RES Eagle

[Phil Morrell]

I am in the final stages of completing my RES Eagle built from scratch off the RCM&E plan. I have a question for Ton or any other builders. Did you move the position of the spoiler servo forward to give more room for the linkage. Excellent model and looking forward to flying it soon.

[buster prop]

Phil, Please let us know how it flies and if you can, post some pictures. I have the plan for the RES-Eagle and it’s next on my build list. Btw there is a build thread on here started by Ton, the designer. Looking at the plan there isn’t a lot of room for moving the spoiler servo it’s between the carbon spar and the front wing bolt. Our club intends to run F3 comps next year for 2M towline gliders and the RES Eagle looks like a good candidate.

[Phil Morrell]

Hi , Thanks for your reply, You are correct , there is not a lot of room for the spoiler servo and linkage. I have mine installed but need some work to do on the linkage geometry to make the spoiler fully deploy. we have at least four Eagles in build by my fellow club members and we intend to introduce RES gliders in our summer Wednesday evening comps next year. Currently we fly open gliders on a 20 lb max load bungee, far too much for an RES, we are therefore bringing in a couple of 10lb max RES bungees and will allow the RES models to compete against the open models, mainly 100"" models. It will be interesting to see how the RES models compare against the 100" models. Can't wait for next year to see how the RES models fair. My picture shows my part built Eagle

[buster prop]

Phil, I’ve ordered a kit from SMC. They rang to say there will be a delay while they get 6mm carbon spars. I think the outer panels have had the spar size increased from 4mm on the original plan to 6 because of flutter problems on launch. Our club has run electric glider comp’s for the last few years and are now proposing an F3 bungee launched 2M class so I’m having a go. I’ve been a regular E competitor so I’m used to flying gliders but not experienced at bungee launching. Other people manage and It doesn’t look too difficult as long as the glider is set up properly with no warps. Your model looks good, has it flown yet?

[Steve Houghton 1]

Buster prop - bungee launching is easy enough. I have set up a 'launch mode' on my tx, so activated by a spare switch in flight modes and it gives a little up elevator without you having to hold elevator on the stick during the climb out. My model has flaps so the flaps are activated in launch mode also. Once the model reaches its max height and levels out, pushing down elevator on the stick unhooks the model, (if it already hasn't done so) but also resets the elevator (and flaps) to neutral. The only thing you have to do during the climb out is control direction using the rudder.

[buster prop]

Steve, I tried bungee launching a few years ago and although I got the glider unhooked it lost quite a lot of height. Thanks for the tip about having slight up elevator for launch. With electric I have a bit of down to stop the climb being too steep as the model can power stall or even loop. I have seen skilled pilots hover the plane at the top of the towline, pointing into wind, then stretch the bungee vertically and ping the glider off gaining more height. Something to learn after a few successful launches I think.

[Phil Morrell]

Hi Buster Prop and Steve, bungee launching is fairly straight forward. Just a few key points: try not to over stretch the bungee, measure the load with a spring balance if you can. In our club comps we always measure the pull load when we set up the bungess. With open 100" gliders we aim for around 15 to 18 lb but reduce a couple of pounds for 2m models such as Gentle Ladies, a simple spring balance used for fishing will do the trick. For an RES model such as the Eagle don't go over 10lb or you risk breaking the wing. Don't pull up too much elevator on the launch, best to just let it go without any elevator input at first at just concentrate on keeping it tracking straight, once you have gained more experience and know the model better only then start to pull more elevator. I always find that it is best to let the glider fly off the bungee at the top straight and level, pinging and stretching the bungee is great for gaining that little extra height but if you get it wrong you end up with the model stalling and loosing a considerable amount of height. Like most things practice makes perfect, take it easy at first and then you will soon get the hang of it and wonder what all the fuss was about.

A number of my fellow club members have recently ordered Eagle kits and found the carbon supplied for the outer wing panels was 4mm not 6mm. SMC have responded very quick in sending out replacement 6mm spars. They must have now alerted their kit supplier hence the delay but I am sure you will get your Eagle soon.

Not flown mine yet as I am waiting for our new 4kg RES club bungees to arrive. I may leave the first flight until spring next year but if we get some reasonable weather before then I may give it a go. Once I get it flying I will post any flying shots and let you know how it flies

[buster prop]

Hi again Phil. My RES-Eagle build is coming on nicely, got the fuselage, tail, one wing tip and the centre done but not covered yet. Looking again at your part built model I notice that you didn’t add the wing tip dihedral. I did because Ton altered the design after flight testing and the plan includes the polyhedral wing. The outer spars have to be angled up at R14, Ton said that the outer wings should be built flat and the spar and l.e. cut and angled up afterwards. I didn’t think that would be easy to do accurately so I made the spars first and built the panels on. Now I have to make sure the other tip has exactly the same dihedral! Btw, SMC supplied plenty of 6mm tube and 4mm rod, which fits nicely into the tube for the wing joiners.

[Phil Morrell]

Hi Buster,

Thanks for your latest posting. My Eagle is now finished and ready for it's first flight. I have now added the tip dihedral and in addition bound the small carbon tappered joiner to the spars with some fine Kevlar thread. Finished weight is a little higher than Ton's prototype at 570 gm. I am still happy with this weight as in comparison it is 200gm lighter than my trusty 2m Gentle Lady that always performs well in our club comps. Please keep me posted on your build and flights once you have finished. We now have 5 Eagles in build in our club, I will keep you posted on our builds

[Phil Morrell]

[buster prop]

First of all, your model looks great! I am going to use transparent purple Profilm and solid white. I don’t have any transparent yellow but plenty of white left over from another build. The fin and tail plane are now covered, I understand now that you intended to angle up the wing tips, and your earlier picture showed them in the pre-bent state. I’ll put up a picture after Xmas if I can remember how to put pics onto this forum. I notice you put holes in the elevator to save tail weight, bit late for me now as it’s been covered. I did use a carbon rod joiner instead of piano wire so I hope that helps. Next job is to make another wing outer and then covering and fitting out including finding a small servo for the spoiler.

[Phil Morrell]

Hi All and Happy New Year, pleased to report that I have now flown my RES Eagle at our annual club New Year's Day meeting. I am very pleased with the performance. It took me a couple of launches before I could get the Eagle up to the top of the bungee. The first launch had too little elevator resulting in a low fast trajectory with the model pinging off the line early. I pulled too much elevator on the second launch resulting in looping off the bungee. Third time lucky with the elevator trim set with a small amount of uptrim and the Eagle tracked straight to the top of bungee launch with very little elevator input. Once off the line the Eagle flew nice and steady. I managed a further four flights reaching the top of the bungee on each occasion. I found it a bit sensitive to elevator but ok once I got used to it. Conditions were overcast with a 5 mph breeze so there were no thermals about. Flight times were between 2.5 to 3 minutes, very happy with these times considering the conditions. Another club mate also maidened his Eagle which also performed well. A great morning's flying and now looking forward to the spring when I can try the Eagle in better air. I have included a number of photos from the day captured by my club mate Stewart Bennett

[buster prop]

That’s great Phil, I hope my RES Eagle flies as well as yours, which looks good too. I’ve built the other wingtip and about to start covering it all. I’m hoping the RES Eagle is as good as the lightweight 2M gliders from Hyperflight. It’s heavier but has about the same wing loading thanks to a broader chord wing. Possibly better in typical UK windy weather. There’s another RES Eagle thread on here and I’ve put up a couple of build pictures.

[Ton van Munsteren]

Phil, The RES-Eagle is looking great thanks for posting the pics.

[Phil Morrell]

Thanks Buster, I must start using the other RES Eagle thread and thanks to you too Ton, you have produced a really good designed lightweight glider. We now have 2 complete in our club and a further 3 in build. Looking forward to seeing how it performs in our summer evening comps.

Cheers

Phil

[Ton van Munsteren]

Your welcome and great to know there already are 2 RES-Eagle's flying and there should be more to come.

Looking forward seeing pics of all the models and how they perform in the competition.

Cheers, Ton

[Sussex Pete]

Thanks to all for this log and discussion. Two of us in the East Sussex Soaring Association have RES-Eagle short kits for the coming flying season. My pile of nicely CNCed wood is just on the workbench so it's time to read all the build logs! I'll post my own on a separate thread but it's good to see several are coming along. I like the look of F3-RES as well as the "postal" 2-m comp that BARCS run (see eg the F3-RES UK Competition Interest thread). Must be a few builds in progress as all model shops seem to be short of 6mm x 4mm carbon tube!

BTW, I've flown a 38oz 100" Kamco Kloudrider off a European-standard F3-RES bungee and it is really good fun, especially into some knots of wind when I can kite the tubing off the ground and re-stretch it on the way up 8-) Launching a much-lighter Eagle with the same energy should be quite exciting...

[David Hall 9]

My RES Eagle kit arrived today. It looks good.

As launching by bungee is a problem at my local flying site, practice would be difficult, so I intend to add a motor for practice/sport/F5J flying. I guess there's no reason that competing in F3RES comps would be a problem (with the spinner & props replaced with a simple cone).

I noticed that the box is labeled as "for beginners"... is that the building or flying, or maybe both?

[Sussex Pete]

Hi David great to know more are on the building board 8) There's a separate build thread at RES-Eagle Glider RCME March 2018 where a few of us are sharing ideas. Someone somewhere suggested building one wing and both Red and RES Eagle fuselages. The glider fuselage will weigh a lot less without motor and Lipo. Also the BARCS 2020 postal competition is off a 60m bungee to fit smaller fields which might work for you?

Edited By Sussex Pete on 01/02/2020 08:24:04

[Piers Bowlan]

Out of interest Pete, do you know how much the battery and any extra ballast in the nose weighed? I wondered how that compared with the weight of a suitable motor and LiPo.

[David Hall 9]

Posted by Sussex Pete on 01/02/2020 08:21:58:

Hi David great to know more are on the building board 8) There's a separate build thread at RES-Eagle Glider RCME March 2018 where a few of us are sharing ideas. Someone somewhere suggested building one wing and both Red and RES Eagle fuselages. The glider fuselage will weigh a lot less without motor and Lipo. Also the BARCS 2020 postal competition is off a 60m bungee to fit smaller fields which might work for you?

Edited By Sussex Pete on 01/02/2020 08:24:04

A separate fus is a good idea... For a while, I have been trying to place the two wing bolts at the same place and spacing on a range of my 2m Eglider models (with some level of interchangeability in mind), maybe now is the time to utilise them and build the kit fus for bungee.

[Sussex Pete]

Posted by Piers Bowlan on 01/02/2020 12:20:30:

Out of interest Pete, do you know how much the battery and any extra ballast in the nose weighed? I wondered how that compared with the weight of a suitable motor and LiPo.

Hi Piers, no, not yet - my RES-Eagle is still on the building board - but I hope to need minimal ballast. The nose lever length looks reasonable on the plans for hardware to balance the tail. I'm using a 4xAAA square 1000mAh NiMH (50g), 2 x Hitec HS85-MG servos (total 44g) and a 4ch Rx (7g) installed front to back in that order and as far forward as possible. So the radio kit will weigh about 115g with bearers, a switch, etc.

I will leave final installation late in the build so I can shuffle weight if needed. There are lighter servos but I just love the HS85-MG for great torque and metal output gears that don't strip when a control surface or horn snags on landing (that's what disposable plastic clevises are for!). I have used loads in slope soarers and none have failed me even in heavy "arrivals" 8-)

I also aiming to build the tail-end lighter where possible - a failing on an earlier 100" soarer I built where I went for tail strength over weight but needed 7oz (200g!) of lead to balance it!

Edited By Sussex Pete on 03/02/2020 08:53:02

[Phil Morrell]

Hi Piers,

My RES Eagle needed an extra 20 gm of nose weight to achieve the correct C of G. I have used Emax md11 metal gear servos and a 50 gm AAA size envelope square flight pack. Get the servos as far forward as you can leaving yourself enough room for the Rx and battery. I had to use extra long 22swg piano wire snakes for the pushrods, gliders distribution in Newark stock them at 1.6 m long and are ideal for the RES Eagle. I tried to get the tail end as light as possible by sourcing low density balsa and also adding lightening holes to the elevators .I used thin gauge aluminium tube from the mounting poles of my garden solar lights to cut the holes, they cut a clean 25 mm hole without having to sharpen them.

Cheers

Phil

[Sussex Pete]

Thanks for the data, Phil - given my servos together weigh about 20g more than yours, with luck I'll not need any lead at all!

[David Hall 9]

Thinking about how to power the Eagle (E-Eagle?)..

I guess that for my purposes, climbing to height on the motor is for sport/practice flying, quite a small power setup would be fine. No-one would care if it took me 40 seconds to get to 100m.

If F5RES ever became a comp class in the UK, what would the likely requirements be?