vintage RTP flying

[thunderstreak.keith]

This is going to be a project into as yet an unknown/new form of flying to me. (at the moment) As you can see I have aquired a 32" span lancaster and a 24" me 109. The lanc is fitted with what looks like 2x280 size motors (inboard) and all wired up ready with a plug in the wing tip.same with the me109. I havnt tried them yet. Also I have the units for the power supply and all the flying wires. All I need do is make a pylon and then set it all up and hopefully get everything to work. these were all from the early 80s indoor club flying that my uncle used to do. I have found various methods for making the pylon but all use mecanno parts so some research is going to be needed. the aircraft will also need recovering (the wings anyway. so we shall see what comes of this, interesting to say the least.however it will be taking a low priority but I will persevere. the old aero mags from the 60s and 70s are certainly helping. will try and keep this thread going if i can, hopefully with some success.

[Andy Green]

I flew RTP back in the day, the original electric flying. Still got a couple of plans somewhere.

Andy

[IanN]

I did a bit of that, back in the day. No surviving kit or models, but this Ray Malmstrom Saab J29 was great fun. Cheap, easy and tough - what more could you need?

[Simon Chaddock]

Thinderstreak

I used to do a lot of RTP. A one stage it was the only sort of model flying I had access to.

Still have many of them. Indeed my Fokker Triplane 'avatar' is one!

A geared 'slot car' motor and 18" span. It flew very well and despite being 48 years old with a bit of TLC it probably still could.

[Chris Bott - Moderator]

I'm not sure if Ballards are still in business?

They used to be a very good supplier of RTP kit and models.
There is a website, but to say it looks a bit tired is probably being generous in 2014

Ballards RTP

[Alan Gorham_]

I used Ballards to buy a pole, some lines and motors a couple of years ago.

[thunderstreak.keith]

well I didnt think anyone was still interested thanks all, its given me a bit more motivation now. chris, as for the bollards, I could have had that as well with th pole etc but my sister drew a line at loading it in the car and is still up the attic in my uncles house in tonyrefail, (rhondda) pity that i live in somerset. there was a plan in the plans special mag for a kity hawk which would go nice with these pair i`ve got. thing is it may be a bit heavy being all balsa covered so I may have to alter it a bit to take a tissue covering. but that can wait I am going to have to connect everything up here first to check it all out. like i say its going to be a project on the side to take me over winter, got too many unfinished to finish first and a broken wing minimoa. sad that was.

[Dave Bran]

I have all the electrics, power supplies, controllers, couple of poles and weight bases, spares, and some balsa profile planes, Spitfire, 109, Lightning, Thunderbolt. these have elastic band fitted motors for quick changes of airframe as they were used for round the pole pylon racing and combat in a school club!!!

Also have a bit tatty but much bigger balsa frame and tissue F16.

[Alan Gorham_]

It's good fun isn't it? Especially indoors on a cold, dark, rainy, windy night in winter when you haven't been able to get out flying outdoors for weeks.

[Peter Miller]

RTP was the only way that I could persuade the KK scale models to fly well.

In 54 I was with the Regents Park Model flying club for a short time. They used to fly Jetex models round the pole. These eventually were refined to a motor with a wire tail boom and shim copper or brass wings and tail. The fuel pellet was grooved up the sides for even faster burning. We all ended up crouched behind upturned tables for safety.

By this stage timing became impossible plus very smelly in a winter clubroom.

Then we started building KK and Veron solid model kits and hollowing them out to take Jetex 50 motors and these flew beautifully though I do remember a Vampire on which the tailplane caught fire which was spectacular. The smell still filled the club room.

[Tomtom39]

We used to fly RTP at our old ATC squadron drill hall after parade. Great fun. Like Peter , we also tried the Jetex motors but following a minor accident resulting in a not so small fire we were restricted to conventional electric motors. I still have all the gear that I bought from Ballards , although the pole was upgraded and better ball raced bearings were fitted on the head.

Your post has just given me the right encouragement to go into the loft and dig it all out (now just need a bit of room!)

(I also remember racing some I/c powered cars - our Sqdn leader used to have quite a collection - saw this being done again many years ago at the Model Engineering show at Olympia )

[Phil Green]

As young teenagers ours was a two-at-once home-made pylon mostly made of mechano. Models were trimmed to fly either high or low. Had a lot of tangles when two 'lows' or two 'highs' were accidentally mixed but mostly it worked well. Only short lines though as it was in my mates Dads double garage. We tried to do carrier deck etc.
We were big slot-racing enthusiasts too so had plenty of spare motors, Riko Whip and Riko Rocket were popular. Some of our 1/32 slot car motors were 70 watts plus!
Most of the models were simple all-sheet profiles, took minutes to make.

If I was to have a go today, I'd probably go for a simple pylon with a monofilament tether and ultralight indoor RC & lipo in the model on motor & elevator.

Cheers
Phil

 

Edited By Phil Green on 08/07/2014 20:16:48

[i12fly]

J had a go at that too! Even made a rig to operate an elevator via a joystick, cables and bellcranks. It worked but really needed more power from the motor and a bigger garden.

I strongly recommend you put a fuse in the line on the outputs from the power supply as sooner or later you will get a short on your lacquered wire. I understand that was a weak point with the KK power unit and killed off quite a few. I blew a few fuses but my power unit survived intact and was sold to a happy ebayer about 10 years ago.

[Phil Green]

**LINK**

[thunderstreak.keith]

simon lovely looking "fokker"(brings back memories of the live stan boardman joke on bbc that does,but lets not go into that 1) these are the bits I have to connect up. the big black hing with a dial confuses me. its probably a regulator as the dial says % input voltage. I presume this went in between the transformer and the pole connecting wires? any ideas? That roll of insulated copper wire weighs just over pound, so plenty of it there.

[thunderstreak.keith]

I will be connecting a 6v/12v (not sure which yet) to the 2 planes to see how the motors run, so that should be fun. Been told they havnt been fired up for over 14 years. On the subject of jetex rtp, i have 2 unflown f/f jets fitted with rapier units, might be worth a go on that 1. I know they used to do tethered cars in the 50s/60s mostly ic but a few of them were fitted with jetex units. Me thinks this is going to be a long project, so many options

[Peter Miller]

Jetex actually produced a car, I forget which size of motor they used. They also made a boat and a helicopter with two Jetex 50s on arms on the rotor head.

[Shaunie]

Hi Keith,

The black box with a big dial is a device generically known as a "Variac " although yours is the Regavolt brand as marked on the dial. It is a variable voltage transformer where the ac output can be continuously varied from 0 to input voltage (or slightly above in some cases). Presumably it is the speed controller and massive overkill but I'm sure works well in this application nevertheless.

Shaunie.

[thunderstreak.keith]

I thought so shaunie, wasnt 100% so was best to check. so that will go after the transformer and wires from that going to the pole to supply a variable voltage for motor speed? this is all new to me especially with antiquated equipment. I think health and safety wallies would have a field day yer. one other problem is the transformer shows a variable dc voltage output from 18-46v. would have preferred 12v but the system set up in the school gym all those years ago did work,so I am reliably told. Will check the motors out later today,

[Phil Green]

Motors/props/etc on Ebay - up in 2 hours

[Daithi O Buitigh]

I wouldn't worry about the 'over voltage' as there will be losses in the wiring between the source and the model anyway so 18 volts is probably fine

[David Burrows]

I flew rtp at Batley Rafa club when I was a member of Dewsbury model aero club
I built the ballards Lancaster and my own version of the Pitts
And flew combat fighting to the death
Loved it

[Simon Chaddock]

With these motors it is not the applied voltage that is the concern but the current. Any motor will have a maximum number of amps it is can handle so you apply the required voltage to reach that figure (hopefully the plane is flying by that point!). With long fine wires the necessary transformer voltage can easily be 18V or more.

I find it can help to go back to old Victorian concept of voltage as electric 'pressure' and amps as electric 'flow' rather like hydraulics.

If you have a long thin pipe it needs a higher pressure at one end than the other just to get the required flow to pass through it.

[John Olsen 1]

The Variac would go between the mains and the DC power unit. By varying the position of the knob you will be able to get any output Voltage you want from 0 to the maximum. For example if you are on the 18V setting on the DC supply and set the Variac to about 66 you should get about 12 Volts out. You can adjust this to get the maximum permitted Voltage or current at the actual motor, which will overcome the line losses. It might be good idea to get someone knowledgable to check out the Variac and the power supply if they have not been used for some time, and especially to check the connections if you are not au fait with this sort of thing. A Variac is not an isolating transformer, so the output side is just as dangerous as the mains. The DC side of the power supply will be isolated from the mains, but bear in mind that it is quite old and may not have been stored in ideal conditions. I wonder if a more modern supply might be a good investment?

John

[thunderstreak.keith]

just checked out the motor on the ME109. 12v 8amp spins the prop but no taxiing across the floor. 24v 8amp and she taxis quite fast but not enough. This was on the original length of wire that used to be used, so it looks like I will need all that voltage and alot more unless I shorten the flying wires. Pleased though that it seems to be working. just started to peel the covering off the wings to smarten her up abit. alot of hangar rash. The lanc I couldnt check yet as the plug in the wing tip has a broken pin so will need to be replaced. I was told that for a speed controller I could use the control from an electric blanket. Not sure about that but I will have one available soon as the mrs changes her lekky blanket every 2 yrs, and its about due I think. sabotage comes to mind.