Cliffwhacker

[Leslie Crane 1]

hi Busterprop I did add elevator to flap flap set at 120% elev 18% it seems ok to me Les

[buster prop]

Thanks Leslie, I'll bear those figures in mind.

[Leslie Crane 1]

Pat, the dive test you sent me is working well. I have already removed lead from the nose on 2 occasions and the model flies better. It still needs a bit more removing which should give the correct dive profile. It is steadier and I am managing rolls although they take up a lot of vertical sky but a definite improvement. Les

[PatMc]

Good to know, Leslie.
I hadn't realised quite how small the ailerons were until I had a better look at some of the photos in this thread. IMO they would have been more effective with a wider chord or full span, personally I doubt if the flaps are worth the bother.

[Leslie Crane 1]

Pat you are right, I have landed with full flap and just as well with much less and have no doubt that with none at all it should be fine. As I have each aileron on a separate channel on the Rx I could just Y lead the flaps with the ailerons on each side which will give me the equivalent of full span ailerons. I can then see what difference it makes to the rolls and turns. Les

[Eddy Scholte]

Hi, my name is Eddy and today I have had the maiden flight. My English is not very good, but hopefully good enough for you. I do apologize for that. (I know, 9 years in the UK and still struggling)

Don't know if this is okay. First time I try to post a picture. Second picture looks a bit strange with the colours)

Today the maiden flight at Butts lane in Eastbourne. I was very surprised how well it was flying for the first time. Bit of trim required for Elevator and right Aileron. Very good lift. Few birds where following the glider, but didn't go for an attack. Landing was not brilliant, but that is more my inexperience with flying. No damage at al. I have tried to land with the flaps but not a success because the flaps were mixed with a bit of up elevator. Not a good plan. Next time better. (any advise?)

Happy me.

[Leslie Crane 1]

Hi Eddy your English is fine. Flaps cause the nose to rise generally so down elevator is called for. On my C/whacker 1 degree of elevator for every 10 of flap works - a good starting point for you. Let me know how you get on with rolls and loops as mine is not very good. Your model looks very nice. Try looking at Sussex Slope Soaring site if you want company when flying they are a good crowd and fly from various sites from Mill Hill at Shoreham to Ditchling, Firle Beacon, Bo Peep, Newhaven Cliffs and Beachy Head. All within easy distance of you. Les

[buster prop]

Well, I finally maidened my Cliffwhacker this morning. Slower than my Sierra 2 but easy to fly and manoeuvrable, just needed a bit of trimming. The flaps didn't seem very effective but weren't needed really as the CW can be slowed for landing without them. I have some up aileron mixed with full down flap, and elevator compensation, programming this was a learning exercise for me with my new DX7. I have about 25% aileron to rudder coupling which seemed about right. I think the comment about the ailerons being small is spot on, I tried to get it to roll but even on high rates it seemed slow. I may do away with the flaps and just have full span ailerons as Eddy did. Like his colour scheme btw. I'm glad I built it, can't have too many slope soarers!

[Eddy Scholte]

Hi Leslie, thanks for your comments, very useful. I will give it a go and let you know when I have some sort of result with a bit of down elevator. I have a DX7s transmitter and have been struggling with the settings. Wanted to fly with a 4 servo wing, but 1 of the flap servo's was much slower. So ended up with a Y-cable and then they had the same speed. But I don't know why that happened. But for now I am happy with it. I am already a member of the ESSA (East Sussex Soaring Association),

Hi Buster, that is what I like to do also, a bit of up aileron mixing with full flaps. Do you use the throttle for that? I use the 3 position switch for the flaps, but maybe have to change that also. Btw...........I don't have full span ailerons. Just flaps and ailerons. But maybe there is be a possibility to mix that?

Eddy

[buster prop]

Hi Eddie. I put the flap servos on a Y lead plugged into the throttle channel of the receiver and launch with the throttle stick fully forward and flaps up. I did a mix which makes the ailerons go up at more than half flap to get a crow braking effect. Full flap almost makes it stop and I'm pushing in down elevator to keep it flying. I have flown the Cliffwhacker again and conclude that the lack of roll response is just because the model is slower than my other slope gliders like the Sierra 2. I may try adding ballast.

[Leslie Crane 1]

Hi guys I added the ballast and whilst it made the flying smoother with a little extra speed - and I intend to keep the ballast for all future flying - it did little to help the roll rate. I am convinced that it is the small ailerons which are the problem. I wonder what they did on its maiden for the magazine to be able to say it rolled so well. I didn't see it roll in the video - or did I miss that?!

[Two Six]

I am thinking about building the Cliffwhacker or the Ballerina. Not sure which one to do first at this stage but I have most of the wood to get cracking with the CliffWhacker..I might make it electric.

The thing is I have "lost " the original magazine with the build instructions in it. In fact I remember giving it to my dentist's surgery for their waiting room. Doh!

Any chance somebody could scan and email me the original article?

Or post some build instructions on here?

Thanks!

[Pete Crosby]

Well Very late start by looking at the last post, so I thought I resurrect the thread by adding my newly started CliffWacker, got bored waiting for wind to drop so raided the scrap box and a few sheets to build an oldish plan i have.

building on my Magnetic jig so Its nice and true, wing ribs cut ready for final shape, fuse jigged and growing

 

 

Edited By Pete Crosby on 01/05/2017 12:12:10

Edited By Pete Crosby on 01/05/2017 12:12:34

[Andy G.]

Pete, don't worry about being late, I started this thread but still haven't started to build a Cliffwhacker!!!!!! LOL

[Pete Crosby]

[Dane Crosby]

Hi All,

I have finished my Cliffwhacker and have made minor mods to the plan.

Due to the gusty buffeting winds here in North Cornwall I sheeted the entire wing

I made thick section winglets from builders foam covered in glass tissue and Poly C

It is designed as a power assisted glider, not a hotliner. It has a tiny 6x4 folder prop powered by a 2200kv motor which has 60 seconds max at 220w and 180w continuous on 3c 1800 or 2200.

Three flight modes, normal, thermal (variable camber) and crow.

Just lovely to fly, thank you mr Whitaker.

[Dane Crosby]

Forgot to say that it has an eight channel DSMX system with full telemetry too.

[Tomas Dunker]

Earlier in the thread it says:
a wood completion set is available from the Plans Service.
But I can not find where I can order this?

[Two Six]

Nice build Dane, I hope I can do such a good job with mine!

I really like the winglets, do you think they make a difference to its gliding performance or stalling behaviour or are they just there to look nice?

I have just got back to building mine, some rubbish things happened early in the spring round here and my build project got totally de-railed, I was hoping to get it done by early summer.

I will be having a go at a wing today in fact. I have a build blog here : http://www.multi-rotor.co.uk/index.php?topic=20650.0 I will update it soon.

The wood kit is here: http://www.slecuk.com/cgi-bin/sh000001.pl?WD=highside&PN=Highside%2dGlider%2dCNC%2dPack%2dPRC001%2ehtml#SID=248

I think I am going to build mine as a glider to save weight, complexity and cost. I have other powered aircraft I can fly to test out lift with before I fly a pure glider.

When I bought the SLEC kit, they "forgot" to put in aileron strips, they said they would correct the oversight but watch out for that and check they have included two aileron strips in the kit.

Apart from that the parts kit has been fine so far and as a noob I have managed to do a reasonably good job with it.

 

Good luck with your build!

 

Edited By Two Six on 05/11/2017 10:37:11

[Tomas Dunker]

The above link is not for Cliffwhacker wood kit?

[Two Six]

Oops!, so sorry. Build the highside instead?

 

I thought that Highside looked a bit strange.

 

Edited By Two Six on 05/11/2017 16:15:41

[Dane Crosby]

Hi 2,6.

I didn't like the very basic finish of the plan wing tips so I designed ones to control tip vortices and make it look pretty. I have never been good at stretching iron on coverings around delicate wing tips. I can always make wrinkles !

It is nice and stable in the gusty winds here but may be it is stable with the plan wing tips, I don't know.

[buster prop]

It doesn’t seem like 3 ½ years since I built my Cliffwhacker which now has full span ailerons instead of ailerons with flaps. Today there was a moderate breeze onto the slope and I threw the Cliffwhacker off and found I was having to hold in some elevator until I got some up trim in. When I landed it the elevator neutral was slightly up. With 63g of lead taken out of the nose and the elevator trim back to where it was the model flew better, going faster with more penetration and the elevator level which has to be better. It goes up fast in lift and I only had to give a nudge of down elevator to level it off. The model feels stable and no tail dragging in turns, although the balance point is now about 1cm behind the spar rather than on it as it was before. My next flight was over 20 minutes and after a sandwich and chat break, one or two more. I went home feeling pleased with the Cliffwhacker. Are the other models in the 2015 thread still in existence? A glider I would recommend and well worth the building effort.

[Dane Crosby]

Hi BP

My Cliffwhacker is still flying. I found that 180w - 200 w was not enough for a fast climb to height.

I replaced the motor with one of over 400w. A vertical climb was the result which was fun for a while.

Six weeks ago I made another hand launch to be surprised by the motor and firewall departing the nose and hanging from one motor wire. Fortunately I was able to land the thing with no further damage. Clearly the motor was a bit too powerful for the airframe.

After rebuilding the nose I fitted a Purple power PO2834 1160 motor with an 11x6 folding prop. This gives about 230w. It now still climbs well and the performance is spot on. I'm still dabbling with the CG but very happy with the model. It catches lift well and has a good glide ratio.

As it copes with most normal windspeeds it is regularly flown. I can remove the prop and cowling and replace with a full grp nosecone for when I attend slopes with strict NO MOTOR rules.  Much fun !!

 

Edited By Dane Crosby on 25/10/2018 16:28:50

[buster prop]

Hi DC.

I see that your Cliffwhacker has a bolted-on wing and fancy wingtips. BTW I like the colour scheme. The dowels and bands on mine must be quite draggy but it would take severe surgery to adapt the model now, should have thought of it during the build. I did think about making mine a powered version once, but will leave it as a slope soarer as I’m really enjoying flying it. Is your Purple Power motor reversed so that it fits behind the front former? That’s the problem with electrifying glider designs, you often have to fit an extra former to support the motor backplate unless the motor’s reversed.

Our slope is also strictly for gliders, being NT land. I have flown a Radian there with the prop banded to the nose, just had to remember to leave the throttle stick alone! The only problem was landing, it just wanted to soar to great heights. I have a MPX Solius too and wonder how that would go off the slope. Would look nice with the glider nose cone if I could get one.