Saturday, 25 March 2017

Visit to a fellow Twisterer

On Friday I flew down to see Tim Dews, who is based at a small strip in Wiltshire.

Tim bought Adrian Hatton's old Twister and is building another one too.

After quite a bit of chat we went for a fly together and it was my first time in formation with another Twister - great to see one in the air and Tim was throwing it around too. Demonstrating an avalance (flick roll at the top of a loop) which looks like a fun manouver to try out.


All the control gaps have been sealed in glider like fashion.

I noticed a huge amount of aileron trim on Tim's Twister. Since my aileron bearings have loosened up I now have virtually no trim at all on my ailerons.

Tim's panel has changed a bit since Adrian owned it.

Tim talks me through the panel.

Progress so far on his Twister. I can say for sure he is making a really professional job of it.
Beautiful work!

The trailer for his Twister (yet to be fitted out) is in the background.

A nice scenic flight back home. This is the White Horse near Westbury.



Wednesday, 22 March 2017

Official ICAO code for Silence Twister

After some work with the ICAO database people I have secured an official code for the Twister.

When filing a flight plan from now on use the code: TWST (From April 27th)

Previously you would have had to use the code: ZZZZ and put TYP/SILENCE TWISTER in the Extra Information section of a flight plan.

Hopefully air traffic will be a little less confused by us in the future.

The confirmation email from the ICAO database is below.


Dear Mr. McKee,
I would like to inform you that the ATDSG (Aircraft Type Designator Study Group) has now completed its review of all the material that you have presented and has allocated the following aircraft type designators TWST for the Silence Twister model. This information is now registered into the Aircraft Type Designator (Doc 8643) electronic database and will be sub sequentially published in the next edition of Doc 8643, which is scheduled for April 2017. I would like to personally thank you for bringing this model to our attention so that it could be registered into Doc 8643.
Manufacturer/Model                    Designator                         WTC                     Description
SILENCE Twister                              TWST                                   L                            L1P
Best regards,
Steve Laskie
Air Navigation Planning & Support Officer
OPS Section
International Civil Aviation Organization

New Camera mount, oil filter, aileron pushrod fairings and SPOT Tracker.

As you will see from the below screenshots and video links, I've built a new camera mount which now gives a forward view from the tail.

It seems to work okay but I think the prop wash is causing it to vibrate a little bit which sometimes makes the sky 'swim' with distortion as the cameras stabilising is pushed to it's limits.

This vibration is most likely coming from the plastic mount stalk itself as the carbon bit's I've made are very stiff. Nothing I can do about it really. Will see how it goes and maybe think of a better solution at a later date.

I also finally got around to fitting the aileron pushrod fairings - which are a Pete Wells mod. Fairly straight forward to fit, just use double sided tape (the good stuff - 3M). As I'm paranoid they could come off I also used Duct tape as a back up to secure them in place.

I've also invested in a SPOT Tracker and found a good place to mount it in the cockpit. The unit must have a good view of the sky to keep GPS coverage. It also needs to be removable so a simple velcro strap with foam underneath has done the trick. I will use it on any long trips and obviously it will be very handy on the Oshkosh trip - a very good way to track exactly where you are. It updates it's position every 5 minutes. There is also an SOS function on it which alerts the appropriate authorities so it provides a good backup to a PLB/ELT.

Nice of SPOT to colour coordinate their unit with G-FUUN too. :)

Regarding the oil filter - I have sent it to Patrick at UL Power for a closer analysis as Patrick admitted that it had more metal in it than normal. I will keep you posted as to what he says.

Now for some video with the new camera mount. 

A 4 point roll: https://youtu.be/n9Ajw2bLiOA

And some sustained inverted: https://youtu.be/teuas8DxdAI

4 point roll - still from video link above

Inverted - still from video link above
SPOT Tracker mounted on top of headrest

Colour co-ordinated Tracking device.

Aileron pushrod fairing

Double sided tape on the flanges and duct tape as a back up.

Front view. I have not noticed any performance benefit.

Rear tail camera mount made from Carbon. I laid up the curved portion directly on the tail then bonded on and reinforced the flat plate section later. Thin foam on the inside is to stop the paint getting scratched. The mount itself is 3M stuck in place and then riveted as a backup.

Mount in place on the tail.

Closer look. I think the vibration is coming from the flex in the plastic stalk part of the mount.

Looking forwards.


Wednesday, 15 March 2017

FUUN times

Video of a flapless takeoff, just to see how it feels. Doesn't take much more runway than with 10 degree takeoff flap. (I'm holding it down for the showboat ending after lift off.)

https://youtu.be/tl5ZLoFIH5U

More serious stuff coming soon.



Friday, 10 March 2017

Clipped wings no more

I got a phone call today from the LAA to say my Permit had arrived back from the CAA!

They posted it to me today so I should have un-clipped wings by Monday.

The world is now truly my oyster.


Monday, 6 March 2017

15 hr maintenance on UL engine

The 15 hour maintenance is all done and there were no problems.

As you will see below the oil filter had a fair load of crap in it.

The cylinder head torques were ok. 

The tappets all needed adjusting (tightening). The inlets were pretty close to correct but the exhausts were all loose. I put a pen mark on the top of the starter ring gear and alternator fan to show where top dead centre is as it's impossible to see the factory mark when it is in position vertically. 

I gave it a test run on Saturday and all was well.

Still waiting on the full Permit to Fly to arrive - I expect it will be another week or so.


Draining the oil - when I lifted the tail quite a bit more oil came out. It's a good idea to do this as the drain plug is positioned towards the front of the sump and if the tail is down you won't get all the old oil out.

Adjusting the tappets.

This was the worst section of filter.
The whole filter element. Click to see larger view.