S61N Reject after CDP

[wong]

I would like to seek the opinion of other S61N drivers on doing a rejected take off immediately after achieving CDP on an Oblique take off ( CDP 50ft 20 kts) and Ground Cushion (CDP35 kts 20ft) if there is still a lot of runway remaining.. say 5000ft. In our ops manual, our brief for the take off is.."if engine fails after CDP continue the take off and rejoin for landing". It looks ridiculous that with over a mile of runway available and at such low altitude we should risk doing a single engine circuit.The flight manual has a phrase that says.."at CDP after forward input of cyclic no rejects should be attempted.So at the moment, our training cell has verbally told us not to do a Group A take off even though we are within the WAT limit but instead to do a Modified Group A take off (CDP 300ft 45 kts). Any inputs esp by North Sea S61 operators are appreciated.

[212man]

I can't speak about the S61, but in general terms the use of remaining runway for a rejected takeoff is condoned. In fact, part of the OPC briefing stresses that although there may be sufficient runway remaining to reject after TDP, for the purposes of the test the candidate should consider himself (or herself) commited to continuing.

In some ways CDP is a better description of the point as it states it to be a critical decision, rather than the takeoff decision. The inference in the former is that you now have a choice after CDP compared to prior, where with TDP it tends to imply you are commited to continuing in the same way as for fixed wing.

One proviso though is that you are now entering the realms of subjectivity when deciding on your new comittal point. What you consider to be the latest point from which you can still make the runway may not be the same as your colleague's. So there are dangers involved in advocating a reject after CDP.

[stormcloud]

It's a long time since I flew a 61 but 'subjectively' :-

35kts = 3550 feet/min groundspeed so 5000 feet = 1 min 20 secs plus a bit to the end of the runway. Should be plenty of time to react and land if you wanted to in the example you give.
Remember the Garuda DC10 who had an uncontained no 2 fail above V1 and rejected/overran?
Killed a couple of people but arguably saved several hundred!
It's your call on the day, just do it well!

[helmet fire]

I agree with the above comments - although I too am not an S61 pilot - because I think the problem is applicable to all twins. These days we tend to get a bit wrapped around terminology and definitions without considering application.

I'll use the following terms: CDP = Critical Decision Point and infers take off , LDP = Landing Decision Point.

The critical areas of the decision points are exactly opposite, i.e. before LDP you have a choice, AFTER LDP you are committed, whereas BEFORE CDP you are committed, and after CDP you have a choice. Forcing you to go around rather than reject after CDP is removing the flexibility of the concept. It is akin to forcing you to commit to landing before LDP!!

Please forgive me for suggesting this wong but if your ops manual "tells" you that you have to go around then either
1) Your management needs to revisit the concept of CDP/LDP because they have missed the inherent flexibility of the terms, or
2) They have mandated this in an attempt to cover their own backsides by removing a possible judgement call from your hands.

A way around this? Failure after CDP, convert to the pre LDP approach so you have a choice!! Just jokes, but it shows the way in which we can get too wound up over mandating reactions to terminology and not leaving it up to the poor blighter on the spot - you. I would suggest you are the aircraft captain and if you can justify the reject, ****** the ops manual!!

We adopted a second call during take off (dual or single pilot/crewman). The first call would be CDP as usual, but then the second was "committed" which meant committed to take off. This call was made when, in your judgement, you could no longer safely reject the take off and were committed to climbing out. On a runway, for example, there would be a call of "CDP" by the pilot not flying at the required height/airspeed, followed by a period in which there was a choice of rejection using runway remaining if required, followed finally by the "committed" call from the pilot flying which alerted the crew to the fact that you no longer had a choice. During helipad departures, the call committed would happen as soon as CDP was attained and the nose lowered for acceleration. The same calls could be made during the landing phase at/around LDP.

Sorry if I have confused the issue...Good luck.

[vertalop]

Suggest you consult your training department again 212 if you think rejecting after CDP is condoned. That is part of the briefing for a check ride and is only for a check ride in order to simulate a shortage of reject area. If there is safe reject area available the safest thing to do is land, not continiue and risk a further failure or fire.
To the best of my knowledge the only time that one is committed to a takeoff after forward cyclic input is on a rig type vertical takeoff where the only landing area available is directly under the aircraft.

[Attila]

As an S61 pilot, with experience on both the 212 and the AS332, I would like to raise a couple of points. First of all, with 5000 ft of runway remaining, I would reject, unless I was on a base check. Even then, if it was for real and not induced, I would still reject. As aircraft captain, the ultimate decision is yours. Secondly, the 212 section of the ops manual states, I seem to recall, that when operating over inhospitable terrain, that an automatic reject should not be carried out following an engine failure, but the captain should assess the fly-away characteristics of the aircraft. Finally, IMHO, a second call of "committed" would only serve to complicate things.

[Flat Erik]

Having flown the S-61 in various roles, I would suggest that like most things in aviation stay flexable in your approach to this.
At MTOW with no wind and high temperatures, the calculated performance will always alow you to fly away having suffered a failure of a engine at CDP. Once you have pulled to droop and accelerated and then recovered the RPM you are safe. If you then find that there is runway ahead and you have time then why not run it on? What you must not do is screw up the fly away because you are rushing to get it on the ground.
One thing at a time!
You also must tell the other bloke what you are thinking of doing and fully brief it.

Hope this helps

[Attila]

Flat Erik - I concur. Let's not lose sight of the real aim, to keep the aircraft flying.

[212man]

Vertalop,
I think you may have contradicted yourself there? In the first instance you question my point about condoning a rejected takeoff after CDP, then later on you say if there is sufficient space available the safest thing is to land. How exactly does that differ from what I said?

The reference later to not automatically rejecting comes from the Ops manual, not the FM, and refers to a failure prior to TDP where a water/swamp landing may result and given the forgiving nature of the 212 it may be possible to avoid landing (or it may not!).

[vertalop]

Sorry 212 in a rush and misread your comments.

Just to confim my view..Failure before CDP - Land. Failure after CDP and before committed -probably land. After committed - go around. Committed is at cyclic input on rig take-off. :o

[Tuckunder]

I agree with vertalop's last post. My relatively new experience in the civvy world is that, during LPC/OPC check rides, trainers tend to emphasise the "training world" ie briefing continued take offs after CDP, bomber command circuits after engine fires etc in order to complete the emergency check list drills. Completing a power check! Why?

This is fine as long as we practise relanding occasionally when there is suitable surface beneath us. Me personally, if I have an engine fire, I will land ASAP!

[heloplt]

Just an unwashed redneck bush pilot here....err...the argument as I see it is whether it should be mandatory to ignore a 5000 foot runway in front of me should something go tits up on takeoff. Now you hi-faluting Northsea Commanders all have said your piece...my turn!

If you can land back safely and in control of the aircraft, without further diminishing the current hull value of the reusable container you are driving....for crying out loud...land back! All this fancy talk about TDP/CDP...etc...bores me......you are wanting super hero pay...and that is why you are supposed to be able to make these earth shattering decisions....so put down the checklist, put aside the ops manual, ignore the managments latest policy letter....and fly the aircraft. The last place I wish to be with a sick bird is in the air.

Did the North Sea bit guys...back in the cowboy days in 58T's single pilot with the old decca....same emergencies then...less bureaucracy....same principles apply today. Know your aircraft's performance and fly to the safe side!

[Gutless]

Mr Helloplt

You are all wet, I agree with 212man and helmet fire. The more 3 or 4-letter identifiers you can come up with, the more detailed you can make the Pilots Takeoff Briefing and don’t forget the Co-Pilots Briefing, the safer the flight will be. Where do you get this “Fly the Aircraft”. Procedure is the most importance thing, follow the procedure, and nothing will go wrong.
;)

[Nick Lappos]

The problem with Cat A/Group A procedures is that the acronyms are consistant. Why don't we do what they did to N2/Np/Nf or TGT/EGT/TOT/T5/T4.5? With just a little creativity, we can really confuse the situation and ourselves.


PS That 5000 feet of runway ahead is an offer that I doubt I could turn down, and I would certainly question someone who gave up all that comforting length for an unnecessary trip around the patch. Nice to see the consensus in all the comments above!

[Roofus]

Despite what Gutless said, the pilots priority is 'Fly the Aircraft'
(I'm hoping he said it 'tongue in cheek')

Given the scenario here I'd be looking to reject the take off & get the aircraft back on 'terra ferma'

Each scenario must be assessed individually, hence we get trained & paid to make decisions. Company manuals simply cannot allow for every eventuallity, & to restrict yourself to their exact wording in the event of an emergency is unrealistic.
There is no right answer, but whichever course of action you take you must see it through to a safe conclusion.
Flying away, 'around the patch' & back in isn't the most direct route. However is does allow you to settle the aircraft into a safe flight regime, complete all relevant drills & set yourself up nicely for the subsequent single engine approach. As such it isn't an unsafe way to conduct business & could prove safer than rushing to put an aircraft back on the ground.
That said, you as the handling pilot may happily look ahead & believe that all that tarmac provides you with ample room to conduct a safe reject.
I recall the S-61 being a pleasant old girl to handle a reject in, although if memory serves she does take a fair while to stop in light winds.
The most important thing is to ensure that you Fly the Aircraft , earn your pay & bring the people in the back (& hopefully the airframe) back to earth as safely as possible! If that is acheived the actions you've taken were right. :D

[sling load]

I would find it difficult to understand how management or training pilots would want you to fly an aircraft with an engine failed AWAY from a runway in front of you. Imagine the situation where your engine failed due to a fuel contamination while youre flying downwind trying to get back to where you just left. I think management would be unimpressed in that situation. I would just get the helo back on deck if your experience tells you its possible. Whats important is avoiding an accident, and if going around does that, its the captains call.

The question is, where am I flying to after CDP with an inoperative engine? In this case, straight in front on a beautiful 5000ft runway, perfect.

For training purposes, the training captain will obviously want to see you fly away if its possible. Like the old saying goes, "if you think training is expensive, try having an accident"

Sometimes the obvious choice is the right answer.

[ 08 September 2001: Message edited by: sling load ]

[ 08 September 2001: Message edited by: sling load ]

[212man]

Gutless,
I'm not sure why you felt the need to include me in your sarcastic diatribe; nothing I had said earlier disagreed with what you or heloplt have said. I agree with Nick that the introduction of more terms to describe the same thing has confused the issue further though I firmly believ that briefs should be jusr that-brief- with only variables for a particular situation included. In training the full brief is required, to demonstrate that the pilot does in fact know it but it is not expected for each takeoff and landing.

I think it should be born in mind that this predicament can be present with much less than '5000 ft' of runway, and this is where the danger creeps in. In training you do not practice a rejected takeoff after TDP/CDP and so are not familiar with how the a/c behaves say from a 80 kt climb at 800 ft/min at 500 ft. You are familiar with how it behaves at TDP though. You may have 50 hours on the s-61 and now be flying the s-76, totally different animals in terms of reject distance. You may be the co-pilot handling and feel that you are better off rejecting, the captain might disagree-not the time for a discussion. The thread about the 76 wheels up landing highlights a potential danger (confusion over whether the a/c was to continue or reject. It was not on approach).

The list goes on with argument and counter argument. I also tend to agree that it's one of the decisions that actually we get our pay for.

[MightyGem]

To my mind, the Clear Area take off is design for a "clear area", ie the distance required for you to clear any obstacle given your a/c weight, OAT and windspeed on the day in question. For my aircraft this varies between 100 to 200m. Obviously on check rides you are required to demonstrate that you know and can carry out the correct actions for an engine failure after CDP (usually a nanosecond after in my experience).

On the airfield that I operate from I have between 500 and 1200m of "clear area", giving the opportunity to land straight ahead if required.
:p

[John Eacott]

In response to the original posting, I couldn't think of a useful or valid reason why a prudent pilot wouldn't reject, post engine failure, to a useable strip of runway straight ahead.

Apropos the other comments re vertical departures, etc. My understanding of a vertical, or helipad, departure usually dictates a fairly steep pull backwards as well as up, in order to keep the helipad ahead of the helicopter in the event of a reject back onto the deck before CDP. My experience was that this was seldom, if ever, used on offshore helidecks. The CDP on a normal departure from the hover over a NS deck is usually that close to the height AMSL, that no further vertical transition is required. The main concern was to ensure that the tail cleared the deck edge should you have to nose over to pick up Vyse following an engine failure after rotation. Fortunately the S61/Sea King never let me down, although I often wondered (worried?) about that long stretch of fuselage behind me on some departures ;)

I do recall a brief period back around 1977 when BA S61's were departing Sumburgh main runway with a (vertical) helipad type departure, much to the amusement of other operators. Never got to the reasoning behind that :confused:

Currently I have stopped operating my BK117 from helipads at 6000ft amsl with helipad procedures, as in previous years. Experience has shown that I have about 1500ft of steep valley to fly down post engine failure to build up to Vyse, rather than the stress of a vertical, backward departure followed by an OGE transition to forward flight. Apart from being reasonably uncomfortable in some wind conditions, it became really tedious explaining why we followed such procedures, especially to other pilots!! :rolleyes:

[wong]

Thank you for all the inputs. I am still puzzled as to why the Sikorsky S61 Flight Manual states that after the forward cyclic input at CDP, no attempts to reject should be carried out. This phrase was put at the notes for a ground cushion and oblique take off. It would be less confusing if they had made some qualification to that statement that if runway lenght is still available, then a reject may be still possible.

[Nick Lappos]

wong,

What you are looking for is the Universal Book of What To Do, so that no real judgement is needed, I think. We are not there.

Back when we were writing the flight manual, I was discussing the draft S-76 emergency procedures with an FAA pilot who disagreed with one (it was the standard chip light procedure - if confirming secondary indications, get to safe single engine speed, shut down the engine, etc.)

He said that this procedure would lead a fellow who was hovering at home base to take off and get to forward flight if he saw a chip light! The "discussion" was saved when an experienced FAA ops inspector said, "If he is that dumb, he deserves to die!"

If we could write down all the possibilities in a book, we would not need trained professionals, we could wire the book to the controls and save all that pilot pay (don't worry, its coming!)

I wrote the paragraph in the front of Chapter 3 of the S-76 RFM, which I do not have handy to quote here, but it basically says that these procedures are the recommended ones, but compound emergencies and conditions might lead the pilot to do other things. I wrote that so that a chief pilot wouldn't read the book to a Captain who made it home.

If a guy took the helo around in the case we are discussing, and all was OK, he did good. If he rejected and all was OK he did good. If we are confused that multiple actions are acceptable, and that this is a ambiguous world, we must adjust.

Think of the Air Florida that hit a bridge rather than violate max EPR, or the Air Canada that ordered meals while the CB's were popping prior to a toilet fire, or the AA DC-10 that was slowed to Vy while climbing at 2000 fpm and lost control. Think of the United that flew home with no controls, and made it, mostly. Procedures are guidelines, not bibical pronouncements. Lose the ability to think and you are already having an accident, it is in the future.

Any other students of Ernest Gann out there?
:)

[wong]

Nick,
Thank you for putting ito words what most of us experienced pilots are thinking and practising. You must be speaking with some authority since you have had some inputs to the S76 flight manuals. What most of us are really worried are the "people upstairs" sitting in an air conditioned room putting judgements on us should something bad really happens. If in this case, a reject after CDP has been done and there are some damages to the machine, then the book will be thrown at the poor guy who has to take all the blame and probably loses his job! That is why I feel flight manuals should be more concise.

[Nick Lappos]

Wong,
Again I find that when we seem to disagree in this forum, it is not that we disagree, it is the limitation of the medium that slows down the communication.

I fully agree that the second guessing issue is important. The seconds we are given to decide in the air palls when compared with the hours management has to consider the alternates!
;)

[heloplt]

Nick,

Very well said...absolutely spot on! The book bangers overlook words like "suggested" or "recommended" . It must be because they find little comfort in having to conduct independent thought.

They cannot grasp the concept that the book deals with issues that are considered "normal" conditions. What is sacrosanct about a red line limit when you are riding an express elevator downwards near the ground in a micro-burst such as the Delta crew at Dallas encountered?

In the simulator I have watched more than one crew placidly sit by and fly into the ground because they refused to fly beyond the "normal" limitations...and during the critique later...they actually get hostile when it was suggested they had not done all that could have been done.Invariably the defence was that I was at max power and I would have over temped or over torqued the engines!

Never mind they crashed into the ground at 90 knots and 1000's of feet per minute rate of descent.

Yes Nick....for those poseurs who asked themselves who this Gann fellow is....maybe in the future they will expose themselves to the "Truth" and be the better for it. One cannot claim to be a pilot until he knows Gann!