Anthony Long 1 Posted May 11, 2023 Share Posted May 11, 2023 Hi Folks. During the shutdown I built several Tony Nijhous 50mm EDF jets and as im sometimes the only one at the Greenacres flying field I have tried to hand launch but being right handed and fly throttle on the right its difficult, I just wondered if any of you guys have plans suitable for these planes, the only ones I can find are in America and megga bucks. Grateful Tony Long. Quote Link to comment Share on other sites More sharing options...
Anthony Long 1 Posted May 11, 2023 Author Share Posted May 11, 2023 Sorry. Plans for a launch dolly. Quote Link to comment Share on other sites More sharing options...
Anthony Long 1 Posted May 11, 2023 Author Share Posted May 11, 2023 1 minute ago, Anthony Long 1 said: Hi Folks. During the shutdown I built several Tony Nijhous 50mm EDF jets and as im sometimes the only one at the Greenacres flying field I have tried to hand launch but being right handed and fly throttle on the right its difficult, I just wondered if any of you guys have plans for a Launch Dolly suitable for these planes, the only ones I can find are in America and megga bucks. Grateful Tony Long. Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted May 11, 2023 Share Posted May 11, 2023 In my experinence of seeing others try to use a take off dolly, they are rarely successful and especially on ground that is not exactly perfectly smooth. One of my very clever flying buddies (both as a flyer and engineer) launches his smaller EDFs from a foot operated catapult - sort of V1 ramp with the model sliding along the top - the mechanism is made from plastic piping so all comes apart for transport and uses a short, soft bungee staked out in front to provide the oomph. The release is rather like that used on a crossbow. I've never seen it fail to work as intended, so might be worth researching something similar. 1 Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted May 11, 2023 Share Posted May 11, 2023 Just Googled 'EDF launching Ramp' and this came up. https://www.rapidrcmodels.com/bungee-launch-systemramp-for-fpvgliderslight-edf-models-self-assembly-4915-p.asp Very similar to my friends setup. Quote Link to comment Share on other sites More sharing options...
Don Fry Posted May 11, 2023 Share Posted May 11, 2023 I’ve tried dollies with very mixed success. The weight of the dolly does not help, the initial run out is without much control, and the hopeful separation always seems a relief rather than an expected reward. Now for these things I used to use a a catapult, with a foot release. Google model aircraft launch catapults. Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted May 11, 2023 Share Posted May 11, 2023 We've tried launching an EDF from a dolly but there simply wasn't enough static thrust to move at a more than a snails pace across mown grass, a bungee assisted launch ramp proved to be the answer. Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted May 11, 2023 Share Posted May 11, 2023 (edited) Planning a maiden of my TN Gnat and Jet Provost in the next couple of days, but I'd be surprised if these wee jets had sufficient excess thrust to take off from a dolly on grass. Dollies can work very well for prop driven aeroplanes, but for small EDFs you are probably better off with a bungee assist and a simple foot pedal release. There are plans available for ramps made from PVC tubing, but back in the early days EDF guru Bob Partington used to have great success around the fly-ins, with a short bungee, a short ply ramp propped up at the front and a simple foot release. Edited May 11, 2023 by leccyflyer Typo Quote Link to comment Share on other sites More sharing options...
Paul De Tourtoulon Posted May 11, 2023 Share Posted May 11, 2023 A Coincidence a local man brought his to launch an electric EPP Spitfire 2 days ago 1 foam wheel on the front and two of the Graupner extra light plastic wheels on the rear all around 100mm diameter, a cross of light samba members and 3 squares of foam to lay the plane on, it weighed nothing,, I have a home built one for my 3.75m 4+ kilo glider, and a third one at the club uses a 3 wheeled one for his 20cc delta with a servo to control the front wheel plugged int the plane, at take off it unplugs it's self, I have seen other ones on 41 mhz, with a separate receiver and servo to control it on the ground with the same radio, And last but not least the Calvissons clubs one, it looks like a mix between a see-saw and a rocket launcher, made of steel and two pvc tubes as rails. Quote Link to comment Share on other sites More sharing options...
PDB Posted May 11, 2023 Share Posted May 11, 2023 Here's a bungee ramp which might provide some ideas https://owlplane.com/product/owlplane-catapult-launcher-10/ Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted May 11, 2023 Share Posted May 11, 2023 Here's Bob's simple ramp mentioned earlier. Works really well and doesn't require an HNC in PVC pipe wrangling. 🙂 1 Quote Link to comment Share on other sites More sharing options...
Glenn Philbrick Posted May 11, 2023 Share Posted May 11, 2023 I use one regularly to launch a fun fighter. As the model does not have rudder the dolly has its own rx and is controlled as you would a normal model with rudder. Quote Link to comment Share on other sites More sharing options...
Caveman Posted May 11, 2023 Share Posted May 11, 2023 A member of our club used a PVC ramp to launch his Cloud Fly glider as, being disabled, he was not able to throw it. This video, in slo-mo because we were interested to see what happened at the moment of launch, shows the rig. Bungee launch.mp4 Again, he couldn't use a foot release, so made a small servo operated release mechanism, operated from his transmitter. GDB 6 Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted May 12, 2023 Share Posted May 12, 2023 This was one I made a few years ago to hold my FMS Fox 3m, it has its own Rx controlled by the same Tx as the model. I had planned to add a motor and a FC board so that it could RTH after launch but never got round to it! Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted May 12, 2023 Share Posted May 12, 2023 Here's my dolly that I use for launching some of my electric funfighters. Manufactured from a scrapped Wendy House. Quote Link to comment Share on other sites More sharing options...
eflightray Posted May 17, 2023 Share Posted May 17, 2023 (edited) Build light, (low wing loading) - https://www.youtube.com/watch?v=NqDJnCiYDV4 Darn video picture not appearing again . Edited May 17, 2023 by eflightray Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted May 17, 2023 Share Posted May 17, 2023 (edited) Didn’t mean to post! Edited May 17, 2023 by Ron Gray Dumb thumbs Quote Link to comment Share on other sites More sharing options...
Colin Low 2 Posted May 18, 2023 Share Posted May 18, 2023 (edited) Tony Nihjuis 70mm EDF Jet Provost 'T5'. It's now had many successful flights from this dolly, along with a few propellor jobs! Edited May 18, 2023 by Colin Low 2 3 Quote Link to comment Share on other sites More sharing options...
Colin Low 2 Posted May 18, 2023 Share Posted May 18, 2023 Tony Nijhuis not Nihjuis ! Quote Link to comment Share on other sites More sharing options...
Paul De Tourtoulon Posted May 18, 2023 Share Posted May 18, 2023 I can't see the point of your RC 'trigger' Ron, my Asw 19 floats off of my dolly. Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted May 18, 2023 Share Posted May 18, 2023 (edited) 3 hours ago, Colin Low 2 said: Tony Nihjuis 70mm EDF Jet Provost 'T5'. It's now had many successful flights from this dolly, along with a few propellor jobs! Note the lovely smooth patch which is clearly very well maintained and ideal for a launching dolly- as I've seen so many times before, anything less than what's in the vid i.e your average club's bit of mown pasture, will throw the model around and out of the dolly. Best to go the catapult route in that case. Nice site and well flown model. Edited May 18, 2023 by Cuban8 2 Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted May 18, 2023 Share Posted May 18, 2023 Saw a most impressive operation of one of those taller glider dollies at the weekend when a clubmate flew a gorgeous large scale Golden Age glider which must have been >3m span off the freshly cut grass, powered by what looked like an implausibly small folding prop in the nose, she was up and climbing out in less than 30 feet. Superb job. 😎 Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted May 18, 2023 Share Posted May 18, 2023 2 hours ago, Paul De Tourtoulon said: can't see the point of your RC 'trigger' Ron, Like you Paul, not everyone can, neither can they see the point of steering and RTH capability! 1 Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted May 20, 2023 Share Posted May 20, 2023 Yesterday's attempted 50mm MiniJet maidens didn't end well, confirmed the perils of hand launching and I might be forced to revisit the launch ramp option. I had a 100% EDF failure rate - the EFlite BAe Hawk wouldn't even taxi, let alone work up enough speed for a take off - tiny wheels on the fixed undercarriage and spongy moss do not make for a high speed experience. The Gnat nosed in and hit the deck on hand launching and the Jet Provost reared up near vertical before falling to earth ten feet in front of us, breaking off the wing and splitting the fuselage. They were both easily repaired on return to the workshop and are ready for another go soon. Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted May 21, 2023 Share Posted May 21, 2023 The repaired Gnat and Jet Provost had another try yesterday, with exactly the same results -all from good strong hand launches. The Gnat just goes down 10 feet in front of the launch, it simply doesn't have enough power. Will have to make some measurements and a rethink. It has flown previously, but IIRC did fall out of the sky during that flight. The Provost performs exactly the same scary manouver, the tail drops, the nose goes high, she half rolls over and comes down vertical on her nose,. with the topside facing the pilot. She has done that on four good string hand launches. On close examination one elevator half is coming up a little bit more than the other, imparting the roll. The throws and CG are as per plan. No damage resulted from the six attempted hand launches yesterday, but a rethink is necessary. Quote Link to comment Share on other sites More sharing options...
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