Engine Failure on Takeoff! Flight Path? [Archive]

beamer

17th Jul 2001, 20:25

1. Fly the aircraft.

2. Follow the Emergency Turn if one exists
in your performance manuals.

3. If no ET - I will climb straight ahead
and ignore noise considerations as I have
by definition lost either 25/33/50 per cent
of available thrust dependent upon ac type.

4. As the primary objective at this stage
is to fly the aircraft, gain altitude, initiate drills, ATC calls, complete checklists etc, I do not want to carry out
a complicated SID which may jeopardise the
previous actions. An ET is an exception but
in that event drills would not normally be
completed until completion of the turn.
It could be argued of course that a simple
SID would present no problems but where does
the line lie between a simple one and a
complicated one ? It is of course imperative
that pilots should be aware of terrain and
possible areas of conflicting traffic AND that ATC are informed as soon as possible of
intentions ie ' MAYDAY CALLSIGN XYZ - ENGINE
FAILURE - CLIMBING STRAIGHT AHEAD - STANDBY'

5. This is a difficult area as different
operators will have different SOP's and ATC
units around the world will no doubt have
their own regulations and indeed expectations.

6. At the end of the day it is the final
responsibility of the crew to maintain the
safety of the aircraft in whatever dire state
it may have fallen into and the measures
needed to achieve that end result will vary
from flight to flight. Therefore we should
not fall into the trap of treating every
departure(to quote your example) the same
because being technically correct will not
always stop you flying into the hill. Each
take-off is different and what may be a
suitable course of action now may not be the
best course of action tomorrow - think it,
brief it, fly it and keep safe !

mutt

17th Jul 2001, 21:06

There seems to be an opinion that SIDS are based on a specific number of engines. I would suggest that they aren’t! They are based on TERPS / ICAO ANNEX 16 (I believe) and involve a specific gradient.

This gradient is designed to get the aircraft clear of obstacles, noise, ATC crossing gradients etc etc. The reasons behind the specific gradient isn’t available to you as a crewmember, all that you know if your aircrafts climbing ability with all engines and one engine out.

Therefore your only safety is your knowledge of your aircrafts abilities!

Now for a couple of questions:

As for the idea of flying straight ahead, just how far are you planning to go?

With FMC equipped aircraft, would it not be easier to fly a programmed SID rather than flying straight ahead?

Thanks.

Mutt.

Slick

17th Jul 2001, 22:34

Mutt, quite correct, nothing to do with all eng's operating, however in many cases all engines are assumed, SID's are not as you say constructed for the a/c with one or two eng's out. They are obsticle or noise routes the former tends to list a min climb gradient to a certain height as you know. Now for the scary bit, who knows what there a/c will achieve/climb gradient, and I am not of course talking about the minimum gradient requirements, I am thinking about an eng failure half way through a sid, eg leaving 1700 for 8000.

Best Rgds

TE RANGI

17th Jul 2001, 22:54

Our company SOPs mandate a straight out departure or follow an emergency turn procedure (we call this SEOP)if that is published, but not the SID.
Take-off performance (i.e. the Max allowable TOW you can depart with at a given rwy and conditions) is based on a predetermined obstacle clearance according to FARs/JARs. Obviously all airlines want to uplift the max possible weight to take advantage of max payload/range missions, so all Emer Turn procedures are based on the track that requires the minimum climb gradient.
ATC units are supposedly notified of your company's emer procedure, but I wouldn't bank on this. Thus, if you face an engine fail there's yet one more thing to add to the workload: A prompt declaration of emergency.

NorthernSky

17th Jul 2001, 23:11

First, my view:

If there's an ET, follow it. It's there for a very good reason, though the reason may not be immediately apparent.

If there's no ET, then go straight ahead. The NTOFP is analysed for terrain this way, the SID isn't. In fact, data is not available to analyse the SID track accurately in much of the world.

There is, however (and this is where it gets boring) a query over interpretation of ICAO document 8168 on this topic. It states that one should follow the 'departure route' following a malfunction on take-off. Some interpret this to mean the Standard Instrument Departure (capitalised and with that word 'Instrument'). However, there is no written clarification available, to my knowledge.

My own view is that in the immediate moments after a malfunction, climbing straight ahead is by far the safest option, and should only be deviated from where there is a safety reason not to do it. That said, a 'proper' automatic aircraft (Airbus or Fokker, for example) makes such a good job of flying the EOSID that the case is less easy to prove.

It is difficult to make a safety case for poling a Boeing around a fifty degree turn by hand at 500ft AAL immediately following a malfunction, simply because 'someone' says you should follow the SID.

Last Sector Power

17th Jul 2001, 23:47

I hope I'm not down the back when all you people fly straight ahead on one engine, below MSA & in IMC not following any published procedure. Lets hope there isnt a bit mountain in the way where the SID would turn you away.
The reason for most Emerg turns as the A/C can't make the required climb grades on the SID with a failure (standard SID 3.3%, noise requires may be a lot higher but are not a requirement in the event of an emerg, As Mr Jepperson states in the front of those big books in the cockpit) so if you dont have a ET and can't make the SID then what the F*** are you doing taking off knowing in the event of a failure you can't out climb the terrain :mad: :mad:
The other option is to have a higher takeoff wx limit ie- not going IMC before a set height, so if this is not made you can circle to land(VMC), if it then fails you have already out climbed the SID to a point and form there (with a/c actual %) you will still clear obstacles.
Missed approach is 2.5% so it follows if the above are met you are ok (a lot of companies i know have a higher MDA/DA with an engine failure so obstacle clearence can be met in the event of a MAP if you you cant make 2.5%)

If you can't make any of these and you still depart you have either have BIGGER Nuts than me or less Brains (take your pick but its not first I would quess) :D :D :D

tired

18th Jul 2001, 01:13

Err, L.S. Power, I think you've got the dog by the tail there, matey, if you're talking about scheduled airline ops, anyway.

Perf A aicraft have to meet certain climb criteria with an engine out before they're certified. (No, I can't remember what they are, though 2.5% for 3 and 4 engined aeroplanes rings a bell). Provided you adhere to the performance criteria (WAT limits etc) you will clear all obstacles within an expanding cone based on the departure end of the runway if you continue straight ahead, unless there is a close-in terrain constraint that intrudes into that defined area,in which case the airline ops. dept. must establish an emergency turn procedure.

SIDs will obviously keep you away from the terrain, but that's not their primary function - can you think of any terrain constraints to the west of LHR that necessitates an early turn left or right? Those LHR SIDs are there to keep you away from other traffic (and the local MP's house :) ). Of course some SIDs do have terrain constraints to consider and these often show up as minimum climb gradients to certain altitudes, or a requirement to remain visual to a certain height or somesuch.

Hope that helps.

tired

18th Jul 2001, 01:17

Ah, and after the previous long post, I forgot to answer the orignal question - isn't old age wonderful! ;)

Our SOPs are 1)follow any emergency turn 2) continue straight ahead if you have not yet begun the first SID-induced turn 3) if you have started a turn then continue on the SID -because otherwise you won't know where you are and L.S. Power's concerns will become valid. :)

askop

18th Jul 2001, 10:04

Interesting topic.

I thought JAR/FAR 25 acft had to calculate the eng failure climb gradient before each takeoff. So why not follow a SID if the acft meets the procedure. Where I come from we have a lot of SID's with gradients well above 3.3%, but what is the typical gradient for a acft with one engine out (i.e B737,A320 etc)?

For the record. I don't fly transport cat. acft yet!

m&v

18th Jul 2001, 11:07

Depends on your Runway analisis criteria.Part 121 inthe states follows the FAA swath which is nearly as critical as the ICAO swath(much wider to cover crosswind effect-an further out).Ergo if one can follow a climb gradient of 200'/nm one can comply with the SID gradient.With an engine out,if the Obstacle clearance swath is formated on ICAO criteria one must take up a specific heading to clear the rocks.A lot of Co's have not adopted the Icao,ergo one might follow the Sid Routing with out the nescessary obstacle clearance.. :eek: null

beamer

18th Jul 2001, 11:59

L S Power - you are missing the point !
I am not suggesting that following an engine
failure at or above V1 I would climb straight
ahead ad infinitum. I did say in my earlier
reply that every departure is different and
that pilots should always be aware of terrain
or other implications in the immediate area
of the airfield concerned. Climbing straight
ahead, leaving aside emergency turn implications, enables the crew to carry out
drills without the added concerns of navigation for the first couple of minutes.
Once the aircraft has reached say 3000ft agl
and the situation has stabilised the aircraft
can be directed, hopefully in co-ordination
with ATC, according to the requirements of
the situation. Obviously, if the failure
came at a later stage in the departure when
the autopilot was engaged more options are
available to the crew - if the SID has already been commenced (ie a turn) then it
would make sense to continue that manouevre.
Most respondents like myself are working on
the worst case scenario of a failure at or
just above V1 when the aircraft is still on
the ground.

There is no easy answer on this one, a dozen
pilots will come up with a dozen different
ideas BUT the important issue is the one I
will always subscribe to - know your aircraft
and consider the options for each and every
departure and brief them prior to launch.

Flier Tuck

18th Jul 2001, 13:25

Good points all around.
Does your company/operator analyse obstacles of all runways/airports that you operate into? ;)
What about a 'Single' Engine Missed approach (an airport in a mountainous region - follow the Standard MAP?) :confused:
What does ATC think? (This is really interesting as well) :)
Looking at the varied opinions on this post, imagine how many of operators out there know what to do in IMC, at an airfield with obstacles, 'foreign' ATC, etc!
Thanks for the posts.

mutt

18th Jul 2001, 14:07

For those of you who think that flying a SID is safer than flying straight ahead, I hope that you enjoy the following article.

The weather in Las Vegas is 500 feet overcast and 2 miles visibility with rain showers. You are departing via the OVETO NINE SID in an L1011 climb weight limited aircraft. The takeoff briefing is completed with the following statement: “In the event of an engine failure, we will climb to 3175 feet and request radar vectors back to an ILS approach for runway 25R” Ten minutes later you are following down RWY 25R towards V1 and the appropriate call-outs are made, “V1, Rotate.” Just after rotation the number 1 engine fails. You continue climbing towards 3175 feet. Passing through 500 AGL, you advise ATC of the emergency and ask for radar vectors back to land. To your surprise ATC says that they cant supply vectors until you have reached 4000 feet, which is the minimum vectoring altitude (MVA). After some unsuccessful discussion with the controller, you elect to fly the published SID until reaching MVA, since you are certain that it guarantees terrain clearance.

About the time you finish your discussions with ATC, you are passing the 4 DME turn point on the SID and start your turn to a 070° heading. As you roll into the turn you notice that your climb rate is decreasing, you also notice that the radio altimeter is decreasing even though you are still climbing. Halfway through the turn you notice that the radio altimeter is now reading less than 50 feet and continuing to decrease. In seconds you no longer have time to figure out what went wrong.

What went wrong was the SID, and all other procedures based on the United States Standard for Terminal Instrument Procedures (TERPS), only guarantees obstruction clearance when your aircraft can meet the minimum climb rate for the procedure. Lets take a look at what TERPS requires.

TERPS Climb Requirements.

“Based on the aircraft climbing at 200 feet per nautical mile crossing the end of the runway at 35 feet AGL, and climbing to 400 feet above the airport elevation before turning unless specified in the procedure”

TERPS Obstruction Clearance Plane.

“A slope of 152 feet per nautical mile, starting at no higher than 35 feet above the end of the runway is assessed for obstacles. If obstacles penetrate the slope, a climb gradient greater than 200 feet per nautical mile many be added.

From these definitions we can see that TERPS normally requires a minimum climb gradient of 200 feet per nautical mile and that the difference between the climb requirement and the obstruction clearance plane is the operating margin of safety. In the case of OVETO NINE from LAS, the procedure specifies a minimum of 280 feet per nautical mile (700 fpm) to 6000 feet. After your engine failed departing LAS, your aircraft was climbing at 2.7% (3 engine AFM limit) which equates to 163 feet per nautical mile. After entering your turn, your climb gradient was further reduced due to a portion of the lift being vectored into the direction of the turn in order to maintain the aircraft’s bank angle. As you can see your aircraft was climbing at a rate well below the required 280 feet per nautical mile, but worse yet, your aircraft was below the TERPS obstruction plane where obstacles are known to exist. This means that in order for you to be guaranteed adequate obstruction clearance when using an IFR procedure, your aircraft must meet the minimum climb requirements for the procedure, regardless of the number of engines operating. (Note, this article is at least 7 years old, so the OVETO NINE may not exist anymore or may have changed.)

Beamer, do you know how long/far its going to take you to get to 3000 feet? I suggest that you look at the topic about “Takeoff to 1500 feet.”

Flying straight ahead usually gives you a protected track of around 12 miles (AIP type A chart data), in this time, you are expected to decided upon PLAN B.

Mutt. :)

mutt

18th Jul 2001, 21:08

This part of the same article deals with the Missed Approach!

FAR 121.195 which specifies maximum landing weight requirements, refers to FAR25 aircraft for approach climb gradient requirements. For a 3 engine aircraft the required engine failure climb gradient at maximum landing weight is 2.4%. This gradient is the equivalent to 145 feet per nautical mile which is well below the minimum TERPS required climb gradient of 200 feet per nautical mile and the TERPS obstruction clearance plane of 152 feet per nautical mile. When you include the acceleration/clean up segment of an engine failure missed approach, the resulting actual climb gradient is even lower. From this information you can see that you are not guaranteed obstruction clearance on a TERPS procedure during and engine failure missed approach!

Mutt http://www.stopstart.fsnet.co.uk/smilie/guin.gif

john_tullamarine

18th Jul 2001, 21:41

Having great trouble logging this post ... hopefully it appears only once ..

Seldom do I have the chills up my spine which I have from reading this thread.

Most airlines schedule for a V1 failure only .. with an escape path if necessary. They ignore the case of a failure post V1 on the climb to enroute conditions. This I know applies in a number of quite large international airlines. I have just started a contract with such an operator and sat in on a pilot performance lecture this morning. When I asked the PE lecturer this question his answer was to the effect that it was the pilot's problem.

A sensible flight department will ensure that its ops eng support team provides analyses of failure at ANY POINT in the post takeoff flight path until enroute clearance has been attained... certainly that is what my operator clients get.

What it boils down to is this ...if YOUR people only look at the V1 failure case and you have a failure airborne .. then you are on your Pat Malone my dear .. if there are any hills of note around then you are, very likely, DEAD MEAT !!

Forget SIDs ... they have nothing to do with OEI escape paths and generally the relevant preambles make this quite quite clear.

Please do ask your ops engineers what they do and do not include before you go off assuming things which, perhaps, you ought not to .....

Chimbu chuckles

18th Jul 2001, 22:53

Ahh, wonderful stuff this !!.

I think we are pretty much on our own a lot of the time. I used to fly for an airline that operated jets in very high DAs and we had Jepp Special Procedures that dumped us at 1500' AGL which was about 10000' below MORA, with terrain VERY HIGH and VERY CLOSE that went for F**KING MILES in every direction! We knew the area like the back of our proverbials and so had some more 'home grown stuff' that would give us maximum chance of surviving said V1 bad news.

Now I'm CP for a Bizjet op where we operate into places on 'one offs' or rarely. We go to Kunming for instance(6300amsl/MSA 11800ish) at 2am (twice lately) and I had to sit down with one of my Captains and work out WTF we would do in case of trouble.

We worked out that by following parts of several SIDs that dovtailed nicely we could make MSA on one engine and ended up at an NDB from where we could join an arc for an ILS back to land. Any one SID required a minimum of 5% climb gradient.

My/our SOP for Kunming requires that we fly our 'escape route' no matter what to MSA(night/IMC) just in case one fails below MSA but after V1.

Straight ahead is good often times but I only go to 10 nm and then turn back to overhead.

As a general rule I use CAT C or D circling minimas(Pan Ops version ie 4.2nm for C or 5.28nm for D. TERPS 1.7nm for C how do you guys do it??) as accel alt and if an IMC departure was the go and I was not familiar with the surrounds would usually look carefully at the Missed Approach Procedure for the runway I'm using and maybe follow that.

If terrains not an issue but traffic is following a SID is good, particularly in less 'developed' parts of the globe.

Don't give a rats about noise and if I can roar over an MPs house and ruin his day well that's a bonus :D

Bottom line? A dogmatic approach will kill you! Every departure is different and requires thought. Even different times of the day off the same runway in severe clear VMC could require a different plan of action for one reason or another.

Just bloody glad the weather is not THAT BAD THAT OFTEN so can 'manouvre visually clear of terrain' totherwise I might get stressed :D

Chuckles.

[ 18 July 2001: Message edited by: Chimbu chuckles ]

beamer

19th Jul 2001, 00:20

Mutt

Thankyou for the Vegas scenario - I used to
do some flying at the quiet little military
place just down the road - I well remember
the size of some of f*****g hills !

When I quoted 3000agl I did so as a figure
on the top of my head - time taken to reach
that altitude will of course depend upon all
the usual factors associated with aircraft
performance - I'm glad to say that my jet
is not short of poke even single engined at
high groos weight. The essential fact stands
that options ON THE DAY have to be thought
out prior to departure.

safety_worker

19th Jul 2001, 12:23

Hi,
First of all, the posting by 'flier tuck' was by me. :confused: I can't seem to understand how it got under his name. replied to my email from pprune in this hotel here and clicked to reply and posted. It did under his name, which I realised after it went back to the forum. In a rush to catch the transport and missed apologising earlier. :o
Back to the forum -
Mutt - 'All ' SIDs don't guarantee an engine failure obstacle clearance. I believe it's the operators responsibility to verify obstacle clearances for its type of aircraft at the fields it operates out of, and then if necessary create an EOSID/Emergency Turn 'guaranteeing' obstacle clearance!
How far do you go straight ahead? - 10 minutes! I 'think' this distance (varying speeds) can be determined by the operator using Max Structural TOW. All obstacles in this 'cone' will have to be considered, otherwise an ET (emergency turn) produced.
I quite agree with the MAP. You 'may' not be guaranteed obstacle clearance as in the SID. An ET, single engine missed approach point will have to be created (height/altitude).
John, I agree with you, however, to consider various points in a SID at which a pilot can have an engine failure and then work out the obstacle clearances from those various points is a very, very hard task.
The norms for creating an ET will have to be determined first, before studying the obstacles around the airfield (range? To be determined!)
I don't think all situations can be covered. The pilot has to know his airfield as well. One can always ask their 'performance man' questions. Talk to the boss and create a rule for ET.
Beamer - absolutely right! The options for the 'day' have to be thought out and briefed on the apron.
Still no ATC input? Their story is also quite interesting! :(

BOAC

19th Jul 2001, 15:00

Just be VERY careful as to when you do not follow the SID. Some companies predicate emergency turns ONLY when the EO SID flight path is unsafe and you MUST be very sure before continuing straight ahead (or, equally, accepting an ATC 'early left-turn direct XYZ approved', etc BEFORE the donk goes), that you have satisfied the ANO and you have ensured a safe flight path in the event. As JT and others say, know the basis of your company's calculations.

My understanding is that ATC will expect you always to follow the SID unless you tell them.
Pilot (Old)

[ 19 July 2001: Message edited by: BOAC ]

safety_worker

20th Jul 2001, 12:31

Isn't an EOSID an 'emergency turn' of sorts?
Remember we are considering twins on this thread. I don't fly airbus. I thought an EOSID may be -
a. the SID itself with different gradients as opposed to the SID itself.
b. straight ahead(?) ;)
c. emergency turn back ending back at the airport VOR/NDB/IAF
d. ?????

Where are the ATC (opinions) when you need them? :D

BOAC

20th Jul 2001, 13:41

Apologies for any confusion here. By 'EO SID flight path' I mean the flight path following the NORMAL SID, engine out. I am not aware of such a thing as an 'EOSID'- surely it could not be 'standard' by definition?

[ 20 July 2001: Message edited by: BOAC ]

tired

20th Jul 2001, 15:41

Safety Worker. you're correct. An EOSID is designed to keep you out of the hills with one donkey on strike. It has been designed taking into account the known performance of the aeroplane in the engine out config.

BOAC - it's Airbus terminology, don't suppose they had those in your day ;)

Max Angle

20th Jul 2001, 17:18

Very interesting thread, there is a bit of a debate going on in our company at the moment about this very question. The two sides of the debate are: 1) If there is no engine out SID, obstacle turn etc. then follow the normal SID and 2). Go straight ahead UNLESS there is an EO SID or obstacle turn. Assuming the worst case of failure at V1 then
in my opinion the second option, straight ahead, is the ONLY safe option for the following reasons.

Firstly consider how Perf A. (or whatever it's called under JAA) calculates obstacle clearance. At the end of the TODA an area begins that is 100m + a wing span wide. This expands at a rate of 12.5% of distance out to a maximum of 1800m. This area extends unitl the a/c reaches 1500ft agl. This area has been surveyed and any obstacles in it are noted, following an engine failure at V1 these obstacles must be cleared by 35ft. If the a/c will not achieve this you must reduce weight or increase VR (runway length permitting) to improve the climb gradient. If the resulting weight is very low it is also possible to fly a procedure that takes the a/c on a flight path that allows the 35ft clearance to be achieved, again this is based on survey data of the area, the max weight that can be lifted will be lower however because as we know on one engine the a/c will climb more slowly during turning flight than wings level. At high weights it probably not possible to turn, climb and accelerate at the same time which why many procedures tell you to ignore accel. height until a certain point during the turn.

It seems to me that there are a few vital implications that come out of the above.

If you do not fly straight ahead you are turning out of the flight path funnel in which your obstacle clearance in assured. You are on your own now, nobody has surveyed the area you are climbing in. You may or may not clear any obstructions that are in the way. 35ft is not much clearance and even in day VMC you will not be able to eyeball it. The rules of course only consider IMC. Outside the funnel something like a power pylon, tall building or gently rising ground could be right in your flighpath and you may not clear it. These obstacles may be present within the funnel but your RTOW will have taken account of them. If you do turn you are also reducing your climb performance and it is likely that at high weights you will not achieve the required gradient. If you are flying an obstacle clearance turn then your RTOW will have taken account of the fact that you will not climb as well during the turn.

Engine out performance planning is a very complex subject and just after a engine failure is not the time to start messing with it. In an airline, someone has done the work for you. (not sure what the biz. jet drivers do)

Look out of the window now and imagine an airliner, on one engine, clearing the house next door by 35ft. Scary isn't it, and that would be legal!

So I reckon that unless there is a published engine out turn you MUST climb straight ahead to 1500ft. If you do anything else you are not doing a Perf A. take-off, you are making it up as you go along and may put yourself in a very dangerous situation.

[ 20 July 2001: Message edited by: Max Angle ]

BOAC

20th Jul 2001, 19:06

Tired - quite right! When the old flying boats retired my heart went too!

Max Angle
Remember, 'Perf A' is only a grouping. It does not stipulate 'straight ahead' only, and has factors for turning flight paths.
Boeing (the only one I know well), run climb performance programmes for all SIDs and will tell you whether you will achieve screen height or not engine out. If not, you publish an 'Emergency Turn' (old guy's speak, I guess, for an EOSID!)

As has been said a couple of times above, make sure you KNOW how your company calculate terrain clearance on SID's - and it is a brave and possibly foolish person who makes up their own! I repeat, Perf A considerations do NOT require you to fly only in a straight line!

[ 20 July 2001: Message edited by: BOAC ]

Stan Woolley

20th Jul 2001, 23:23

We have performance that says follow the SID unless there is a turn published.UK JAR operator.

Now,for example, the Dean Cross SID off Edinburgh 06 requires I believe an 8% gradient to 5000 ft, the 25 mile MSA being 3500 to the north where the SID turns.Two miles off the end of 06 is the North Sea, which I know is flat!In a 737 what would you do?

mutt

20th Jul 2001, 23:28

Max Angle,
Straight out departure information is usually based on “Type A” AIP charts, these usually go out to around 12 miles, are you sure that you will get to 1500 feet in this distance???

BOAC,
Boeing build aircraft, they most certainly do not analyze SID departures of any kind! I would be surprised if ANY airline receives takeoff data directly from Boeing! I sincerely suggest that you go talk to your ops people!

In my present drunken state (thank you EI) I’m going to be blunt!!!! You guys (not just the 2 mentioned) are scaring the hell out of ME!!!!!! Nobody really appears to know what route to follow once your engine fails!

I’m off to the pub!

Mutt :)

safety_worker

21st Jul 2001, 00:11

Max angle - I don't agree with your items 1 and 2. However I agree with your choice of 2, though not entirely! :D

Here are some technical extracts from DOC 8168 in the Jeppesen, ATC Chapter: Departure Procedures - page 202 -
"A departure procedure will be established for each runway where instrument departures are expected to be used and will define a departure procedure for the various categories of aircraft based on ALL-ENGINE 'procedure design gradient' (PDG) of 3.3% or an increased PDG if required to achieve minimum obstacle clearance.
NOTE: Development of contingency procedures is the responsibility of the operator.
Unless otherwise promulgated, a PDG of 3.3% is ASSUMED."

Regarding Missed Approach Procedures-page217-

"Normally procedures are based on a nominal missed approach climb gradient of 2.5%."
"It is emphasized that the missed approach procedure which is based on the nominal climb gradient of 2.5% CANNOT be used by ALL aeroplanes when operating at or near Max Certificated Gross Mass and ENGINE OUT CONDITIONS. The operation of such aeroplanes needs SPECIAL CONSIDERATION at aerodromes which are critical due to obstacles on the missed approach area and MAY result in a SPECIAL PROCEDURE being established with a possible INCREASE in DA/DH or MDA/MDH"

So figure it out with your operator/state authority. ;)

By the way, an extract from a wonderful book by Dr. Tony Kern's "Flight Discipline" (1998) page 18 - "Jeppesen is a company which merely publishes approaches given to them by the host nations and they are exceedingly clear on this point. In fact they publish a disclaimer stating that they 'do not review or approve the adequacy, reliability, accuracy or safety of the approach procedures they publish"
Real interesting inputs. Thanks all. Still no ATC input. Will ask some and post their 'technical know-how'. :rolleyes:

CAT MAN

21st Jul 2001, 00:13

Slick...point taken I was looking at the failure at Vef case...However in the case where an aircraft,having climbed above the MFRA for that runway and has started on a relevent published SID, or say the published missed approach procedure...now suffers an engine out, and this routing is significantly different from the Vef case or emergency turn case then it is more prudent to continue on the procedure being flown... ;) ;) ;)

safety_worker

21st Jul 2001, 00:21

True TR3. Once you are on the SID an experience an engine failure, it's a totally different ball game. It's up to the pilots to know the safest route out of the 'valley'. Performance-wise one is 'probably' better off than if the failure occured at V1.
As stated earlier, a good 'briefing' covering all possibilities is a necessity towards safety!

safety_worker

21st Jul 2001, 10:12

".....a dozen pilots will come up with a dozen different ideas ...." :eek:
Reading back through the thread, this is exactly the reason why I posted this. The confusion is not acceptable. We should know what our company does, what the regulations are and what safety we are assured. If not we tell the company, and prepare ourselves for the safest course of action.
Hope this thread enlightens all of us and makes us safer. :rolleyes:
Mutt - I am indeed concerned as you. Hope you enjoyed that pint. I am off flying...safe flights to all of you.
:)

Max Angle

21st Jul 2001, 14:41

Mutt,

Sorry if we are scaring you, I'm open to suggestions if you have any, what would you do?. I know exactly what I am going to do if an engine expires and we are both briefed on the plan of action before take-off. 12 miles is enough to reach 1500ft, after which you are on your own anyway so you have to have a plan for that bit. Obstacle turns on runways that need them tend to have taken you away from the high ground but some don't. I seem to remember Zurich was one place where you were not pointing in the correct direction.

BOAC.

I agree that Perf A (or JAR whatever) is just a grouping. It is a grouping whose take-off and climb performance is certified using a set of rules and parmeters that ensure that various safety margins are met, to meet those margins you must operate within the regs. The a/c manufactures do supply take-off performance software and that is what churns out the figures on the specific runways pages in the manuals. As you said Perf A does allow turns in the take-off flight path and these can be entered in the software for places that require obstacle clearance procedures. If the page makes no mention of a turn then these figures will be based on straight ahead not on the SID from the runways, at least in our company and I suspect most others, it's hard to imagine someone keeping all the hundreds of pages updated for SID changes etc.

My first post was a dry look at the regulations, of course normallly you are not at max. weight and not obstacle limited and turning into the SID may be quite safe. You must realise that however that it is very unlikley that the figures you used cover the path you are now following.

Most of the time you will also miss any obstacles by a lot more than 35ft, if you are obstacle limited at max. weight or at reduced thrust you won't have much more than that. You may have less if you have rotated too slowly or have a slight tail wind above the runway that you were unaware of.

As Safety-worker says, a very interesting thread, I hope I never have to put theory into practice.

lets go nads

21st Jul 2001, 15:25

Good stuff this! I think if you do not give careful consideration to every different departure i.e should i fly the sid, or go straight ahead or whatever you could be paying lip service to a companies sops. Just a thought, if the sid gradient happened to be 3.3% and the departure is NOT WAT limited and you know that a 757/767 can achieve 5 % single engine at max landing weight why not do the sid.

Chimbu chuckles

21st Jul 2001, 19:21

Mutt, sorry if I frighten you. On the other hand are you suggesting there is always only one correct flight path?

Those of you flying for airlines should have strict procedures to follow at each port you service, surveyed flight paths.

Those of us in the 'Bizjet' world don't as it would be impossible.

I do my best to ensure that my pilots, some of whom don't have an airline background, know and understand their responsibilities under CAO 20.7.1b and can apply that to the many 'one offs' that we face daily.

We are based in, and fly, the length and breadth of Asia. In the last few months we've operated into and out of Shiraz(Iran), Karachi,Quetta,Dhaka,Chennai,Saigon,Kunming(see previous post),Bangkok,Bali,Bandung(Indonesian mountain valley at night),Colombo,Hanoi,Danang,Minado, Siem Riep(where Angkor Wat is in Cambodia),Kathmandu,Padang and a swag of other places. Some like BKK,HCM are easy but many are surrounded by high terrain and have performance limitations due to high DAs.

Unlike many airline pilots who follow parrot fashion the Company published SOPs for assy considerations with little understanding or thought my guys have to think hard about what they are about to do and come up with a suitable plan of action. The list of ports we operate into enough times to build up some 'corporate knowledge' of is short indeed.

I'm blessed, as CP, with a VERY good group of pilots who allow me the luxury of a good nights sleep no matter where they are heading. One thing I take great pride in is that we hire VERY inexperienced F/Os and they get to see an airline standard Bizjet op in and out of VERY interesting ports in all sorts of weather, day/night,high terrain,poor ATC(sometimes) and as a result won't develope into automatons but rather really understand what they are doing and have a flexible approach to staying out of the trees/someones living room.

Chuck.

Slick

21st Jul 2001, 22:46

Muttley, don't be scared me old mate, nobody wants to hurt you.

Nobody really appears to know what route to follow once your engine fails.

Sure they do, name an airport an airplane and lets see what happens ! (europe and a twin fan might be a good place to start)

Best Rgds

Can't work this quote thing.

[ 21 July 2001: Message edited by: Slick ]

Max Angle

21st Jul 2001, 22:49

Chimbu chuckles,

Thanks for the view from another side of the biz. I think this thread shows that some at least, on the airline side of life are more than willing to question and if needed, modify our company procedures to produce what we think is a safe operation. One poster said that we were "scaring" him, but at least we are keen and interested enough to be having the debate at all. Most of our colleagues, I suspect, have not given it a second thought. I for one am very happy to have this kind of discussion and hopefully I will learn from it and take something onboard that will help me one day. Roll on PPruNE!

[ 21 July 2001: Message edited by: Max Angle ]

BOAC

22nd Jul 2001, 00:46

Mutt, I too hope you enjoyed your units!

To state that Boeing just 'build aircraft' is to denigrate a large part of the service they provide. Boeing do provide an analysis of take-off performance for any runway if you pay and there is performance info. available to enable any operator to check each SID route for terrain clearance and work out emergency turns/EOSIDs if required.

I say again, know how your ops dept calculate this, and follow the procedures unless you have a VERY good reason for not doing so. The thought of people 'spearing off' straight ahead because it seemed like a good idea at the time fills me with fear too.

The really difficult ones are where you have NO published performance data or SIDs and there that=airmanship.

Stan Woolley

22nd Jul 2001, 02:10

BOAC

OK see my post above, I believe you fly 737's, can yours climb at 8% single engine at 50 tons,Flap5?I ask again what would you do?

Capn Laptop

22nd Jul 2001, 11:30

Last Sector Power, You want to hope that they DO fly straight ahead if there is no published escape procedure.

When calculating takeoff weight charts, it is necessary to assess all the obstacles within the takeoff flight path.

As there may be many SIDS, all turning in different directions, it is normal practice to look at the straight ahead flight path, and if that becomes uneconomic because of terrain, then design a turn.

Turns are a pain because you need to assess radaii of turn at different speed/flap configurations, where straight ahead procedures are not speed dependent.

So - in the event of a failure on the runway, follow the escape procedure or if there isn't one, go straight ahead! :confused:

PS for all aeroplanes the analysis needs to be done up to the LSA/MSA not 1500 ft,

12nm is nowhere near enough to get to 1500 ft if the aircraft is performing at NETT. ie 1.6% for a twin.

A twin performing at nett (which is all you are guaranteed!) will climb at 97 ft per nm. A 4 engine aircraft climbing at nett will climb 121 ft per nm.

So for a twin to reach 1500 ft (assuming that the terrain underneath is not rising) it will consume 15.5 track miles.

I look out to 30 nm when I run an analysis, using type A's, topos etc

:eek:

[ 22 July 2001: Message edited by: Capn Laptop ]

safety_worker

22nd Jul 2001, 12:43

Capn Laptop - Hear! Hear!
I couldn't agree with you more.
The perf dept must consider a range of speeds (different fleets), obstacles (determine a corridor width), state the bank angles(15deg/20deg depending on the height and position), etc, etc,. This is important to creating a 'Standard' for the 'Company' (helps cross fleet training safety).
What we must do is to spread this knowledge to all pilots. The last thing one needs is to get into the cockpit and have to explain it all, during the preflight briefing, to a colleague who doesn't 'know it'. So get the company's performance department and the fleets rattled to issue the 'knowhow and the procedures' to fly the departure on an engine failure (doesn't matter how many engined aircraft it is - it should be a standard for the company).
Speaking to ATC in the middle east, all they want to hear, if you are NOT flying their departure instructions, is a 'MAYDAY' or a 'PAN PAN PAN'. It will put them on their toes and they follow a checklist. Here the traffic is not too bad most of the time, except at dusk. Wonder what the European(LHR,CDG,FRA,etc,)/American (Chicago, DFW, LAX etc) ATCs .....think...or...do!
Chimbu Chuckles? Wonder what they think/do in the Far East?.... and Africa?
I wonder if the checklist for ATC is the same the world over, or do they, too, have different opinions as this thread (well we are now enlightened)?
We need to spread this subject with all pilots/concerned personnel, in our companies. We might fly with them one day, OR we might fly with them one day...(in the back!!! :eek: )

Crossunder

22nd Jul 2001, 16:11

To reply to the original question; which flight path would I follow?
Well, I would follow the fligh path that would ensure obstacle clearance (you know, the one you are supposed to calculate before take-off...). You are not allowed to take off unless:
a) You are able to follow the SID (after an engine failure at Vef)
b) You (your Company) have made a contingency (emergency) procedure which ensures obstacle clearance.
It is as simple as that! And as for the Class A climb gradient requirements; they have nothing to do with obstacle clearance, they shall merely ensure a minimum of manoeuvring capability during climbout. You guys must distinguish between certification and real-life operations.
And as for that fly straight ahead bull****; what the h*** is that? If you do not have an approved engine failure procedure at hand, then why the hell are you taking off in the first place??? Flying IMC below the MSA without following published procedures is irresponsible and I hope I will never have to fly with any of you "straight-ahead"-guys!

safety_worker

22nd Jul 2001, 16:25

Crossunder - the engine failure 'on takeoff' could be out of an airport on an island, Male, Maldives. Straight ahead would be ok, no obstacles.
Straight ahead, is okay, provided obstacles are studied within the are as dictated by norms laid down for obstacle clearances/establishing an emergency turn.
What are your company's 'rules/norms' for calculating obstacle clearances regarding an 'engine failure on a twin'?
Bob ... wouldn't happen to be Lt. Col. Hammond?

Crossunder

22nd Jul 2001, 16:46

Regarding the island departure; of course the straight ahead procedure could be used, but then this would have to be stated on the plate / in the company's SOP. What I am trying to say is that it isn't up to the pilot right there and then to decide what to do in the event of an engine failure, it must be carefully calculated beforehand in the form of an approved / published procedure.

Where I fly, the pilots don't have to think about it bacause the Flight Support department have issued engine failure procedures (plates) for every AD we use. We just study these before taking off...

safety_worker

22nd Jul 2001, 23:27

Crossunder - 'xackerley! That's the way it should be. Every pilot should know the safest course at all times - situational awareness you say? (not only in this situation - call it mission planning for the whole flight) ;)
Do all airlines/operators have this Engine Failure Porcedure for the airfield before their pilots step into a cockpit? :(
Regulations say (imply by covering their rears) we should!
No 'one' policy for different airlines out of the same airport exists. But as long as it's safe, and taught, and briefed,.....and exists, that's my concern w.r.t. thread.
I feel much better with the thoughts this thread has provoked. Still..... :eek:

Mr Benn

23rd Jul 2001, 00:31

Have just read through 4 pages of this thread.
Surely it is not as confusing as you are all making it?
Personally I would say this.

We are talking about an early engine failure case here.

*If my company has a published Emeregency Turn procedure, I will follow it.
*If it does not I will do what I briefed.
*What I brief depends on the airport and what surrounds it, terrain wise.
*If I have an engine failure I am going to declare a mayday and can therefore go where I like. I will however tell ATC so they can move others out of my way.
* I will remain responsible for terrain clearance.
*In an emergency, noise abatement procedures can be ignored.
*If I was planning on going straight ahead then that is what I would brief. If there was any terrain ahead then I would brief that.
Surely everyone does that?

You look at the plate, you see what is around, you work out what you are going to do in an engine failure case and you brief it?

Why the confusion? Some people posting here sound like they only brief "straight ahead" or "emergency turn" procedures.

Surely good airmanship means you would say more than just "I will fly straight ahead"?

I would normally brief something like
"if we have an engine failure I will climb straight ahead to MSA (state), then I will ask for radar vectors back to the airport for an ILS (or whatever) approach. If we have more time or we require more time I will fly to XXX navaid and take up the hold".

What is so confusing? Its an emergency, we do what we need to and what we want to to ensure the aircraft remains safe. And we brief it in advance to avoid any confusion.

Or am I missing the point here?

Speedbird252

23rd Jul 2001, 02:43

Mr Benn calls it correct me thinks.

There are bound to be variations to this, but it must surely be close to the norm, noise and terrain permitting? :confused:

NorthernSky

23rd Jul 2001, 02:51

Now, I've put the sunglasses on :cool: which means (a) I'm confident of what I'm about to say, though with the caveat that it applies to UK CAA/JAA operators and the requirements placed thereon, and (b) if you disagree, your glaring red faces won't upset me too much.....

First, may I say I'm astounded at the lack of knowledge and awareness displayed relating to this issue. Nothing personal, but Crossunder's post above illustrates my point very clearly.

In general terms, an aircraft commander must know he can make a flight safely. It is only in those terms that Crossunder's comments make sense. However, the regulatory authorities are responsible, again in very general terms, for creating the information environment, and they have not seen fit to provide or require sufficient data to make other than an extremely cursory analysis of the terrain around airports.

First FACT: If there is no emergency turn, then the NTOFP takes you safely straight ahead off the runway to 1500ft and 25nm. In those 25nm you will normally plan to make MSA, and achieve this. Perf A guarantees that the Nett aircraft will be safe.

Second FACT: No aircraft performance data (that I have seen or worked with) analyses SIDs for terrain. Why should they? SIDs are written to get an aircraft from one place to another expeditously, in a manner which suits local ATC requirements, and minimises noise nuisance. SIDs are not of interest to most performance planners, and many seem to pay no heed to them at all. Indeed, one performance provider often says 'Follow the SID' for engine failure in cases where the SID takes you sraight towards the mountains (the performance provider's name is hard to spell, and the airfields involved are coastal Mediterranean). If you doubt this, ask yourself what you would do if you arrive at work and there is a temporary change to a SID - and your performance data does not reflect this change, or when (almost everyday) your departure instructions are to deviate from the SID track and fly a heading. Can you not, then take off, if you cannot fly the precious SID?

The reason for the lack of terrain analysis in SIDs is that (i) the terrain information is not available other than in some instances at great cost and in a format which makes manipulation difficult and (ii) by the time you start to throw in turn performance, raw data navigational accuracy, wind effects, and so on, the calculations become too difficult and vague to be of value, and thus would often be very limiting.

So, that is the performance-related case for following the EOSID or emergency turn (basically the same thing only different), or going straight ahead where no other procedure exists. Of course, as commander, you may do what you like, but if you clang into the hill, you'll carry the can.....

Now, why shouldn't you follow the SID? Well, first, we have seen that there's no assurance of terrain separation. Second, some SIDs involve turns very soon after take-off. Even in an acceptably modern aircraft, engaging the autopilots and executing ENG OUT in the FMC will leave you with drills to do and high workload while you monitor what the aircraft does. In the small Seattle product, do you want to be flying a forty degree turn manually at five hundred feet after take off with an engine on fire and failing while trying to carry out the appropriate drills and keep an eye on your colleague? I don't believe that's a sensible option.

Finally, there is some confusion in relation to ICAO document 8168 and what it says on this issue. Without my copy to hand, I recall that this document says you should follow the 'departure route' following a malfunction. This does NOT mean the 'Standard Instrument Departure', but relates to the route you plan to fly.

From the ATC point of view, once you have said 'Pan' or 'Mayday', you tell the controller what you're doing and he'll help you as much as he can. Here, we meet the issue of airspace, and again I cannot see the logic in, for example, deciding to follow a SID which takes you towards very busy airspace, in the event of a problem. So, brief staright ahead until at a safe altitude (not necessarily MSA; the radar controller will have a much, much lower, safe vectoring altitude which he can tell you about).

Remember the KISS principle: Keep It Simple and Safe.

I do believe, however, that this thread should be compulsory reading for performance departments and Chief Pilots. It illustrates how many are operating in the dark......

:eek:

mutt

23rd Jul 2001, 13:05

NothernSky,

Very interesting post, can i just ask you where you intend to find the obstacle data which covers up to 25 nms from the end of the runway?

Mutt.

safety_worker

23rd Jul 2001, 16:56

Nothernsky - illuminating. Precisely the reason I started this thread, so colleagues/fellow aviators could become safer.
Mutt - I am not sure, but here are a variety of places - Appch Plates, State/Airport authorities, topographical charts, Jepp's database? Municipalities around the airport, etc.
Basically, if one really wants, go out there and find out the best you can. If you believe you have, create the EOSID/ET. If you come across a newly erected obstacle, revise the EOSID immediately and NOTAM it.

john_tullamarine

23rd Jul 2001, 23:23

safety_worker,

I disagree quite strongly.

Either you address the whole takeoff .. or why bother worrying about any of it ? And the task need not be terribly difficult. We don't want to have a multiplicity of departures. All that is needed is for the ops eng guys to check if the normal path is ok with a failure anywhere along it. If not, then ALL takeoffs can be routed via the V1 OEI escape path.

It is most definitely inappropriate to assign this task to the pilot on the day .. he doesn't have the data and never has the time.

Max Angle,

The Type A data is fine, but of limited use ...

(a) it doesn't go far enough ... 1500 ft can be 40-plus miles out for a twin..
(b) many operators schedule turning flight paths for the very reason that the Type A path is too commercially restrictive because of the rocky bits ...

The 35 foot clearance is above the NFP so the expected clearance to the aircraft's GFP will be substantially in excess of this, and increasing, once you are on your way ...

Again, I would commend people to question their ops eng support people to find out what is and is not included in the specific runway analyses. And this can vary quite significantly from one organisation to another ..

Chimbu chuckles,

For most runways, there will be a multiplicity of potential escape paths.. the task of the ops engineer is to find that which gives the maximum RTOW while keeping the procedure itself reasonably reasonable for the poor guy trying to fly it. Of course, for some runways, there will, indeed, only be the one usable escape.

NorthernSky

I am afraid, dear colleague, that some of your views are the stuff of wishful thinking and fairytales...

For many runways, it is totally unreasonable to expect the pilots to have any reasonable way of addressing the NFP clearance requirements... it is the job of the ops engineers (or backroom pilots who know the ropes) who have the performance data .. and should have the best likelihood of sourcing obstacle data .. and it is this latter task which is the hard bit .. doing the sums is, by comparison, child's play.... (sorry, Mutt, monkey's play)

Where do you get the obstacle data ..? .. from wherever you can.. including throwing a theodolite over the shoulder and going bush if necessary .. the advent of satellite imagery data becoming commercially available makes the task a lot, lot easier .....

Guys and gals .... from the viewpoint of an old (conservative) performance (amongst other strange interests) engineer, airline pilot, and instructor pilot ... the underlying attitudes, wishful thinking, and unfortunate ignorance displayed in this thread is quite terrifyingly alarming.

The task is not easy in most cases .... but, please .... quiz your ops eng support people so that you KNOW what the story is .. then work out where you are intending to go after the concrete bit ends .... it is NOT a case of just going straight ahead .. or following this SID or that ... or any other far fetched idea .... if you don't know .. then you are playing Russian roulette with your aeroplane .....

.. and the simplest trick to give you a reasonable chance if you are not ABSOLUTELY sure that the terrain is benign, and you know that your ops eng people haven't looked at it ? ..... decline the SID and follow the V1 escape procedure for ALL departures, setting course once you are above the sector minima. This might be the stuff of ruffling feathers ... but the alternative is the old ostrich head in the sand approach .....

NorthernSky

24th Jul 2001, 01:50

John,

I enjoy the majority of your posts here, and am glad that you aren't afraid to put forward your views.

However, I think you missed the thrust of my post above.

Regarding pilot responsibility. I was saying, in rather more words, that because there is so little data available, and so little of it is accessible to pilots, an effective analysis is very difficult. We make a 'best guess' at each take-off as to the preferable way out of trouble, the same way we make many other professional judgements.

Regrettably, these matters cannot be as precise as you seem to suggest they should, that this is so is addressed within macro risk asessment.

Moreover, you echo my remarks about the paucity of terrain data. Some of it may be commercially available, but not all. That is why in the majority of cases the NTOFP which goes straight ahead is safe!!!

I object most strongly to airlines whose training departments blithely say 'follow the SID' when their performance is sourced from providers who clearly have not and cannot know whether the SID is terrain safe, but do know that going straight ahead is safe. Worst, I have a feeling that some of this is macho clap-trap driven by the belief that climbing straight ahead when you're in trouble is simply too easy.

Yes, some of the sums post-theodolite-trek may be simple enough, but they are still likely to result in low RTOWs, lower than those assuming a sraight-ahead climb or a simple emergency turn. It's also worth wondering why an airline would want to spend a fortune on assessing lots of terrain around lots of airports when the staright ahead/emergency turn data is already available...?

So, 'dear colleague', I think we are singing from the same hymn-sheet.

I'm glad I had those sunglasses on!

:cool:

safety_worker

24th Jul 2001, 08:05

The purpose of this thread was to make pilots aware that:-
1. Their Flight Ops Support may 'not' have calculated their takeoff performance correctly. Ask them, satisfy your curiosity, make yourself safer, by knowing/making them know!
2. The SID, in an engine failure situation, 'may' not guarantee obstacle clearance/be the safest route (they don't HAVE to fly it) and ATC doesn't mind us deviating from it (just tell them)
3. Have a safety route out, no matter where you are in the SID.
I have colleagues who are sceptics about EOSIDs/ETs when a SID is issued by ATC, and I am sure all contributors to this thread has made a lot out there think, fly safer.
Their concern is that ATC would get 'upset' in a busy area like LHR, FRA, if we deviate from the SID.
LOL (no laughing matter)- Fly Safe, Engine failure call a mayday, fly safe the way it's stated (straight ahead, EOSID/ET, etc.) the way it was briefed.

Do all Airbus pilots know what their EOSIDs are in their FMGS? Check with your concerned depts!
Ta all.

[ 24 July 2001: Message edited by: safety_worker ]

Capn Laptop

24th Jul 2001, 08:29

There is obviously much confusion about this topic.

1. Pilots are NOT able to make assessments regarding obstacle clearance on the day - unless you are flying out over the water, the pilot does not have all the required data to hand (PS I am a Pilot)

2. If there is a runway specific RTOW chart, it should have been produced from obstacle data that looks out as far as is required to reach the LSA/MSA.

3. If there is a Runway specific RTOW chart, the weight that it produces is ONLY valid if you follow the flight path that was used to assess the obstacles, AND accelerate at the Acceleration Height nominated on the RTOW chart.

4. If someone has gone to the trouble of producing a RTOW chart, they will first look at a straight ahead flight path (cause it is easier) and if that doesn't produce an economically reasonable uplift, they will look for a turning procedure.

5. It is normal practice to NOT annotate the RTOW chart with a procedure UNLESS it is has turn - so if there is no specific instruction on tracking, assume straight ahead.

6. If you don't follow the flight path described (either straight ahead or curved as appropriate) you may as well not have bothered looking at the RTOW chart - cause the numbers are MEANINGLESS!

7. If you choose to ignore the acceleration height on the RTOW chart, and decide to extend the 2nd segment, you may as well not have bothered looking at the chart either - cause you have gone outside the conditions used to produce the weights on the chart. - and don't think that because there is terrain higher than the acceleration height in the extended flight path, that it hasn't been considered, you will probably find that the RTOW programme wants to accelerate the aircraft early, clean up, and then clear the obstacle in a clean configuration - mostly for 5 min eng limit considerations....

There endeth the lesson..

PS, We spend heaps and heaps of hours pouring over type A's, topo's etc, designing procedures, identifying obstacles etc, and whilst I can't speak for others, I go to great lengths to ensure that the RTOW charts and associated procedures I publish for the crews in ther airlines that I have worked, are safe, and easy to fly. :confused:

NorthernSky

24th Jul 2001, 11:11

Laptop,

I agree with almost everything you say, but would be interested to know what your evidence is for point (2)?

To my mind, by the way, RTOW charts deal with runway limits as well as with obstacle problems, so checking them is still valid even if you intend to deviate from the chosen route (this would normally be done approaching MSA on all engines, having decided it's safe to route direct to somewhere assuming terrain will be cleared even with a malfunction. Purists will note, correctly, that this is a grey area.

safety_worker

24th Jul 2001, 14:25

We all seem to be speaking the same language, with different accents?
1. No one is asking pilots to assess obstacle clearances. They should make sure that they have a flight ops perf centre that does. Find out what criteria they use. Pilots should follow their SOP procedure laid down. If you don't find it safe or correct, change it!
2. Obviously the RTOW will have the most restrictive obstacles considered stated on the chart, and if necessary the EOSID/ET will be stated - if you can't go straight ahead (distance equated to 10mins?)
3.RTOW charts have acceleration heights. The same as for the ET/EOSID, or, it may have a point (fix) if a turn is a factor (at V2 - V2+15, or whatever speed the norm dictates) that will have to be followed. ( sometimes you might have achieved your min ht for accel, but haven't got to the point for the turn on the EOSID/ET)
4. 10min eng limitations are also used, aren't they in your perf?

BOAC

24th Jul 2001, 15:58

Flanker - sorry to be awhile replying, I've been away. Its a while since I EDI'd, but I think from memory our ET for R06 is ................ out to sea and I would follow it, to answer your question, because it has been researched.

There seem to be a lot of people here who are prepared to make up their own procedures. That is extremely unwise. Required climb gradient is easily available for all SIDs; manufacturers will tell you what climb gradient you will achieve on the flight path selected, engine out; thus the need for an 'escape route' can be determined. If you do not like your company's procedures or do not understand them, do something about it! The ice is extremely thin if you start changing your mind on the day or 'doing your own thing'.

safety_worker

24th Jul 2001, 17:29

BOAC, NothernS, JackT - well said and posted.
Ta All. :)
Can smile a bit now!

safety_worker

24th Jul 2001, 17:39

Just got this dug out -
Assuming engine failure at V1 and maintaining V2 or not exceeding V2+15 (TAS of say 170KTS) for a given weight/wind/temp, the distance that can be covered in 10 minutes would be (170/60)x 10 = 28NM
This is the obstacle range considered for 'straight ahead'. If we can't meet it we construct an ET/EOSID.
We consider obstacles in the takeoff path for both straight ahead and whenever there is a turn requirement.
We consider obstacles from end of runway along the Engine Failure Procedure(EFP) path up to the approach fix or holding point.
We have EFP on all runways, either standard (straight ahead) or non-standard EFPs (ET/EOSID).
What do you have?
An engine failure once established in the SID, is something the 'pilot(s)' should be prepared for...until enroute MSA (say)?

Cough

25th Jul 2001, 02:27

Very interesting....My feelings are to follow the Emergency Turn, or if none published, the SID (not straight out). Why?

Because it is our SOP. Published in writing in the big book of our roolz and regs.

Secondly, I know that our operator checks terrain clearance out on SID's that we use. It does not check terrain on SIDS that we do not use. Hence, if you invent a procedure relevant to you, maybe for good reason, a class #1 diamond geezer hasn't done his sums on your behalf. If should something happen you will open a can of worms for yourself when you could be Mr Cool in the Bar instead.

By the way - Emerg turn EDI 06 (737) - Track 070 and turn once you are happy to do so (i.e. above MSA)

Just spent 2p. £1.98 to go - I'm skint this month. Pilot (Baby!)

[ 24 July 2001: Message edited by: Cough ]

mutt

27th Jul 2001, 01:16

I’m slowly dragging my arse back to semi civilization, but COUGH are you telling us that your takeoff weight is based on the worst case SID?

Mutt :)

mutt

27th Jul 2001, 02:32

Guys, I have to explain one thing, It isn’t you hurting me, it’s me hurting you!!!!!!! Because I’m the guy who sits in an office and decides what path I expect you to follow!
Needless to say for the 100 or so aircraft that we operate, it most certainly isn’t the SID!

You may think that your airline is different, but I could name at least 15 major airlines that share our procedures!

BOAC has stated that Boeing checks all SIDS!!!!!!!!! Nope, this most certainly isn’t true. Mainly because MOST of us cant afford their RATES! I would love to know of ANY airline that was actually getting this level of support!

What Boeing does supply is a takeoff program based on either the Mark7 program logic or SCAP logic; it most certainly doesn’t follow SI Departures. (Airbus is different and has introduced a Flight Path Program this year, which I know very little about)

So guys and gals, its simple!

If there is an engine failure takeoff published, follow IT.

If not go straight ahead and start yelling to ATC!

DON’T FOLLOW THE SID……… unless of course you happen to work for an airline that states….”takeoff weight based on SIDXX departure”.

Have fun now…….

Mutt :)

BTW, tomorrow we are heading south east from GVA on a SID (B777) which we have problems achieving on TWO engines! Needless to say if we based this departure on an engine failure, we wouldn’t even takeoff!

safety_worker

27th Jul 2001, 06:50

Cough ...just curious. What's the MSA for EDI06? How far is straight ahead?
Why is your perf calculator checking SIDs?
Don't you think he should be checking airfield obstacles instead :confused: rather than which SIDs will clear obstacles (single engine?) and which won't! What does he do when he finds a SID that won't clear obstacles (SEngine) :eek: ?
SIDs change, obstacles 'tend' to remain where they are.....unless they are blown up, blown away, removed..
Just curious all, how about posting your Engine Failure Flight Path definitions (when does your company find it necessary to introduce an ET)
Are your ETs in your FMGS as EOSIDs?
Ta.

BOAC

27th Jul 2001, 09:36

Mutt, what I said (21/7 and 24/7) was that performance info is available for operators to check ANY SID. In my case provided by Boeing and published SID required gradient. The company I am with DO check all SIDs, incidentally, Cough, you never know whether you may have to fly one!

I think we are talking the same language really! SE from GVA? Don't think I have flown it, but I guess it has min en-route altitudes published, and I hope you have SOPs which tell you what to do if you do not achieve these, and that you brief and fly them! Surely any operator would take into account any terrain avoidance turns before accel is complete in the RTOW figures, and this info is also available? Naturally individual SIDs are not catered for in RTOW charts, (unless there is a 'common' obstacle avoidance turn on all deps), but ETs cover these.

SW, RTOW handles local obstructions, doesn't it? Once clean and climbing away on a departure, achievable climb gradient is the key. If you cannot achieve it go somewhere else, but I DO suggest you go where your perf. dept suggest. They will know more than you.

Cough

27th Jul 2001, 13:56

mutt - Yup. But given any sort of restriction I guess that the company would prefer to publish an emergency turn than suffer any sort of restriction.

Safety Worker - The general MSA out of EDI is 4.6 for us, BUT the more dominant 25nm MSA is much lower (I seem to remember 3.4 in the NE sector & 3.8 overall?) and that would be far more relevant.

Got to remember that our ops manual states that we MUST fly the SID in the absence of an emerg.turn. So that is what we do!

737 - We have no EOSID's in the FMC - Think that this is a Airbus thang! So when we need to we hit the button 'heading' and steer!

Cough

27th Jul 2001, 14:02

Safety Worker - GVA

05 Climb to SPR and hold.
23 Turn L to SPR (with speed restriction until turn complete) and hold.

Complete the SID single engine - Not on ure nelly! Bear in mind we have A LOT of ET's published!

john_tullamarine

30th Jul 2001, 02:38

Sorry to be a little tardy in wading back in, chaps ... only just organised myself a new ISP hookup in the current transient locale ....

Northern Sky,

We are, indeed, of similar accord. The sums are pretty straight forward if the operator bothers to spend a little effort on the problem ... what is needed is for the flightcrews to jump up and down a bit more to get some action. Making a call at the time is fine .. but it doesn't win any points in court after the prang ... quite the reverse... which is why I exhort people to read some relevant transcripts .. all quite sobering.

If the turn doesn't give you extra weight, then you won't be turning .. the operator will be doing something else .. sometimes even going straight ahead. However, if the straight flight path is not optimum for RTOW, then one looks for a more useful turning escape path (read "more payload").

Capn Laptop,

One of the problems is that some operators and service providers most certainly don't worry about the latter parts of the initial climb.

Safety_Worker,

One ought not to forget the 4th segment as well .... for a twin ... 40-odd miles under limiting conditions is a good figure in the back of the mind ...

Mutt, old mate, ought we to consider running a symposium on the general subject of terrifying takeoffs ?

411A

30th Jul 2001, 06:48

If you should ever takeoff from runway 23 in GVA and turn left, the word terrain has a whole new meaning. In the TriStar, used to hold at the PAS NDB until FL140 before proceeding SE bound. :eek:
Mutt, you may be interested to know that the procedures at your airline (follow EO turn or straight ahead, not SID) have remained unchanged from 1979.

mutt

30th Jul 2001, 07:40

411A,
Yep that sounds like the procedure that we just removed. The 777 is capable of meeting the SID requirements on two engines provided that the weight is 240,000 kgs or below. (MTOW 286,000 kgs) otherwise they get a spin around the hold.

J_T,
Actually idea, we could make a fortune!

Safety_worker,
If you are in EK/DXB, go chat with the Frenchman in your Operational Engineering department.

Mutt. :)

john_tullamarine

30th Jul 2001, 13:04

Mutt, mate, is that fortune referring to before or after the bar sessions ... sorry post-seminar think tanks ?

..seriously .. how do we convince a few of our colleagues that the square-jawed Brick Bradford type is not really what it is all about ?

[ 30 July 2001: Message edited by: john_tullamarine ]

4dogs

30th Jul 2001, 19:01

Folks,

Some relevant reading:
http://www.casa.gov.au/manuals/regulate/aocm/011r0614.pdf
http://www.casa.gov.au/manuals/regulate/aocm/011r0718.pdf
http://www.casa.gov.au/manuals/regulate/aocm/form144.pdf
http://www.casa.gov.au/manuals/regulate/aocm/form860.pdf

I have quoted these because the Australian contributors are talking about life under CAO 20.7.1B which, unlike most international standards, demands full accountability essentially from chock to chock. The take-off splay does not truncate but continues to expand (to cater for dinosaur aeroplanes in real wind) until the aircraft reaches MSA/LSA. As this is OEI, many of the considerations that eventually result in the RTOW may be far from obvious to the crew and hence they are actively discouraged from deviating from the one true path- ie the flight path that has been analysed as producing max payload!!

For those of you out there who are not legally required to be provided with the sort of data to which we are referring - best of luck. Dare I suggest that those of you who are mesmerised several times a day by the awesome AEO performance of your machines need to get a grip on how different life is when you are hot, heavy and OEI. You may well spend your whole life never having to face the reality of an engine failure - I do hope so - but don't be caught short because you didn't understand.

safety_worker

31st Jul 2001, 09:14

"seriously .. how do we convince a few of our colleagues that the square-jawed Brick Bradford type is not really what it is all about ?"
J_T - that's why I started this thread. Hoping! :(
Ta all for the inputs.
Ta Richard for the sites.
4th segment? 40Nm? Hmmm! Back to the Perf man. ;)

john_tullamarine

31st Jul 2001, 09:50

Richard,

One of the problems is that some operators in the Antipodes, and elsewhere, pay only lip service to the regulatory intent.

From my viewpoint, regardless of jurisdiction and local requirement... it is somewhat pointless to worry only about part(s) of the flight when the critical situation, on a given occasion, may well be during the bit which is ignored.

On another point, the Australian regulator has some practical difficulty in that the organisation is not well off for operations engineering experience. I can bring to mind only one person who has had airline experience, two others with a sensibly reasonable background, and another two who have the basics under control. This makes it very difficult for the flying types in the organisation to administer the regulations when they don't always have rapid and direct access to practical competence for the necessary backup to control some elements in the industry .. especially when several of the above people work in unrelated areas ..

I concur heartily with your observation that impressive AEO performance, allied with little outside the simulator exposure, does tend to give the average pilot a trust in his/her aeroplane's capabilities which might not be entirely justified. This is, of course, most pronounced in the two-motor models ..

safety_worker,

Peace, brother ... I know that .. and we are of one accord.

.. 4th segment ? ...Many pilots blythely look at second segment matters and forget that

(a) off a shorter runway, the first segment can often be very limiting with respect to obstacles in the early climb .. or even an uphill terrain slope ..

(b) for a jet, the third segment acceleration phase can go on for a long distance due to the big speed split between second and fourth segment climb

(c) fourth segment climb is hardly the stuff of the US space program ...

Now, we are all comfortable with the gross to nett idea .. but, throw in a little turbulence with the failure .. and see how the comfort zone squeezes up real tight ... or rather worse ..

Two observations ..

(a) under reasonable limiting conditions, it can take a LONG time and distance to get to LSA/MSA, or even just above the local terrain ..

(b) if a pilot doesn't quite know the details of what is out there ..and the ops eng support is a bit thin, then, consistent with the specific terrain, it might be a good idea to look at turning back toward the aerodrome so that, at the very least, the plate data can give some comfort ... mind you, that doesn't always work .. I have seen the occasional plate where navaid data blocks inadvertantly have been placed in a neat and eye-catching manner on top of the critical terrain data ...