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trevh
22-10-09, 20:40 PM
Hi
I have seen a Sirocco on Utube, the machine looks very good. Has anyone flew one?

Bob T
22-10-09, 21:41 PM
Few of them still around this neck of the woods. My mate scrapped his about a year ago. Trouble with that one was that it had had a rough life and when you start doing bodge repairs over previous bodge repairs, you start to worry a little.

Ginge
23-10-09, 10:46 AM
I wish, I have spoken to a guy that used to fly one of the older models, he claimed that it flew like a dream and that it was capable of soaring.

Having said that the older ones suffered from a bonding problem in the elevator. This caused a couple of accidents that put me off, the new ones however have a re-designed elevator to address this problem. The wing is also changed structuraly, this gets away from the wire braced wing and it now has airfoil strut bracing. So even less drag, I'll bet that make the soaring performance even better. Also the spoilers are replaced with conventional ailerons so control is likely to be crisper

At last years SPLASH show Paul of TLAC, the importer and also the maker of the Sherwood Ranger kits had one on his stand with the new wing and tail on show uncovered so that you could see what had been done. I believe that he is planning to be there again this year, so it will be well worth a look, it's also worth while have a word with Paul as he is a real straight guy that knows his business.

If I had the cash for a 2nd aeroplane I think that would be it, a 3 axis open cockpit pusher with the cockpit positioned for a great view that looks stunning, near perfection

Ginge

Jeremy
23-10-09, 16:02 PM
I agree, Ginge, it is a lovely little aeroplane.

The tail problem was principally a consequence of flutter, although this wasn't that obvious from the early failures - they were assumed to be a result of a lack of rigidity in the tail boom, plus poor skin bonding on the stabiliser. The original all-flying horizontal stabiliser wasn't well mass-balanced, which was the principal problem. When new they were OK, because the friction in the pivot was enough to damp it, plus the potential flutter problem only affected a few aircraft anyway, due to fairly wide variations in horizontal stabiliser mass between aircraft. Once the pivot got worn, then the possibility of flutter arose for some aircraft, as the damping friction was reduced.

The manufacturer came up with a modified tail with a mass balance, that cured any potential flutter problem. Curiously, and rather perversely, UK regulation added to the problem. As the Sirocco was orphaned, in as much as there was no UK approval holder once the original importer disappeared, there was no way to get the manufacturers mod legal here. As no one in the UK was around to get this mod approved to Section S, UK Siroccos weren't fitted with it. At least one fatal accident occurred here long after the mod had been accepted pretty much everywhere else.

To be fair there were a few quality issues in other areas of the airframe as well, so all told it is probably a good thing that the design has been completely revised by the new manufacturer. From what I've seen the new Sirocco looks much nicer than the old one. If it makes it into the SSDR category then I think it should sell well.

Jeremy

Ginge
23-10-09, 17:04 PM
Thanks for that Jeremy, that is a lot more detail than I had heard, and I wasn't aware that the principal cause was flutter. I remember reading the reports on the last accident and came away with the idea that the problem was to do with bonding.This was probably due to my misreading of the report, so thanks for putting me straight

I knew that this country had a different solution to the problem than those abroad due to the aircraft no longer being supported here, although I understood that although out of production there was an element of support to those in France.

That they are back in production with another company with the problems having been addressed must be good news

Ginge