I am having trouble with engines on my Islander: Sometimes, after significantly reducing power on approach they are totally unreponsive to an increase in throttle with drastic consequences.
I am 90% certain that it is not carburettor icing - the problem seems to occur if the RPM drops out of the green for any length of time. Then pushing the throttle leavers forward has no effect and I end up in the sea off St Mary’s. It is strange that it does not seem to happen on every flight.
I’ve never experienced this in almost 2 years and i’m not seeing it reported. You say your 90% sure its not icing, but have you tried adjusting the carb heat?
It will be the carb ice. The carb ice model on this Islander is very aggressive. It’s also not a case of just increasing the carb temp until the needles are out of the danger zone. If you notice reduced performance give it full carb heat to clear the icing until the expected performance returns.
Keep a close eye on the carb temp gauges. You’ll be surprised to find that they often stay just inside the yellow arc with no heat applied, even on a warm day. I find that putting my mouse over each lever and rolling in just 2-3 notches of heat will take the needles above the yellow arcs without compromising performance.
In the real world, leaving the heat on full thins out the air going into the engine and degrades performance. I’m not sure how well this is modeled in the Islander, but I figure why take a chance on flight issues.
I was flying today in tropical Queensland, Australia - YBRK to YBMK.
I confess to not checking OAT, but at around 3,000ft I would be astonished if it was ≈10C.
Had it on AP and walked away for a bit - came back and the manifold pressure had plunged - throttle and props on full - air speed down at 80kts and falling.
Nudged the carb heats - didn’t make any difference. Manifold pressure didn’t budge.
Had to land in a paddock about 10-15nm short of YBMK.
So, what’s the likelyhood this is a carb heat problem - or something else?
Once the signs of carb ice happen in this aircraft you need to apply full heat to remove it else you’ll be loosing the engine(s). Best to keep an eye on the carb temp gauge and use smaller amounts of heat to stay out of the yellow danger zone in the first place. It’s probably the most aggressive carb ice aircraft in the sim.
As soon as I have the engines running, I use my mouse wheel to roll in 2-3 notches of carb heat. Full carb heat without carb ice will reduce performance, but I’ve never had an issue with just a little.
I have the same issue - and like others (above) I apply some carb heat as a matter of routine.
But somewhat depressingly, as did @Kamahhn, I find that once the carbs have iced up to the point of engine power loss the effect cannot be reversed without shutting down the engines and restarting.
It’s caught me out a few times, usually on approach when it is the most untimely.