Light twins - single-engine climb performance

[FlyingForFun]

Hi,

Does anyone know if there are any legal requirements to achieve any particular single-engine climb performance in a light twin - preferably on-going requirements, but otherwise requirements for a new-from-the-factory aircraft?

The aircraft I'm specifically interested in is a Beech Duchess, so I imagine it would have had to have passed FAA requirements when it was new. It's now on the G register, so JAA requirements would be useful too. What I'm specifically looking for is something which I can either show to an engineer and say "this aircraft does not meet this requirement, therefore it needs fixing", or alternatively show to a pilot and say "this aircraft meets this requirement, so it's ok to fly".

Thanks!

FFF
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[FlyingForFun]

Aha - I might have just found the answer. I took a rare visit into the Flight Testing forum, and found this thread (http://www.pprune.org/forums/showthread.php?t=296256), with this link (http://rgl.faa.gov/REGULATORY_AND_GUIDANCE_LIBRARY%5CRGFAR.NSF/0/2459CA427595FBF685256687006BC958?OpenDocument). If I read it right, the answer to my question is that, because Vs0 on my Duchess is less than 61kt, there is no climb requirement. Have I got that right?

FFF
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[Pilot DAR]

Hello Flying for Fun,

All the information you're looking for can be found in FAR23.66 "Takeoff climb" and the other nearby paragraphs. If it is an earlier aircraft, CAR 3 standards might apply, but they are quite similar. FAR23 should be easily found on various websites. It is certainly on the FAA website, but not easy to find.

Do not expect to just go out and perform such a test. It requires a lot of precision to get an accurate result, and would be UN-NECESSARILY UNSAFE to test close to the ground. If the plane otherwise flys in trim, seems to handle properly, and has proper control travel available, the only other consideration for poor performance would be engine(s) not developing adequate power. Climb testing of any kind is probably the least effective way to diagnose engine power problems. Most of that kind of investigation is done on the ground by maintenance staff.

Cheers, Pilot DAR

[deice]

Can't help you on the reqs really, but I have some other input that you may want to consider.
One of Sweden's largest schools, training hundreds of pilots per year, uses the Duchess for ME training. They have specific operating procedures that keeps them far far far far away from stall conditions at any point of flight in that particular aircraft type. The Duchess is considered vicious close to stall and especially on one engine. In general single engine climb performance will be poor.

An aircraft fit to stay clear of...

[Sedbergh]

Having raised myself reading stories of Beauforts, Beaufighters, Mosquitos etc going into uncontrollable yaw/roll modes if they lost an engine on takeoff, could anyone who actually drives light twins tell me what it's like these days if you lose one engine just when you've left the ground? Is it ever practised or is it better avoided?

Just out of curiosity you understand.

[Vee One...Rotate]

If you know what Performance Category the a/c is in, you'd be able to find any climb requirements in JAR-OPS (or the FAA etc. equivalent) in the corresponding section.

V1R :ok:

[Vee One...Rotate]

Sedbergh,

I fly PA34 Seneca aircraft and we often practice engine failures after takeoff (usually at about 200' AGL) and they are, by necessity, perfectly managable. Speed control is important though - if you drop below Vmca (minimum control speed with one engine inoperative), you run the risk of not being able to maintain directional control, even using both rudder and ailerons. At altitude you could pitch down to speed up again and thereby get control back but you'd have limited options near the ground :bored:

V1R :ok:

[Sedbergh]

Ta Vee

hoped it must be something like that! I've always wondered slightly about small twins. I used to get flown out of Nairobi in a Partenavia P68 - grand until the pilot told me one day what height it would level out at, fully loaded on one.

A lot lower than Nairobi!:{

[Vee One...Rotate]

Yeah, wouldn't like to get into certain corners in a Seneca either.

In a hot climate, even moderately loaded and at moderate altitudes, when you bin an engine in the cruise you're sometimes forced to drift down as you can't maintain altitude, even with the Seneca's twin turbos :(

Of course, it was always in the name of practice and we weren't MSA-limited!

V1R

[Brooklands]

If you know what Performance Category the a/c is in, you'd be able to find any climb requirements in JAR-OPS (or the FAA etc. equivalent) in the corresponding section.

From memory (which is fallible), and its been a few years since I flew the Duchess, I think its perf E, but don't put any money on it :}

Brooklands

[englishal]

Does it have to perform at all? Most Duchesses I have flow have crap SE performance, just like most training aeroplanes (Seminole for ex).

I'd use the SE ceiling, as ceiling is defined as rate of climb of less than 100 fpm. If the SE ceiling is low, (4000' ish) as it is for many light twins then I'd assume it wouldn't climb. Some are better than others, for example the Seneca II will got o 13,000' on one engine by virtue of the turbos.

Of course if you drop below Vmc and you don't have height to loose the ONLY thing you can do is reduce power or else you are dead. Part of the FAA ME rating is to perform a Vmc demo (at height ;)) where you fail and engine, then go full power on the other and pitch up to let the speed decay to below Vmc. The thing that surprised me was the speed at which you loose it when it goes.

[rustle]

Part of the FAA ME rating is to perform a Vmc demo (at height ;)) where you fail and engine, then go full power on the other and pitch up to let the speed decay to below Vmc. The thing that surprised me was the speed at which you loose it when it goes.

Unless it is a turbocharged aircraft Vmc is a bit academic "at height" as the live one won't be developing anything like 100% power.

Did the instructor/examiner wedge something (their foot for example) under a rudder pedal to simulate loss of rudder authority at "Vmc", or did you actually allow speed to go well below Vmc and therefore close to stall speed - which engine out is fairly exciting.

[bookworm]

Does anyone know if there are any legal requirements to achieve any particular single-engine climb performance in a light twin - preferably on-going requirements,
...
What I'm specifically looking for is something which I can either show to an engineer and say "this aircraft does not meet this requirement, therefore it needs fixing", or alternatively show to a pilot and say "this aircraft meets this requirement, so it's ok to fly".


Surely the answer is "the Approved Flight Manual". I don't know what the tolerances are for SE climb, but if it doesn't do what the AFM says it does, it needs fixing.

[Fuji Abound]

Just out of curiosity you understand.

You will do them on your initial MEP.

You will probably do them on your renewal.

Depending on the twin the performance varies significantly as does handling for all the usual reasons concerned with where the engine is mounted and which one it is, or whether it has rather nice counter rotating props.

I dont think things have really change with "modern" twins - not that there are very many. The DA42 at MTOW has little performance reserve and because rather like most modern aircraft the airframe is "slippery" to extract the most from low powered engines managing the aircraft on one engine is critical. At MTOW in my opinion you need to be right on the ball should the worst happen at the most critical time and it could easily catch out a rustle or low time pilot.

[englishal]

Unless it is a turbocharged aircraft Vmc is a bit academic "at height" as the live one won't be developing anything like 100% power.

Did the instructor/examiner wedge something (their foot for example) under a rudder pedal to simulate loss of rudder authority at "Vmc", or did you actually allow speed to go well below Vmc and therefore close to stall speed - which engine out is fairly exciting.
Yep true. Isn't it called Coffin Corner where Vmc and stall coincide?

It was a Seneca II and so was TC'd (actually develops more HP at altitude than sea level). The examiner didn't wedge his feet under the rudder pedal then, though I believe now they are advised to do so nowadays. I think I would if I were an examiner ;) I chatted to one FI who lost 5000' in a Vmc demo gone wrong....:eek:

Regarding the DA42 - we failed one engine at 5000' in California last year. The weather was reasonably warm, we had lots of fuel (long range tanks) and 3 blokes with overnight baggage onboard. The thing perfomed amazingly and we had no problem climbing at all....(being TC'd helps of course).

[rustle]

At MTOW in my opinion you need to be right on the ball should the worst happen at the most critical time and it could easily catch out a rustle or low time pilot.

WTF is that supposed to mean? :hmm:

[DFC]

You are only legally required to have single engine climb performance when operating commercially and in a situation where you can not see and avoid obstacles.

Since you are probably providing training for the CPL then the requirments of JAR-Ops for perfromance class B are appropriate for understanding the situation.

In terms of "is this aircraft performing correctly" then the reference is the flight manual which will schedule the gross performance that the aircraft should manage.

Apply your factors to get net performace and confirm that the aircraft is meeting those requirements with ease.

I would not use the certification standards to confirm performace of an established aircraft as the aircraft may have be designed to exceed those minimum performance standards and while grossly underperforming may still meet the minimum requirement.

The flight manual is your legal guide. The Manufacturer will also help.

The friendly pilots at the CAA flight test department will also help you with a better and more specific answer.

Regards,

DFC

[Nathan Parker]

Yep true. Isn't it called Coffin Corner where Vmc and stall coincide?

Not traditionally, no. The Coffin Corner is something else entirely.

[High Wing Drifter]

Nathan is correct. Coffin corner is a situation when you cannot go slower nor faster without stalling or exceeding speed limits. Typically a problem with swept wing jets that climb high enough that stall and Mmo coincide.

With regard to Vmc and stall, it isn't a corner because you only need to increase speed to get out of it.

[dublinpilot]

At MTOW in my opinion you need to be right on the ball should the worst happen at the most critical time and it could easily catch out a rustle or low time pilot.

WTF is that supposed to mean?


I'm pretty sure it's supposed to be a compliment, saying that you are a high time pilot and not normally easily caught out. ie. you're the contast to the low time pilot.

People find insults anywhere they can :rolleyes: Are you sure you're not an ex g/f of mine? :p

[Bravo73]

WTF is that supposed to mean? :hmm:

Could it just be a spoonerism of sorts?

How about:

"At MTOW in my opinion you need to be right on the ball should the worst happen at the most critical time and it could easily catch out a rusty or low time pilot."

:8

[FlyingForFun]

Thanks for the references and thoughts, everyone. Pilot DAR - you are, of course, correct about investigation being done on the ground by maintenance staff - but they swear nothing is wrong, and I'm not convinced, which is why I'm asking the question.

The POH certainly contains performance graphs, but I don't think (and I'll have to double-check this) they are any different between de-iced and non de-iced aircraft. The maintenance organisation tell me that they would expect a de-iced aircraft to not perform as well as the manual says because of the de-icing strips on the leading edges. That's why I was looking for something else... but it seems that this something else is not there, or if it is it's impractical for me to use anyway.

Sedbergh,could anyone who actually drives light twins tell me what it's like these days if you lose one engine just when you've left the ground? Is it ever practised or is it better avoided?My company doesn't allow simulating engine failures below 200'. At 200', it's no problem at all as long as you do everything correctly. If you don't do it correctly, all bets are off. (Only very recently, a student of mine went for the wrong rudder pedal when I failed an engine at 500'. It didn't take very long at all before the student lost control completely, and asked me to take over. I did - but only because a crash was imminent if I hadn't - closed both throttles, levelled the wings, back under control again. But of course that's not an option closer to the ground.)

As for being below 200', this ought to be taught in a sim, and those of my students who go on to do the IR with me all experience it. I don't usually pre-warn them I'm going to do it, although they all know the company standard pre-takeoff brief which says that if a problem occurs on the ground, or in the air with the gear still down and runway still ahead, close both throttles and land back on the runway. The majority of students, despite having just briefed themselves on what to do, try to take the failed engine into the air without enough speed to maintain control. Every single one of them crashes, and every single one of them never makes that mistake again.

FFF
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PS - Rustle, I don't know if it's just me, but I took Fuji's comment to be a typo, intended to be "it could easily catch out a rusty or low time pilot"? Edit, because Bravo beat me to it!

[rustle]

Well I'm pleased for you that you three see the "error" in that light (compliment or typo), but having had > 24 hours and multiple visits* to the site to fix it it remains unaltered.

* Everyone is visible when they're here and I have visited a few times today when FA has been around; anyone posting to a thread would normally return to it to see any follow ups.

Sorry, the question remains: WTF you on about FA?

[average bloke]

FFF,
You need to look at assumed engine failure height. IE, for an MEP, the engine is assumed not to fail below (300' I think, although it's been a while). As the engine is assumed not to fail below this height, if it does you are guaranteed jack sh*t. This will be in your ops manual among other places. After this height, you must be able to construct a +tive climb with obstacle clearance to 1500'. This info is in the POH, and is up to the pilot to determine for any given conditions.

Good job punters don't know this when they get in the likes of a chieftain!

[Sedbergh]

Gulp:uhoh: - it all sounds like a recommendation for big singles! It worked for Mr Lindbergh:)
Ok, scenario - Boeing 777 full of Sedbergh and his overweight hand baggage, mainwheels just left the deck, one engine sheds the turbine blades - does el Capitano have shut the other down & land straight ahead???? M25 here we come?

I know, wrong thread & accusations of scaremongering but just out of interest!

[Bravo73]

Ok, scenario - Boeing 777 full of Sedbergh and his overweight hand baggage, mainwheels just left the deck, one engine sheds the turbine blades - does el Capitano have shut the other down & land straight ahead???? M25 here we come?


If he's already in the air then he's already past V1. So he continues, sheds a bit of fuel and then lands (either where he came from or, if needed, diverts elsewhere.)

(Or, at least, that's my very basic understanding of the situation. Although I'm sure that Kit will be along in a bit to patronise me then set me straight...:rolleyes:)

[Sedbergh]

Brav

But just because you're past V1 it sounds from other posts if you're not necessarily past Vmc?? - at least in some a/c.

I'm sure Mr Boeing has it all worked out:ok:

[Bravo73]

V1 is the decision point. If a power unit goes before this point, you stop. If a power unit goes after this point, you continue.

Unless of course, the B777 was sat at the end of, say, a 20,000ft runway. Then the captain might decide that he's got enough room to stop in. (But then you don't get many of those!) ;)


Here's what Wiki has got to say about V1:

V1 critical engine failure recognition speed. V1 is the minimum speed in the takeoff, following a failure of the critical engine at VEF, at which the pilot can continue the takeoff with only the remaining engines. Any problems after V1 are treated as inflight emergencies. In the case of a balanced field takeoff (http://en.wikipedia.org/wiki/Balanced_field_takeoff), V1 is the maximum speed in the takeoff at which the pilot must take the first action (e.g., apply brakes, reduce thrust, deploy speed brakes) to stop the aircraft within the accelerate-stop distance and the minimum speed at which the takeoff can be continued and achieve the required height above the takeoff surface within the takeoff distance. In this context, V1 is the takeoff decision speed.

[bookworm]

But just because you're past V1 it sounds from other posts if you're not necessarily past Vmc?? - at least in some a/c.

I'm sure Mr Boeing has it all worked out

Mr Boeing makes exclusively Performance Class A aeroplanes. Mr Beech does not.

[Finals19]

Did some IR training in a BE76 in Canada, and single engine in the missed with 2 onboard and near full fuel provided fairly good climb performance at sea level, even in above ISA conditions. Also did some IR training in the Seneca 1 and that thing was a pig. We only practiced engine failure in the overshoot simulated at altitude, and until you got the a/c cleaned up it was pretty much at zero climb even with the good engine firewalled. That assumed you got on the pedals quick and rolled five degrees into the live engine.

JAR OPS states perf B for MEP light twins. So, requirement to clear obstacles by 50 feet (I think) to 1500' after take off and a 1000'/5nm positive gradient en route clearance requirement as well as being able to hold altitude at or above MSA.

Used to fly Piper Chieftains for Air Taxi. That thing had a VG kit on it that upped our MTOW to 7348Ibs from 7000Ibs, however I would put money on the fact that if we'd lost an engine below 400' or safe obstacle clearance height, we might have just held altitude up to about 7000 on a good day. The SE service ceiling was supposed to be 13800...my point being that performance figures in the POH are based on a shiny new test aircraft!

[Nathan Parker]

But just because you're past V1 it sounds from other posts if you're not necessarily past Vmc?? - at least in some a/c.

Not for airplanes certified by the FAA. V1 must be equal or greater than Vr, and Vr must be greater than Vmc.

[average bloke]

Gulp - it all sounds like a recommendation for big singles! It worked for Mr Lindbergh
Ok, scenario - Boeing 777 full of Sedbergh and his overweight hand baggage, mainwheels just left the deck, one engine sheds the turbine blades - does el Capitano have shut the other down & land straight ahead???? M25 here we come?

The thread is about light twins, so lets not get confused and get a load of replies about V1 etc. This does not apply to MEP type aircraft (perf B).
JAR OPS states perf B for MEP light twins. So, requirement to clear obstacles by 50 feet (I think) to 1500' after take off and a 1000'/5nm positive gradient en route clearance requirement as well as being able to hold altitude at or above MSA.

Nearly correct, except that it is after assumed engine failure height, ie 300'. My previous comment stands, that below this you are guaranteed jack.

All the comments about my twin performed ok on this or that occasion are not of any value in answering the question. FFF wants the air law side of things. He flies light twins, so knows how they perform. I have to say though that I am surprised by the amount of people who do appear to fly them without knowing the facts!

[englishal]

Ref a post near the beginning....

IF the POH states a "SE Ceiling of 3000' "then you must be able to climb at >100 fpm at MAUW to SE ceiling. If you can't then the plane is not performing (after taking into account density alt of course).

as well as being able to hold altitude at or above MSA.
What happens when MSA is 10,000'? No way will a BE76 at MAUW climb.....

[FlyingForFun]

All the comments about my twin performed ok on this or that occasion are not of any value in answering the question. FFF wants the air law side of thingsVery true, AB! I do find the thread creep interesting, though, I have to admit - so long as it doesn't detract from the answers to the original question.I have to say though that I am surprised by the amount of people who do appear to fly them without knowing the facts!I think a lot of the posts on this thread are from people who don't fly twins, which is why there is a lot of confusion, and a lot of discussion of V1 (which does not apply to light twins, as others have said). In fact, there is so much wrong information on this thread I'm tempted to ask the mods to delete it in case anyone starts quoting things from it! Normally I'd try to correct the errors, but there are too many here to know where to start!

Anyway, thanks for all the input. As it happens, I had a chance to fly the aircraft in question with one engine feathered just the other day, and I have made a note of all the relevant numbers to compare to the POH when I get a chance. I will also repeat the exercise with another aircraft in the fleet and compare both the performance and the POH for the two aircraft. Hopefully that will give me enough data to decide whether I need to push the issue any further with my maintenance organisation.

FFF
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[Mimpe]

The anwer to your questions regarding the legal requirement is covered above - there is a legal climb requirement at MTOW but as you know the realities of situation are pretty sobering.

Practicing engine out after take off at 200' has led to deaths in Australia, and is not done.
I did my Duchess rating 2 years ago, and loaded nowhere near MTOW on a slightly warm day ( perhaps 28 deg C) at 2,300 feet I could only achieve straight and level and perhaps the most subtle of climbs ie 20 fpm.
Its generally taught that if you cannot achieve immediate control with straight and level flight at low altitude on EFATO then the glide ahead shutting down the active engine is your safest bet by far. At least the crash will have some control.

(Having never been in this situation but..) if the gear/flaps are up and with rudder authority and max/RPM in the operative engine and dead wing up/nose level, you will know immediately ( within 2-3 seconds) if you've got a workable aircraft or not.

[Pace]

The best advise I heard with light twins is that the second engine gives you more options. With more options come more choices! With more choices the option to make the wrong choice.
Part of the bad safety record of light twins IMO is the training which instead of looking at all the options with the second engine concentrate on a climb and blue line.
That maybe the correct choice in some situations but not all. Fixating on blue line climbs is the reason many get into a mess.
Most twins do badly climbing on one engine especially hot and heavy but I perfectly happy in level flight.
I can remmeber many moons ago doing a totally stupid thing of shutting down a Seneca Engine in the cruise crossing the English channel on one, starting it up and landing in France.
Ok we were at 3000 feet but the aircraft does not know that it could equally be 300-400 feet.
Loose an engine at 400 feet ? Why climb? why not stabilize things in level cruise and then edge up fraction by fraction using the trim wheel.
Most airfields you can fly low level circuits.
If they are in mountainous regions chances are you will not climb out on one anyway.
Above all if its all going pear shaped keep the thing flying push the nose over and take to a field like a single.

Pace

[AdamFrisch]

Agreed with Pace. Almost all sticky situations in single engine operations can be gotten out of immediately by reducing good engine, but this is rarely taught. Fixation on blue line is the norm.

But basically in take off scenario airplanes fall into two categories: those who's Vmca is close to stall speed and those who's Vmca is above stall speed.

In the former type, an engine failure at rotation is manageable in practice. Just lower the nose, clean it up swiftly and continue. My Commander falls into this type with a 67kts Vmca which is close to its stall speed depending on flap setting. I regularly roll her up to close to blue line before I rotate anyway, just to have a little more margin.

In the latter type, you're looking at a stickier situation unless you can very quickly transfer to a higher forward speed (ie get nose over) to get rudder authority. Unless you have enough altitude to be able to reduce good engine, which is not normally the case at takeoff, of course. There is another remedy; Don't rotate at V1, continue up above blue line before you rotate if you have rwy to do so. Might wear a bit more on your gear and tires, but could get you into a safer zone. The Aerostar falls into this later category. It has a 'dead mans zone' between V1 and blue line (can't remember exactly the number now as I don't have POH yet) where you wouldn't want the engine to fail. Blue and red line are also pretty close.

All I can say about the 520 is that she'll climb about 3-500fpm if one engine is caged and feathered at low altitudes. Once you trim out the yaw, she can fly all day like this. Climb with it uncaged, its about 1-300fpm. With it unfeathered and with gear out it's pretty much nil. There is no requirement of twins that have a stall speed below 61kts to demonstrate any climb performance at all in the FAR's.

Maybe a soft field technique would be beneficial to use for the higher Vmca types? You'd rotate as normal, but then keep aircraft in ground effect until blue line in case something would happen, but once you've reached that speed you pull back and climb away?

[mad_jock]

The Vmca is one of the worst understood issues of twin single engine flight.

Current doing battle with a particulay thick polish TRE who would imagine I imagine is quite an expert on Sep agr aircraft. Twin TP he is a bloody liability seems to think V2 makes you safe what ever you are doing.

[Big Pistons Forever]

In the former type, an engine failure at rotation is manageable in practice. Just lower the nose, clean it up swiftly and continue.



I have to say I completely disagree with this statement. The problem is that all light twins will only make their meager 200 to at best 300 feet per min climb if they are at the blue line speed, with the failed engine feathered and the gear and flap up. At or right after rotation none of that will happened and it is unlikely that the aircraft can maintain level flight while all the clean up happens. Even if you can accelerating from lift off speed to blue line and thus positive climb performance will be extremely problematical as there is virtually no excess power when on one engine. My experience is that being even 5 knots below blue line will wipe out any climb performance.

IMO for any piston twin any engine failure before the aircraft is at blue line with gear and flaps up and a strong positive rate of climb means the only safe course of action is to close both throttles and land straight ahead.

Personally I follow the SIMCOM method. Your hands stay on the throttle until gear/flaps up, blue line and positive rate. After that you shift your hand to the prop levers and hold them their until the 500 foot climb power selection.
If the engine fails when your hands are on the throttles you pull them both back. If the engine fails with your hands on the prop levers you cancel teh yaw with rudder lower the nose to a 5 degrees nose up attitude, identify with dead foot, verify by pulling the appropriate prop lever to just above the feather gate and then feather. You have only one action to carry out and the aircraft will be in the best possible condition to continue.

However you still must verify a positive rate of climb. Failure of the aircraft to climb means you immediately pull both throttles back and take your lumps straight ahead.

BTW for the Aerostar I rotate at 100 kts, gear up at positive rate, flaps up through 105 kts (Vxse) and hands go from the throttles to the props through 115 kts (Vyse).

[AdamFrisch]

I'm sure you're right BPF. It has never happened to me, that's why I said in practice but should probably have said in theory. Anyway, I tend to rotate closer to blue line anyway to give myself some margin, even though she wants to fly 20kts below that.

On the Aerostar that's probably not as feasible as the Vyse is much higher, so there one will have to live with a short "dead man's" gap, at least in the interest of saving your tires and on shorter airfields. But who knows - time will tell.

[Pace]

I am going to repeat this as I consider it vitally important to flying LIGHT TWINS!
The other engine gives you more options! With more options come more choices! With more choices the option to make the wrong choice!

Light twins have a bad accident record and frankly I blame the training which is more directed at the pilot moving on to flying aircraft which will climb at 1000 fpm on one.
The majority of the twin rating revolves around shutting down an engine and going for a blue line climb :ugh:
What happens to the poor pilot desperately flying blue line with minimal climb when the aircraft hits sinking air and everything goes down hill fast?
He sees a descent pulls back and blue line speed is fast gone or the pilot who shuts down an engine still producing 30% power because he is so channel trained that he goes into the blue line mode on automatics?

Light twin training should involve lateral thinking and decision making exploring all the options open to him.
Every engine failure will be different! in different conditions, different weights, different temperatures, different types of failures and the pilot should be trained to being able to identify the best solution even if that means shutting both down and heading to a field.

What does a light twin do best on one engine? It certainly is not climbing! It cruises well on one engine so why not look at setting up a cruise! Take a Seneca Blue line is around 89 kts from memory. Let the aircraft take up level flight it will accelerate to 120 kts, trim it! now trim back and let it step climb till the speed decays to 100 kts. set up level cruise again accelerate to 120 and trim back to 100 kts again. Try it and add this option to flying blue line or closing both .

Only then will we get an improvement in the bad accident stats with twins

Pace

[Jetblu]

Agree Pace, but their are light twins and light twins.

The Seneca, Seminole, Duchess, Couger and Partenavia that I flew, I would not want to lose an engine at or near MTOW. They were pigs for climbing at blue line and your suggestion/s would have been a go'er.

The C310, C421, BE58 and KA200 are a doddle and will happily climb away at blue line.

All horses for courses.

[Pace]

F900X

Totally agree there is no way an aircraft will climb to its service ceiling for single engine.
Thats it cruise service ceiling and that backs up my argument of why attempt to climb?
Why put the aircraft into having a higher AOA and resulting drag trying to haul a deadweight airframe skywards with one engine.
Unless of course your light and temps are cold.
If a pilot is disciplined enough to peg blue line he is not gurananteed a climb! he is not even guaranteed level flight and maybe even have to fly blue line with a negative reading on the VSI and altimeter.
That is the problem because the training drums it into pilots to climb and when they do not they pull back! Dropping airspeed, more AOA, more drag, more rudder its all going pair shaped fast.

I had an engine failure at 200 feet in a Seneca 4 WITH 100 HRS TT and at grosse.
3 sheared rocker shafts caused by overtorque at manufacture.
The engine was probably still producing 30% power although vibrating badly!
I knew instinctively that if I followed my training by feathering and shutting down the unit i was going to go one way and that was down.
So I kept it going with one hand poised on the prop lever incase there was a bang and coaxed it up to 800 feet where the vibrations got so bad that once level I shut it down, came round and landed.
So I am a firm believer that you have a number of potential ways out! blue line and climb is one but not always the right choice and there are other options which are not taught in the multi engine rating syllabus.

Pace

[Big Pistons Forever]

The C310, C421, BE58 and KA200 are a doddle and will happily climb away at blue line.
.

I can't say I agree at all that any of the above will climb "happily" away. The C 421 has a published single engine rate of climb of 305 feet/min. That means if you lose the engine right after takeoff you are going to need at least 7 miles to climb to a thousand feet AGL circuit altitude, and that is the best case scenario.

A low altitude engine failure in any piston twin is a desperate emergency.

[Pace]

F900X

200 feet!!! Yes a bit low for a level circuit! Do you have a full failure? Do you keep the damaged engine going? Do you feather and shut down? Blue line at 200 feet are you getting a solid climb? If not look for a reasonable field and use the engine to control your glide into said field.
What are obstructions ahead like? Can you steer a course away from the obstructions? Will you outclimb them on one anyway? 200 feet you have to make a quick decision as you would at 50 feet!
Air below the plane and you have potential energy from the airframe to tap into! room to reduce AOA.
but this is the point you have a number of option not just doggedly going for a blue line come hell or high water as the training seems to concentrate on.

Pace

[Pace]

F900EX

I Know your not getting at anyone :ok: Most twin training has revolved around would be commercial pilots getting multi irs.
They transition to much more capable aircraft where an engine failure is no big deal.
Light twins are a rule to themselves and should have specific training to fly them and respect their limitations

Pace

[Jetblu]

BPF.

My statement was probably a bit tongue in cheek and I will rephrase for clarity.

From that bunch, I would happily continue to climb away at blue line knowing that I will achieve a reasonable positive ROC.

It is true, all engine failures are emergencies and it is something I drill myself on for keeping current and ahead of the game.

You have selected the C421. This is not the best aircraft for practice EFAT
due shock loading G520's/reduction gearbox wear etc etc, but I still put myself through the paces with this ship nevertheless.
Full tanks, 4 POB, OAT 10c with simulated EFAT at 300ft, I was achieving 350ft - 450ft min ROC.

[youngskywalker]

I would imagine the 'shock factor' of a real engine power loss would be the biggest problem, those few seconds of disbelief and denial would soon eat up any chance of successfully climbing at blue line after take off. Crashing straight ahead with the wings level is what I try and brief myself on.

By the way, the KA200 isn't a piston twin and cannot really be compared in the same category as the others, but I'm sure you knew this. It's possibly the easiest of the lot with rudder boost, auto-feather and an excess of power.

[Jetblu]

YSW

Believe it or not, at every take off, I am always prepared and waiting for a donkey to quit, so I can confidently ascertain a blue line climb out.

I thought that we were talking about light twins ?? Now you tell me. ;)
I guess the biggest clue for me was putting Jet A1 in it. :p
Even with autofeather, they are far from a walk in the park with EFAT.

[Big Pistons Forever]

One of the challenges of twin training is accurately setting zero thrust. My feeling is most of the time more than zero thrust is being set and thus an unrealistic level of performance is achieved.

I did some training for a Navajo operator a while ago. The Chief pilot was sure that he could fly away from a low altitude engine failure and that the airplane climbed "just fine" on one engine. To disabuse him of his opinion we loaded the aircraft to gross weight climbed to 4000 feet AGL and actually shut down and feathered the engine. It was a big eye opener to everyone at just how little climb performance there actually was and as a result the SOP's were changed to require closing the throttles if the aircraft was not already clean and at blue line and even then be aware that the aircraft may still not have adequate performance and a glide landing straight ahead may be the best response to the engine failure.

The other problem with twin training is the engine failure exercise is always taught as a binary problem with only two conditions engine runs perfectly - engine has totally failed. In the real world a partial failure or surging engine is a more likely failure mode and is virtually never addressed in training.

[youngskywalker]

I didn't say it was "a walk in the park", but I'd rather have an EFATO in a King Air over any other piston twin any day.

[Big Pistons Forever]

A King Air 200 with autofeather is in a whole different league than any piston twin. With that aircraft you have enough real performance that climbing away from a EFATO now becomes a realistic option.

[Ejector]

Not all light twins will climb out on one.

This light twin wont. Hence it is subject to single engine rules for many things.

But it could happily take a good chop. :)

http://www.fiddlersgreen.net/aircraft/Grumman-Goose/IMAGES/Grumman-Goose-parked.jpg

[Ejector]

A King Air 200 with autofeather is in a whole different league than any piston twin. With that aircraft you have enough real performance that climbing away from a EFATO now becomes a realistic option.

I Agree 100%

I also agree with this post above (http://www.pprune.org/private-flying/296437-light-twins-single-engine-climb-performance-3.html#post7874051) from Big Pistons Forever. Such a true statement.

[Pace]

The other problem with twin training is the engine failure exercise is always taught as a binary problem with only two conditions engine runs perfectly - engine has totally failed. In the real world a partial failure or surging engine is a more likely failure mode and is virtually never addressed in training

I agree with BPFs satement too. Light twins have always had a bad record in the event of engine failure.
In my own engine failure at 200 and grosse, 3 rocker shafts complety sheared on a Seneca leaving me with approx 30% power and a very badly vibrating engine.
Training would have meant me feathering and shuitting down the unit and without doubt I would have gone down.
Keeping that unit running for as long as possible gave me a slight climb.
i would recommend pilots experiment more with the options.
Who ever practices PFLs in light twins to get used to the descent profile yet that is an option.
Who practices going from climb to cruise as at 400 feet that is an option.
Who practises when to chuck away trying to fly blue line.
Who actually shuts a unit down!
In the Citation I fly we have flown single engine circuits and even flown a touch and go on one.
Totally different kettle of fish to a light twin.

pace

[Pace]

Second from last line in your post above, I wouldn't advertise that as it is a very big no no.

Unless of course you mean landing on one engine then take-off on two after a/c is reconfigured

Of course I meant that : ---)