Aeromaster

[Nigel R]

Few pictures from earlier. 

 

But if a better back drop than my kitchen tiles!

 

 

 

 

Edited July 20, 2021 by Nigel R

[Nigel R]

To draw this thread to a near conclusion (at least for me) my Aeromaster has finally seen the sky.

 

Noise check first... the 81 with a flexi pipe plus silencer, and a 14x6 APC, was just under the 82dbA limit. It was all prop noise - the side & rear readings were around 6db lower.

 

And then the maiden. I went off at 3/4 throttle as there is lots of go, and that was plenty to pull her upwards with no drama. A bit out of trim (despite checking things over about a thousand times I still ended up with the rudder and elevator slightly off) but otherwise good. Might be a touch tail heavy - there was a tendency to "sit up" but that may simply be the trim not quite there. A couple of loops and rolls to check things out a bit more, all good, roll rate is probably too slow for some but I found it perfectly ok given the type of airframe this is.

 

I decided not to push things and came in after about five minutes for a drama free landing. At a small amount of throttle this thing will descend fairly quickly, but perfectly controllable - standard biplane stuff with all that drag, so, steep approach, over the threshold, pull back to flare - great.

 

Then the motor quit while idling on the runway and I couldn't get the bugger started again ?

 

So. Engine will come out - again - to double check my cleaning was thorough enough. If I cannot get the thing going on the bench after another strip down, then I do have a backup plan in the shape of a normal (non pumped) OS 91 which is about an ounce heavier and will fit the same mount and exhaust hardware and likely do about the same rpm on the same prop.

 

Trials and tribulations etc.

[Trevor]

Congratulations on the maiden Simon! I hope you get the engine sorted soon.

[Nigel R]

After a minor saga, I have fixed the 81 now.

 

After checking it over I found a lot of fuel coming from the regulator. Another disassembly / reassembly failed to sort it. At that point I figured I would just replace it, there was only so much time and effort I wanted to spend looking into what appeared to be a faulty regulator.

 

Sadly no more spares were available for the pumped version. Instead, plan B - I ordered a new carb body and rotor from the non-pumped version. All other carb parts are the same - so it was then a straightforward disassembly / reassembly exercise to get the carb converted to the standard version. The pump was removed and the backplate nipple blocked with a plugged bit of fuel tube.

 

A bench run confirms it is now running like a champ with the new setup so will soon be back in situ and the airframe back in the air.

[Nigel R]

Well that was fun!

 

Got three good flights in today with the motor on song. I felt much more confident and gave it a good wringing out. At 7lb there is a good amount of power from the 81, not quite "endless vertical" but sure is plenty of go. Flicks are crisp, rolls smart (even with two ailerons) and stall turns look good. She has a good presence in the air, too. Short on rudder authority but I can get more movement. And she is dead easy to land, hold a touch of up in and adjust the sink rate with throttle, it is textbook stuff.

 

I need to get a smoke system fitted!