« Reply #5 on: Aug 08, 2019, 9:34 pm »
I had the top of a spray grease can - quite a thick one - go thro Britannia's thrust fan recently.

It managed to vibrate off the engine and fall under the guard, got in the belt and then into the fan. I was doing a full power check at the time ....  Noise like a gunshot, bits everywhere.  Shut down and retrieved the shrapnel from the lawn - checked the fan - no visible damage or marks and a bit of cosmetic surface damage to the cowl. 

A previous time that happened - about 35 years ago - the entire assembly, belt, fan and flow straighteners went out of the back of the thrust duct. 

We have indeed progressed !

« Reply #4 on: Aug 08, 2019, 9:07 pm »
If you spend enough time 'out there" then statistically you'll get burned.at some point.  I've had a few problems but, apart from one time, all have been repairable to get me home.  Last close one was this Feb when I'd just completed a trip around Bute (done around 50 miles) and stopped on a beach to camp overnight. 

I was walking around the back of the craft and noticed some pink drops on the skirt and thought, that's odd.  Turned out that BOTH hose clips holding the main coolant hose under the engine had failed (I double-clip almost all coolant hoses for safety).  The hose was still in place. held there only by the pipe bend pushing against the engine frame!  If it come off then ALL of the coolant would have been instantly lost and the engine cooked within a minute or so.  The clips were stainless (well. turned out not quite, the screw corroded away on one and the screw retainer on the other (neither bits were actually stainless!).
Turns out that double-clipping is only a good idea if you actually check on them regularly!  Obviously, one had failed earlier and I hadn't noticed.  Still, it shows that you can't rely on anything ultimately!

« Reply #3 on: Aug 08, 2019, 7:17 pm »
Now that shows how far we’ve come. Back in the day a flip flip spoils your day. Now a similar sized chunk of plastic  goes “thunk” and the fun goes on.

That’s the benefit of running fans more slowly - enough reserve strength to cope with the unexpected.

Ian Brooks
Gloucester, UK

« Reply #2 on: Aug 08, 2019, 9:19 am »
35 years ago, preparing to hover around Anglesey, and my sizzer in law kicked off her flip flops into the floor of the craft as we set off for a demo jolly.
I opened up (suckie suckie)-------------BANG  ::)
All blades had exploded as they quickly munched thro the sponge, so my world first was put on hold--- and still holding------  :-X

                                                      If it can - it WILL
Memories are BETTER than Dreams---"Capn" FLINT

« Reply #1 on: Aug 08, 2019, 12:45 am »

Flying recently, I heard a bit of a 'thunk' but was unsure what it was.  I was negotiating some muddy moguls at the time I assumed (wrongly) it was perhaps a rock striking the bottom of the hull.
When I got back on the slipway I realised that a 5 litre plastic fuel can that I keep low down in the footwell no longer had its screw-on filler nozzle. The type you put through a loop of plastic on the filler cap and then poke the other end through a hole just beyond the carry handle.
It had gone through the fan guard and been sliced/diced by the 6Z blades. Not a mark on the blades whatsoever, but found only about a 100mm section of nozzle in the plenum. Good job it was a thin plastic nozzle!!!!!!    :o

So, one to watch. Even when we check for loose objects be aware that a 'bumpy' ride can loosen off previously considered stored items.

Keep on flying ladz
A BHC Marlin mk3 and Coastal Pro  Owner