Emergency turn blues

[bultaco]

Hi all,

could someone please shed some light on the following scenario:

1) Departure with Emergency turn
2) Icing conditions
3) Engine fire occurs after V1 and we get airborne.

Is it ok to fly the Emergency turn procedure at V2 or should some increment be added for icing conditions ?

Also is it ok to complete the memory items and then turn or must the turn be made at 400' ?

its just that if I'm turing carefully with 15 degrees of bank at exactly V2 and the PNF is saying "confirm engine start lever number 1" then I have to look down and it could be dangerous

[5LY]

Your performance calc. has already, in theory, accounted for the conditions. Don't get creative. Fly at V2 plus any extra that you've already achieved within the scope of your a/c manual. If all that you have is V2, then fly at that speed. Trying to accelerate now will almost certainly require level flight. Not a good idea.

Rule number 1 is fly the a/c. If you aren't successful with that the rest doesn't matter. The earliest time to do your recall items is 400 feet. That doesn't mean you have to do them then.

[bultaco]

thanks John and 5LY that answers my question perfectly :)

[john_tullamarine]

Couple of points.

(a) turn will be for terrain (somewhere - does your procedure specify ?) and turn radius often (not always) is a critical design concern. Turn radius links to speed so the starting point for the turn AND the min/max speeds specified for the turn are critical.

(b) "confirm engine start lever number 1" is a training/experience issue for which the appropriate response is something along the lines of "stand by! ". We all started out as newchums originally ..

The procedure should have addressed all the reasonable emergencies. If you are not sure whether or what then run the question past the ops eng folk.

[Mach E Avelli]

You don't state the type, but from reference to engine start lever I am guessing B737.

V2 allows 15 degrees angle of bank, so no additive required unless the emergency turn specifies a greater bank angle.
From memory, Boeing don't require additive to V2 for icing, though some types may require up to 15 knots! Perhaps your performance analysis automatically recomputes V speeds if you key in icing conditions?
As mentioned, Boeing also recommend that if you have achieved a speed greater than V2 when the engine fails, it is acceptable to maintain the higher speed. In any case the climb at or above V2 is to be continued until the emergency turn is complete, even if this results in an altitude greater than minimum for acceleration and flap retract. In other words, even if acceleration is, say 800 feet, and you reach it while you are still turning you do NOT attempt to accelerate at that point. Complete the turn first.

As for buggering around with shutting the engine down in the turn and still at 400 feet, that's for you to sort with your Company SOP. Where I come from we don't commence the fire drill until at least 800 feet. And only for a fire, not any other failure - we leave other failures, even severe vibration - until after flap retract and MCT has been selected.
In the case of fire, the decision of when it is safe to shut it down rests solely with the PIC, and that would not be while hand flying a turn at V2 !
Another consideration with an engine fire is that usually the engine will still be producing useful thrust, which is helping you get away from the ground . Even in the unlikely event that the engine thrust fails totally (e.g. core seizure) and is accompanied instantaneously by a fire warning, the shut down is secondary to controlling the aircraft and clearing obstacles. But I know from your original post that I am preaching to the converted......
Sure, given enough time you can hone a pilot's skills in the simulator to maintain V2 in a perfect 15 degree banked turn, while identifying and monitoring the shut down, but if it happened for real out on the line three or four months later, I would not want to try it down at 400 feet on a dark and dirty night.

[A4]

.....we leave other failures, even severe vibration - until after flap retract and MCT has been selected.

Wow. I'd feel a little uncomfortable with that. Is it the same for surge/stall?

[Skyjob]

The 400' referred to should be used for two things:

The earliest opportunity to turn has been identified aurally by non flying pilot (PNF) to the pilot flying (PF);
In case of no emergency turn, the point at which the PF can call for what malfunction has occurred;

Then, subject to immediate turn considerations and workload, the PF can ask for any memory items / recall actions to be completed by non-flying pilot (PNF). These may include the PF actioning some thrust levers, acknowledging the right engine and memory item to be completed, so for that reason any turn distractions at that point are totally distracting.

A turn may only be required after some distance, in which case it would make sense to complete these actions on the straight climb out part. If an immediate turn is required, this has absolute priority, and the 400' call could be an identifier to turn, so the call for stating malfunction can wait until turn completion.

Once turns have been completed, aircraft is accelerated to flaps up manoeuvring speed, crew have obeyed the thrust limitation (e.g. 5 or 10 minutes subject to operator and type variation) in the manoeuvring process, it's time to do any additional checklist items.

[HazelNuts39]

Part 121 OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS
Subpart I--Airplane Performance Operating Limitations

Sec. 121.189

Airplanes: Turbine engine powered: Takeoff limitations.

(f) For the purposes of this section, it is assumed that the airplane is not banked before reaching a height of 50 feet, as shown by the takeoff path or net takeoff flight path data (as appropriate) in the Airplane Flight Manual, and thereafter that the maximum bank is not more than 15 degrees.

[john_tullamarine]

The 400' referred to should be used for two things:
The earliest opportunity to turn has been identified
Except where the turn starts at runway head .. ie a presumed NFP RL of 50ft ?

... I see that HN has beaten me to the punch .. never mind ...

[FullWings]

I think half the problem with rapid (unthinking?) responses to non-normal situations comes from the format of some simulator checking/training, certainly in the past. The emphasis was on getting recall/memory items done as fast as possible and as it was the same V1 cut/fire every time, it was easy to get into the habit.

Having been exposed to much of the above negative training, I make a conscious effort to a) fly the aeroplane above all else, b) spend as much time as necessary diagnosing what's happening and c) only take action when we are in agreement as a crew about what needs to be done and there is sufficient capacity available to effectively monitor it.

There are very few things that need an immediate response: high speed RTOs and hard GPWSs come to mind - for pretty much everything else there is time for some thought and interaction. When you get an engine fire warning, does it mean that the wing (or wherever the engine is mounted) is a mass of flames? No, it signifies that the temperature inside the nacelle has gone over a pre-defined limit, not an amazingly hot one either. It could be a false warning, although with multiple loop systems, that's unlikely.

My company has 400' as the minimum height to initiate any drills and I emphasise in briefings that it is just that, a minimum, not a target. If it takes us until we're clean (or later) to diagnose the issue(s) and start actions, then that's not a problem. Getting the aeroplane away from the ground, in trim with as much automation in use as possible is the primary goal. After that, making sure that the projected flight path is the one we want, especially when OEI. Only when the previous two conditions have been satisfied is it sensible to start recall items.

[Skyjob]

Obstacle clearance or departure procedures may require a special engine out departure procedure. If an immediate turn is required, initiate the turn at the appropriate altitude (normally at least 400 feet AGL).

My apologies if I made it sound that 400' AGL must be attained, I was referring to the 'normally at least 400 feet AGL' quoted above from the FCTM.

[Mach E Avelli]

Thank you FullWings for putting it so clearly.

A classic case of "rapid unthinking response" followed by the realisation that having right royally fckud up they had better do nothing except fly the aircraft, occurred at Adelaide back in about 1992.

A Bae146 crew were taking off when they spotted a large flock of birds sitting on the runway. PF, perhaps reverting to his fighter pilot days, decided in an instant to attempt to get above them by rotating considerably before V1 had been reached. That resulted in a bad tailscrape, leaving enough shrapnel on the runway for a following B737 crew to report it to the tower.

Immediately they got airborne, and still before V2, they hit several birds, with one engine failing completely and another suffering severe damage and partial loss of thrust. Whether it was a conscious decision then to keep the damaged engine going or not, that was all that saved them. They did no drills (one can only imagine the "oh bugger" moment!); simply concentrated on nursing it around to a successful landing, barely maintaining VMCA. Had they attempted to shut down damaged engine(s) the outcome may not have been successful, as the aircraft was above its two engine inoperative weight and the FDR readout showed it remained within a few knots of becoming uncontrollable for the duration of what was a very short flight.

[Bergerie1]

FullWings


An excellent post. In my experience both as an instructor and line pilot on several different types I agree totally and couldn't have said it more eloquently.

[rudderrudderrat]

Hi FullWings,
When you get an engine fire warning, does it mean that the wing (or wherever the engine is mounted) is a mass of flames? No, it signifies that the temperature inside the nacelle has gone over a pre-defined limit, not an amazingly hot one either.

There have been many examples of serious engine damage / fire which require fuel, hydraulics, and electrics etc. to be isolated before more damage is done. e.g. ASN Aircraft accident Boeing 707-465 G-ARWE London-Heathrow Airport (LHR) (http://aviation-safety.net/database/record.php?id=19680408-0)
"About 1,5 minutes after the start of the fire, No. 2 engine, together with part of its pylon, became detached and fell into a waterfilled gravel pit."
"PROBABLE CAUSE: "The accident resulted from an omission to close the fuel shut off valve when No. 2 engine caught fire following the failure of its No. 5 low pressure compressor wheel."

and:
http://www.blackholes.org.uk/PP/VH-OQA%20fire.jpg
http://www.atsb.gov.au/media/4173625/ao-2010-089_final.pdf
"The electronic centralised aircraft monitoring (ECAM)3 (Figure 1) displayed a message indicating a No. 2 engine turbine overheat warning. ...The first officer also reported observing an ECAM warning of a fire in the No. 2 engine that was displayed for about 1 to 2 seconds, before the ECAM reverted to the overheat warning and reinitiated the 30 second monitoring period."
"1.11.1 No. 2 engine external fire
Following the uncontained engine failure, an external fire developed in the lower left region of the No. 2 engine nacelle. A portion of the thrust reverser assembly was burnt in the fire (Figure 16). Initial on-site inspection identified that the fire was most intense in the lower left thrust reverser section and in the lower bifurcation13 (Figure 17 and 18). Sooting, glazing and the effects of heat were observed on a number of electrical, air, oil and hydraulic supply lines and the nacelle anti-ice bleed air ducts within the core section, lower bifurcation and accessories section (on the fan casing)."

and:
http://www.aaib.gov.uk/cms_resources.cfm?file=/dft_avsafety_pdf_026142.pdf
"No damage was evident externally, however, on opening the No 1 engine cowling there was evidence of significant fire damage centred around the underside of the engine. The fire has resulted in sooting and an oily residue around the outside of the engine casing and damage to wiring. The fuel control unit input rods showed signs of heat damage to the bearings. There was also evidence of penetration from inside the engine casing in the area of the discharge vanes in approximately the 5 o'clock position (viewed from the front). A small piece of debris was found within the cowling. Further examination revealed two penetrations of the engine casing around the 5 and 7 o'clock positions with damage to the oil tank and a ruptured fuel pipe (see Figure 1)."
"There have been previous incidents where LP compressor second stage blade root fractures have resulted in the release of a blade from the disk. In some cases released fragments have penetrated the engine cowl, damaged or severed fuel lines, and caused engine fires within the cowl. The manufacturer's Alert Service Bulletin (ASB) 5729 Rev 2, dated July 8 1988, identified this problem. At that time there had been a total of 115 fractures of second stage fan blade root attachments. Twenty of these resulted in cowl penetration but with no reports of significant aircraft damage. Nine resulted in fires, all of which were extinguished by means of the engine aircraft fire extinguishing systems."

If it takes us until we're clean (or later) to diagnose the issue(s) and start actions, then that's not a problem.
Whilst I agree it is pointless to do an immaculate shut down procedure and subsequently crash into the terrain, it is important to secure the engine in a timely manner. Once the engine is secured, then subsequent actions can be left until you are clean or later.

[Chris Scott]

Hi r-r-r-at,

Am inclined to agree with you. I travelled by road to LHR quite by chance on that day in 1968 (being LGW-based at the time). As I approached the airfield, the black smoke was rising. (Many years later, when I converted from the VC10 to the B707, I was appalled by the ergonomics of the F/E's fuel panel, particularly the lack of any steady indication of LP valve position.)

It's very true that a prematurely-conducted fire drill can lead either to loss of control on the one hand, or the botching of vital actions on the other. However, once the a/c is at a safe height and - in the case concerning this thread - established in a long turn at V2 or above, with a steady 15 deg of bank, the workload of the PF may well permit the vital actions (memory items). It's a question of judgment on the day. You don't want the PF to be asked to confirm the correct engine master switch, for example, when (s)he is due to roll out of the turn.

[rudderrudderrat]

Hi Mach E Avelli,
Whether it was a conscious decision then to keep the damaged engine going or not, that was all that saved them.

This crew over rotated and found themselves airborne but well below V2 for about 60 seconds. They recovered and shut down the damaged engine.
http://www.aaib.gov.uk/cms_resources.cfm?file=/4-1989%20N605PE.pdf

[FullWings]

Whilst I agree it is pointless to do an immaculate shut down procedure and subsequently crash into the terrain, it is important to secure the engine in a timely manner. Once the engine is secured, then subsequent actions can be left until you are clean or later.
I agree with "timely". I certainly wouldn't delay any critical actions once we had agreed on what had happened and what to do about it. What I don't like is hands flashing around the cockpit pulling knobs and levers mere seconds after a warning has appeared. I included the possibility of leaving drills until clean or beyond on the basis that if it is that hard to determine what's going on, the problem is likely pretty complex and it'd be easy to respond inappropriately.

The previously quoted examples were all uncontained engine failures. It's really not your day if that happens - if you're lucky, shutdown drills may work if shrapnel hasn't cut through anything too vital.

From the 1968 BOAC accident:

...when the flight engineer fully retarded the thrust lever; the check pilot and flight-engineer simultaneously went for and pulled the horn cancel switch on the pedestal whilst the co-pilot instinctively but in error pressed the fire bell cancel button. In front of him the flight-engineer went for the engine fire shut-off handle but he did not pull it.
That looks to me rather like a CRM failure with everyone (including an observer) doing their own thing and the captain maxed out flying the aircraft. Knowing what we now know (of which much has been paid for in blood), if they'd slowed down a bit, diagnosed the problem then deliberately executed a monitored fire drill, things *might* have turned out differently. The same thing happened on the ground: most of the evacuation drill didn't get actioned, which didn't help reduce the fatalities...

I suppose what I'm trying to say is that we shouldn't be rushing critical drills close after the event that caused them, especially when near to the ground, force majeure excepted. Equally, leaving problems that will probably get worse to stew for inappropriate lengths of time is not a good idea, either. Somewhere in-between would be best and it is a fairly wide band; I would have thought that most experienced aviators would be reluctant to take action until they had a fairly good idea as to what was wrong and that the action proposed as a remedy was suitable.