Simshed Gnat Tail Flutter

dswanson · Post by **dswanson** » 20 Dec 2006, 18:30

Hi,

I took the Simshed Gnat out for a spin today and when I got carried away with the throttle a severe tail flutter started at about 350kt. You can see the elevator fluttering up and down and with a force-feedback stick, it took some controlling.

Anybody else seen this and more importantly, anybody know how to fix it ?

Chris Trott · Post by **Chris Trott** » 20 Dec 2006, 20:12

Turn off your force feedback. That's the source of the problem.

ianhind · Post by **ianhind** » 20 Dec 2006, 20:16

FS2004 didn't like FF joysticks - mine has long since been abandoned.

There are various compromise fixes around on a plane-by-pane basis, but as Chris says the easiest is to turn FF off :sad:

cstorey · Post by **cstorey** » 20 Dec 2006, 21:31

Interesting - I had exactly the same problem with the Hunter

dswanson · Post by **dswanson** » 21 Dec 2006, 17:27

Hi,

It seems a shame to turn off the FF, I have no problems with other planes. I also remember the same problem with DG's hunter but he fixed that. I downloaded the changed DFD files and it sorted it. I wonder what he did and can it be applied to the Gnat ?

Rich · Post by **Rich** » 22 Dec 2006, 00:24

dswanson, Iam the original author of the FF fix for DG's Hunter over 500 downloads I believe with no complaints and have fixed dozens of others including the Gnat.

Every aircraft I download is given a flutter test and is fixed if I intend keeping it as the Gnat.

I am afraid the advice given from the rather ample rectums to turn off FF is a load of cods wallop.

Fixing FF Flutter is easy and does not entail removing it altogether

Rich · Post by **Rich** » 22 Dec 2006, 00:30

Actualy the problem is in the way section 320 in the airfile is written 2 sets of figures need adjusting and it is fixed, after applying the fix I test to 50 kts over the max allowable if its ok then thats what I use

Chris Trott wrote:Turn off your force feedback. That's the source of the problem.

dswanson · Post by **dswanson** » 22 Dec 2006, 11:06

Rich,

Thanks for that, I couldn't really believe that the FF system alone was to blame.

Can you share your fix method ? I'm familiar with amending the airfile and can see a number of factors in section 320 but which ones are to be tweaked ?

Perhaps you could PM me if not willing to show this in the public forum.

Rich · Post by **Rich** » 23 Dec 2006, 00:22

dswanson, Have a look at this thread I posted last year the 2 relavent lines in Section 320 are highlighted in red and blue,.

Hope this helps

http://www.sim-outhouse.com/sohforums/s ... post102169

ianhind · Post by **ianhind** » 23 Dec 2006, 00:34

I am afraid the advice given from the rather ample rectums to turn off FF is a load of cods wallop.

Well no one could offer any advice on how to fix flutter with FF two years ago, and after searching various forums I dumped the Sidewinder 1.

Not least I was pi$$ed with M$ abandoning the support of their own branded hardware.