Solar blimp/Aerobatic airplane

[only1jake]

Hi, found some articles which I thought some of you guys will probably be interested in:

Solar Blimp Preps for channel crossing:

http://www.wired.com/autopia/2010/06/projet-solr-solar-blimp/

Aerobatic Airplane Has Four Electric Engines

http://www.wired.com/autopia/2010/06/airbus-parent-company-unveils-four-engine-electric-plane/

Interesting!!

[Jeremy Harris]

Hey! An electric CriCri!

An acquaintance of mine has one of these, he keeps it at the airfield just up the road from me, but his still has the original chainsaw engines. I'd never thought of it as a candidate for electric power, but as it is aerobatic on two direct drive chainsaw engines it makes perfect sense to just fit some big outrunners on it.

Jeremy

[AussieJester]

Hey! An electric CriCri!

Good lord Jeremy, they look smaller than some of the scale rc aircraft i have seen at the flying field in the past LoL. Looking at the wing area i would suggest it glides like a brick when it loses power?
Either way wouldn't get me in either aircraft even on the ground as im shit scared of flying haha..

KiM

[Jeremy Harris]

Its pretty small, AJ. I'm used to flying in some weird and wonderful flying machines (see below for a few) but even I'd think twice about flying a CriCri. It does look just like a big model aircraft and has some interesting construction features, like alloy skinned wings that are glued to foam ribs.............


Me flying over a mate on the ground who decided to take an arty photo.....



Same microlight as above, just after I'd landed


Skimming across the sea, about 6ft above the waves, just for the sheer hell of it..........


Stopping for a coffee at a marina in the Algarve, Portugal. It caused a bit of a stir when I landed this float plane in the harbour at Alvor. I got stopped by the harbour police as I water taxied out to fly back to Lagos, but they didn't speak English.........


Approaching the white cliffs of Dover on the way back from a memorable trip to France in a flexwing microlight. Its my favourite flying photo, as it was a weekend when about 120 of us flew across to France from England and down to a small airfield near the Somme, Abbeville, to celebrate the centenary of powered flight. Much partying was done along with a fair bit of drinking, before we all flew home on the Sunday.


Finally, a shot of my current flying machine. I'd love an electric paramotor, just to get rid of the 120cc two stroke that's screaming away behind my back.

Jeremy

[AussieJester]

Your MAD Jeremy hahaa... i get the jitters just looking at Ultra lights, they look like the
wings are about to fold up ... The famous white cliffs of Dover...nice shot mate
I think i will be keeping my feets/wheels firmly planted on terra firma though
unless of course i get rich and can buy a helicopter and flyz it myself
then i think i would be ok with the whole up in the air thing, long as i am in control, i also make
terrible passenger in a car hahaha..

Thanks for the pics Jeremy great to see your other 'hobby'

KiM

[Tiberius]

More on the Cri-Cri, and to get it in scale, here is a picture of one with its owner, Ken Rhodes.

He parks it under his other plane.

Nick

[AussieJester]

I'd be pulling out the DX7 Spextrum transmitter and fitting servos to that to fly it

KiM

[pwbset]

Hey Jeremy.. I'm a paraglider and am curious what glider you're using for your PPG setup in that photo? I'm contemplating a windtech kinetik plus with electric rig someday as I've flown and love Windtech gliders before. Also flown Skywalk, Gin, Advance and Up, but keep coming back to Windtech for their "feel".

[Jeremy Harris]

Off the top of my head I think it was my old Trekking Parawing, but I can't be sure - it was around three years ago. The motor is a borrowed RAD, but my current motor is an H&E R120. I built a trike for the H&E motor, as my ankles aren't really up to foot launching now. This is what it looks like:



Most people over here are flying reflex wings on paramotors now, mainly to get a bit better speed. I borrowed a Revolution reflex wing, which is pretty old hat now, but was impressed with the way it just popped up, nice and stable, on launch and cruised at maybe 5mph faster than my non-reflex wing. I've not kept up with the latest wing tweaks, but suspect they've got even faster over the past couple of years.

I'd like to have a go at building an electric paramotor one day, once I've got around to finishing some of the other projects.............

Jeremy

[pwbset]

my ankles aren't really up to foot launching now

I hear that... got flushed from a thermal in '05 climbing off launch, fell about 150ft and snapped some tendons and sheared my talus bone (despite my Hanwag boots, which probably saved my foot overall). Never did get the tendons fixed/replaced... doctor said it was "optional" and that I'd just have a "floppy" foot. Still ski/hike etc. so it hasn't slowed me down... much. Saving up for a new paraglider at the moment and plan on flying a bunch summer of '11.

Sweet trike by the way!!!!

Safe journeys to you.

[bluthermal]

Jeremy,

Nice simple and clean trike design for your paramotor. What are the materials and/or construction details of the cross-member for the rear (landing) wheels?

I was guessing/speculating that the Green Cri-Cri might be using 4 Plettenberg Predators for the motors.

[Jeremy Harris]

Jeremy,

Nice simple and clean trike design for your paramotor. What are the materials and/or construction details of the cross-member for the rear (landing) wheels?

I was guessing/speculating that the Green Cri-Cri might be using 4 Plettenberg Predators for the motors.

Thanks for the kind words. The trike is all composite. The square tube is 2" square Fibreforce pultruded fibreglass and the semi-elliptical rear spring is made from carbon fibre, with a balsa core. I made a conventional mould for the top surface of the spring, laid up a mix of unidirectional carbon tape and bidirectional glass, then added a balsa core, before finishing off the underside with more layers of carbon and glass. The balsa core is smaller than the width of the spring, so the underside layup wraps over the core and is bonded back to the upper and side surface of the top layup. Here's a sketch showing a cross-section through the layup:



And here's another picture showing the raw spring bonded to the composite trike. The trike comes apart to go in the car - there's a sliding joint held together with a pin:



Jeremy

[bluthermal]

Wow Jeremy,

It's crystal clear you but a lot of care, thought, effort and skill into your trike build. It really shows, excellent job!

So, the "T" joint (connecting the rear spring to the front wheel longeron) is composite too? How does the joint of the "T" get it's strength?

[Jeremy Harris]

Wow Jeremy,

It's crystal clear you but a lot of care, thought, effort and skill into your trike build. It really shows, excellent job!

So, the "T" joint (connecting the rear spring to the front wheel longeron) is composite too? How does the joint of the "T" get it's strength?

Thanks again.

The T joint has an internal bit of 1 3/4" square pultruded box section bonded inside it. I cut a 1 3/4" square hole on the front face of the bit of 2" square tube that's bonded to the top of the spring, so I've created a T joint that's a bit like a tenon joint, but in composite. The 1 3/4" box extends forwards right through the 2" box that joins to the front of the T and forms an insert for the sliding joint that holds the front of the trike to the rear section.

Jeremy

[bluthermal]

Jeremy,

Thanks for the informative replies. I don't mean to bug you, but, exactly how did you reinforce the angle behind the front fork? I'm really intrigued by your build technique. I've used a similar telescoping type square steel tubing for lots of my car rack projects in the past. Is there something I need to know about the front forks too?

Mark

[Jeremy Harris]

The bend in the main box section was made by making an angled internal stiffener section that is bonded inside to hold two bits of box together. I made a split female mould, using a bit of 1 3/4" box as a buck, then cut the mould at the right angle and glued it back together again. I then laid up a mix of unidirectional carbon fibre and biaxial glass cloth in this mould, finishing by bonding the left and right moulded parts together. I ended up with a short section of 1 3/4" moulded box section with a bend in it that I then just bonded inside the 2" box pultruded sections at the joint.

I still have the mould somewhere, I'll try and dig it out and take a photo so you can see how I did it.

Jeremy

[liveforphysics]

More on the Cri-Cri, and to get it in scale, here is a picture of one with its owner, Ken Rhodes.



Nick

WOW! Now I know what plane I want! I'm pretty certain I've seen a few RC planes at my local airfield with more wing area, but they don't have a spot to sit in them!
Would they work with a 95-100kg pilot?


Looks like they've got plenty of power to be safe, and seem to fly great! That guy is flying pretty much like normal medium-power RC plane flying, but your own hands get to be the servos, and you get a hell of a lot better view.

[Mike B]

Electric Cri-Cri flew today..WOW

"WAPA) - The all electric Cri-Cri, jointly developed by EADS Innovation Works, Aero Composites Saintonge and the Green Cri-Cri Association has made its official maiden flight at Le Bourget airport near Paris on Thursday. This Cri-Cri is the first-ever four-engined allelectric aerobatic plane, which was first shown at the "Green Aviation Show" at Le Bourget in June. "

http://www.avionews.com/index.php?corpo ... =index.php

(edit) http://www.flightglobal.com/blogs/as-th ... earth.html

[Doctorbass]

The Cricri might actually use the Predator 12kW Rc motor and controller!!

http://www.jp-petit.org/nouv_f/avion_electrique/avion_electrique.htm




and...

Powered by a four-pack of lithium-polymer batteries pumping a total of 400V, the Green Cri can perform 30 minutes of cruise flight at 65 mph, crank it up for 15 minutes of intense aerobatics at 155 mph and climb the skies at a rate of around 17 feet per second. Majority of the parts have been made from lightweight carbon composite material, keeping the weight low, despite the extra weight put on by the 59-lb battery array.



They operate at 400V!!!

or maybe i would hope it's 4 x 100V battery

Doc

Doc

[fizzit]

What is that blue thing?

It looks suspiciously like the 450v 2,300uf cap I have in my coilgun

[only1jake]

Looks like it. Make a thread on your coil gun

[dodjob]

french:
"le système qui convertit le courant continu délivré par les batteries en "courant alternatif", triphasé" ( en fait sous forme d'impulsions )"
English:
"Brushless controller"
By the way, Damn Plettenberg motors! I would be really interested to know the efficiency at 400V... it's quite crazy, I would think that the core losses should be really big!

Gruß,
H.

[grindz145]

Jeremy,

You are even more my hero now, if that was possible...

[Gordo]

More on the Cri-Cri, and to get it in scale, here is a picture of one with its owner, Ken Rhodes.



Nick

WOW! Now I know what plane I want! I'm pretty certain I've seen a few RC planes at my local airfield with more wing area, but they don't have a spot to sit in them!
Would they work with a 95-100kg pilot?

Looks like they've got plenty of power to be safe, and seem to fly great! That guy is flying pretty much like normal medium-power RC plane flying, but your own hands get to be the servos, and you get a hell of a lot better view.

Luke;
I should not tempt you, but there is a Cri-Cri sitting here for the past 10 years. The owner is @ 78 and still flies many other aircraft. It is just taking up space in his garage at home. I'm not sure of the gross weight, but they don't seem large enough for any more than a hoptoad to me.

[AussieJester]

Jermey or anyone else that knows i guess..is the CriCri classified as an 'ultra light' or is it a full fledged aircraft you need a pilots license to fly?

KiM