Endurance - again!

The ESC is built into the rear pylon fairing.

Although it will only be running at low power it is in a small well insulated space so its 'bare' heat sink is mounted flush with the surface.

Next will be the motor and its fairing on the wing so it can be wired up to the ESC.

This has required some rather fiddly fitting and adjustment but the motor is fitted and wired up to the ESC.

And more to the point it has been tested and the motor goes round the right way!
Next the fairing ahead of the pylon spar.

The wing pylon complete.

The fuselage only has to contain the battery and on end it has a frontal area no bigger than the pylon spar.

I made a mistake ordering a 4 ch 'featherweight' radio from HK as the Endurance II direct drive aileron servos must be be on separate channels in order to individually set the servo centre points. Doh! :woohoo:
So a 6 ch radio will have to be cannibalised from another plane that only needs the 4 channels from the new HK one.

Unless of course I can use the spare rudder channel for an aileron but the DX6i has distinctly limited (and rather illogical!) mixing abilities.

The Orange Rx installed right through the pylon spar in its own little Depron box.

It has been done in this way so that it can (in theory!) be extracted forward for re-binding.
The sub trims have been used to "centre" each aileron and 50% differential has been added for good measure!
Slowly getting there!

At last a major step forward - a full airframe!

Everything works so next is to complete the nose so the battery can be used to position the CofG.
The complete airframe weighs 7.5oz (212g) - as does the battery!

Superb build. You are a depron artist!

Complete - less paint.

And it has flown - 3 times - but it will definitely need some paint as it is very hard to see 'edge on' at any altitude!
If anything it flies slower than the previous one but I expect it will need some adjustment to achieve the same minimum power condition.
With cool(ish) air and strong sun it certainly responded to the thermals but with a only a 'park fly' Rx (the first Endurance had a full range Corona 35meg) I did not want to find out what its range actually was! :woohoo:

Two more flights this afternoon as the weather is really good.
First lasted 31 minutes to get the 'feel' of how it behaved on a long(ish) flight.
Second shorter at 11.5 minutes but this time as a 'consumption' test with the 5000mAh battery fully charged. After the flight it took just 217mAh to fully re charge.
So (60/11.5)*0.217 = 1.1A average consumption
Not quite the 1A achieved by the first Endurance but pretty close considering it only had its maiden this morning!

Isn't it strange how gliders are always white, which is the worst possible colour for not seeing in the UK sky, closely followed by light blue!

For glass/carbon fibre gliders there is a reason as white bests resists the effect of the sun's radiation which eventually causes resin embrittlement.

Of course I knew that, Q, I was commenting on the colour, not the reason! :evil:

Now complete with a limited paint job.
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Under

On the grounds black stands out better against a hazy blue sky.

Nice this morning, although the westerly is supposed to get stronger, so two flights totalling 56 minutes, by which time my neck was beginning to feel the strain! :ohmy:
Lots of bumpy weak thermals about so smooth 'economic' flying was not really possible but it did not stop the Endurance II from climbing readily power off to the point I kept having to 'bring it down a bit' to avoid loosing it. Despite the black paint it is still pretty hard to see! :woohoo:
However it does not 'feel' quite right with the slightest air disturbance having a disproportional effect. An on-line calculator puts the CofG exactly where it is (27%) although its 'up swept tips' are a bit of problem to input!
What I need is a really calm day to determine exactly how it is flying.
ps
It looks like it is changing to a high over cast which will make it much easier to see!

Looking at the tail-feathers, they look very small for that short couple, combined with the large chord of the main wing.
How did you measure the t/p area?
Did you just take the flat area, or did you take the 'shadow' area - ie put a strong light vertically above and measure the area of the shadow? (The technical way, put the airframe in the flight attitude, and drop verticals from the leading and trailing edge tips of the tailplane, and 'fill in' the gap, then measure the area)?

To be honest there was no measurement.
The tailplane came from another powered glider that had a greater span (64") but a much higher aspect ratio and it was a bit of a handful in that too!.
Concerned at the broad wing chord I extended the boom by 4.5 inches.
Yes the horizontal area is probably only just adequate but for aerodynamic efficiency that is how it is intended to be.
It manages quite well in calm conditions.
If it proves to be too much of a problem I may substitute a more conventional cruciform tail.

You'd be better making the boom longer - go for 2.5 main wing chords. Look at a full-size glider for comparison - a very long fuz for a small tail.
The same problem occurs with a Vee, when working out the rudder/fin area. They need to be bigger than you think - shadow area again!
Making the boom longer also makes the nose longer for getting the c of g right.