Tony Nijhuis' new Vulcan

[Tony Bennett]

i must try to find my copy of the free plan and see how a depron version would turn out weight wise.

though the 80" one i built came in at 6lb with battery and single pusher prop.

[John Laverick]

Not posted for a while, but have still been busy building. Here's my pusher version, maiden flight yesterday and I loved it!! great sound when you stick her on full throttle, I didn't think I did, but I must have built her tail heavy. Had to go down the cutting the nose off and sticking the batteries right up front route? First chuck was a damp squib, no damage so picked her up, stuck it on full throttle and give it a mighty chuck. It's all she needed. trick is to throw her with the nose pointing downwards, because with full throttle she wants to go straight up and into a stall. As soon as she bites she's away. You have to be brave. just needed a bit of up trim and a couple of clicks on the aerilon and she flew straight as a die. I got confident after a couple of minutes and started to chuck her around. Great fun and fast. You have to keep the speed up on the turns because she'll want to slide out of the sky, landing is the hard part cos she doesn't want to stop gliding!!! I tried the up elevator tip as given by Tony but she still landed a good couple of hundred metres away from me. I had her up for about 10 mins and the batteries showed 3.81 per cell. Enjoyed it so much I ordered another set of batteries.

[Mark Kettle 1]

John congratulations on your maiden, sounds exciting what you did. Can I ask what is the size and type of motors you used? Props etc? Reason I ask is because I want to get some similar for my version of the model.

[Erfolg]

John

Congratulations.

I will add my pounds worth, from experience with my own Delta. When approaching to land, with power off or slightly on, i just need to start lifting the nose, and the model will start to descend quite noticeably, due to drag rise. There seems to be no danger of a conventional stall, at worse it seems to flop down, like a pancake.

[Martian]

Yes congratulations ,she looks great

[Steve Bell 3]

Well done John

I was beginning to think this was going to be another white elephant . I'll be dry fitting everything to check where the battery needs to be located in order to balance the model before I cover it . I don't think you've built a tail heavy model as when you look at the plan most of the weighty bits are behind the c of g.

[John Laverick]

Thanks guys, Mark I've got her on two B28-47-18s 2100kv in-runners, two 5.25 x 4.75 electric props, two 50 amp esc and the suggested 3s 5000. I got the motors and esc's from Hobbyking, and the battery from BRC Hobbies.

Made a bit of a boo boo today, I was so happy with the first couple of flights I couldn't wait to get her up again, tried this afternoon, I knew it was too windy, and I had that nervous feeling when you know it's not gonna go right but your're gonna do it anyway!! A big slab shaped wing is only gonna do one thing in a strong wind and that is point upwards and then come straight downwards again. After two nose dives and a damaged nose, I got her up the third time with an almighty chuck. I had to get her flying cos if I took her home without getting her up I wouldn't have flew her again. Anyway turns out she can take quite a bit of punishment. The nose damage is after two full nose dives into the ground, the nose cone is detachable so that probably helped lessen the damage. Erflog, I was much more aggressive with getting her nose up for the landing this time and she landed a peach. I don't mind that she's damaged, cos I like fixing things!!

[Mark Kettle 1]

Thanks John, for the info, I -or should  I say we had a similar issue with the nose on a white Vulcan after a mid-air with another plane, it's been fixed and flying again as I'm sure yours will be. Pictures of said repair. 

...weight attached to ply tongue inside whilst glue dried.

Edited By Mark Kettle 1 on 05/04/2015 19:47:34

[Erfolg]

John

I am really pleased that your landing became a no event.

I must confess, that i found my delta a handful at first. The strangest thing,is that I now fly it all the time and see it as extremely predicable, That has come from the experience of flying it all the time. I now know, that rather than being a theoretical occurrence, that when flying that deltas are really low drag, that is until they start to turn, no, that should be when that angle of attack goes up, then the drag increases disproportionately. The other aspect, is they do not normally stall conventionally,they tend to stall in a flop, rather than the nose down stall.

I also no believe that all aerobatics need to be done at pretty much full power, then not a lot goes wrong, due to the AOA thing. Rolling out out loops is dead simple on power, on low power, almost anything can happen, that actually means skewing out'

I ofen think it is a pity that our models suffer damage in the trimming out period, where they are a handful, yet when trimmed out, what were the issues?

I am very hopeful that the damage will be repaired successfully, and will from now on provide a lot of pleasure,

Our own club much larger Vulcan has flown successfully now (on saturaday), that means without the audience, never mind the pilot, filling their pants. It looks fantastic, Our club pilot, on viewing the video,of an earlier flight,, is incredible. It seems that deltas are not that easy to trim out, I must have been very lucky.

[John Laverick]

It's all part of it Mark, I've built quite a lot of models which I haven't flown for fear of them crashing!! However I had a word with myself, and once I accepted that they will come down in ways other than intended, I feel much better about doing a maiden, and I tell myself I'm the one in charge and I concentrate on flying it instead of panicking !! I actually had one I'd built three years ago and only flew for the first time last week!! Crazy cos she flew like a dream.

[John Laverick]

Erfolg, Would be nice if you could just give your pride and joy to someone to trim it out before we get our hands on it. i'm not a member of a club so I have to do things the hard way. Still it's a fantastic sense of achievement building something from a piece of paper, to getting it into the air all on your own!!! Great buzz driving back home to tell the wife and kids you've had another successful flight over NAZI occupied Germany!!!!

[Mark Kettle 1]

To help John you'll see on this video here Tim land his Vulcan from a 'high angle of attack' and from the slow down - almost stall he brings it in before it all speeds up again - see this at 2:47 on the time clock within the video.

**LINK**

Edited By Mark Kettle 1 on 05/04/2015 20:45:34

[Glenn Philbrick]

Tried to fly my Vulcan on Wednesday with not good results. I have tried to post a Video of the launch but it will not download into the album. The net result is that the nose is slightly broken it will repair but at present I'm not sure if its worth the effort. I cannot understand why I have had to put the batteries in the nose which is clearly not designed to take them. I have not put retracts in or a rudder servo so have avoided the weight of these behind the c of g.

Even with the fans uprated there does not appear to be enough power to get it airborne, and I can see that even if I do mange that it will only take a bumpy arrival to break the nose again.

If i was to built this again then I would most definately use the ten bladed 4s fan units and reinforce the nose to at least survive a few knocks.

[Steve Bell 3]

Bad luck Glen I'm still plodding on building my twin pusher version it is way tail heavy. It will definitely need the battery in the nose If I'd known before sheeting the fuselage I could have built in a battery box now I'll need to cut into the front and then rebuild it. I also think it may be wise to build in a hard point for a hook to bungee launch it as air speed seems to be a launching problem , well back to the grind .

[Glenn Philbrick]

Hi Steve,

I have decided to repair my Vulcan, and this evening have carried out the cosmetic repairs. However I now need to reinforce the nose where the batteries are fitted so that I stand a chance of it not breaking up due to the light build in this area. One of the posts on here made me think, perhaps I could just fill the void with expanding foam and then cut out suitable shapes to take the batteries. The other alternative is to use light ply and put some struts in to take any sideways load back to the wing area, how strong would the foam alternative be and would it break through the balsa fuselage sides as it expanded any thoughts?

You can see in the attached photo were I made a hard point for my tow hook. One problem we came across using a bungee was the distance between the rails need to be quite narrow, otherwise with the c of g being were it is the Vulcan will adopt a nose down attitude on the rails which does not help. I will try to find a way to put the Video of the bungee launch so it can be seen that although it went off OK all it did was run along the ground.

[Glenn Philbrick]

Here is the photo!!

[Martin Rowe 1]

Anyone else wonder why Tony has not turned up?

He he must know we are all having problems

[Martin McIntosh]

Exactly my thoughts too Martin.

Some of my club mates launch fast EDF models from a ramp made from plastic piping. It is quite short but is angled up just like a V1 ramp and works well. Would defeat the object of making a nice retract version though.

[Martian]

It's sad so many tales of woe after all the hard work you guys have put in ,I have been following all your builds and must admit it is disappointing that Tony N hasn't commented at all

[Former Member]

[This posting has been removed]

[Alan Jarvis]

I have owned and flown many ducted fan planes some of which ran two fans from a common chamber without issue

Having built this Vulcan it is certainly underpowered and the batteries needed to be placed well forward from the design for the CofG.

I believe this is the first DF that Tony built and I am not sure it got it right power wise. Otherwise the design of the fuse and wings are good.

I am presently fitting a single motor and folding prop on the tail cone and will bungee launch.

[Andy Fox]

There were similar tales with the original 72" Lanc build.... Many builds were under powered/heavy and crashed early on... Mine for example, was much, much heavier than Tonys prototype... I believe the key here is down to wood choice and keeping things extremely light in the build. Fortunately, with the Lanc, I was able to change the motor setup to provide adequate power to get her flying.

Not sure what could be done with an EDF setup... Has anyone tried launching from a slope to get an idea of the flight envelope?

[Glenn Philbrick]

I think that the problem is a combination of two factors. One the fans as suggested produce nowhere near the power that is stated by Hobby King. When I looked at the reviews of these units it became obvious that the outputs were variable, some good but most poor. I only assume that Tony must have got hold of good units. The other factor in my case was the wood selection, something went wrong from the start, I had no 4" balsa but had too much 3" and | also had two boxes delivered, I have enough left over to build all sorts of planes as long as they are out of 2.5mm balsa.

In my build I believe I took these factors into consideration, my Vulcan wings were sheeted using 2mm soft wood, The model was not covered at all but poly ceed and rubbed down then spayed directly on top. This gives a good finish but no added strength.

What caught me out was having to put the batteries in the nose, This is clearly not designed for the mass of two battery packs hence I was not surprised when mine broke when all it did was run along the ground.

The bungee that we attempted to use could only be loaded up to 4kgs which I think was not enough, Looking around on the web the suggestion is that you need three times the weight of the model, ie nearer to 6-7kgs.

As for launching it off a slope, yes I'm sure it would fly at some point but I would take a brave sole given this models fragility.

I wish I could post the video of the launch, We used a Hobby King launch platform so has a reasonable angle of attack, however due to the C of g being inside the rails it tended to put the nose down.

If I have rambled on it is only because I cannot stand master chef so have left the room.

[Martin McIntosh]

I am a little surprised that many are having c of g problems with this. Mine is the DF version with retracts and with the batteries in the designed position it is spot on. I did not, however, use the CNC pack which is loaded with cheapo light ply, but used balsa for everything bar the u/c ribs.

I have not as yet got it to ROG and doubt that it ever will.

Built many of Tony`s designs including the three Spits, 11 ft. Lanc., the Mustang, and am now just completing the 62" Hurri. and cannot fault any of these because they are the type of models I like and the build is very similar to the way I do my own, but this one is a definite boo boo.. Sorry.

[Piers Bowlan]

I have been watching this thread with interest, a Vulcan has always been on my 'build list' but I don't have time for such a complex build just now. So sad to see so much thought, time and skill invested in these builds without a sweet flying model at the end of it. Perhaps I should build a PSS version, but it would seem the nose would need strengthening somewhat.

It looks like 4 X 50mm fans simply are not up to it - too much weight (or too much light-ply) for too little thrust. I wondered if two 70mm fans on 4s might be more efficient overall but that would mean an ugly bulge under each wing to accommodate the fans. That is, unless the model was scaled up, which would be heavier and produce more drag. A bit of a vicious circle!

What does your Vulcan weigh Martin, including batteries? Lots of wing area there, so perhaps the wing loading is not too bad, just the lack of thrust is the problem with the design. Long tail pipes too; not good for efficiency.

I wonder if Tony has his 78in span Vulcan flying yet or is he keeping his head down at the moment? 

 

 

Edited By Piers Bowlan on 13/04/2015 11:32:18

Edited By Piers Bowlan on 13/04/2015 12:05:01