Designing a docile, heavy lift canard

[meles meles]

'oomans, we are thinking of developing a canard platform to use for aerial photography but, being a small brained kreecher, we'd like some advice. Our thoughts centre on using two sets of off the shelf wings for the lifting surfaces - these are likely to be Easystar wings for the canards and Easy Glider wings for the main wings. Propulsion will be by one (or more) electric motors driving a rear mounted pusher propellor. Our desire is to create a long endurance platform with heavy lift capability and very docile flying characteristics. We have some questions:

1. Is it a good starting point ?

2. Should the canards and the main wings be at the same angle of incidence ?

3. Should the canards and main wing be at the same height on the fuselage, or should one set be displaced vertically relative to the other ?

4. Are there any rules governing the ideal separation (fore and aft) of the two sets of flying surfaces ?

5. Would we be better off using the aforementioned wings in a biplane configuration instead ?


Sits back, waits for the klever, big brained, 'oomans to respond...

[Sparky Paul]

'oomans, we are thinking of developing a canard platform to use for aerial photography but, being a small brained kreecher, we'd like some advice. Our thoughts centre on using two sets of off the shelf wings for the lifting surfaces - these are likely to be Easystar wings for the canards and Easy Glider wings for the main wings. Propulsion will be by one (or more) electric motors driving a rear mounted pusher propellor. Our desire is to create a long endurance platform with heavy lift capability and very docile flying characteristics. We have some questions:

1. Is it a good starting point ?
No.
Canards are odd ducks, with little practical application.

...
5. Would we be better off using the aforementioned wings in a biplane configuration instead ?
Yes.


Sits back, waits for the klever, big brained, 'oomans to respond...

[BMatthews]

Canards, by their very nature, cannot put the maximum lifting effort on the biggest wing. For heavy load handling or slower flying you're best off with a conventional layout.

The problem comes in due to stability requirements. For the rear wing to allow the front wing to maintain stability it can't operate at very high lift coefficients. This means you've hamstrung the main source of wing area into providing some lift and some stability instead of all lift.

[meles meles]

*Nods to the klever 'oomans, takes note*



So, if we want a slow flying, stable platform capable of carrying a camera, with very docile handling characteristics and, ideally, capable of STOL, what design should we be looking at ? We like the idea of using off the shelf components wherever possible so as to keep costs down and promote ease of repair...

Would for example, the Easy glider and Easy star wings in a biplane configuration be useful, perhaps mounted on a carbon spar fuselage ?

[Ollie]

It depends on the weight of the camera and about model sizes.

Think about a small, light, $15, film camera. Think about a Telemaster sizes or Sig Kadets sizes. Think about fuel weight rather than batteries weight. Think about balsa built up rather than solid foam. Think different!

Whole budget costs (price and effort). Think about priorities. You can get the cake but can't eat it too.

[Sparky Paul]

The Slow Stik gets a LOT of positive coverage in the Aerial Photography section here.
For the typical point-and-shoot digital camera of 4 to 6 oz., it appears to be infinitely modifyable and reliable.

[Ollie]

See:
http://www.zardec.net.au/keith/aerial.htm
http://www.walgreens.com/store/product.jsp?CATID=100380&navAction=jump&navCount=15&id=p
http://www.amazon.com/gp/product/B000069Z5H/104-8514254-2862365?v=glance&n=502394#moreAboutThisProduct

GWS Slow Stik, $40
plus
Pencam, 1.3 Mega, 1.6 oz. by Aiptek, $30

Cheaper than Easystar and Easy Glider plus camera.

[Thomas B]

One of the greatest lifting aircraft of all time happened to be a canard, but it was not a good flying or very stable aircraft based on all reports.

The Rutan Voyager around the world record aircraft flew at something like 450% of it's empty weight.....:)

I thnik you would be better off with a nice large stable conventional aircraft.....

[meles meles]

Thanks for the comments, 'oomans.

We happen to have a set of Easy Star and Easy Glider wings sitting around doing nothing at the moment (their respective fuselages are a little crumpled for flight though) hence the interest in reusing them. We did seriously consider a GWS Slo-Stick after reading the AP threads but haven't been able to locate one in stock at the moment in Great Britain.

Ideally we'd like to have something with the reported slow flying and easy handling capabilities of the Slo stick but with even greater lifting capacity. Any surplus lift capability over and above the camera weight may be used for a GPS unit and extra batteries to extend endurance.

We have a few more questions for you:

1. Why do the tips of the wings on the EasyGlider and Easy Star turn upwards ?

2. Most sailplanes have high aspect ratio wings, yet many high lift designs have shorter, low aspect ration wings. If both have equal area, what are their relative merits ?

[Sparky Paul]

There's polyhedral on those glider wings because they're rudder-controlled. The poly makes the plane roll into the turns.
The serious high lift planes go to the highest aspect ratios possible.
The wing is more efficient with high aspect ratio.

[meles meles]

*Hmmm, scratches ikkle 'ead*

The EasyGlider has ailerons for control, not just a rudder. We find it easier to fly than the EasyStar for exactly that reason.

What is it about the high aspect ration that makes the wing more efficient vis a vis a low aspect ratio wing of the same area?

[BMatthews]

.....The serious high lift planes go to the highest aspect ratios possible.
The wing is more efficient with high aspect ratio.

Up to a point this is true. But at our model sizes and speeds the Reynolds numbers become a factor. Sailplane designers have shown that there's an optimum minimum chord and that gains in speed range can be had by keeping this in mind. So the optimum aspect ratio for 2 meter gliders is 6:1 to 8:1 while the open class ships can get away with 10:1 to 12:1.

So a camera plane of 10 foot span by 4 inch chord would not really be that efficient.... not to mention it would be tough to build... :D

Silly ehlien, slow flight comes from low weight and lots of wing area.... or flying saucers that can divert gravity so they hover... :D

[mharms]

Silly ehlien, slow flight comes from low weight and lots of wing area.... or flying saucers that can divert gravity so they hover... :D

Got yer extraterrestrials and animals mixed up. He's a badger ("meles meles" = eurasian badger).

OMG! Maybe you're right -- he must be a "meles meles alpha centauri"!

[Sparky Paul]

10 foot span = 1 foot chord, at 10:1.
Eminently practical.
When tapered... 16 inch root, 8 inch tip, very good.

[meles meles]

Oh, we is definitely from erf, 'ooman. Well, under the erf anyway.

Being a small brained kreecher, we're still struggling to get to grips with why a high aspect ratio wing is more efficient than a low aspect ratio wing of the same area. We'd like to build a long endurance, slow flying, easy to fly, heavy lift platform. It seems that a canard is out of the running so now we're wondering what wing form to use.

[Sparky Paul]

Slow flying lifters.
http://www.angelfire.com/indie/aerostuff/sae2000n1.htm

[mharms]

Sparky,
Thanks for the interesting link.

Here's more SAE Aero Design East/West coverage (if you search a bit, you may find coverage for other years):

http://students.sae.org/competitions/aerodesign/west/2002pix.htm
http://students.sae.org/competitions/aerodesign/west/2004pix.htm

http://students.sae.org/competitions/aerodesign/east/results/2004pics.htm

Mark

[Sparky Paul]

I plumb forgot about the June event at Sepulveda. Drat!
Would have liked to see how they coped with the surrounding no-fly areas. :)

[BMatthews]

I'm not sure if "slow flying" and the weights those planes lift both go together....

I've got a 5.5 lb 84 inch old timer that just floats along. I use it as a powered glider more than anything. And at 5.5 lbs it's actually overbuilt with about 1/2 a pound of landing gear wire and a full on measured 1/2 lb of lead in the TAIL to get it to balance. With the big polywog airfoil and all the wing area it definetly qualifies as a slow flier and is very beginner friendly being easy to fly with polyhedral wings. A purpose designed and built plane could easily be built that weigh 4.5 lbs with the same wing area and overall planform and fly under power in an easy outdoor slow manner at an AUW of 6 lbs (and probaly still catch thermals with the engine off if you wanted to and know how). Part of the secret is the light weight and large wing area and added to that is the fairly thick and highly undercambered airfoil which is a Gotinggen 497.

The biggest factor in keeping such a model light is to build in a lot of air in the model. Silly it may sound but by building the model with lots of sticks and open structure and using a fairly light covering material you can easily do this. Things that add weight are lots of sheet balsa and plywood along with a liberal use of heavy music wire.... I don't even want to talk about fiberglass unless it's thin and vacuum bagged to control the amount of heavy resin.

[meles meles]

Interesting links, 'oomans.

Can anyone direct us to a source of information on aerofoil shapes and basic aerodynamics - we're determined to get to the bottom of high aspect versus low aspect ratio wings ? Our thought was that if they were the same area they would generate equal lift, but a short fat wing would be less susceptible to gusts and turbulence than a long thin one...

[Sparky Paul]

Short wings are less susceptible to turbulence.
Long wings are more easily seen at a distance.
Short wings have more "induced" drag.
But..
Short is probably best defined as an AR < 6.
Harder to fly.. wings level.
For AP, ridiculously easy to fly is the goal.
The purpose is to obtain the photograph, not demonstrate any particular airplane design.
.
Thick is relative.
Highly cambered surfaces can appear thin, but are actually thick, when observing the drag polars.

[meles meles]

Yes, we like the sound of ridiculously easy, though we only plan to use it for AP, not dragging polar bears around. That sounds a touch risky.

So, do we go for a high aspect ratio glider style platform, like the U2, or a lower aspect ratio wing like that used on the Canberra ? Maybe a biplane using short thick wings?

[Sparky Paul]

I use the wing from the Gentle Lady, or the GP Spirit... both AR, and strong, and ridiculously easy to fly.
Shorter span wings work, but I prefer the longer guys.. the plane stays in sight longer.

[BMatthews]

There's this little thing called Reynolds numbers that comes into this. You ehliens probably don't know him if you just arrived but he set up a mathmatical relationship to describe how smaller and slower things see air and airflow differently from big things or faster moving things. This comes into play with airfoils. Really short chords flying at slow speeds see the air differently than longer chords flying faster.

So this is why truly high apect ratios in models only work with larger models where the chord is wide enough to provide a higher (and therefore more efficient) reynolds number value.

You can make something with a 3 inch wide chord fly well but it needs to be stupidly light even if it has a 50 inch span. But a 30 x 5 inch wing may well lift better even though it has a far smaller span and therefore more induced drag just because the airfoil is able to operate in a more efficient manner due to it's chord and how the air treats it.

If I could speak ehlien I could describe this in a more technical manner that you'd understand.... :D Actually if you look at lift drag polar (bears) with multiple curves at different reynolds numbers you'll see how the lower number curves produce more drag and often have terrible looking performance curves. This is a result of this "scale" factor of how the air flows over things.

[meles meles]

So, 'ooman, what you are saying is that a short, thick wing is probably best ? We like short and thick, it's rather like us. We is furry though, not scaley. Scaley is for dragons. And we isn't an ehlien...


*scurries away to draft up a plan for a low aspect ratio, high area wing. Wonders what airfoil section to use... and if any of you 'oomans would recommend the book "Basics of Model Aircraft Design" by Andy Lennon*

[Sparky Paul]

Here's 18 uv'um
And the optimum, as far as I'm concerned.
Short, thick,would be a Kadet. AR of 5
Better performance, a 2M wing on a fuselage. AR 8+

[meles meles]

Hmmm, the ikkle twin boom aircraft looks nice. Wouldn't it be better with:

1. a pusher prop though so as to minimise the chances of damage in a rough landing ?
2. separate verticaland horizontal tail surfaces ?


We've also just read the following advice about the ideal characteristics for a trainer on a separate thread, which seems quite sensible to us.

High Wing - A high wing model is inherently more stable than a low wing model due to pendulum effect. Since the weight of the model is below the wing, the fuselage tends to swing downward like a pendulum in order to equalize forces.

Flat Bottom Wing - The wing cross section should have a virtually flat bottom. This type of cross section has more gentle flight characteristics that are necessary for a beginner.

Dihedral - The wing should have some dihedral. This means that the tips of the wings are higher than the center. The effect of the dihedral is to try to equalize forces and keep the wings level or to return the wings to a level orientation

High Aspect Ratio - The ratio of the wing length or span should be at least 5 1/2 times the width or chord. This will reduce the rate at which the model responds to command input allowing more time for a beginner to react.

Constant Chord - The width of the wing should be the same from the center or root to the end or tip. This distributes the weight of the airplane evenly over the entire surface of the wing.

Low Wing Loading - The weight of the model divided by the area of the wing should not exceed 19 oz./sq. ft. This reduces the speed required to maintain an acceptable rate that the model descends when the power is reduced resulting in a lower landing speed.

Moderate Size - Most trainers are for engine sizes between .15 and .60. The smaller ones are more susceptible to the effects of wind and normally the wing loading is higher simply because of the weight of the radio equipment. The larger sizes are easier to fly and easier to see but are more difficult to transport. Most trainers are for .40 size engines. These trainers have been widely accepted as the optimum size.

[Sparky Paul]

Replace all the places with "should" with "can be".
Pusher motors move the c.g. back, which makes the nose long to move it forward.
And places the camera up front when the landing event occurs.
Vee-tails are easiest to set up.

[ToddF]

Meles,
I found this thread late in the game. I started on a long winded reply yesterday, but lost it in a computer lock-up. I'll be briefer this time.

Getting back to your original question about canards, I've built and flown three canard planes from existing wings. Two of these I've used for AP. You can see these on my website: http://members.cox.net/todd-f/RCplanes/RCPlanes.htm

Canards have two plusses for AP: 1) They tend to be pushers, so the prop is not in the field of view of a forward looking camera. You want the camera to be forward looking to minimize motion blur. 2) The CG of a canard plane is back near the leading edge of the main wing. This normally means that the camera is pretty well protected in a nose-in crash.

There is one big minus. A canard plane needs to be landed with a bit of speed to prevent nose-ins. For stability, in a conventional plane the main wing stalls before the tail. This ensures that the nose drops, airspeed goes up, lift returns and recovery occurs. In a canard plane, the canard stalls before the main wing for the same reason. In a conventional plane, with the main wing in stall, you still maintain pitch control with the elevator in the tail. In a canard plane, if the canard stalls, you loose pitch control.

When flying AP missions, your landing sites are usually not optimal. There usually isn't room for long takeoffs and landings. For this reason, and also to protect the camera, you want to land as slowly as possible. In the canard planes I built, I would end up stalling the canard when slowing to land. If this happened a couple feet from the ground, there was usually no problem. But, I had enough nose-ins from head height to make me want to either redesign the canard, or to switch to a more conventional layout.

I've decided that my next AP plane will be a conventional winged, twin boomed pusher, much like the one in the right hand picture in Paul's post. The pusher gets the prop behind the camera, and the long nose provides a measure of protection for the camera.

I still have no regrets about starting with a canard plane for AP. I built the first canard plane just to see if I could. Even if I don't use it for AP anymore, my canard plane will remain one of my favorites just because it is cool. Designing and building one from scratch will teach you a lot about aerodynamics because you really have to think about how it works to get it tuned properly. If you want to build one, do it because you want to try something new. When you get it flying nicely, mount a light digital camera at the CG and snap away.
Todd F.


'oomans, we are thinking of developing a canard platform to use for aerial photography but, being a small brained kreecher, we'd like some advice. Our thoughts centre on using two sets of off the shelf wings for the lifting surfaces - these are likely to be Easystar wings for the canards and Easy Glider wings for the main wings. Propulsion will be by one (or more) electric motors driving a rear mounted pusher propellor. Our desire is to create a long endurance platform with heavy lift capability and very docile flying characteristics. We have some questions:

1. Is it a good starting point ?

2. Should the canards and the main wings be at the same angle of incidence ?

3. Should the canards and main wing be at the same height on the fuselage, or should one set be displaced vertically relative to the other ?

4. Are there any rules governing the ideal separation (fore and aft) of the two sets of flying surfaces ?

5. Would we be better off using the aforementioned wings in a biplane configuration instead ?


Sits back, waits for the klever, big brained, 'oomans to respond...

[meles meles]

Hmmm, that looks like a good ikkle plane - though we notes that you you eventually went for a twin boom pusher in the end. That's probably what we'll end up with, unless we can qualify for some Arms Aid from Uncle Sam in the form of a squadron of Ravens...

[Ollie]

"That's probably what we'll end up with, unless we can qualify for some Arms Aid from Uncle Sam in the form of a squadron of Ravens..."

For Ravens ($15) see the Uncle Sam (RCM):
http://www.rcmmagazine.com/e/env/00016vOMdDS0lPMrMQ4B3B3/store/store-plans-list-5.html?link=/store/store-plans-catalog-tem.html&item=plans:pl-1160

[BMatthews]

Hey, you... yeah, you in the fuzzy suit. Sorry about the ehlien stuff and making jokes about you double parking your spaceship. It's just that you look a little like an Ewok....

We 'oomans have a little story about a girl that breaks into a house belonging to a family of bears and eats their porridge that they went out to get milk or raisins for or somethin' like that. And like the baby bear's porridge (that evil girl eh? Taking food from babies!) that was "just right" aspect ratios are the same. You want a narrow chord and long span enough to gain SOME of the advantages of the lower induced drag of the higher aspect ratios but not so high that the chord becomes too narrow. The Soartech volume whatever on this topic pretty much learned that 7 to 8 inches is the minimum chord that will ensure a decently efficient airflow over the airfoil. So oddly enough we come back to Paul's (that clever'er'er 'ooman) Gentle Lady wing planform.

If you want to fly REALLY slow at the expense of not being able to handle much wind, or at least not let it fly downwind on breezier days, then you will want an airfoil with a higher camber. For you that pretty much means something of moderate thickness and with at least SOME undercamber to complicate the covering job. But if you go for something like that you'll be rewarded with some truly slow loiter and very tight turning ability on the calm to light wind days.

[meles meles]

These bears wouldn't be the polar bears that lift the wings up would they ?

So, it seems that we are refining our choices towards:

1. A twin boom design
2. Pusher prop
3. Wings with dihedral
4. About 6 :1 aspect ratio
5. Around 8 inch chord or more
6. Flat wing underside

Which ought to give us a decent compromise of lifting ability, docile flying, slow speed and a little breeze tolerance?

[Sparky Paul]

Wing structure.
Don't use open structure.
Sheeted leading edges and shear webs.
This was an Oly II... with two Aiptek cameras in the nose. Both smashed to itty-bitty parts when the wing fluttered.

[BMatthews]

They are close cousins from across the river.

7. And a careful eye on the grams scale at all times. Lighter is always Righter.
8. Use a true ClarkY if you want to stick with a good performer that is easy to build and cover. But if you don't mind some undercamber covering then I can heartily recomend the Goetingen 497 as a good option that will lift decent loads while still flying slowly and yet has a reasonable degree of wind penetration.

If you are up to the building task and time I would really suggest a nice stick build. Think of it this way. For example, a square box using 1/4 square corner longerons and 1/8x1/4 uprights puts the vast majority of the wood out at the corners where it can do the most good. Compare the wood volume in such a structure to a sheet box made from 1/8 sheet for sides and formers with a 3/32 top and bottom. If you do the math you'll find that the built up version uses about 1/8 or even LESS of the volume of wood for something with as big a fuselage as a camera plane requires.

I find that it's best to make the model so that it can balance WITHOUT the camera or other load in it. Otherwise as the loads change you need to play with ballast to keep the CG in the same spot. if you're going to do this with electric motors I'd say make the twin booms extend forward and use TWO electric motors and add the cargo pod in such a way and with such a design that the load is located at around the leading edge of the wing or even back a bit between the leading edge and the CG. That'll make for far less CG issues later on.

A nice lightweight way to make the tail booms would be to roll 1/16 sheet or 3/32 sheet around a long tapered or constant diameter form. Yes I know I was all about sticks and boxes earlier but a tube has advantages as well for a reasonably small weight penalty. But built up booms would look sweet covered in clear covering. What you want for a built up boom would be a Warren Truss structure. Look at a built up crane boom for an example of this form of structure. The side frame diagonals in a WT need to be mirrored so that the top and bottom diagonals all match up but what you end up with is a very strong and very light structure for the amount of wood used. Use very hard wood for the longerons and medium for the diagonals.

[Thomas B]

A pool cue makes a nice tapered form for rolling tapered balsa tubes...

[meles meles]

*hides porridge*


One design we thinked of earlier, dismissed, but may now resurrect is what we call our EasyP38. It is essentially two EasyGlider Electric fuselages used as the booms in a P38 Lightning style arrangement with the camera mounted in a pod between the two booms. The pod would be made from carved EPP foam coated with a fibreglass skin. We could either keep the two standard EasyGlider Electric 'lekky motors in the noses of the booms, as per P38, or replace them with a single, larger 'lekky motor used as a pusher and mounted on the back of the payload pod.

The payload pod would be joined to the two fuselage booms by a low aspect ratio wing for plenty of surface area (the pod itself would be a lifting body shape) and the wings outboard of the booms would be standard EasyGlider parts...

*waits for klever 'oomans to comment, tries not to look too ehlien...*

[BMatthews]

Now you're cooking with gas! Run and turn it off quick before it boils somethin' over!

The pod will have a low enough "aspect ratio" that an airfoil shape will only help cut down the drag. No useful lift will be generated. Or did you already see that in the fortune cast by the porridge dregs in the bottom of the bowl?

As a quick build trick the idea of two skinny glider fuselages is a great one. I personally like the ideal of the two 'lekky motors since it helps put the CG where it needs to be without needing to shift the payload around. A single pusher motor likely will need a VERY long nose or some way to locate the payload and flight gear to put the CG in the right spot.

Now mind you..... commercial gliders are intended for beginners and odd looking bears to train on so they are stronger and heavier to survive crashes. If you're serious about slow flying then you want to shoot for a lighter overall weight. It's more building but with a bit of care (and those bear like reflexes to keep the model out of trouble) there's no reason you can't have this model for many years. I've got gliders and old timers that are over 20 years old and can well last another 20 since they don't do more than very gentle aerobatics.

... oh, and by the way, if you're trying to blend in then you should make your eyes stop glowing like that..... or is that just the glimmer of an idea?

[meles meles]

Badgers isn't bears, we is mustelids are us. Like weasels and stoats, but bigger and better.


Weight and CoG considerations aside, we liked the idea of a singlepusher prop for two reasons:

1.To keep the prop blades protected when we nose dives into the ground
2. To try and reduce control problems arising from asymmetric thrust should one engine fail.


Problem 2 - asymmectric thrust - we can presumably minimise by using 'lekky motors running in parallel from a common battery. Either both will work, or neither will work.

The pod may well be made from Hexcel, two thin skins of glass over an aluminium (aloominum to you 'merrykans) honeycomb. Quite a strong structure and reasonably light. (The polar bears could lift it easily). The central wing will have bags of surface area, maybe flaps too if we can manage it.

[Sparky Paul]

Twin electrics... both motors can be shut off at the same time.
No biggie if they aren't.

[BMatthews]

I knew a weasel a few years back but he sold used cars of questionable quality. Or perhaps that's not quite the same thing?

If you doubt your abliity to fly well with the paws on the sticks then perhaps it's time to make something easier to fly and get to the point that you don't need to worry about the props.

Besides with something that looks vaguely like a Fairchild Packet the pod nose will hit long before the props if the props are up on the wing and the pod is slung under the wing and has the landing gear on it.

http://www.ruudleeuw.com/c119-ethiopia.jpg

[meles meles]

*Is impressed, and wonders if there is any type of plane the Sparky type 'ooman hasn't made*

We think the Pakkit is very similar to what we have in mind, though we'll be hoping for something a little closer to the P38 in styling, ie with a smaller, sportier looking centre pod... As for flying skills,we frequents the UAV forum here quite regularly: we rather like the idea of being able to programme the desired route at leisure rather than having frantically to waddle the ikkle joystiks about with our paws as the 'plane plummets towards Chikkin' Little...

[BMatthews]

But then you miss out on all the FUN! ! ! !

Truly with free flight style design and stability and reduced size control surfaces there's no reason you can't just ease the model around the sky. If the UAV folks would just use the rich history of unguided model free flight design as inspiration we could put the gyro companies out of business. Long before there was radio there was free flight and the models flew just fine without any help at all. Time to dwell on that over your next hibernation period, eh what?

And of course the pod size will be determined by the size of the payload.

The model in this pic is radio guided but it's originally a 1939 free flight model. One day I put it up side by side with a buddies pure free flight gas powered model of similar size and weight. The deal was we both go "free" at the same height and see who wins. Well, as it turns out mine caught a very weak thermal and his got pushed out by the same thermal. But mine wasn't really centered as near as I could tell so I started trying to use the radio to "help" it. Every time I touched the sticks it messed things up. Finally I let it alone and it came down, went up, came down,went up, etc until it was a spec. It was a super weak thermal but the model knew just exactly what to do with it and centered itself better than I could. Yes it was a humbling but valuable lesson.

Mine is the red one in the front and my buddy's is the white one in the back.

[meles meles]

Hmmm, 'em is sure purty ikkle aeroplanes 'ooman...

We thinks we will still contemplate a UAV system - flying aeroplanes by remote control isn't easy when you 'as big paws and a small brain.