Some more flying of the Aresti 108 at the Firle Beacon on the South Downs, East Sussex yesterday. It's fairly light wind around 15-20mph but occasionally thermic and no ballast was necessary. Much smaller hill than Bopeep and in fact the bowl was the poorer one as the hang gliders were using the best one! So this really is showing the big 108 doesn't need a massive hill/conditions.
Greg Lewis flew then Dave Woods had a go and well, you can see the results! Greg tells me he then had difficulty getting it back off Dave! Dave is a 'top' classic acrobatic pilot and he put the Aresti 108 through it's paces- enjoy!
One of the characteristics of the Aresti 108 that has been commented on over and over that in the air it looks like it's flying slow. However pull the elevator and it does a tight loop, which you would not expect from that 'speed'. No doubt its a scale effect thing and it's actually going quite quick but the size just makes it look slower. So, the energy retention and needs a bit of adjusting too but of course this is what is making this plane so amazing to fly. It's graceful and still has plenty of oomp for manoeuvres.
Dave makes a tongue in check joke for James about the revised enlarged rudder still being too small, it's not but obviously Mr Woods wants to keep James on his toes! BTW, I'm told Dave never got out his own plane yesterday and Greg had to fly his Crossover because he could get another go with the Aresti 108!
Monday, 22 September 2014
Thursday, 18 September 2014
Aresti 108 video
The Aresti 108 flew yesterday at the Bopeep Hill in the downs
near Lewes, East Sussex . Conditions were much better
than the maiden just a few days ago and around 15-20mph. Only its 2nd
outing it was flown by 5 pilots including Greg Lewis, who nonchalantly handed
around the transmitter! Despite it’s size it’s actually very easy to fly with no
vices. The energy retention just keeps it going and she looks beautiful carving
big shapes. The roll rate is outstanding especially for a big plane and it was
even ballasted up with 1kg of fuse provision (12 slugs of 19mm, ¾’’, 35mm long
brass) making a total flying weight of approx 4.8kg. There’s approx another
1.4kg to go in the wings with a 610mm long 19mm round brass bar that wasn’t
felt necessary.
Here it is, a very honest unadulterated raw video shot with
Gro Pro on Greg’s head. You’ll get an idea of what it did but what isn’t conveyed
so well is the sheer size and presence not only of the airframe but those loops
and bunts are enormous!
The airframe shows no sign of stress, which is as well as
the joiner and spars are enormous and because the wing is thick and has a broad
chord, it’s not bendy or twisty. The fuse is also very strong especially along
the boom fin juncture with a full carbon except for the canopy area.
Proto radio tray built mostly in 6mm ply |
Production one will be moulded and factory fitted, but same principle and will add a huge amount of strength to the nose area. |
One of the features of the Aresti design is the 2 piece tail
and elevator design. The tails are very firmly held in place and no wobbly tail
plane as you’ll find in most all moving tail designs but more importantly pitch
control needs very little deflection only +/-8mm with 40% expo. This all
contributes to the energy retention and efficiency that the Aresti 108 is
showing. Aside from the deep sides it’s actually a very clean design. Even with
full size servos in the wing the covers are flush!
It clearly doesn’t need a gale or epic hill to do this and
looks so smooth it’s one of those rare planes that can make your flying look
better! The guys had a blast, what more could we have asked for so early on in
prototype testing. I have a feeling we are not far off, just minor installation
details to make the build pain free and linkages optimised. This is going to be
very easy to put together and thoroughly complete!
Aresti family! |
Monday, 15 September 2014
Aresti 108 maidened!
Aresti 108 prototype |
Most UK
slope fliers will have bemoaned the complete lack of wind for virtually 2 weeks
as we have been sat under high pressure- very unusual for the time of year and frustrating
indeed, as we had the new Aresti 108 prototype ready to fly. So seeing that
there was an end in the conditions yesterday we dashed across to the east coast
of Yorkshire, at Reighton Sands and the prototype was finally
maidened! Wind was light, only around 8-10mph but enough to prevent us from
having enough doubt or common sense (!) from lobbing off the 3.8kg prototype
for it’s first ever flight. However, CG was set at 130mm, about 6mm (scaled up)
in front of the position that we fly the Aresti 2m, which was our only attempt at any
precautions!
Big plane about to be launched, like a 1/4 scale but with low aspect ratio wings |
The elation as this big bird soared effortlessly away was blatantly
felt by all, except it seemed by the Aresti 108! She just majestically carved
through the sky in a rock steady path. Big planes just sit in the air so
steadily, it had presence and cut through the air with such authority. No
twitchiness, no bumpiness just creamy smooth progress. Sure we could have done
with much stronger conditions to show case its potential but after so much
anticipation it was enough to see vindication for building such a large
acrobatic slope plane. The size just brings another element, doubts about being
too big for anything other than flying in the Alps was
immediately dispelled. It doesn’t fly slower but the scale effect makes it look
as though it does and even on the coastal hill flown yesterday you could see
that it’s going to work on a lot of our hills!
It was also satisfying that the trims were left alone and no
changes made- even the thermal setting seemed about right as the camber really
made a difference to height gained. This was about the same ceiling as anything
else flown before. A dive to check the feel of the CG and yes it was nose heavy
which of course is no bad thing for a maiden flight. The roll rate was good but
the differential needed a tweak and the elevator with couple camber and reflex
was a tad too much, other than that the first ever flight. piloted by Greg
Lewis, was exactly what we hoped for. It’s just beautiful in the air with such
presence that got everybody’s attention as unusually the slope was quite busy- must be the break in the weather that got fliers out to the East Coast!
Low pass for the camera! |
This is a plane that has real presence in the air! |
Next it was my turn for a flight and we moved further round
to the North to get a better vantage of the light lift.
Greg Lewis holding- this shows a perspective of the size of this model as we walk towards a more northerly spot launch |
Now I’m just a
competent, average flier and definitely no acrobatic pilot but even in my hands
it made my flying look good. It was so smooth which now made my big cheesy grin even
bigger! It just felt so steady and coming close in, it whooshed past with a
sound unmistakable that this is indeed a big plane. It seemed to just plough
through and if anything, easier to fly than the smaller Schwing E and Aresti 2m
I’d been flying earlier. I had a Mobius cam strapped to my head to film the
flight but regrettably in the anxious moments before my flight I had it
pointing a little high so no great footage.
However, even in the conditions we
had which needed an efficient airframe, it could cover so much sky and cruise
along with ease which considering it’s fully symmetrical section I didn’t
expect quite so much efficient use of the lift available. I fly with the same
transmitter as Greg (but a different mode hence the prototype was set up on 2
transmitters with slightly different throws) and consequently had slightly
better settings for roll, although I had reduced elevator throws, discovered
from the first flight. This was approx 8mm up and down.
A few tweaks to the programming! |
As predicted for the forecast wind strength increased as we
got later in the afternoon and Greg took the Aresti 108 up again for it’s 3rd
and final flight of the day. 30g trimming weights were removed which put the
big Aresti at the same cg as it’s smaller brother. In addition the throws were altered in line
with my settings. The inverted flying was now pretty bang on. Stall turns with
rotation at the top from the massive rudder was impressively round and
seemingly in one spot- which was very gratifying as much work had been done on
this with 6cm (!) throw either way (30 degrees). One surprise was how tightly
it could loop without getting upset. The diameter looking quite small indeed!
All in all, a dream of a first day’s flying that really
could not have gone better. Overall the leaving impression was this plane has
so much presence- it’s going to be a show stopper in better conditions, I’m
sure and that’s exactly what an acrobatic plane should do!
We shall be test flying at various slopes, building on the
valuable information gained today. It might be near you! I keep you posted
here, as we’ll also be bringing along the Aresti 2m, Carbon Schwing and new
Electric Schwing hotliner prototypes.
All prototypes- Schwing E on 6s, Aresti 2m and Aresti 108- fantastic days flying! |
For those that want more info about the build of the
prototype, here they are:
Servos 6 x Hitec HS5496MH, full size 20mm wide and HV, used
on all surfaces, including Aero Tow release (well why not!) except elevator,
which used a Graupner DES 448 BB, 10mm servo mounted in the fin and regulated
with a MPX servo voltage regulator.
Fu-Fix bearing kit used on all servos (including rudder
servo mounted in the canopy area) except Tow Release servo.
Ballast in fuse is 12 of 19mm round, 35mm long brass slugs
approx 1kg. Additionally 19mm round brass bar 610mm long in wings, 1.4kg. Total
ballast provision is 2.4kg
Total ready to fly wt is 3.8kg and with full ballast 6.2kg.
Nose wt required to balance is approx 200g.
CG flown, 136mm from LE at root.
Full size Hitecs in the nose, rear rudder servo even has a bearing kit using a 14mm arm for massive rudder throw. Front servo is for Aerotow release!! |
Tuesday, 2 September 2014
Aresti 108 prototype
It's been a while, not only since the last time I made an entry but also for the Aresti 108 which I can now finally say has been born! It's at the Sloperacer workshops and busy getting it installed for it's first flight. The quality fit and finish for this huge, full carbon acrobat is definitely what you would call top notch 'EU quality'! Which shouldn't really be a surprise to us as our manufacturing partner is a renowned competition glider manufacturer in CZ. They have done a great job and all helps with the pride and excitement of seeing this project coming now nearing it's final stages. It definitely deserves the accolade of being a flagship model for us and this is only the prototype! It's designed by Dr James Hammond and though I'm obviously biased, dare I say it's his best to date! I and many others have always wondered what a Hammond design could do if it was built by a top EU manufacturer. Well we won't have long to find out!
The joiner is 40mm x 20mm in section and over 1/2m long! After all it's a huge plane, let's see if the following pictures do it justice.
The space for wing servos will allow full size 20mm thick all round but a bit of a squeeze in the aileron well so probably best with a midi 15-17mm servo.
The horn geometry and servo well positioning has been very well thought out and designed for flush covers
Well we know how the 2m Aresti flies and this big Aresti prototype has ticked all the boxes in terms of weight, strength and most importantly quality. It's exciting times, stand by for maiden report!
Even though it's a proto, it's beautifully made- simple stripe scheme for now but at least it isn't our usual 'white ghost' proto! |
It has some of the modifications from the 2m Aresti prototypes and so yes the rudder is enormous but then so is the whole plane, much bigger than you would expect for it's 108'' span. The pleasing thing though is that this prototype comes in at 2.7kg empty so reckoning on around 3.5kg ready to fly. To put this in perspective, I guess the X Models Stingray is a simlair size and aspect ratio. These are around 7kg empty! So we are really hoping for light wing performance too with the Aresti 108 someting I know a lot of acrobatic pilots have been asking for. However, there will be plenty of ballast provision with 20mm round tube in the wings and I'll be putting in 20mm tube in the fuse too. Aiming for around 2.4kg so approx 6kg fully laden. I'll guess we'll find out soon enough if this is going to be adequate!
Did I mention it's full carbon? That's all the tail surfaces too, only the front nose section is glass for 2.4 purposes.
Massive joiner! |
Yep, that's the chord! |
Can't wait to get this flown! It's going to be a show stopper on the slopes! |
Flap well about 25mm |
Aileron about 20mm |
Servo wells opened up on LHS wing, note they are angled to be at 90 degrees to the hinge line- no binding here! |
Subscribe to:
Posts (Atom)