Oct | 2019 | G-MLSY

It’s been a month since we carried out the first part of the flight test. A couple of holidays and continued bad weather has prevented further testing but Monday and Tuesday both looked good so Rob made the trip down on Monday morning so we could finish it off.

After a cuppa we planned what we were going to do. Avionics testing on the first flight, the Airmaster and feathering on the second flight and during the third flight which would be for 2 hours we would test the autopilot and complete any outstanding general flight tests.

To ensure that we achieved the 15 landings required by the LAA to validate the flight test Rob suggested that we carry out some Touch and Go’s at Lydd EGMD. A quick call to them and we were set up for that on Tuesday.

All the flights were completed at the end of Tuesday at 16:03. We logged 15 landings with a total flight time of 7:31. During the flights all aspects of the the aircraft worked faultlessly.

The Airmaster was a dream to use and produced some very impressive results with maximum rpm for very sprightly acceleration and a very short take off run. Once Climb is selected we noticed a very good climb rate even at MTOW. The transition between different settings on the prop was very smooth and predicable. With the engine off and the prop feathered it reduced the drag to negligible rates which was reflected in the reduced descent rate achieved.
The engine ran faultlessly and never missed a beat. It was very responsive to throttle changes throughout the range.
The autopilot performed faultlessly too. It did everything that was asked of it. Tracking a flight plan, climbing or descending at a specific VS or to intercept an altitude. It even protected the aircraft by ensuring it didn’t fly outside the flight envelope.
The Dynon screens are clear and easy to read. They take a bit to get used to as they are not quite as intuitive as an iPad, but they worked very well with good aural warning annunciations coupled with the display of appropriate alerts.
The Bristell was lovely to fly. It was stable and had a good solid feel but very responsive when you need it. It settled on the ground during landings very nicely even in moderate turbulence. The cabin is very spacious and the seating is very comfortable. It felt that you could fly for hours and not get fatigued.

Overall I’m very happy with my decision to buy a Bristell. The options I’ve included have enhanced the end result and my decision to fit the Airmaster have resulted in an aircraft that’s a delight to fly.

So the flight tests are done and the paperwork is with the LAA. Now it’s a waiting game before I receive the permit to fly but hopefully it won’t be too long before I’ll be able to take G-MLSY for a flight myself and then take Karen for a few flights including a little tour around the Kent coast.

G-MLSY is a joy to fly and it was great to get back in the air.

One of the tests to carry out if you have a feathering prop is to switch the engine off, feather the prop and restart with a dive and then repeat with a starter restart. Both work faultlessly. Once feathered and trimmed for best glide we achieved and impressive descent rate as can be seen in the photo..

It never ceases to amaze me what you see from the air. Here a staggered river or drain reveals itself at height.

Dungeness Power station off the right wing tip. The landscape around here is quite barren.

Set up for a very turbulent final to ’03’ The Bristell handled very well and was very responsive even in these conditions. Touch & Go’s were really very easy. Land, dial up 10 degrees of flap, full throttle and away you go. On climb out with positive rate of climb, flaps away and switch the Airmaster to ‘Climb’. The rpm reduces to 5500 with no stress or fuss.

One of the things that we had noticed is the EGTs tended to be a little on the high side. During construction I made a decision to add exhaust wrap to the exhaust downpipes. This was to protect surrounding pipes and lines from excessive heat. However it seems to have an adverse effect and produce higher than expected EGT. This shows the EGTs with the exhaust wrap fitted.

I decided to remove the exhaust wrap and run the engine again. The EGTs are running up to 80 degrees cooler now so I’ve decided to leave them off now.

G-MLSY looking good after a thorough clean and ready for the next flight…

Yesterday we received an instruction from Bristell UK to remove the coolant thermostat if you had fitted one. They state that two Rotax 912 ULS engines have had to have cylinder no. 1 replaced due to overheating and they claim that the thermostat caused. With no other information it seemed sensible to remove it although now I effectively have a €250 aluminium 90 degree connector. Quite frustrating.