Ian's Cox Flight Contest progress

duke.johnson wrote:Thanks, for the update.  I was not cutting you rideas down, hope you knoe that.  I like what you have done and hope to give it a try soon, a friend has plans from the 40's that I'd like to use.  RTP lives again!

I realise that your input is constructive but you and Lieven made me realise how much "trial and error" I can be. I only really solve problems after they have occurred - hence the waggly pole at the beginning! I launched that plane to the ground over 10 times before I got it in the air!

I am interested in re designing a pole. A wing over with this pole would be a disaster - the ring would catch at the top.

Longer lines could mean a lower pole. I am limited by short lines - for hand launch I need to be at the top of the pole for landing at the bottom. (Otherwise it would be wing down!)

Too low a pole (a peg) and lines would drag along the floor.

I have to fly it up and down the pole.

Also - I fly at an angle using the throttle and elevator to keep the speed down. If I level out the speed is phenominal - well, not really but on short lines it is too fast. If I slow the engine down - stall time!

All these are after thoughts! They prompt more "trial and error"!

All input and ideas are appreciated.

Great build Ian. The videos were very entertaining as well.

Shawn

ian1954 wrote:

OVERLORD wrote:Good idea Ian, and I love the design-as-you-go-along bit. I bought recently an umbrella foot in resin with a weight of 30 kg. would such a weight be enough to hold the pole steady?

Lieven

I don't think so. I had to increase the area of the base to stop the pole from toppling over. I think there are two choices :-

As Ron suggested - dig deep and bury a substantial length of pole
A very large secure base - not sure how much weight plays a part.

Best of both worlds would be to dig a 3ft hole about and set the post with an 80lb bag of concrete. backfill and that thing ain't going nowhere.

Cribbs74 wrote:

ian1954 wrote:

OVERLORD wrote:Good idea Ian, and I love the design-as-you-go-along bit. I bought recently an umbrella foot in resin with a weight of 30 kg. would such a weight be enough to hold the pole steady?

Lieven

I don't think so. I had to increase the area of the base to stop the pole from toppling over. I think there are two choices :-

As Ron suggested - dig deep and bury a substantial length of pole
A very large secure base - not sure how much weight plays a part.

Best of both worlds would be to dig a 3ft hole about and set the post with an 80lb bag of concrete. backfill and that thing ain't going nowhere.

Better still, since it is lawn, set a pipe, PVC should be fine, and then you can slide the post into the ground and take it out super easy.
Phil

The saga continues!

The medallion engine is one that I have rebuilt. New cylinder and piston and a brass crankshaft bearing. It is developing more power (i am flying it to run it in!) and causing the pole to rock beyond my tolerance.

Every comment is welcome but Phil suggested a "pipe" in the lawn. This set me thinking!

I was sure that at some stage a had set a tube in concrete for one of those "women's" gadgets. I think they are called GirlyWigs or Whirlygigs. Anyway, something to do with drying washing!

So I set about investigating and .... lo and behold...... under the grass



All I needed was an aluminium billet to fit,



a bit of machining





and



already for off again

I have been flying the thing most of the day. Took a break to modify the pole as previously and then followed Duke and changed to a single line!

Rather than bore everybody - here is a short snippet - take off with one line!



Now rather than preach my successes - here are some out takes! The lines detaching from the pole and crashes!



Also apologies for the camera work. I tried to enlist assistance but after seeing the plane fly off into the bushes - my request was refused.

I even supplied protective gear!

ian1954 wrote:
Also apologies for the camera work. I tried to enlist assistance but after seeing the plane fly off into the bushes - my request was refused.

I even supplied protective gear!

Ian
My wife would like to hear her side of the story.

I think you need to work on the CG and the attachment point. By my understanding, you should have the CG somewhere on the LE or just in front of it. And the attachment point should be ahead of that. I'm trying to finish two other planes before I start another, but can't wait to build a RTP. My friend pulled out his pole gear and is modifying an electric plane to take a Cox engine right now. Looks like you are having fun! How much time have you racked up with that thing!

As has been said before, I am very much "trial and error". It flew level and slow on the old set up - two lines and the waggly pole - this morning. (Too boring to video - I didn't even record the time of one flight - I came inside for a cuppa, biscuit and cigarette and didn't notice the engine had stopped!)

I had adjusted throttle and elevator. However, the engine has picked up speed and I have also been messing about with the transmitter - linking throttle and elevator - so a low throttle had some up elevator. This went horribly wrong (well not horribly but annoyingly!) at some point and the combination of speed, single line and a not so waggly pole resulted in the up and down motion you could see. I wasn't able at first to trim it out!

I am going to revisit the attachment point and c of g but first I will try a different propeelor. I need to be able to slow it down. On such a short line it really spins! It is on a 6 x 3 at the moment. A 6 x 4 should clam it down a little.

Must learn not to make so many changes at one time!

This morning I racked up close on two and a half hours. This afternoon about three quarters of an hour. I will have to check my sums - I write the times down and include the one second flights! Nothing yesterday but last weekend .....................

A 6x4 might lower the RPMs some, but I would be surprised if it doesn't fly faster. Maybe a 6x2 or a 7x3.

The next size up I have is a 7 x 4 wooden propellor. I will have to make a bush for it.

Two changes in one - slow the engine down and add more weight at the front!

Thanks everyone for your comments - even if I haven't mentioned you directly!

Ian
You are doing way better than me on time this month and my RTP plane is still just a dream.
Duke

Ian, how about putting your 6x3 on backwards. That will certainly slow it down, as it's very inefficient that way, but still pulls in the same direction.

Another good suggestion! I will try it.

duke.johnson wrote:Ian
You are doing way better than me on time this month and my RTP plane is still just a dream.
Duke

I must confess that it feels a little like cheating!

I don't have to travel anyway, have "waitress" service and it is almost like flying on autopilot. I would clock more time if I didn't keep fiddling but I am determined to wing over and loop the loop!

Technically, I should be able to fly in the rain - Once in the air I could control it from indoors! 

I can set it flying level and walk away for 10 minutes! (Well 8 minutes - it sometimes makes 11 minutes but sometimes not quite 10 and then I can't log it because I wasn't there!)

I am also building another so watch this space!

However, I have a queue of engines "mid-restore" and another queue "mid-build" (It is too hot in the workshop at the moment though!)

I was a little put off about the RTP in the control line contest, but the boss says it's ok. And everyone can do it if they want, so fairs-fair. Please don't take it the wrong way, I'm good with RTP. I just hope I can get one going before you get a million hours racked up. 

Put up a strategic umbrella and you can stay dry launching in the rain. However, I have it on good grounds that with a forward facing intake it doesn't take much water aspiration to shut down a motor.

Phil

What's "RTP?"

I took my Cox powered contest plane out to play yesterday, but got run off by a thunderstorm before she could log any time. I'm still at about 9 minutes total.

RknRusty wrote:What's "RTP?"

I took my Cox powered contest plane out to play yesterday, but got run off by a thunderstorm before she could log any time. I'm still at about 9 minutes total.

"Round The Pole"
See the videos earlier in this thread.

duke.johnson wrote:

RknRusty wrote:What's "RTP?"

"Round The Pole"
See the videos earlier in this thread.

I saw them. Sorry, I just woke up. 

 

duke.johnson wrote:I was a little put off about the RTP in the control line contest, but the boss says it's ok.  And everyone can do it if they want, so fairs-fair.  Please don't take it the wrong way, I'm good with RTP.  I just hope I can get one going before you get a million hours racked up. 

Heya Duke,

The way I saw it was if he put a bellcrank and control handle on it then it would be the same as throttle assisted CL. The runtime is engine and tank size and nothing is stopping anyone from building the same plane with the same tank. Heck, If you want to put a 2oz tank on a 1/2A then by all means do so.

The real quandry is he is the only one doing it and he has to go somewhere, If the players feel it's more like RC it can go there. I certainly don't want to upset anyone. I usually ask for feedback and get very little.....

Ron

Ron-Like I said, I'm good with the RTP.  I just wish I would have thought of it first.  Now I'm going to have to build yet another airplane  , like I have time for that. 

Ian- I hope you get it dialed in the way you want it. Look there goes Ian's RTP again .   Minute after minute after minute. Jolly go show chap.  Or something like that.

Where are those drawings for the RTP plane.    

I am not that competitive!

I like the idea of the competition to promote "Cox awareness" and to get more people involved in the hobby.

I look at this, though, from a different perspective.

I have mentioned before that it is difficult to fly ANY I.C. powered model locally. I.C. engines are banned in all local parks and open spaces.

The distant clubs have strict rules on noise and although we may be talking sub 20 miles away - crossing London may take 2 hours. Not many Cox engines can meet the criteria.

2 minutes walk and I can fly electric "Park Flyers", 10 minutes walk and I can fly electric "Beasts!".

A lot of people may be in a similar situation.

This combined with age, eyesight and other commitments puts on a few more limitations. Time is another factor!

The idea of RTP for me allows Cox engine flying (well sub 049!) in a limited space (you have seen how limited!) and relatively safely. (debatable! I have been whacked, thwacked, bruised and cut!).

Anyone can do this! The model is the BlackHawk's Night Hawk - control line. I chose a built up fuselage to hold the receiver and battery but any control line plane can be adapted.

I started building this on the 23rd June, it was ready to fly on 13th July (I also work full time!) and I have clocked up quite a few hours after two weekends.

It is a "test bed" - lots more ideas - diesel head, in flight refuelling (dream on!), flaps ..................................

I do not mind if it cannot be classified as CL or RC and is excluded from the competition results (or put to one side awaiting more RTP entries and preferrably longer lines!)

It is the spirit of the contest I am interested in and a way to get more people of any age or experience involved in what appears to me to be a more controlled environment than pure CL or RC.

This entry of mine must not put off other competition entrants.

Get out there and log the time! If I start to lead I will stop logging - I only want to give members and viewers an idea of what is possible!

Like I said, I'm good with the RTP idea. I didn't mean to start something. I like the idea and now have a reason to try RTP. I never win contests, so I'm hear for the fun and to be apart of something cool.