Monday, 10 September 2018

Aerobatics FUUN

After winning the Club grade earlier this year I decided to make the move up to Sports grade. Although that didn't mean I had practised anything since April before entering this latest comp.

I hadn't even looked at the Known sequence until 2 weeks before this comp but still decided to enter anyway and treat it as a learning/training exercise.

So an intense 2 weeks of practise followed with me trying to fly every day (British weather permitting). First off learning the manoeuvres that were new to me and then trying to put everything together in the sequence and practise it with different weather/wind conditions. After that I focussed on practising UnKnown sequences - something I'd never done before.

At the comp I had the misfortune to pick 2nd out of the hat for the flying order so I wasn't able to learn anything each time from watching the other competitors before me.

The first sequence was a low overall score for me, I got massively off heading on the first figure and then hard zeroed the second and third figures as a result of that. Despite flying the rest of the sequence quite well it was impossible to recover from those early errors. A small mistake costs you dearly in Aerobatics.

Staying with my earlier theme, in the two UnKnown sequences, I managed to hard zero the highest scoring figures again! This hurt my score a lot but I still managed to finish in 6th (from 13) and 7th respectively so that made me feel not so bad at all. I had expected to be in the bottom 5 for the whole comp and to have two flights finishing in the middle of the pack was better than I expected.

Where the Twister is most lacking is in the Immelman where it loses lots of energy so the roll off the top always looks a bit 'soft'. I have tried to enter this figure faster and pull harder at the beginning and that seemed to help but an Extra 200 it is not.

I had a lot of fun and learnt a lot from the two days. I'll have a more serious attempt next year.

Sequence cards, videos and results of each sequence flown are below.

Known Sequence

1st UnKnown Sequence

2nd UnKnown Sequence

Overall Results

Monday, 3 September 2018

Twister with D-Motor

The owners of OE-CSI (formally G-CDKJ) Bert and Wilfried, have sent me some pics of their D-Motor install so far.

When it is up and flying it will be interesting to hear of the performance figures and if there are any issues. I did consider the D-Motor when building mine but it does not offer inverted oil so I did not go with it.

Wilfried also contacted me to let me know that they had the same issue as me with elevator play, on the Port side only. This was at 200 hours.

Tuesday, 21 August 2018

Oil thermostat failure

On the last leg of my month long trip I noticed that the oil temp was not coming down as it normally does once in the cruise.

It stayed at 100 - even though I was at 7,000 ft.

I put it down to a particularly hot day and perhaps a strong inversion over the UK which made it unusually warm at altitude, which it was.

However on my next flight, after the 50 hour service, it was a coldish day and I did not climb for long but the oil got hot again (106 - the hottest it's ever been) and refused to come down below 100 when in the cruise.

I thought this must be the thermostat (in the oil filter mounting plate) which had failed and was now stuck in the closed position. This has also happened to Pete Wells - while he was in Spain in the summer - not good!

I contacted the UK UL Power agent, Jonathan and after a discussion with him he agreed that I should replace the part and see if that was the problem.

UL Power were good enough to send me the replacement part which arrived this morning. I fitted it this afternoon and then took the Twister for a test flight.

I'm pleased to say all is now well again and the oil temps are back to their old self. Not even hitting 100 in the climb - despite a hot day again today - and then coming down to 90 in the cruise - as it should.

Lucky this did not happen to me while I was overseas as it would have grounded me while I waited for the new part to arrive.

After the old thermostat/oil filter housing was removed

New housing at left and other old fittings to be reused at right

Old thermostat. Note the spring is not seated the same as the new one - maybe this has something to do with it failing?

New thermostat spring - note the more even seating of this one.

Old housing to the left and new one to the right. The valve also appears to be slightly more open at ambient temps on the new housing too.

Sunday, 12 August 2018

Belgium, The Baltics and Beyond

I spent the month of July touring in the Twister.

The journey began in Belgium with a great weekend of banter and beer at the EFLEVA (European Federation of Light, Experimental and Vintage Aircraft) fly-in where I was asked to give a talk on my Oshkosh adventure from last year.

It was good to catch up with Johan and we took an early morning Twister formation flight together the next day.

Then it was off to Germany to visit Paderborn Haxterburg and the home of the Twisters. Another memorable formation flight followed with Matthias and Ingo in Twisters 2 and 3.

The next day I flew to the north eastern part of Germany, to Anklam. To visit the Otto Lilienthal museum and the following day take the short flight up to Peenemunde to visit the V1 and V2 museums.

The next day I headed east to Kaunas in Lithuania, via Gdansk in Poland and skirting the Russian border of Kaliningrad to the north.

I then spent a few days in each of the Baltic countries - which I fell in love with. Each one has it's own unique flavour, plenty of history, culture, interesting foods and they are all very affordable to visit. Highly recommended!

While in Riga I visited the Tarragon factory and took a test flight in the prototype Tarragon - a very impressive machine.

I flew into Tallinn International in Estonia - as there are no small airfields within reasonable distance of the capital. 

After that it was north through Finland, overnighting in Kemi. Then up to Lakselv in the north of Norway, flying via Europe's northernmost point, Nordkapp, which I did not actually get to see as it was covered in coastal fog.

As it is so far north, morning civil twilight in Lakselv begins on 26 April and evening civil twilight begins on 16 August. In between these dates it being light all the time.

By flying around Nordkapp I was at 71 degrees North Latitude, much further north than my trip from last year which was just 67 degrees north in Kangerlussuaq, Greenland. I think this is the most northerly point a Twister has ever been?

After that there was only one way to go, South. I headed to Bodo for two nights. One afternoon spent looking around the excellent National Air Museum of Norway, which is located at the Northern end of the runway in Bodo. The next day was a highlight as I took a short flight over to the Lofoten Islands which are quite spectacular. I stopped in Leknes airfield and took the bus to the Viking Museum.

The next day I flew two long legs, the first south to Trondheim for a fuel stop then east across to Stockholm where I stayed with my friend Chris for 5 days and a well earned rest.

Heading back west to Oslo after that and then across to Bergen after 2 days in Oslo. 

My partner Tracy flew over to Bergen and we did a road trip around the fjords for the next 4 days.

A short flight south to Stavanger via the spectacular Lysefjord and then it was across the north sea to Eshott for fuel and then south back home to Old Warden.

What a great trip and I was so lucky with the weather.

44.2 hours flown in total. Fuel burn average 14.8 litres per hour with a total burn of 654 litres.

The only problem being a flat tyre in Bodo after landing. Not sure why it went flat but I think maybe the pressures were a bit low.

Pics and a few vids on this link: 

Route map

The F word

No not that one. Flutter.

Recently I noticed that the elevators had a little bit of play in them. 

The port side was much worse than the starboard. 2.5mm measured at the trailing edge but less than 1mm of play on the starboard side.

The play was all coming from the Hex in the elevator, the female part of the elevator connection, which slides onto the ali male hex on the elevator tube.

Consulting Matthias about this he said just to wax up the metal part and then put flock into the fiberglass hex part and slide the tailplanes back on and let them cure.

So that's what I've done and this has taken all the play out.

When I was on my recent trip in the cruise at altitude I found I could induce a little flutter of the tailplane by very gently 'polling forward' on the joystick. Not good. 

I went for a test flight yesterday after fixing the play and I'm pleased to say - no more flutter.

Something worth checking.

Video of the port elevator play below.

Tailplanes off for the elevator hex fix.

Metal hex and surrounding area all waxed up so the flock does not bond to it.

The fibreglass hex inner was sanded and then cleaned with Acetone before applying a thin layer of flock to take out the play. The hex was also inspected carefully to see if there was any cracking or other damage but all was well.

Sunday, 5 August 2018

Twister Database

I thought it would be a good idea to put together a database of all the Twisters that have been completed and have flown (or are just about to).

If anyone finds any errors or omissions I'd be pleased to hear from you.


D-MTMH. Number 2.

D-MTMN. Number 3.

Diesel Twister. Registration unknown. Damaged in accident, no longer flying.

F-WTVI. Written off in post crash fire.

G-CDKJ. Sold to Germany, currently being fitted with a D-Motor and re-registered as OE-CSI.

G-FUUN. Number 28. First flight 11th December, 2016.

G-JINX. Damaged in crash landing, currently being rebuilt to flying status.




G-TWSR. Number 5.



G-ZWIP. Number 4.

I-A908. Italian registered, Built by Termikas in Lithuania.

LY-BDA. Electric Twister, built by Termikas and Silence Aircraft. Resides in Switzerland.

LY-ING. No longer flying due to owner health issues.


N600ZF. Number 6.

N787M. First kit sold and constructed.

OO-162. Number 31. First flight 19th June, 2016.

Registration unknown. Fitted with D-Motor. Flight status unknown.
D-MTMH. Twister Number One, the original prototype. Note Twister Number two uses this same rego. This airframe is no longer flying.