Can we put the myth that singles are as safe as twins to bed now?

I also take issue with the "twice as likely to lose an engine", you are just as likely to lose an engine, you just have twice the engines to lose. One does not mean the other. Also even in drift down mode in a OEI scenario, being able to make it to a preferred spot with a lesser rate of descent can make a huge difference in survivability.
 
Well, it's more than just a few minutes.

Let's take my trip example. I crossed the mountains from KGTF to KPAE. MEAS the most direct route were 12k, the whole way. Didn't go that way for icing. With my load, I don't know if I could've maintained 12k on one. Certainly not with mountain waves on the downdraft. Also, there were segments of 75 miles or so with no airports.

Now look at my alternate path, the southern route that added miles. The first 150 nm were 13k MEA - same deal. Took me over an hour with the headwinds. After that, I was lower and yes, it gave me an advantage.

Spare vacuum pumps and alternators can be added to singles, so it really comes down to the benefit from the second engine at staying above the rocks. In a piston twin to get what I consider a meaningful advantage out there (meaning you can maintain MEAs until you get to the nearest airport), you need to be in a higher powered one with turbos. The low powered naturally aspirated ones (Seminole, etc.) I'll state are worthless, but I think they're worthless planes in general.
 
Another consideration is the time spent over inhospitable terrain. Since we are picking nits. A twin will usually be faster so exposure time is less.
 
Henning said:
I also take issue with the "twice as likely to lose an engine", you are just as likely to lose an engine, you just have twice the engines to lose. One does not mean the other.
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Yeah it does. If you have one chance in 100 hours of losing an engine in a single, you have 2 chances in that same 100 hours in a twin because you are operating them at the same time.

I've flown over and in the Rockies in both a single and a piston twin and didn't necessarily feel "safer" in the twin. But maybe I didn't think about it or analyze it nearly as much as people here seem to think about it. I feel safer in a jet but obviously stuff happens to them too...
 
Do not know if twin is 100% needed. A piston single turbo, pressurized, with 25k ceiling should do the trick (like the Piper Mirage). Really the safe way over the mountains is not so much number of engines, but the old saying altitude is your friend. That requires at minumum O2, likely pressurized, must be turbo piston, if not turbine.
 
Everskyward said:
Yeah it does. If you have one chance in 100 hours of losing an engine in a single, you have 2 chances in that same 100 hours in a twin because you are operating them at the same time.

I've flown over and in the Rockies in both a single and a piston twin and didn't necessarily feel "safer" in the twin. But maybe I didn't think about it or analyze it nearly as much as people here seem to think about it. I feel safer in a jet but obviously stuff happens to them too...
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It's not quite double, but close. A 5% failure rate per engine over a given time will result in a 9.75% chance of failure in that same time period with two engines. A 1% failure rate for one would be a 1.99% for two.
 
drotto said:
Do not know if twin is 100% needed. A piston single turbo, pressurized, with 25k ceiling should do the trick (like the Piper Mirage). Really the safe way over the mountains is not so much number of engines, but the old saying altitude is your friend. That requires at minumum O2, likely pressurized, must be turbo piston, if not turbine.
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Yes. At 25,000 feet in a PA46 if you lose an engine, you still have a 12:1 glide ratio. You're obviously not going to aim for a peak, so if you take an average ground altitude of let's say 12,000 feet (which is also being generous because you would have time to aim for a valley airport), that is 30 miles to find a suitable landing location. So realistically, using your brain and choosing the right location to glide towards, you're talking about 30-50 miles to finding a place to put down. In the mountains! A whole lot more in the flatlands of course.
 
BobThePilot said:
Yes. At 25,000 feet in a PA46 if you lose an engine, you still have a 12:1 glide ratio. You're obviously not going to aim for a peak, so if you take an average ground altitude of let's say 12,000 feet (which is also being generous because you would have time to aim for a valley airport), that is 30 miles to find a suitable landing location. So realistically, using your brain and choosing the right location to glide towards, you're talking about 30-50 miles to finding a place to put down. In the mountains! A whole lot more in the flatlands of course.
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In VMC, that works, SVT gives you some benefit in IMC, without SVT in IMC, you're not doing particularly well.
 
EdFred said:
It's not quite double, but close. A 5% failure rate per engine over a given time will result in a 9.75% chance of failure in that same time period with two engines. A 1% failure rate for one would be a 1.99% for two.
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That's some shakey math right there!

IF you are saying that there is a 5% of a single engine over time (your number, not mine, but we can work with it), let's say that over time means in the say 1700 hours of the engines TBO life, now let's say it's a 3 hour flight over said mountains, that gives us a 0.00176% chance of a 5% lifetime of engine failure on said 3 hour flight. Now multiply 0.00176 times 0.00176 and that gives you a 0.00000311% chance that both engines in the twin would go out at the same time on a 3 hour flight in a twin.

For the math genius' out there, sorry if my math is a bit off
 
Silvaire said:
So why not a Quickie? Engine out and only one dude dies, no cargo lost. What's the point for a twin, just a quest to enlarge one's carbon footprint for no apparent reason?
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Seriously, you don't see any situations where a twin is more advantageous? I love my Mooney for its speed and economy, but if I had to fly to the Bahamas at night there is no question I would take a twin over any single. Even in daylight I'll take the twin! I've made the trip many times and each time I wondered if this is the time I'll be swimming with the sharks :)
 
Zhunter said:
That's some shakey math right there!

IF you are saying that there is a 5% of a single engine over time (your number, not mine, but we can work with it), let's say that over time means in the say 1700 hours of the engines TBO life, now let's say it's a 3 hour flight over said mountains, that gives us a 0.00176% chance of a 5% lifetime of engine failure on said 3 hour flight. Now multiply 0.00176 times 0.00176 and that gives you a 0.00000311% chance that both engines in the twin would go out at the same time on a 3 hour flight in a twin.

For the math genius' out there, sorry if my math is a bit off
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My math is fine, your interpretation is incorrect. No one said the chances of losing both engines. The numbers were based on the chance of losing a single engine out of two operable ones.

The math is 1 - (1-failure rate)number of engines) in losing a single engine out of however many you are running.
 
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Ed

I misunderstood your point then.

Personally I would only look at a twin that could maintain or gain altitude on one engine.

Why have redundancy that is not practical at twice the maintenance cost? Just me tho.

I'm a fan of the hated inline center thrust twin, the C-337 :)
 
Zhunter said:
Ed

I misunderstood your point then.

Personally I would only look at a twin that could maintain or gain altitude on one engine.

Why have redundancy that is not practical at twice the maintenance cost? Just me tho.

I'm a fan of the hated inline center thrust twin, the C-337 :)
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In reality with a non-turbo'd twin in the mountains, you are going from a 1000fpm descent in a engine out with a single, to a 200-300fpm descent in a twin with one engine out. It can give you the ability to "outrun" some terrain, but you most likely are still coming down.

And it's OK, after reading it again, I wasn't entirely clear with my post.
 
EdFred said:
In reality with a non-turbo'd twin in the mountains, you are going from a 1000fpm descent in a engine out with a single, to a 200-300fpm descent in a twin with one engine out. It can give you the ability to "outrun" some terrain, but you most likely are still coming down.
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The only thing I would add is that you are most likely also going to descend on one engine in a number of turboed twins.
 
Everskyward said:
The only thing I would add is that you are most likely also going to descend on one engine in a number of turboed twins.
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As I only have 0.7 in turbo'd twins I will accept your statement without argument. :D
 
EdFred said:
As I only have 0.7 in turbo'd twins I will accept your statement without argument. :D
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I flew a turboed C-320 for over 2,000 hours, and I was pretty unimpressed with its single-engine performance around here. But I don't have a lot to compare it to as far as piston twins are concerned. I have about .5 in a Twin Comanche and maybe 20 hours in a Duchess.
 
Zhunter said:
I'm a fan of the hated inline center thrust twin, the C-337 :)
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I haven't done a lot of research into that plane, but it's an interesting design. Other than people not making sure the rear engine was running, and ready, for takeoff, what was the major issues for that design not being popular?
 
LoneAspen said:
I haven't done a lot of research into that plane, but it's an interesting design. Other than people not making sure the rear engine was running, and ready, for takeoff, what was the major issues for that design not being popular?
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Here is a good site for you to learn about 337's: http://www.337skymaster.com/messages/index.php

I think it is a bit odd looking when compared to other twins, it has poor baggage storage (goes in cabin), but has great useful load. As for the rear engine, just look at your tach, it won't lie. Btw, it will climb on either single engine, but better on the rear.

I just love that plane for many reasons. Lotta haters out there tho :goofy:
 
Of course, given the poor engine reliability stats for the Malibu fleet, that doesn't seem like a great option for the Rockies if you're looking for engine reliability...
 
In the 80s, I flew quite a bit with a buddy who demonstrated turbo commanders. If I were flying between say.....Boston and Baltimore at night and the engine quit in my mooney, regardless of height, I would rather be in a turbo commander with an engine out ( which he demonstrated often) with him flying it.
 
LoneAspen said:
I haven't done a lot of research into that plane, but it's an interesting design. Other than people not making sure the rear engine was running, and ready, for takeoff, what was the major issues for that design not being popular?
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slow, unreliable, cramped, noisy. Other than that it's great.

If someone says they are "fan" then they have either never been in one or are an enthusiast, sort of like MG enthusiasts who will insist that an MG is a fine daily commuter even as they are walking the rest of the way to work.
 
JHW said:
slow, unreliable, cramped, noisy. Other than that it's great.

If someone says they are "fan" then they have either never been in one or are an enthusiast, sort of like MG enthusiasts who will insist that an MG is a fine daily commuter even as they are walking the rest of the way to work.
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I never had trouble keeping my MGs running, making them stop was another subject...:rofl:
 
JHW said:
slow, unreliable, cramped, noisy. Other than that it's great.

If someone says they are "fan" then they have either never been in one or are an enthusiast, sort of like MG enthusiasts who will insist that an MG is a fine daily commuter even as they are walking the rest of the way to work.
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Oh geez...you're not going to believe this, but I know a guy who has a Skymaster and recently got his MG up to par enough to drive it. I often see it at the airport.
 
JHW said:
slow, unreliable, cramped, noisy.
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Here we go again. The thing in your avatar is slower, has way less cabin space, of questionable reliability, and not much quieter. But no matter. Let's kick C337, the twin that can actually fly on one.
 
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Henning said:
With a much better ability to choose where to crash and into what. Makes a big difference in survivability.
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Not as big a difference as a BRS would. :yikes: Sorry couldn't resist.
 
From what I've read, the engine failure rates for the PA-46 and the Cessna 210 are just about equal. I don't hear folks bad-mouthing the 210. What's with all of the hatred towards the Malibu? Don't get me wrong, only a fool would fly a single at night or in serious IFR, but that's just my opinion.
 
JHW said:
slow, unreliable, cramped, noisy. Other than that it's great.

If someone says they are "fan" then they have either never been in one or are an enthusiast, sort of like MG enthusiasts who will insist that an MG is a fine daily commuter even as they are walking the rest of the way to work.
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'73 and later pressurized improved that a lot, NR headsets pretty much take care of the noise problems unless you want to live in the past.

175 knots is not too bad with useful loads in the 1,500 pound range.

Some have 6 seats, I'd go 4 and use the space for baggage.

Hate all you want, centerline thrust twin with safety of two engines and much easier to control with an engine out.

But fine, just go ahead and hate ;)
 
Dead Stick said:
From what I've read, the engine failure rates for the PA-46 and the Cessna 210 are just about equal. I don't hear folks bad-mouthing the 210. What's with all of the hatred towards the Malibu? Don't get me wrong, only a fool would fly a single at night or in serious IFR, but that's just my opinion.
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Ahhhmen brother!
 
Henning - what _do_ you do for a living that has you bounding over the US all the time, at a moments notice, with your "tools".

This does sound like "the most interesting pilot in the world". ;)
 
dans2992 said:
Henning - what _do_ you do for a living that has you bounding over the US all the time, at a moments notice, with your "tools".

This does sound like "the most interesting pilot in the world". ;)
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Yacht captain/engineer. The tools are my plane tools.
 
Uh OH. I am considering my first airplane purchase. Thanks for confusing me further. LOL
 
etemplet said:
Uh OH. I am considering my first airplane purchase. Thanks for confusing me further. LOL
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Yeah, that's what I thought when I first got interested in GA, and came here.

Lots to learn, including sorting out opinions from facts. I'm opinionated, too, in many areas, so it all evens out, LOL.
 
Zhunter said:
'73 and later pressurized improved that a lot, NR headsets pretty much take care of the noise problems unless you want to live in the past.

175 knots is not too bad with useful loads in the 1,500 pound range.

Some have 6 seats, I'd go 4 and use the space for baggage.

Hate all you want, centerline thrust twin with safety of two engines and much easier to control with an engine out.

But fine, just go ahead and hate ;)
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no hate here, juet objectivity. When we ditched the two 337's that were in our fleet of 20-something liught twin freighters and replaced them with 2 more aztecs, the fleet availability ticked up noticeability. 337 downtime ran 3-4X that of a 310 or aztec in the same service (delivering boxes to semi-improved strips)

the market doesn't lie, there are no bargains. And you can't give away a 337 whereas the seneca, baron, travel air, twinkie, have also taken a beating yet hold considerably more value in comparison.
 
Apelsin Elise said:
Here we go again. The thing in your avatar is slower, has way less cabin space, of questionable reliability, and not much quieter. But no matter. Let's kick C337, the twin that can actually fly on one.
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the travel air is a small 4 seater, it doesn't masquerade as something more. In reality the cubic feet of space are about on par with the 337 and the mpg are far better.

i learned to fly in a 337. did pipeline inspection, fish counting, freight delivery in them. They worked great for pipeline in remote areas where cost was not an issue. And I'm told it was a very stable rocket and gun platform. Neither of those attributes have much to do with taking the kids to the beach reliably and economically.
 
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