that.

Plan A: There will be many runways where the escape route is obvious and can be selected as standard. Operators wishing to substantially comply with the standards set for each such runway will not be unduly penalised by following them if required. The airways clearance would automatically include a contingency for the standard s/e procedure. Operators will normally go for the standard, rather than have their flights delayed by a special contingency clearance .
PLAN B: If an operator wants to squeeze in the last kilogram of payload / fuel on a regular basis, and devises a s/e procedure that is better able to do this, it could be annotated on the flight plan. If this case, the departure clearance will include a provision for that.
For runways where the escape route is not so obvious and operators choose different s/e routes, see Plan B.

Good discussion.

Something that occasionally passes through my mind is the S/E G/A. You have taken off, had your engine failure, followed the ET, climbed to MSA, etc. then returned to the airfield, unfortunately becoming unable to land at the last minute (maybe using a different runway to the one you took off on).

I understand (and I stand to be corrected) that most performance calculations only give obstacle clearance out to 1,500' AAL, clean and after that you are on your own. Given that SID profiles are normally quite different to missed aproaches, should consideration be given to flying a departure instead of a G/A?

If you end up landing (or attempting to land) on another runway, you may be unable to make the gradient required on the appropriate SID but also be 'in the poo' if following the standard G/A...

Maybe the answer is something close to a missed 'circling' approach, involving manoevring to get on an appropriate departure, although terrain at some airfields may negate this.

Anyone got any particular thoughts? :confused:

I always briefed for terrain clearance following GA. If required, minimum clean speed & T/O power to the time limit. I agree that not enough consideration is given to the gap between 1500ft and safe altitude. If the authorities and the airlines don't do it, it is up to each captain to do so.

It is a good discussion.

I find it very disturbing to read here and there of pilots who want to 'reinvent' the OEI procedures, break off and head out to sea, or attempt to follow the SID. How well did the proponents of such ideas survey the new field of obstacles in doing so ?

Obstacles are assessed very accurately for OEI Special Procedures, and the optimum path chosen. They have to be, margins of obstacle clearance to comply with FAR25 (or it's equivalent) are EXTREMELY small, and small obstacles that wouldn't cause a moment of consideration for crews familiar with a particular airport during normal operations can become critical.

Consider a 100 foot radio mast at 1 nautical mile from the departure end of a 3000 M runway. At the line-up point, can you accurately assess this mast at a distance of 4.8 Km, a mere 1/3 of a degree above the horizontal to the pilot's eye position ? Well, it's a critical obstacle for a 2 engined aircraft at performance limiting weights. So too is a 6 foot man at 1000 feet from the runway end. Now put these same 'indiscernable' obstacles in the 'reinvented' OEI route for those who want to take another route and see the outcome. As I said in an earlier post -"it's not usually the obvious big obstacles that are 'gonna getcha', it's the little subtle ones".

I see cynical remarks in these posts regarding procedures to squeeze the last possible Kilo of payload. Do these same cynics realise that if the performance engineer has chosen a route that obtains those last few kilos of payload, that this must imply that that is the path with the LEAST obstacles, and is therefore the SAFEST. This is one of those rare cases where if you choose the SAFEST option in terms of terrain clearance, then it is also the most commercially viable. A rare marriage.

DFC, you made the statement -"Could it be that the person who approved the procedure in the ops manual (Chief Pilot?)...etc", The procedures are created by performance engineers poring over incredibly large scale survey charts, municipal maps, etc...stuff that is not available amongst normal aeronautical charts etc. These fall far far short of adequacy to evaluate safe routes for OEI procedures. It is a full time job for P/Es and their staff.

It is acknowledged that there are some lousy procedures "out there", but properly designed procedures get you all the way up to MSA, and DO consider high density traffic areas etc., including the shipping alluded to by OzExpat. Do the OEI reinventers consult the shipping authorities to ascertain the largest vessels able to use over-water areas envisaged ? I do. Again, the 'lousy' procedures stick you with one single procedure, often incompatible with the SID. A good service provider will supply OEI data to comply with the SID (usually much more restrictive), in addition to the optimum data over an optimised route, which, if required for your actual Takeoff Weight, must be advised to ATC.

OEI procedures are created by, and provided by the operator (or the operator's sub-contractor). There is a good case to canvass, at ICAO level, for standard, optimised, OEI escape routes for all runways. Until that time, it is an issue that pilots must take up with their management, or their performance engineering departments.

Until that time, for God's sake, for your sake, for your passenger's sake, follow the OEI published procedure.

Please.....I might be one of your passengers.

Old Smokey

Old Smokey, absolutely - well said!

I never cease to be amazed at the number of crew who believe that they are protected for obstacles when they fly a SID with an engine out. :)

Not always true, we have particular airports where we know the required takeoff weight, its not achievable on any of the SID tracks. Therefore the OEI is unique.

I would love to say that this is always true:(

I would love to see ICAO level, for standard, optimised, OEI escape routes for all runways. It would make life so much easier and safer.

Mutt.

Mutt,

My quote - "A good service provider will supply OEI data to comply with the SID (usually much more restrictive)"

Your quote - "Not always true, we have particular airports where we know the required takeoff weight, its not achievable on any of the SID tracks."

To qualify this, SECONDARY data is made available for those SIDs which can accomodate 'reasonable' weights. Certainly not all of them. PRIMARY data is always available via the OEI route, invariably different to the SID.

Regards,

Smokey

Re obstacles and obstacle profiles .. it depends ...

(a) if an obstacle clear gradient is declared by inclino survey, then that's fine ... you just lose some payload (usually) but it is quick and dirty to calculate and fly the straight flight path.

(b) pity that some in (a) are done by working back from the topo or Type A .. defeats any cost and utility value of inclino surveys.

(c) Type A is fine .. but, for a jet twin, especially with a big V2 to fourth segment climb speed split ... usually doesn't go anywhere near far enough .. does 40-50 nm takeoff path cause any concern in some cases ... ?

(d) generally, the ops engineers are on their own .. on quite a few occasions, either we throw a theodolite over the shoulder to go and do some rough field work, and/or commission a surveyor to do the work for critical obstacles if they are sufficiently critical ...

(e) lots of useful data around but, at the end of the day .. muddy boots and a 4WD sort out a lot of critical problems ..

Fortunately, for most departures, the topo etc., data can be used to identify critical bits outside/beyond the Type A or equivalent. One needs to keep in mind that, in the event of an early turn taking the aircraft out of the Type A splay ... the ops engineer is back to basics.

And, at the expense of repeating what my colleagues keep saying .. the guy in the sharp end can't estimate the delta between climb needed and climb available .... a bit late in the last 20-30 seconds to realise that that is the case ...