Just came across a hi-start at Horizon hobby. FYI
http://www.horizonhobby.com/parkzone...0-2-3m-efla650

Includes a good video on how to use a hi-start
https://www.youtube.com/watch?v=ru0tyLi6L74#t=43

Thanks
as much as I hate to admit it have the video instead on the narrative helped. Trying to remember what we did back in the 70s that turned my windward wing into toothpicks.

>>High Reliability / Short Up-Start Launch Considerations?

So my at hand venue is a smooth, sandy seacoast beach which is often deserted in the Spring and Fall -- BUT, I also only have about 200' at low tide and sea breeze is obviously onshore.

The good news is that there may be some thermal possibilities due to differential land/sea heating which induces the seabreeze... plus there's likely a mini-slope effect near the dune line which seems worth exploring

The hope is that I only need to get 100-150' or so of altitude on launch to explore the thermal and slope possibilities. Am wondering if a shortened (100-150') Up-Start rig might do the trick for a 2.2m Parkzone Ka-8 that I just picked up... specifically considering the heavier duty version of the Up-Start from GP with the thicker tubing which is advertised for up to 100" wingspan (vs. the lighter "2m" version).

Are there any special launch considerations when using a short rig?... I don't think I need to go to high tension and, given that I'll be 'feet wet' at the release point would prefer to minimize risks associated with launching towards and over water... much appreciate any tips for achieving highly reliable launches by getting incrementally more comfortable. I don't think I can launch at too low a planned release altitude, if I'm going to have some room to abort a bad launch and get back over the beach.

>> PLAN B: Quadcopter Tow, or Lift & Release?

Another thought I've had for this venue, is to use a stabilized quadcopter to aerotow or lift the Ka-8. Most of the Youtube vids that I've seen have been a bit horrifying -- usual approach has been to drag the glider up vertically by the nose with a 'drop' release from pure hover. Best outcomes have been flyable but only after a big loss in altitude due to recovery needed... and then there's the crash risk from entanglement of the towline in the quad's blades.

I expect it might take a fair amount of practice for a team to establish a nice aerotow profile with a quadcopter -- would need to be smooth to avoid gyro induced oscillations... and might be something best done with wind as this could enable a protocol where the quad pilot maintains near zero ground speed and can focus on the ascent dynamics.

The need for two accomplished pilots (something I won't have often), for me, seems to argue for mounting the glider on the quad with CG aligned and flying the quad in a forward climb by making use of the glider aerodynamics principally for lift -- sort of a quad-assisted take off, or perhaps. a winged-quad concept. Release likely makes sense at altitude with the quad in level forward flight at a modest airspeed in the range of that for hand launch of the glider.

Given that we're exploiting lift from the glider's wings, a pretty modest quadcopter might be all that's needed -- indeed keeping the quad's blades near the wing roots so the rest of the wing can fly in relatively undisturbed air would seem to make sense (vs. brute force). I'm also speculating that control over altitude and direction could be substantially controlled by the quad -- so from the perspective of piloting the quad, this really would be the equivalent of putting a pair of wings on the quad -- something I might be able to practice initially with some spare free flight wings.

Welcome any thoughts, experience, comments that folks might have on either the short Up-Start or copter launches (multi-rotor or helicopter?)... or other approaches to getting my Ka-8 up off the beach, while avoiding landing out -- as in -- LOW (on the water without floats ;-) )...

No special considerations for a shorter hi-start. I have two. One is 100 feet of rubber and 400 feet of line. The other is 25 feet of rubber and 100 feet of line.

Another option for hi-start rubber is a pharmacy or medical supply store if you have one in your area. I know that this is about hi-starts but have to throw these few pics in. This is when we don't have much Thermal activity and the wind isn't blowing for the slope.

Over time I see fewer and fewer people using hi-starts. At our club it is either winch or electric. So I pulled out my hi-start just for fun. I was flying my Supra which is a molded wing competition glider made for the winch. But it still launches very nicely off my hi-start.

Anyone have recommended source for hi-starts these days?

I see https://www.aerofoam.com/highstart-bungees.html Still has top quality products for sale.
https://www.aerofoam.com/highstart-bungees.html

I see Tower is still selling one but no specifics.
https://www.towerhobbies.com/cgi-bin...?&I=LXHNZA&P=7

I see Amazon has a silicone rubber hi-start for sale. 10 meter section. The old Latex were usually stretched to 3x their rested size. This claims you can go to 6X but no info on how much pull that produces. The suggest you can launch a glider up to about 6.5 pounds.
https://www.amazon.com/Bungee-Silico.../dp/B01N8XHUWI

Latex rubber up to 58 feet long
https://www.amazon.com/Rubber-Tubing...E4F&th=1&psc=1

Hobbyking has 10 mm Silicone rubber
https://hobbyking.com/en_us/hobbykin...tart-cord.html

Hello,

Just found your detailed hi start thread and would like to contribute in it, presenting my own design micro bungee for small gliders. This project was initially materialized for the needs of my also own design micro sailplane, the Micro Nova, but it can also be used on most micro gliders, suitable wingspans from 80cm to 120cm.

Since i am new at your forum, i cannot yet upload any photos... so will get back with photos as soon as i am able to.

Regards,
Kazaklis Tasos.

The bungee is modular and consists of three separate parts:
- Special cut Latex surgical tubing (1/4 inchx1/16 half disc section with high elasticity 400%). Length is 6.5-8 meters (varies depending on application)… perfectly split/cut tubing from fresh production batch ensuring longevity… ends equipped with a strong ring and heavy duty swivel.

- Two separate line reels made of XPS and very practical to use with removable axles and easy engage/release line fittings. Line spools of 25 and 35 meters utilizing high elasticity/ yellow colored 0.6mm line… end fittings easily engaged in pennant and bungee end.

- Nylon pennant… its line ends equipped with heavy duty swivel and a small diameter tow ring.

In actual practice this micro bungee offers easy 5min deployment and retrieval… depending on conditions the short of long line can be interchanged easily thanks to the end fittings…very practical to use/ store ensuring hassle free launches of your mini sailplane… Instructions on proper use and tips on launching/model trimming included.

Only item additionally required is a ground anchor/stake that I deliberately omit from the package as its heavy weight and length would only increase shipping cost… a stake is really a low cost item and easily obtainable on most hardware stores so it’s best to obtain one from your end.

When I first started flying model airplanes, I started with an RTF electric called the Aerobird. I joined a club and they taught me how to fly my plane. However, most of the pilots in this club were glider pilots. Their gliders didn't have motors. This was 2003, and batteries were big heavy NiCd packs. Motors were brushed motors that were relatively heavy, and not very efficient. Certainly there were electric gliders, but not a lot of them. So, if you wanted to go thermal soaring, you flew a pure glider. But how do you get it up into the sky?

The hi-start was my first way of launching my first glider. I launched gliders with 2 meter to 3.4 meter wing spans using that hi-start. It was a lot of fun.

Today, most of my thermal soaring is done with electric-powered motors in the nose of the glider. Today's batteries are light, and today's brushless motors are powerful. However, I still have that hi-start and still use it to launch my pure gliders. In fact, I was using it a couple of weeks ago to launch a glider with a 10-foot wing span. It was just beautiful going up.

I presume most new glider pilots are using electric-launched gliders. They are easy AND they provide a degree of safety that we don't have with pure gliders. If you are thermal soaring or slope soaring with a pure glider and you lose the lift, you can end up in a tree or a field or even the water. In this respect, pure gliders are more challenging, but I love flying them, and a hi-start is a great way to launch them.

With an electric glider, if you got too far from the field and the lift dies, or the wind comes up against you, you can power up the motor and get back to the field. I spent many an hour trying to get a glider out of a tree because the lift disappeared, and I could not make it back safely to the landing area.

Hello,

Thank you for your response,

You are very correct that a pure glider is and will always be more challenging and somewhat risky compared to an electric assisted one… I started by using a hi-start 40 years ago launching my scratch built Mini Bird and I can still remember the thrill and excitement of my first ascents.

A bungee launch is pure magic and if done correctly may be quite safe but preparation of equipment and correct trimming of the sailplane is a must… also a pure glider will be more efficient in flight because the folding prop-spinner creates additional drag no matter how tight it folds against the fuselage which is also bulkier to house the motor-ESC-Lipo.

Flying a pure glider with no luxury of a motor to help in tight situations will make a pilot better appreciate his and the model abilities… it’s a big conversation issue and after decades of flying both electric and pure glider models I can say it’s a tossup and matter of personal preference and challenge.

My extensively involved F5J competition years (after launch no motor to rely on) definitely improved my piloting skills and strangely after hundreds of competition flights I had only a handful of out landings… I attribute this to carefully judging my sailplane potential and taking only logical risks, this relatively safe tactic paid off with 35 trophies collected over a span of seven competitive years.

In these modern times most people are choosing the electric way but may miss a part of pure glider soaring that cannot be easily described unless you actually experience it.

Currently I am in the process of making the molds of my new micro glider design… it’s the Tiny G! with 620mm span and of all composite construction, will be hand or discus launched, or slope soared in diminutive slopes… but I will also fabricate a special micro hi-start for this size using FAI rubber power materials.

Will make some posts in due time of his exciting new project…

Keep on the lift side!

Tasos.