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Cessna 340 - lookin' for advice...

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Cessna 340 - lookin' for advice...

Old 3rd May 2008, 11:58
  #1 (permalink)  
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Cessna 340 - lookin' for advice...

I've posted this on D&G, my usual hangout, but throught I might trawl here too, just in case...

OK, so I done gone and done it again. Bought another toy. (Reckon I'll get my internet disconnected after this A very nice Cessna 340 is being added to the fleet, initially in the US, and then back to NZ. Yes,it checks out very well mechanically, and yes, it's very well priced, given the twin market. I know there's a lot of wisdom here, so thought I'd ask if anyone knows much about these questions:

1. Short field ops. I know, I know - it's not possible, per se, and it's sure not a short field machine. Still. Anyone know what the shortest possible/reasonable/safe takeoff would be for a 340 operating at very low weights? Say, 2 people and 40 gallons/250 pounds fuel. Published take off is 1600 feet or so, but that's at full gross, without VGs, and (I think) involves waiting till the machine is at 90 knots or so before rotating. Anyone with real world experience able to answer this one? A related query is:

2. If you take off at the slowest possible speed, in a fairly powerful twin, is it true that a catastrophic engine failure means you could get into a VMC roll even if you had perfect reactions, in terms of pulling both throttles and applying full opposite rudder? A very experienced instructor and friend of mine says this is the case. He has a lot more experience than me, but still, I'm surprised. I'm willing to "pull the other one" and accept whatever I get if I have a low speed engine failure on take off, but was surprised to hear that no matter what, I'll be heading into the trees upside down. What do you guys think? Is my instructor friend correct?

3. Training. Amongst other machines, my current twin is an old Aztec. The 340 is, of course, a big step up. I can and probably will train in the US. Is Flight Safety (Kansas/Long Beach) overkill? What's a sensible expectation re syllabus and training time for the transition? I'm not looking for shortcuts here...but I'm only VFR, and I wonder if FS's training is skewed too much to IFR?

4. Getting her down to NZ. Am thinking, to be conservative, that the wisest thing to do is take the wings off and pack her into a 40 foot container. Anyone know a. how much of a big deal it is to de-wing & pack such a big aircraft (is it even possible??) and b. contacts for 40 foot containers & shipping from US to NZ?? Of course, a good contact for shipping US to Oz would be fine, cos I'm sure they can get a big box to our little country too...

Any help and all thoughts would be welcome. If anything I've said sounds dumb, well, I guess I'll find out soon enough - but would appreciate the thoughts of them what know...
lostpianoplayer is offline  
Old 3rd May 2008, 12:45
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In a twin rotation speed should not be below Vmc, therefore:

1. A short field take off in a twin is limited by the acceleration to Vmc ( plus safety margin, usually +5kts or even +10kts)
In a single the shortest possible take-off is actually a combination between the soft field T/O technique and the short field T/O technique.
You can't (shouldn't) do this in a twin. It will lead to lift-off below Vmc.
So the ground roll in a twin is affected by:
-density altitude (if non turbo)
-runway surface ( dirt, gravel, grass or concrete)
-runway slope.

2. YES.
The definition of Vmc under FAR 23 :

".........critical engine suddenly inoperative with the working engine at maximum rated T/O power in T/O configuration (=gear up)"

Flight controls really work based on a very simple principle:
airflow x deflection= effect
Since airflow is speed it means speed x deflection= effect.
Vmc is an aerodynamic control speed.
So at a speed below Vmc you have no (or insufficient) aerodynamic means to maintain control. So you will end up in the trees upside down.
It doesn't even have to be that dramatic, at very low altitude like 20'-30' you don't need a whole lot of bank to get the wingtip to strike and the aircraft will cartwheel. It doesn't need to roll upside down to end up in a heap.

3. I'm sure Flight Safety has a VFR only course, or if not they should be able to adapt the course they have. Simply swap the IFR training flights for extra VFR.

4. Be tempting to fly it with a very experienced ferry pilot.
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Old 4th May 2008, 05:36
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Your answer, B2N2

Thanks for this. I think you're right, about ferrying v crating, and will do it that way. One fella on D&G pointed out the same thing - AND volunteered to help with the ferrying!

Re VMC, I want to be clear about the fact that this is NOT an argument - I just want to learn, so please do consider my question in that context. (I've seen too many Q's on PPRuNe deteriorate into e-yelling matches, and that's not where I'm coming from - I'm in no way an expert on twin ops, and don't know enough to authoritatively start an argument anyway So, my further Q is:

Yes, I understand the definition of VMC. I also understand why trying to continue to fly below VMC is likely to result in some version of the scenarios you've outlined. What I don't understand is why, if you were hair-triggered to cut power on the live engine, as close as humanly possible, as well as applying immediate opposite rudder (aileron?), then wouldn't the removal of the live power remove the roll/yaw immediately, and thus turn it into a common-or-garden engine failure situation? (I know, more speed and intertia than a single, so less survivable, but still much more survivable than going in w/o wings level...) ?

Also, a minor addition - I understand the effect of the after market VG kit, which is fitted to this aircraft, is to reduce VMC to very close to VS. Does that make a difference?

Your thoughts welcomed.
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Old 4th May 2008, 08:49
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First of all you will find you can not fit a C340 in a container without cutting it up. Main problem is the engine mounts to end of Nacelle is over 8 feet 6 inches so it will not fit in a tall container. Over sized shipping is very costly and would be deck cargo getting into all kinds of corrosion issues. So a ferry flight is in your future.

Get Vortex Generators....they lower the VMC by 11 knots on a C340 to 71 knots....plus you get a 300lb gross weight increase.

Short feild takeoffs at low weights are not an issue. We frequently depart from 1600 foot feilds and rotate in about 800 to 900 feet. Yank it off at 80 knots and then put the nose right down to build speed to 100+. Of course if an engine does fail at or right after rotation be prepared to close both throttles quickly if it starts to roll. VMC demos with gear down and 15% flaps show resonable control until 70 knots. But I do believe it would not be the same under a take off situation.

Now landing in 1600 feet can be an issue. If we are not under 85 knots and are not going to touch down in the first 100 feet we go around. If you are under 85 knots and touch down early you can stop in 1400 feet provided your technique is good and you plant it on with no float. We use a slightly high sink rate, 600-700 ft and try to hit in a three point and push the nose over on touch down. Then max braking when able. Hard not to lock up the brakes until under 40 knots.

Great airplanes, shame what is happening to their values.....
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Old 4th May 2008, 09:24
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The 340 - container from US - NZ still req'd. Anyone know?

Slatch, thanks for this. Yep, I've come to the same conclusion re ferry flights. I'll fly it around the US for a long time first, to be sure of the machine, and spend a year planning it, find a highly experienced person to take with me, then I guess it's the Big Blue for me

Thank you very much for the real world info - I appreciate it. I do, in fact, have VGs fitted, so I guess VMC is below VSO. Hopefully my machine will have similar performance to yours. Is yours the 310 hp model?

And whereabouts in CA are you? I'll be over there late this month/early Ma to pick up the 340 in Fresno, and will be flying all round the place, particularly anywhere b/w LA & the Bay Area. You obviously know a bit about real world 340 ops. As a new 340 pilot, I'd love to buy you lunch and pick your brains, if you'd be avail. No offence taken if not - maybe PM me either way?

B2N2, I'm still interested in your response, if you feel like it.

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Old 4th May 2008, 13:20
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Lostpianoplayer, fantastic screen name by the way.
I know too little about 340's to get involved in the short field discussion.
Engine out scenarios at some point always end up in a very gray area.

A twin is only truly different from a single if you respect it's virtues and vices.
The second engine is only able to do you any good if you stay in a fairly abstract performance envelope.
I am currently in a job where we rotate at Vmc +5, climb at Vyse+5 and we do not allow operations from runways less then ASDR.

Having said that, here is the flip side of the coin. Probably some arguments that you are familiar with.
The engines don't know if you are flying over water. The engines don't know that you are flying at night. The engines don't know that you are attempting a very short field T/O.
Outside the above mentioned envelope you are essentially flying a single since the second engine will not do you any good. But then, most of us have several thousand hours flying in a single. We do not hesitate to fly at night, over water or take-off from a very short field.
So is it unwise to explore the envelope of a twin and operate outside of it?
Not necessarily. There are certain area's of the world where this is done on a daily basis. Alaska, Afrika, remote regions of SE Asia.
Here's a great example:
You just need to be very aware that if things go pear shaped, the chances of walking away diminish compared to a single.
No only weight and inertia is an issue, a medium sized twin can carry heaps of fuel and what I really dislike about light and medium twins is the awkward entry and exit for the pilot. No door on the pilot's side or you have to work your way through the cabin to get to a door. I have absolutely no statistics to back this up but gut-feeling would tell me that survival rates would go up if some more convenient exits were provided. some of the "bad" examples:

P68 Partenavia, look at the location of the door;

Rockwell Aero Commander, pretty much same door location:

One of the better ones, Twin Otter:

Last edited by B2N2; 4th May 2008 at 13:33.
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Old 7th May 2008, 11:24
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Lets think about this

The Cessna 340 is a great plane. With RamVIís and VGís the published rotation speed is 91 kts with a climb out of 108 kts to safe altitude. To consider speeds below these is crazy. If an engine pukes on takeoff, forget the catlike reflexes and honed skills, get real. If you donít value your life maybe you wife, child or passenger does. That 335 horse engine hanging on the right side is producing significant torque and is purpose built to roll you over if you are not prepared. It takes time, maybe four or five seconds to stop the fuel flow and actually stop producing power, not to mention the inertia that 2700 rpm of all that machinery spinning takes to slow down. It takes probably 2 rpm, or .000741 seconds with a busted crank to stop the inop engine. That 335 horsepower on the right wing can lift one hell of a lot of metal in 5 seconds without proper counter forces in an asymmetric engine out scenario.

Regarding runway length, I will not fly mine into anything less that 4,000 ft. Landing in 2,500 ft is no problem; however the engine out on takeoff scenario requires a few more considerations. To accelerate to rotation speed, liftoff, have an engine fail and land safely requires at least 2,700 feet for Sky King to do. So why push it, include a safety margin.

If the mission profile does not fit the 340, look at the Maule or the Caravan or other purpose designed short field aircraft. Donít buy the 340 because you can get a great deal on one and make believe its got STOL capabilities.
Lifeisgood is offline  
Old 7th May 2008, 12:49
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B2N2, long time no see.

You can take the Twotter out of your list, there is a pilot side hatch (on all versions as far as I can remember). Take a quick peak at your last photo, you'll see the hinges just visible.
But from your post I'll take it you like the Aerostar concept, entry and exit are pilot side ONLY; I would hate to be stuck all the way on that back seat.
Gotta love planes build by pilots for pilots!
Take a look: Ted Smith-Aerostar 600
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Old 7th May 2008, 22:33
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I have about 350 hours flying a VG equiped C340. I think it is the best combination of speed, wx capability, comfort, and economy in its class.... for operations from one IFR airport to another with a max of 4 people. "But" and sorry to be blunt, I think anybody who operates this airplane into a 1600 foot strip needs his head examined. Yes it can be done but there would be absolutely no margin on either takeoff or landing. Our SOP was a 3000 foot field as a min and every take off was 0 flap with a 100 knots rotation speed(blueline on a VG machine) with selecton of the gear to up as the decision point (i.e. with gear down both throttles must be closed and you take your lumps straight ahead, with gear coming up takeoff is continued and engine failure handled as an in flight emerg)

Bottom line buy an Islander if you want to go into the really short strips.
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Old 10th May 2008, 01:42
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Thx for thoughts

Been away or a few days, but yeah, Lifeisgood & BPF, I take your point(s). I haven't, in fact, done ANY flying in a 340, let alone off a short strip. So I'll have to save the head examination till I get the new beast and decide where to base it Nor am I here to argue, so, um, I won't! I'm just researching the question, at this stage, and comparing viewpoints. Particularly on the issue of why you can't just cut power immediately to prevent a VMC roll on takeoff.

There are a whole lot of reasons for why I'm asking this, and yes, I hear ya. I guess I wasn't suggesting catlike reflexes, so much as normal reflexes, but being wide awake to the possibilities of emergencies, as opposed to getting complacent. And, like it or not, there ARE differences in pilot abilities, currency and so on, so some minimum field lengths for commercial operators, for instance, have to be a minimium that works across the board. But I hear you guys, loud & clear. Thanks for the input.
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Old 10th May 2008, 21:41
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One of the problems with training for the multirating is all engine failures are

1) expected, and

2) always total.

Unfortunarely the real world is rarely so accomadating. Many engine problems manifest themselves as engine surges ( can be intially difficult to detect as airplane yaws back and forth) or partial failures ( potentially leading to shutting down an engine producing power ) or prop under or overspeed. While in theory rotation below VMC followed by engine failure can be survived by instantly reducing power on the operating engine, I would suggest that in practice most pilots are going to wind up as a smoking hole in the side of the runway

By the way one of my pet peeves is frequent discussion on this forum about how pilots will evaluate the situation and then use their judgement to decide how to deal with an engine failure during takeoff. Airlines have a defined go no decision point with a set of unvarying actions before and after that point.

This came about after many crashes proved preprogrammed responses to these kind of emergencies was the most effective way to deal with an engine failure during the takeoff sequence. So what makes PPL's think they have more cognitive power to dal with a bad situation, than a 30000 hr airline pilot who will only utilize rote preprogrammed responses

Thar is why the owner and I adopted the proceedure I outline in my earlier post. It is the closest we could think of to duplicate the airline SOP.
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Old 10th May 2008, 23:00
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Vmc is an aerodynamic control speed.
No, Vmc is a certification value. The actual aerodynamic control speed varies with a number of factors, ranging from CG to density altitude, flap position, gear position, and gross weight.

A large part of this discussion (which really ought to be centered on the 340, rather than aerodynamics or procedures) has been about the ability or efficacy of preventing a Vmc roll following engine failure while taking off at speeds less than the minimum single engine control speed.

The airplane will not, as a rule, snap roll inverted and crash. Control may be lost faster than you think, however. Regardless, why would you want to find out? It seems the point of the questioning is to see if you can take off at a ridiculously slow speed and still manage to pull back both engines in time to prevent a roll. Rather than do that, how about using a longer runway and flying the airplane at a speed which does maintain control...and flying the airplane instead?
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Old 10th May 2008, 23:57
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All too true. I've done an engineering type degree and my Pa was an engine designer. When an engine is just about to go t*ts up, it always seems to be running better than ever. Two stroke petrols deliver most power when just so weak they're about to seize. My Land Rover (recent toy) gets really nicely blippy on the throttle when it's about to run out of fuel (must re-time the injector pump).

Never underestimate the power of the buggers to bite you on the arse.

It 'can' be argued that twice the possibilities, four times the problems.
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Old 11th May 2008, 02:39
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Pet peeves...

...and one of my pet peeves is the argumentative tone that things can take here on PPRuNe, so, I'm not going to argue. I'm here for education....

Re the parallels between airlines and private flying, I agree to a point, and particularly on the idea of pre-programmed responses to certain events. I try to emulate that approach as much as poss in my own flying. But let's not forget the airlines aim for - and achieve - FAR higher safety levels than we do, at a certain cost. If we were to aim for the same levels of safety, we would only ever fly out of balanced fields, we'd have a fully trained co-pilot on each flight, we'd have turbine engines with ample excess thrust so a serious climb rate is attainable on one engine, we'd have professional flight despatchers, and we'd have....er....an airline

But no, I don't maintain I have more cognitive power than experienced airline pilots. Just a much, much wider range of situations to assess, sometimes, and less SOPs. More privileges. More freedom. More risks.

At private level, therefore, we have the privilege of assessing and operating to our own levels of risk. So we don't, in fact, always fly out of balanced fields, we certainly can't climb out on one engine if we're flying a single and the engine quits, etc.

I'm asking about the concept of lifting off slow, and then if the engine fails, pulling the other one and accepting a controlled crash, cos I'm trying to work out whether I could or should operate into my own private strip. I fly a lot of single engine STOL Ops, (on a different field - my one is actually very long for a normal single engine aircraft) and I guess I can't really see the difference between flying off a short field in a single, and accepting that if the engine fails in the first 5-10 seconds after airborne you're in deep trouble, and doing the same in a twin. Double the engine failure risk, of course, but neglible + neglible = close to negligible, doesn't it? I'm guessing that we're talking about a 5 second period between rotation and a reasonable VMC-proof speed. Again, I'm NOT here to argue - I'm here to learn. And nor am I attached to doing so - I'm just trying to figure it out. But that's the context, and the reason I'm asking...
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Old 11th May 2008, 04:11
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Hey mate

Listen mate, put a sock in it.

The 340 with RamVIís and VGís has a published time from takeoff roll to 100 kts of 15 seconds at GTOW. The time frame from VMC speed to Blueline, which is VYSE (also 100 kts), is about 6 seconds. The most critical timeframe is those magical seconds when you are still earthbound and accelerating through the VMC speed and the wings are starting to fly. The problem is the little bugger wants to fly like a blooming pigeon. Around 75 to 80 kts the wings just come alive like Elton John in front of a grand piano. Your flight instructors have beat into you the need to keep the bird on the ground until the wind going over the rudder reaches at least 91 kts. They did this so that in the event one of the engines craps out there will be enough wind over the tail to give you a bloody chance of surviving the mess. Now if your nose wheel is still on the ground around this time (speeds from 70 kts to 90 kts) you will still have some directional control if you lose an engine. If you pull the nose wheel up to soon, say at 75 kts, and you then lose an engine, it would be arse over elbow mate. You see, the bloody wind would not be strong enough to give your rudder, thatís the tall thing sticking up at the rear of the aeroplane, enough counter force to offset the asymmetric force of a 335 hp engine four foot off your centerline trying to yaw the nose over to that ditch next to the runway. The safest thing to do is stick to the plan, published rotation speeds, balanced field length, plenty of recurrent training and a heavy dose of common sense. If you do all of these things your friends will think you are simply brilliant.

Last edited by Lifeisgood; 11th May 2008 at 15:04.
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Old 11th May 2008, 04:46
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But let's not forget the airlines aim for - and achieve - FAR higher safety levels than we do...
Heaven forbid that you seek for,or train to a high level of safety. You don't seek argument, and that's no argument. You have absolutely NO excuse for failing to seek the highest possible level of safety. Moreover, you have every responsibility to do so. That's your job description as PIC, in fact.

But no, I don't maintain I have more cognitive power than experienced airline pilots. Just a much, much wider range of situations to assess, sometimes, and less SOPs. More privileges. More freedom. More risks.
As a private pilot you hold more privilege than the holder of an ATP? Really?

No doubt from your questions and comments you take more risks. That's nothing of which to be proud.

I'm asking about the concept of lifting off slow, and then if the engine fails, pulling the other one and accepting a controlled crash, cos I'm trying to work out whether I could or should operate into my own private strip.
You're asking the wrong question.

The real question should be what length runway you need to depart in order to achieve adequate takeoff speed and distance to enable safely handling the situation if an engine quits. If you're asking if you can handle one quitting while attempting to climb out or takeoff below Vmc, you're asking a stupid question. There really is such a thing as a stupid question. What you're really asking is "If I do something stupid, what are the chances that I'll be fast enough to save myself from my own stupidity?" Which of your instructors taught you to take off below Vmc?

Not that it's not possible to do by any means...but certainly the inexperience offered in the way you ask and your tone suggests that it's not something for you. Of course, you also sound like you intend to do as you please, without regard to what others may have to say.

But let's not forget the airlines aim for - and achieve - FAR higher safety levels than we do, at a certain cost. If we were to aim for the same levels of safety, we would only ever fly out of balanced fields, we'd have a fully trained co-pilot on each flight, we'd have turbine engines with ample excess thrust so a serious climb rate is attainable on one engine, we'd have professional flight despatchers, and we'd have....er....an airline
What makes you think an airline must operate with a balanced field? A balanced field is one in which the accelerate go distance equals the accelerated stop distance, and this is very seldom the case. Rather, a rejection speed is computed which establishes a maximum speed to which the flight can accelerate before recognizing the problem and rejecting the takeoff. If the resulting stopping distance approximates the required takeoff distance, it's merely a coincidence.

You shouldn't be taking off, however, unless you have the ability to recognize the problem, and reject, and stop in the remaining runway, or stopway.

The issue of a first officer is largely one of aircraft certification and the regulations under which the flight is conducted. There's no question that in a highly complex, advanced aircraft, a SIC can be not only necessary, but immensely helpful. However, you make a poor comparison. Your aztec vs. a B747, for example. Consider also the complexity of operations, and the kindof flying you do may not require it. This does NOT mean you are excused from operating at the highest level of safety, and maintaining the highest level of proficiency. You have that full responsibility; operating privately does NOT excuse you from that.

Flight dispatchers are an operational requirement, and not all airlines use dispatchers. Some use flight followers, and not all of them are professionals. You, however, have the same responsibility in full to calculate your performance, know your fuel, your weather, your distances, your climb rates, and your capabilities before you go. Don't try to excuse yourself to a lesser level of safety merely because someone else isn't making the calculations for you. Moreover, regardless of who makes the calculations, the PIC is always responsible for them.

You don't need a turbine engine to act safely. Nor do you need it to assess takeoff performance or plan for it.

You could do that sub-Vmc takeoff in a turbine powered airplane and achieve the same results...if you're below Vmc, it won't matter if it's turbine or piston...pushing the power up will only aggravate your problem, and the fact is that your problems at that point are only compounded. So again, your comment really has no relevance to the conversation here, nor is it an excuse for acting unsafely.

I get the distinct impression that no matter how many people tell you not to go jumping into a higher performance airplane with a little more complexity, and taking it off Vmc, you're going to keep on asking until someone tells you it's okay. Anyone who doesn't is being "argumentative."

I guess I can't really see the difference between flying off a short field in a single, and accepting that if the engine fails in the first 5-10 seconds after airborne you're in deep trouble, and doing the same in a twin.
Therein lies the problem. You're already flying an aztec, you said. You shouldn't have to ask this question.

You're in deep trouble only if you fail to plan accordingly in the single. Your takeoff should be planned such that you already know where you're going to go and what you're going to do. You're going to be landing at a slower pace with far less mass energy, with a much lower stall speed, much lower touchdown speed, and better slow speed landing characteristics in the single; you can glide much more comfortably, farther, longer, and have none of the inherent dangerous characteristics that take place in the twin.

You may have no choice but to retard the good engine when a failure occurs in a light twin. It happens. However, especially in an airplane such as the 340, you should be planning your takeoff such that your weight, takeoff distance, and obstacle clearance area and departure area mean you don't have to. If you plan your takeoff by intentionally departing from such a short strip that you have zero options and your game plan is to put yourself in an emergency situation below the minimum control speed, then you've already decided to live a mistake before you ever start the engine. Starting with the fact that you've already placed yourself in a position where control may not even be possible.

Add to that the fact that aircrat such as the 310 and 340 use tip tanks with additional mass in the tip tanks and once a roll starts you may not be able to stop it.

Double the engine failure risk, of course, but neglible + neglible = close to negligible, doesn't it?
There again is a big part of your problem. You're assuming, guessing. Your condemn the airline operation for it's high level of safety, which is a foolishly mind-blowing concept in it's own rite. However, safety need not be the purview of the airline pilot alone, nor the corporate pilot only...it needs to be yours. The difference between you and the professional pilot is that the professional pilot plans the takeoff with a failure in mind, not hoping that it doesn't. Forget professional...the responsible pilot plans in advance for each contingency, and thus plans for the safe outcome of the takeoff regardless of whether the engine fails or not. You don't need to be flying a transport category airplane to do that.

And to answer your question, negligible doesn't equal negligible. Your engine will either run, or it will not; that's a one out of two chance, and it doesn't get any better the longer you fly...or the more engines you carry. You have that opportunity every single takeoff, and had better be planning for it. Not just assuming it's such a slight risk it probably won't happen. When it does, in the twin you not only lose 80% of your available thrust, but the remaining value is fighting to take control away from you.

Strive to eliminate risk, not embrace it.

I'm guessing that we're talking about a 5 second period between rotation and a reasonable VMC-proof speed.
The problem is that unlike having a failure occur at a speed above Vmc where you have the luxury of losing airspeed all the way to the minimum control speed...when you lose the engine below Vmc, you can't accelerate to Vmc. Adding more power only aggravates the problem. That leaves you in a regime where your ONLY choice is to reduce power on the good engine because you have no more aerodynamic control authority. Often this speed occurs close to the stall speed, which will also be the case if you're attempting to depart from a very short field near minimum control speed...and you can get there in a big hurry as you slow when the first engine goes. You have to recognize and react to the situation (an inexperienced pilot will invariably attempt to push the power up, rather than retard it, and handle the directional control with aerodynamic controls alone), and then correctly apply reduction of power on the good engine.

In the meantime, you're applying opposite rudder to the failed engine, and opposite aileron. You're already slow, at a high angle of attack, and at maximum takeoff power. The lowered aileron on the side of the bad engine increases the local angle of attack, increases adverse yaw, increasing the effects of the failed engine, as well as potentially causing a stall along the section of wing occupied by the aileron. The yaw is made worse, the roll is made worse. As the wing starts down in the 340, additional rotational inertia is imparted to the fuel in the tip tanks, making the turn and the roll even harder to stop. Additionally, as the wing with the good engine still has airflow, local lift is created which isn't available on the side with the bad engine, increasing the roll. Further, as the yaw occurs, the wing with the good engine moves forward increasing lift, while the airflow over the retreating wing decreases lift, further aggravating the roll. Even if you pull the power, you may continue to roll once it's started. How far, how fast, really depends on some of the factors previously cited (including CG, flap position, gear position, weight, density altitude, etc. If you're near the ground at the time, you may not have to roll very far before you catch a wingtip, and you may be lacking the performance to climb much to avoid it. Your time to recover is further reduced.

Rather than find out when it's too late, don't put yourself in that position to begin with. You needn't be an airline pilot to be safe.
SNS3Guppy is offline  
Old 11th May 2008, 05:52
  #17 (permalink)  
Thread Starter
Join Date: Feb 2006
Location: US
Posts: 77
Thx everyone

OK. Enough things being taken out of context here to see this discussion isn't going anwhere. If it seriously seems as though I was "condemning" the safety culture of the airlines, or not trying to minimise risk myself, I guess I need to work on my writing skills -or qualify everything I say with so many modifiers & caveats that the meaning gets lost. But this isn't a legal thesis we're writing, it is, or was, an educational discussion, for me anyway. Ain't the anonymity of the internet wonderful? You can argue amongst yourselves. I'll think seriously about the issues raised in the thread though, and thanks to all, particularly the earlier posters who said what they had to say without the testosterone haze getting in the way. Sock duly placed. Seeya.
lostpianoplayer is offline  
Old 11th May 2008, 06:21
  #18 (permalink)  
Join Date: Oct 2005
Location: USA
Posts: 3,218
OK. Enough things being taken out of context here to see this discussion isn't going anwhere... You can argue amongst yourselves... Seeya.
That's pretty much what I figured you'd say.

So far as out of context...you were quoted. Not taken out of context.
SNS3Guppy is offline  
Old 11th May 2008, 11:57
  #19 (permalink)  
Join Date: Dec 2001
Location: FL, USA
Posts: 2,609
Some of you need to relax a little behind that keyboard.
...insert arrogance......
Not everybody is as experienced as "we" are.
...turn off arrogance...

There is no such thing as a stupid question, but there is such a thing as a stupid answer.
Why don't we simply try to answer and educate?
B2N2 is offline  
Old 11th May 2008, 15:34
  #20 (permalink)  
Join Date: May 2008
Location: 63005
Posts: 12
Good Morning

To SNS3GUPPY, very well said!

To B2N2, no arrogance intended, just concern that some soul was not listening to good advice. Line one of his post referred to looking for advice.

To Lostpianoplayer, flying a light twin like a 340 is a joy, please keep safety number one.

I for one enjoyed the exchange; conflict hones the skills and allows everyone to reassess their values and opinions. As pilots it is these values and opinions that dictate our actions, or lack of actions. If we do not express disapproval of an unsafe procedure, what kind of pilots are we?

Lifeisgood is offline  

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