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Engine Failure on Takeoff! Flight Path?

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Engine Failure on Takeoff! Flight Path?

Old 16th Jul 2001, 22:44
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Question Engine Failure on Takeoff! Flight Path?

This is for Pilots and ATC's. I've been flying all over the world and have come across this subject with varying opinions. So I thought I'd put it across:
After experiencing an Engine Failure on Takeoff (obviously after V1), what flight path would you fly?
Consider been given a SID! Consider obstacle clearances, Takeoff thrust limitations, performance gradients, etc.!
What does ATC expect?
Could postings contain identification of profession, such as Pilot/ATC please
Thanks!
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Old 17th Jul 2001, 01:51
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I'd follow the SID, or emergency turn procedure if there is one. Another good question is if you do a single engine go-around, do you follow the missed approach procedure, or the emergency turn procedure (again if there is one published).
BTW, I'm a pilot.
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Old 17th Jul 2001, 02:03
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There is already a similar thread that answers this question,If one flew a sid after an engine failure on takeoff, then,an airline cockpit is not the place for them. The rules change in these circumstances and a brief look through CAP385 would do no harm...
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Old 17th Jul 2001, 02:09
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Fly the Emergency Turn procedure (even though that may be straight ahead). Emergency turns are company generated procedures so it will be necessary to inform ATC of what you are doing. These procedures take into account all the items you list for that type of aircraft. (Pilot)

Single engine missed approach is to fly the missed approach procedure.

[ 16 July 2001: Message edited by: Jetdriver ]
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Old 17th Jul 2001, 03:03
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We have printed engine failure procedures for all departures. They very seldom follow the SID's, so it's important to notify ATC as soon as possible.
Missed approach with an engine out, we generally follow the missed approach procedure. That is, if the go around was not initiated from below minima, in which case we follow the engine failure procedure.
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Old 17th Jul 2001, 10:01
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Arrow

I believe, SIDs are 'only' for all engine situations (lets consider twins). The gradients are quite high (>3percent). A SID 'may be' the Engine Out SID (operators should verify this considering obstacles). Otherwise, we should fly straight ahead (no obstacles), or, the Emergency turn (EOSID - airbus) - a flight path that has considered obstacles, and adequate clearance is assured (calculated) ONLY on this 'emergency turn' flight path with the engine out!
Yes ATC will have to be informed ASAP (after the aircraft is flying safely under control).
TR3 - know the website for CAP 385?
What does ATC think about this? Varied thoughts there!
Thanks.
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Old 17th Jul 2001, 19:38
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TR3 not sure I entirely agree. Yes SID's are generally drawn based on all the A/C eng's operating, and most specify a min climb gradient. However SID's can also be constructed with noise rather obsticles in mind, and in cirtain cases it may be better to fly a sid with an eng out knowing where you are rather that fly straight ahead IMC. Of course only if there is no emergency turn published.

I think I am correct in saying ATC may not always be aware of emergency turn procedures so advise.

Best Rgds
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Old 17th Jul 2001, 20:25
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Angel

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 !
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Old 17th Jul 2001, 21:06
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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.
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Old 17th Jul 2001, 22:34
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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
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Old 17th Jul 2001, 22:54
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Arrow

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.
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Old 17th Jul 2001, 23:11
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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.
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Old 17th Jul 2001, 23:47
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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
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)
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Old 18th Jul 2001, 01:13
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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.
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Old 18th Jul 2001, 01:17
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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.
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Old 18th Jul 2001, 10:04
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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!
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Old 18th Jul 2001, 11:07
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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.. null
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Old 18th Jul 2001, 11:59
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Talking

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.
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Old 18th Jul 2001, 13:25
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Question

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?)
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.
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Old 18th Jul 2001, 14:07
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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.
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