[Porsche-O-Phile]

In a conventional light twin, loss of either engine (50% of your thrust) can result in a loss of up to 90% of your performance. I won't get into the details, but a simplified explanation is that performance is a function of EXCESS thrust horsepower, not net thrust horsepower. When one engine goes away, the excess THP remaining is very minimal above and beyond what's necessary to keep the aircraft flying and in some cases, isn't even enough to do that (depends on variables like weight, altitude, aircraft configuration, pilot skill, etc.)

With the Skymaster, the biggest advantage (as has been said) is that if one engine fails, you lose the asymmetrical thrust. However, you are still in trouble - you're STILL losing virtually all of your excess THP and will have highly impaired performance.

For the record, assymetrical thrust is not that big a deal in a conventional light twin if you know what to do (i.e. configure the aircraft for "zero sideslip") and execute according to training. The problem with this is that most non-professionals don't practice single-engine technique enough. Multi-engine rentals (or ownership) is very expensive and the mentality of a lot of the people with enough $$$ to fly them is often "I know what I'm doing", which results in a dangerous combination (an old instructor of mine often correctly quipped that the most dangerous pilot in the world was a doctor who flew twice a year and owned a Baron or a King Air. . .) Lots of factors involved, but the MOST important thing in flying twins is to practice the single-engine technique often so that the remaining engine doesn't "fly you to the crash site".

That said, I always feel more comfortable in a twin than a single. In a single, if the engine quits, you WILL be on the ground in a few minutes inside some defined radius (depends on your glide range). In a twin, you have considerably more options provided you know what the hell you're doing, don't panic and execute properly. It's ultimately all about the training.

There's a reason most commercial aircraft have multiple engines.