Why Twins Aren't Safer than Singles

[jesse]

One thing I always find interesting is how many twin owners can tell you how they've had to shut one down, or they've had catastrophic failures, etc, etc. Interesting mostly because I know very few single engine pilots that have ever had an engine fail. I can't figure out if some twin owners are just flying junk because they can't afford to keep both engines properly maintained so that's why they seem to lose them every third flight or if it's because they're just overly excited about shutting them down to justify their expense.

It's kind of like 4x4. I'm always excited to put my truck in 4x4 simply because I paid extra for that feature. In reality 90% of the time that I go into 4x4 I'd had been fine with a 2x4 truck.

 

[Ted]

One thing I always find interesting is how many twin owners can tell you how they've had to shut one down, or they've had catastrophic failures, etc, etc. Interesting mostly because I know very few single engine pilots that have ever had an engine fail. I can't figure out if some twin owners are just flying junk because they can't afford to keep both engines properly maintained so that's why they seem to lose them every third flight or if it's because they're just overly excited about shutting them down to justify their expense.

It's kind of like 4x4. I'm always excited to put my truck in 4x4 simply because I paid extra for that feature. In reality 90% of the time that I go into 4x4 I'd had been fine with a 2x4 truck.

Sometimes it's precautionary shutdowns, but for me it's always been accessory failures rather than engine failures.

You probably also see a lot of twins that fly more than singles, which provides more exposure time for a failure to occur.

 

[Henning]

Pilatus. For one, anyway. And not just cargo.

Ok, anything without a PT-6 or other turbine hanging on it?

 

[LDJones]

Back a few years ago when Felix was talking about buying a P-Baron, he claimed its capabilities were closer to a Lear than a piston twin. Hence, LearBaron.

Someone, I have no idea who, then made this video.

http://www.xtranormal.com/watch/7953387/learbarons-explained/

That's pretty funny...except for picking on the Duke! (And, yes, I've seen the Duke cartoon!)

 

[Ted]

That's pretty funny...except for picking on the Duke! (And, yes, I've seen the Duke cartoon!)

As I've told you, I'm just jealous.

 

[Skylane81E]

Ok, anything without a PT-6 or other turbine hanging on it?

You bet, no turbine required. The redundancy the FAA desires is not the engine

 

[Skylane81E]

That's pretty funny...except for picking on the Duke! (And, yes, I've seen the Duke cartoon!)

But the tails fall off, making them less safe than a single

 

[Everskyward]

One thing I always find interesting is how many twin owners can tell you how they've had to shut one down, or they've had catastrophic failures, etc, etc. Interesting mostly because I know very few single engine pilots that have ever had an engine fail. I can't figure out if some twin owners are just flying junk because they can't afford to keep both engines properly maintained so that's why they seem to lose them every third flight or if it's because they're just overly excited about shutting them down to justify their expense.

It's kind of like 4x4. I'm always excited to put my truck in 4x4 simply because I paid extra for that feature. In reality 90% of the time that I go into 4x4 I'd had been fine with a 2x4 truck.

Dunno. I have about 4000+ hours in piston singles and never had a complete engine failure. I might have had about 5 partial losses of power but none were bad enough to cause an off-field landing. I have about 2000+ hours in piston twins and had one complete engine failure at altitude but I was able to get it restarted.

 

[Henning]

One thing I always find interesting is how many twin owners can tell you how they've had to shut one down, or they've had catastrophic failures, etc, etc. Interesting mostly because I know very few single engine pilots that have ever had an engine fail. I can't figure out if some twin owners are just flying junk because they can't afford to keep both engines properly maintained so that's why they seem to lose them every third flight or if it's because they're just overly excited about shutting them down to justify their expense.

It's kind of like 4x4. I'm always excited to put my truck in 4x4 simply because I paid extra for that feature. In reality 90% of the time that I go into 4x4 I'd had been fine with a 2x4 truck.

I know lots of people who have lost an oil line or other accessory and started pumping oil out of the engine, most of them bought an engine if they didn't make a runway in the next few minutes, a couple of them did precautionary shut downs in hopes that they would make the ground before the fire started. Engines rarely fail, accessories fail all the time. My case I lost 3 oil lines in 2 years because I had a batch of junk new ones from when I bought the plane with crappy 'counterfeit' fittings. After the third hose, I just replaced them all.

Trusting your plane not to break down is like trusting your computer not to crash. Do you trust your computer not to crash, or do you back up your data? BTW, your 4x4 truck costs you 2-4mpg every day you drive it for those few times you need it, no different from owning a twin in concept.

 

[Skylane81E]

How about we sum this up?

Why can a twin not be as safe as a single?

Human factors.

 

[LDJones]

But the tails fall off, making them less safe than a single

Not with the right duct tape they don't!!

 

[Skylane81E]

Not with the right duct tape they don't!!

Name brand will hold anything together

 

[wabower]

Bottom-line results are identical. Twin driver shuts one down and lands at the nearest airport. Single driver just lands at the nearest airport. Trying to impute the coulda-woulda-shoulda or Henning's "this is how much I saved" nonsense is like listening to my wife's post-mortem analysis of a shopping trip.

Just fly whatever blows your skirt but don't try to justify one as being better or safer than the other. No matter which you choose, the overwhelming evidence will always show that the accidents are caused by the Indian, not the arrow.

Sometimes it's precautionary shutdowns, but for me it's always been accessory failures rather than engine failures.

You probably also see a lot of twins that fly more than singles, which provides more exposure time for a failure to occur.

 

[jesse]

I know lots of people who have lost an oil line or other accessory and started pumping oil out of the engine, most of them bought an engine if they didn't make a runway in the next few minutes, a couple of them did precautionary shut downs in hopes that they would make the ground before the fire started. Engines rarely fail, accessories fail all the time. My case I lost 3 oil lines in 2 years because I had a batch of junk new ones from when I bought the plane with crappy 'counterfeit' fittings. After the third hose, I just replaced them all.

Trusting your plane not to break down is like trusting your computer not to crash. Do you trust your computer not to crash, or do you back up your data? BTW, your 4x4 truck costs you 2-4mpg every day you drive it for those few times you need it, no different from owning a twin in concept.

I don't fly my airplane without a parachute.

As to other airplanes, I jump into a lot of random airplanes I know very little about and depart into single engine IMC all the time. Is there risk? Sure. But that's the real world. I don't live in fear of risk. I personally don't care if it has one engine or two engines or twelve engines. If it's a job that needs to be done I do it. With each situation I look at the risk, analyze it, decide if I'm willing to accept it and I either do or don't.

Bottom-line results are identical. Twin driver shuts one down and lands at the nearest airport. Single driver just lands at the nearest airport. Trying to impute the coulda-woulda-shoulda or Henning's "this is how much I saved" nonsense is like listening to my wife's post-mortem analysis of a shopping trip.

Just fly whatever blows your skirt but don't try to justify one as being better or safer than the other. No matter which you choose, the overwhelming evidence will always show that the accidents are caused by the Indian, not the arrow.

Exactly. Yes it's possible that there are situations to where you'd be better off in a twin if you had to have an engine fail that day. But there are equal numbers of days to where you'd be better off in a single to where you wouldn't have had that other engine that just crapped out on you.

At the end of the day -- if you're REALLY interested in the safety overall as a fleet -- just look at the insurance costs.

But an individual is not a group of many individuals and results may vary. So buy whatever the hell you want and enjoy it If I could afford a twin I'd probably buy one too. At which point I'd be on here telling you how much safer it is

 

[Skylane81E]

Bottom-line results are identical. Twin driver shuts one down and lands at the nearest airport. Single driver just lands at the nearest airport. Trying to impute the coulda-woulda-shoulda or Henning's "this is how much I saved" nonsense is like listening to my wife's post-mortem analysis of a shopping trip.

Just fly whatever blows your skirt but don't try to justify one as being better or safer than the other. No matter which you choose, the overwhelming evidence will always show that the accidents are caused by the Indian, not the arrow.

Hey, there you go.

Odds are very, very good that if I do my job on both sides of the wrench I will never wish for a second engine.

Granted had my one "incident" happened in a typical twin it would have been less on an event as I wouldn't have been seated behind the loose cowling,

So there twins win!

 

[flyingcheesehead]

...and I think it depends on where you do most of your flying. If you do a lot of flying in western colorado then obviously a single will be safer than a typical light twin such as a Seminole.

Which glides better, a Seminole with an engine out, or an Arrow IV (the SE equivalent of the PA44) with an engine out?

Even the Seminole with its often-below-ground single-engine service ceiling will drift down a lot slower than a gliding single.

I'd rather have the Seminole, even out west.

 

[jesse]

Which glides better, a Seminole with an engine out, or an Arrow IV (the SE equivalent of the PA44) with an engine out?

Even the Seminole with its often-below-ground single-engine service ceiling will drift down a lot slower than a gliding single.

I'd rather have the Seminole, even out west.

Of course when that engine in that Seminole ****s out and you're drifting down into a mountain of firey death, albeit with slightly more time to think about your fate, you may decide that you'd much rather be in that Arrow with the right engine that's still spinning bolted on front.

 

[Challenged]

http://www.velocityaircraft.com/airplane-models-vtwin.html

 

[flyingcheesehead]

One thing I always find interesting is how many twin owners can tell you how they've had to shut one down, or they've had catastrophic failures, etc, etc. Interesting mostly because I know very few single engine pilots that have ever had an engine fail. I can't figure out if some twin owners are just flying junk because they can't afford to keep both engines properly maintained so that's why they seem to lose them every third flight or if it's because they're just overly excited about shutting them down to justify their expense.

I can't tell you either, but I've never had an issue in a single in the air that wasn't CFI-induced, but in only about 20 hours of multi flying I've had a partial failure.

 

[Henning]

Of course when that engine in that Seminole ****s out and you're drifting down into a mountain of firey death, albeit with slightly more time to think about your fate, you may decide that you'd much rather be in that Arrow with the right engine that's still spinning bolted on front.

Why do you consider the engine in an Arrow to be more reliable than the engine in a Seminole?

 

[jesse]

Why do you consider the engine in an Arrow to be more reliable than the engine in a Seminole?

I don't. But perhaps that Arrow would have been built with that right engine instead of the left and as a result you'd have never failed in the first place

In many situations in twin flying you're just as dead if one quits (like the scenario of being in an underpowered twin in the Rockies) and you're twice as likely to have one quit. I can write up some quick code to simulate that and run that "flight" a few billion times and the twin owner isn't going to like the results.

Point is...there is no fore sure answer. As a whole, the typical privately owned piston twin isn't going to be much safer then the typical privated owned piston single. The insurance companies agree. But a "whole" isn't the situation that happens..and you can't predict what that situation will be. So buy whatever the hell you want.

 

[Skylane81E]

I can't tell you either, but I've never had an issue in a single in the air that wasn't CFI-induced, but in only about 20 hours of multi flying I've had a partial failure.

I cannot speak to others but it has been my experience that as a percentage twin owners are more apt to want to defer engine maintenance than a single engine owner. I have heard the words "It doesn't matter, have a spare engine" more than once.

Back to human factors

 

[jesse]

I cannot speak to others but it has been my experience that as a percentage twin owners are more apt to want to defer engine maintenance than a single engine owner. I have heard the words "It doesn't matter, have a spare engine" more than once.

Back to human factors

I have as well. I think it's a larger problem than people are willing to admit to.

 

[Skylane81E]

I have as well. I think it's a larger problem than people are willing to admit to.

I do not know how large the problem is, but IMO every aircraft engine should be treated like it is the only engine on the plane. I would imagine that most, if not all the twin owners here would agree.

But POA and other aviation forums are not a random sampling of pilots, if you care enough to frequent such a place...

 

[gismo]

I asked them what my numbers were at 100, 250 hours ME. I don't recall off hand but they were still quite a but higher. More than 50% even with 250ME and the same hull value.

And I don't get where the 1.5% comes from. I'm at 3% on my single, with no more discounts coming. Avemco was still double what I am now with almost 1000 hours and 300+ in this plane.

Obviously the underwriters have been monitoring your posts here...

I think the cost for hull insurance is higher on twins, mostly because a gear up landing eats twice as many props and engines. But I think my hull premium is pretty close to 1.5% of the stated hull value.

 

[MachFly]

Which glides better, a Seminole with an engine out, or an Arrow IV (the SE equivalent of the PA44) with an engine out?

Even the Seminole with its often-below-ground single-engine service ceiling will drift down a lot slower than a gliding single.

I'd rather have the Seminole, even out west.

I think it's much easier to glide on an Arrow than a Seminole, the plane is just much easier to control. So you can focus a lot more of your attention finding a good landing spot and making a good approach to that spot, as oppose to making sure that you don't Vmc roll or stall and spin on the approach.

In addition if I know that I'm going to be screwed after an engine failure either way I'd much rather reduce the possibility of an engine failure by having just one engine.

 

[wabower]

I made two precautionary shut-downs in the 340 due to identical symptoms (rough). One turned out to be a clogged injector that required an hour or two labor to diagnose and fix. The other was a broken through-bolt that led to major engine work. Take your choice.

In both cases I landed at the nearest airport, but in one case I had to airline home.

One thing I always find interesting is how many twin owners can tell you how they've had to shut one down, or they've had catastrophic failures, etc, etc. Interesting mostly because I know very few single engine pilots that have ever had an engine fail. I can't figure out if some twin owners are just flying junk because they can't afford to keep both engines properly maintained so that's why they seem to lose them every third flight or if it's because they're just overly excited about shutting them down to justify their expense.

It's kind of like 4x4. I'm always excited to put my truck in 4x4 simply because I paid extra for that feature. In reality 90% of the time that I go into 4x4 I'd had been fine with a 2x4 truck.

 

[Henning]

I cannot speak to others but it has been my experience that as a percentage twin owners are more apt to want to defer engine maintenance than a single engine owner. I have heard the words "It doesn't matter, have a spare engine" more than once.

Back to human factors

Most people have no clue when their engine needs work until it craps out on them whether they fly a single or twin. The twin will forgive their ignorance by continuing the flight to a runway.

 

[wabower]

Conjecture. The answer is the same for both singles and twins. Maybe, but maybe not.

Most people have no clue when their engine needs work until it craps out on them whether they fly a single or twin. The twin will forgive their ignorance by continuing the flight to a runway.

 

[Skylane81E]

Most people have no clue when their engine needs work until it craps out on them whether they fly a single or twin. The twin will forgive their ignorance by continuing the flight to a runway.

Then I guess we don't need to do powerplant inspections then

 

[Henning]

Then I guess we don't need to do powerplant inspections then

Once a year that inspects next to nothing? How much safety does that buy? Besides which, tons of stuff gets overlooked by mechanics.

 

[Skylane81E]

Once a year that inspects next to nothing? How much safety does that buy? Besides which, tons of stuff gets overlooked by mechanics.

Yes, things do get over looked occasionally, yet I still find things wrong with engines on a regular basis.

Planes fly every day with out loosing an engine, what is a twin for? Same logic.

 

[Henning]

Yes, things do get over looked occasionally, yet I still find things wrong with engines on a regular basis.

Planes fly every day with out loosing an engine, what is a twin for? Same logic.

If you don't want to fly a twin, then don't, but just don't justify not for reasons that are inaccurate. People that will defer maintenance on a twin will do so on a single as well. I have heard "It'll be ok" or as they say in Aus, "She be right", out of SE owners as often as I've heard 'I have a spare' from twin owners.

 

[Skylane81E]

If you don't want to fly a twin, then don't, but just don't justify not for reasons that are inaccurate. People that will defer maintenance on a twin will do so on a single as well. I have heard "It'll be ok" or as they say in Aus, "She be right", out of SE owners as often as I've heard 'I have a spare' from twin owners.

My statement that a higher percentage of twin owners defer maintenance than single owners is 100% accurate for my sample size, I made sure not to paint all twin owners with that brush. Rescue your huggies from box canyon and lets move on.

And by the way, you are correct, I have heard the it will be ok nearly exactly as often as I have heard I have a spare,

I take care of far more singles though....

 

[Fearless Tower]

No matter which you choose, the overwhelming evidence will always show that the accidents are caused by the Indian, not the arrow.

I need to remember that....Arrows don't kill people....Indians do!

 

[JHW]

We're paying about 1.5% on hull value for the 310, 2.2% for hull + liability. Avemco has crappy twin rates, so I wouldn't talk to them. Talk to a broker who knows the market better.

Not always true. They seem to like travel airs for some reason. They've consistently given me the best rate.

 

[wabower]

Let's say a T210 owner buys a 340. Does his attitude regarding MX change on the same day he closes the deal on the twin, or sometime later?

My statement that a higher percentage of twin owners defer maintenance than single owners is 100% accurate for my sample size, I made sure not to paint all twin owners with that brush. Rescue your huggies from box canyon and lets move on.

And by the way, you are correct, I have heard the it will be ok nearly exactly as often as I have heard I have a spare,

I take care of far more singles though....

 

[Skylane81E]

Let's say a T210 owner buys a 340. Does his attitude regarding MX change on the same day he closes the deal on the twin, or sometime later?

Don't know, haven't seen someone go from single to twin. Just a general observation.

I doubt that someone who would go from impeccable maintenance to crap, but from mediocre....

The attitude need not change, but the actual decisions can.

 

[Ted]

Not always true. They seem to like travel airs for some reason. They've consistently given me the best rate.

Good data point. I've been with Chartis the past 4 years - they've consistently given us the best rates and good service. Although the service is really from my broker, and since I've made no claims, it's perceived service.

 

[Inverted]

I made two precautionary shut-downs in the 340 due to identical symptoms (rough). One turned out to be a clogged injector that required an hour or two labor to diagnose and fix. The other was a broken through-bolt that led to major engine work. Take your choice.

In both cases I landed at the nearest airport, but in one case I had to airline home.

And in both cases you didn't become an automatic glider, or a smoking hole. CRAZY!!!!!!!