Well, during my time on FJs I had two engine shut-downs/failures on twin-engined aircraft (Tornado) and two on single-engined aircraft (Hunter). Only one MB tie. :}

It's an interesting question. The Tornado GR1/GR4 having been in service for over 25 years I would think that the number of real single engine landings is not trivial. My experience is in line with fin's although more failures (due to more flying hours :} ). I wonder if any ginger beers have a view on this...

I would say that there are maybe two or three single engine landings a month at least.

One thing to bear in mind though is that if you have two engines and you have a problem indication on one of them you can do a single engine approach and not risk using a potentially dodgy engine.

On Tornado a large number of single engine approaches were for transitory engine vibration which on further investigation turned out to be the detection system inducing a signal and not a problem with the engine at all. Lots of single engine approaches when not required but would you want to take the risk of an engine failing on you at a critical time?

Happy to say the system was modified so the number of spurious VIB captions has dropped.

I lost one of 2 donks just 25miles South of Baghdad when the locals on the ground weren't friendly (not a brown-job pongo for miles).

Happy with 2 engines that day as I limped into Kuwait.

QED?:ok:

Twin engines cost rather more for equivalent size, and design around the a:mad: end of the aircraft is trickier.
Most twin-jet fighters - the Jaguar and F-5 are exceptions - are twins because there was no fighter engine big enough to do the mission with a single when they were designed. (Even the classic Bug had 32k thrust at service entry, much more than any modern fighter engine of the day.)
Dave is a single because it's STOVL. Making it a twin would have been insanely complicated. Also, unless you can sort out the asymmetric issues in powered lift, an engine problem in STO or VL is more dangerous with a twin than with a single (because it will turn upside down very fast) and with two engines it is twice as likely. Very early on, the Navy wanted their version with two F414s, but "studies" were done which "proved" one engine was just as good.